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  • 1.
    Ahlström, Christer
    et al.
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Hult, Peter
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Rask, Peter
    Örebro university.
    Karlsson, Jan-Erik
    Nylander, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Dahlström, Ulf
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Feature Extraction for Systolic Heart Murmur Classification2006In: Annals of Biomedical Engineering, ISSN 0090-6964, E-ISSN 1573-9686, Vol. 34, no 11, p. 1666-1677Article in journal (Refereed)
    Abstract [en]

    Heart murmurs are often the first signs of pathological changes of the heart valves, and they are usually found during auscultation in the primary health care. Distinguishing a pathological murmur from a physiological murmur is however difficult, why an “intelligent stethoscope” with decision support abilities would be of great value. Phonocardiographic signals were acquired from 36 patients with aortic valve stenosis, mitral insufficiency or physiological murmurs, and the data were analyzed with the aim to find a suitable feature subset for automatic classification of heart murmurs. Techniques such as Shannon energy, wavelets, fractal dimensions and recurrence quantification analysis were used to extract 207 features. 157 of these features have not previously been used in heart murmur classification. A multi-domain subset consisting of 14, both old and new, features was derived using Pudil’s sequential floating forward selection (SFFS) method. This subset was compared with several single domain feature sets. Using neural network classification, the selected multi-domain subset gave the best results; 86% correct classifications compared to 68% for the first runner-up. In conclusion, the derived feature set was superior to the comparative sets, and seems rather robust to noisy data.

  • 2.
    Ahn, Henrik
    et al.
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Baranowski, Jacek
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Dahlin, Lars-Göran
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Nielsen, Niels-Erik
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Cardiology UHL.
    Nylander, Eva
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Wallby, Lars
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    TAVI without concomitant balloon dilatation2012Conference paper (Other academic)
  • 3.
    Ahn, Henrik Casimir
    et al.
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Baranowski, J
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Nielsen, Nils Erik
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Nylander, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Tamas, Eva
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Wallby, Lars
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Transcatheter aortic valve implantation in high-risk surgical candidates with low risk-scores1984Conference paper (Other academic)
  • 4.
    Al-Ahmad, A.
    et al.
    Cardiac Arrhythmia Service, Stanford University Medical School, Stanford, CA, United States.
    Wigström, Lars
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Sandner-Porkristl, D.
    Siemens AG, Medical Solutions, Forchheim, Germany.
    Wang, P.J.
    Cardiac Arrhythmia Service, Stanford University Medical School, Stanford, CA, United States.
    Zei, P.C.
    Cardiac Arrhythmia Service, Stanford University Medical School, Stanford, CA, United States.
    Boese, J.
    Siemens AG, Medical Solutions, Forchheim, Germany.
    Lauritsch, G.
    Siemens AG, Medical Solutions, Forchheim, Germany.
    Moore, T.
    Siemens AG, Medical Solutions, Forchheim, Germany.
    Chan, F.
    Department of Radiology, Stanford University Medical School, Stanford, CA, United States.
    Fahrig, R.
    Department of Radiology, Stanford University Medical School, Stanford, CA, United States.
    Time-resolved three-dimensional imaging of the left atrium and pulmonary veins in the interventional suite-A comparison between multisweep gated rotational three-dimensional reconstructed fluoroscopy and multislice computed tomography2008In: Heart Rhythm, ISSN 1547-5271, Vol. 5, no 4, p. 513-519Article in journal (Refereed)
    Abstract [en]

    Background: Cardiac computed tomography (CT) is commonly used to visualize left atrial (LA) anatomy for ablation of atrial fibrillation. We have developed a new imaging technique that allows acquisition and visualization of three-dimensional (3D) cardiac images in the catheter lab. Objective: We sought to compare LA and pulmonary vein (PV) dimensions acquired using gated multisweep rotational fluoroscopy (C-arm CT) system and multislice computed tomography (MSCT) in an in vivo porcine model. Methods: A Siemens AXIOM Artis dTA C-arm system (Siemens AG, Medical Solutions) was modified to allow acquisition of four bidirectional sweeps during synchronized acquisition of the electrocardiogram signal to allow retrospective gating. C-arm CT image volumes were then reconstructed. Gated MSCT (SOMATOM Sensation 16 and 64, Siemens AG, Medical Solutions) and C-arm CT images were acquired in six animals. The two main PV diameters were measured in orthogonal axes. LA volumes were calculated. C-arm CT measurements were compared with the MSCT measurements. Results: The average PV diameters using the C-arm CT were 2.24 × 1.35 cm, versus 2.27 × 1.38 cm for CT. The average difference was 0.034 cm (1.9%) between the C-arm CT and standard CT. The average LA volume using MSCT was 49.1 ± 12.7 cm3, as compared with 51.0 ± 8.7 cm3 obtained by the C-arm CT. The average difference between the C-arm CT and the MSCT was 1.9 cm3 (3.7%). There were no significant differences in either the PV or LA measurements. Conclusions: Visualization of 3D cardiac anatomy during ablation procedures is possible and highly accurate. The 3D cardiac reconstructions acquired during ablation procedures will be valuable for procedural planning and guidance. © 2008 Heart Rhythm Society.

  • 5.
    Alehagen, Urban
    et al.
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences.
    Eriksson, H.
    Department of Medicine, Sahlgrenska Univ. Hosp.-Östra, Gothenburg, Sweden.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Dahlström, Ulf
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences.
    Heart failure in the elderly: characteristics of a Swedish primary health care population2002In: Heart Drug, ISSN 1422-9528, E-ISSN 1424-0556, Vol. 2, no 5, p. 211-220Article in journal (Refereed)
    Abstract [en]

    Background: Heart failure (HF) is a challenge to diagnose and treat according to guidelines. Few studies have been performed in elderly subjects with symptoms that might be associated with HF in primary health care.

    Objective: To study elderly patients presenting with symptoms possibly associated with HF, with respect to systolic and diastolic function, B-type natriuretic peptide (BNP) levels and treatment.

    Methods: A cardiologist examined 415 elderly (65–82 years) patients with symptoms of dyspnoea, fatigue and/or peripheral oedema. All patients underwent echocardiography and plasma BNP determination. Systolic function was determined semiquantitatively, and ejection fraction (EF) <40% was considered to be reduced. Abnormal diastolic function was defined as a reduced ratio of peak early diastolic filling velocity to peak filling velocity at atrial contraction (E/A ratio; age adjusted) or an abnormal pattern of pulmonary venous flow.

    Results: Forty-eight percent of the patients showed abnormal systolic (26%) or diastolic function (22%). A majority of the patients with diastolic HF had relaxation abnormalities and neither pseudonormal nor restrictive filling patterns. Increased levels of BNP were found in the group with impaired systolic function. More than half of those with EF <40% were not receiving angiotensin-converting enzyme inhibitions at all, or were on a suboptimal dose, whereas others were on treatment for an HF diagnosis despite normal cardiac function.

    Conclusion: Diagnostic tools that are more objective than clinical examination are needed for the diagnosis of HF.

  • 6.
    Ambarki, K.
    et al.
    Umeå University, Sweden .
    Lindqvist, T.
    Umeå University, Sweden .
    Wahlin, A.
    Umeå University, Sweden .
    Petterson, E.
    SyntheticMR ABE, Linköping, Sweden .
    Warntjes, Marcel Jan Bertus
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Birgander, R.
    Umeå University, Sweden .
    Malm, J.
    Umeå University, Sweden .
    Eklund, A.
    Umeå University, Sweden Umeå University, Sweden .
    Evaluation of Automatic Measurement of the Intracranial Volume Based on Quantitative MR Imaging2012In: American Journal of Neuroradiology, ISSN 0195-6108, E-ISSN 1936-959X, Vol. 33, no 10, p. 1951-1956Article in journal (Refereed)
    Abstract [en]

    BACKGROUND AND PURPOSE: Brain size is commonly described in relation to ICV, whereby accurate assessment of this quantity is fundamental. Recently, an optimized MR sequence (QRAPMASTER) was developed for simultaneous quantification of T1, T2, and proton density. ICV can be measured automatically within minutes from QRAPMASTER outputs and a dedicated software, SyMRI. Automatic estimations of ICV were evaluated against the manual segmentation. MATERIALS AND METHODS: In 19 healthy subjects, manual segmentation of ICV was performed by 2 neuroradiologists (Obs1, Obs2) by using QBrain software and conventional T2-weighted images. The automatic segmentation from the QRAPMASTER output was performed by using SyMRI. Manual corrections of the automatic segmentation were performed (corrected-automatic) by Obs1 and Obs2, who were blinded from each other. Finally, the repeatability of the automatic method was evaluated in 6 additional healthy subjects, each having 6 repeated QRAPMASTER scans. The time required to measure ICV was recorded. RESULTS: No significant difference was found between reference and automatic (and corrected-automatic) ICV (P greater than .25). The mean difference between the reference and automatic measurement was -4.84 +/- 19.57 mL (or 0.31 +/- 1.35%). Mean differences between the reference and the corrected-automatic measurements were -0.47 +/- 17.95 mL (-0.01 +/- 1.24%) and -1.26 +/- 17.68 mL (-0.06 +/- 1.22%) for Obs1 and Obs2, respectively. The repeatability errors of the automatic and the corrected-automatic method were less than1%. The automatic method required 1 minute 11 seconds (SD = 12 seconds) of processing. Adding manual corrections required another 1 minute 32 seconds (SD = 38 seconds). CONCLUSIONS: Automatic and corrected-automatic quantification of ICV showed good agreement with the reference method. SyMRI software provided a fast and reproducible measure of ICV.

  • 7.
    Aneq Åström, Meriam
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Brudin, Lars
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Evaluation of Right and Left Ventricular Function Using Speckle Tracking Echocardiography in Patients with Arrhythmogenic Right Ventricular Cardiomyopathy and Their First Degree RelativesManuscript (preprint) (Other academic)
    Abstract [en]

    Introduction and aim: The identification of right ventricular abnormalities in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) in early stages is still difficult. The aim of this study was to investigate if longitudinal strain based on speckle tracking can detect subtle right (RV) or left ventricular (LV) dysfunction as an early sign of ARVC.

    Methods and results: Seventeen male patients, fulfilling Task force criteria for ARVC, 49 (32-70) years old, nineteen male first degree relatives 29 (19-73) y.o. and twenty-two healthy male volunteers 36 (24-66) y.o participated in the study. Twelve-lead and signal-averaged electrocardiograms were recorded. All subjects underwent echocardiography. LV and RV diameters, peak systolic velocity from tissue Doppler and longitudinal strain based on speckle tracking were measured from the basal and mid segments in both ventricles. RV longitudinal strain measurement was successful in first degree relatives and controls (95 resp. 86%) but less feasible in patients (59%). Results were not systematically different between first degree relatives and controls. Using discriminant analysis, we then developed an index based on echocardiographic parameters. All normal controls had an index <l while patients with abnormal ventricles had an index between 1-4. Some of the first degree relatives deviated from the normal pattern.

    Conclusion: Longitudinal strain of LV and RV segments was significantly lower in patients than in relatives and controls. An index was developed incorporating dimensional and functional echocardiographic parameters. In combination with genetic testing this index might help to detect early phenotype expression in mutation carriers.

  • 8.
    Aneq Åström, Meriam
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Fluur, Christina
    Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Cardiology UHL.
    Rehnberg, Malin
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Söderkvist, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Gunnarsson, Cecilia
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Novel plakophilin2 mutation. Three generation family with arrhythmogenic right ventricular cardiomyopathy2012In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 46, no 2, p. 72-75Article in journal (Refereed)
    Abstract [en]

    Objectives: The autosomal dominant form of arrhythmogenic right ventricular cardiomyopathy (ARVC)has been linked to mutations in desmosomal proteins. Different studies have shown that amutation in plakophilin-2 (PKP 2) is a frequent genetic cause for ARVC. We describe a newmutation in the PKP2 gene, the genotype-phenotype variation in this mutation and its clinicalconsequences.

    Design: Individuals in a three generation family were investigated after the sudden cardiac death of a young male. Clinical evaluation, electrocardiography, echocardiography, magnetic resonance imaging, endomyocardial biopsy and genetic testing were performed.

    Results: A novel heterozygote mutation, a c.368G>A transition, located in exon 3 of the PKP2 gene was found (p.Trp123X). The phenotype was characterized by arrhythmia at an early age in some individuals, with mild abnormalities on imaging. However a relative carrying this mutation, with positive findings on endomyocardial biopsy had an otherwise normal phenotype, for 16 years, whereas a relative fulfilling the modified Task Force Criteria for ARVC turned out to be a non-carrier.

    Conclusions: This shows the variable penetrance and phenotypic expression in ARVC and highlights the need of genetic testing as well as a thorough phenotype examination as a part of the investigations in ARVC pedigrees.

  • 9.
    Aneq Åström, Meriam
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Ebbers, Tino
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Determination of right ventricular volume and function using multiple axially rotated MRI slices2011In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 31, no 3, p. 233-239Article in journal (Refereed)
    Abstract [en]

    Pandgt;Background: The conventional magnetic resonance imaging (MRI) method for right ventricular (RV) volume and motion, using short-axis (SA) orientation, is limited by RV anatomy and shape. We suggest an orientation based on six slices rotated around the long axis of the RV, rotated long axis (RLA). Materials and methods: Three phantoms were investigated in SA and RLA using cine balanced steady-state free precession MRI. Volumes were calculated based on segmentation and checked against true volumes. In 23 healthy male volunteers, we used six long-axis planes from the middle of the tricuspid valve to the RV apex, rotated in 30 degrees increments. For comparison, short-axis slices were acquired. Imaging parameters were identical in both acquisitions. Results: Right ventricular end-diastolic (EDV), end-systolic (ESV) and stroke volumes (SV) determined in the RLA 179 center dot 1 +/- 29 center dot 3; 80 center dot 1 +/- 17 center dot 1; 99 center dot 3 +/- 16 center dot 9 ml and in the SA were 174 center dot 0 +/- 21 center dot 1; 78 center dot 8 +/- 13 center dot 6; 95 center dot 3 +/- 14 center dot 5 ml with P-values for the difference from 0 center dot 17 to 0 center dot 64 (ns). Interobserver variability ranged between 3 center dot 2% and 6 center dot 6% and intraobserver variability between 2 center dot 8% and 6 center dot 8%. In SA views, consensus for the definition of the basal slice was necessary in 39% of the volunteers for whom the average volume change was 20% in ESV and 10% in EDV. Conclusions: The RLA method results in better visualization and definition of the RV inflow, outflow and apex. Accurate measurement of RV volumes for diagnosis and follow-up of cardiac diseases are enhanced by the RLA orientation, even though additional acquisition time is required.

  • 10.
    Appel, Carl-Fredrik
    et al.
    Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland. Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences.
    Hultkvist, Henrik
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Ahn, Henrik Casimir
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Nielsen, Niels Erik
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Cardiology UHL.
    Freter, Wolfgang
    Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland. Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences.
    Vánky, Farkas
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Transcatheter versus surgical treatment for aortic stenosis: Patient selection and early outcome2012In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 46, no 5, p. 301-307Article in journal (Refereed)
    Abstract [en]

    Objectives. To describe short-term clinical and echocardiography outcomes in patients undergoing transcatheter aortic valve implantation (TAVI) and surgical aortic valve replacement (SAVR). To explore patient selection criteria for treatment with TAVI. Design. TAVI patients (n = 45) were matched to SAVR patients (n = 45) with respect to age within +/- 10 years, sex and systolic left ventricular function. Results. TAVI patients were older, 82 +/- 8 versus 78 +/- 5 years (p = 0.005) and they had higher logEuroSCORE, 16 +/- 11% versus 8 +/- 4% (p andlt; 0.001). There were no significant differences in 30 days mortality, stroke and myocardial infarction. TAVI patients received less erythrocyte (53% vs. 78%, p = 0.03) and thrombocyte (7% vs. 27%, p = 0.02) transfusions. Postoperative atrial fibrillation was less common (18% vs. 60%, p andlt; 0.001) in the TAVI group. Paravalvular regurgitation was more common in TAVI patients (87% vs. 0%, p andlt; 0.001) and 27% had access site complications. Aortic transvalvular velocity was 2.3 +/- 0.4 m/s versus 2.6 +/- 0.5 m/s (p = 0.002) and mean valve pressure gradient was 12 +/- 4 mmHg versus 15 +/- 5 mmHg (p = 0.01) in the TAVI and SAVR groups, respectively. Twenty-nine (64%) of the TAVI patients had logEuroSCORE andlt; 15%. Conclusions. Both TAVI and SAVR have good short term clinical outcome with excellent hemodynamic result. In clinical practice, factors other than high logEuroSCORE play an important role in patient selection for TAVI.

  • 11.
    Areskog, Nils-Holger
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Undergraduate interprofessional education at the Linkoping Faculty of Health Sciences - How it all started2009In: JOURNAL OF INTERPROFESSIONAL CARE, ISSN 1356-1820, Vol. 23, no 5, p. 442-447Article in journal (Refereed)
    Abstract [en]

    The Linkoping Faculty of Health Sciences is a pioneer of interprofessional education (IPE) at the undergraduate level. It was started in 1986 in full scale with six health educations involved. The vision and how it became a reality is described as well as possible advantages and constraints. It is important to have one common pedagogic principle for all educations involved. Problem based learning was chosen and introduced during the initial study module (10 wks). Thereafter IPE comes back during the curricula with common seminars, study days and ward training. Since the start there have been several revisions of the IPE but the nucleus is still there after more than twenty years.

  • 12.
    Arzani, Amirhossein
    et al.
    IIT.
    Dyverfeldt, Petter
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Ebbers, Tino
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Department of Science and Technology, Media and Information Technology. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Shadden, Shawn C
    IIT.
    In Vivo Validation of Numerical Prediction for Turbulence Intensity in an Aortic Coarctation2012In: Annals of Biomedical Engineering, ISSN 0090-6964, E-ISSN 1573-9686, Vol. 40, no 4, p. 860-870Article in journal (Refereed)
    Abstract [en]

    This paper compares numerical predictions of turbulence intensity with in vivo measurement. Magnetic resonance imaging (MRI) was carried out on a 60-year-old female with a restenosed aortic coarctation. Time-resolved three-directional phase-contrast (PC) MRI data was acquired to enable turbulence intensity estimation. A contrast-enhanced MR angiography (MRA) and a time-resolved 2D PCMRI measurement were also performed to acquire data needed to perform subsequent image-based computational fluid dynamics (CFD) modeling. A 3D model of the aortic coarctation and surrounding vasculature was constructed from the MRA data, and physiologic boundary conditions were modeled to match 2D PCMRI and pressure pulse measurements. Blood flow velocity data was subsequently obtained by numerical simulation. Turbulent kinetic energy (TKE) was computed from the resulting CFD data. Results indicate relative agreement (error a parts per thousand 10%) between the in vivo measurements and the CFD predictions of TKE. The discrepancies in modeled vs. measured TKE values were within expectations due to modeling and measurement errors.

  • 13.
    Bak, Zoltan
    et al.
    Linköping University, Department of Medical and Health Sciences, Anesthesiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Surgery UHL.
    Abildgård, Lars
    Lisander, Björn
    Linköping University, Department of Medical and Health Sciences, Anesthesiology. Linköping University, Faculty of Health Sciences.
    Janerot Sjöberg, Birgitta
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Transesophageal echocardiographic hemodynamic monitoring during preoperative acute normovolemic hemodilution2000In: Anesthesiology, ISSN 0003-3022, Vol. 92, no 5, p. 1250-1256Article in journal (Refereed)
    Abstract [en]

    Background: Preoperative acute normovolemic hemodilution may compromise oxygen transport. The aims of our study were to describe the hemodynamic effects of normovolemic hemodilution and to determine its effect on systolic and diastolic cardiac function by multiplane transesophageal echocardiography.

    Methods: In eight anesthetized patients (aged 13-51 yr) without heart disease, hemoglobin was reduced in steps from 123 ± 8 (mean ± SD) to 98 ± 3 and to 79 ± 5 g/l. Hemodynamic measurements (intravascular pressures, thermodilution cardiac output, and echocardiographic recordings) were obtained during a stabilization period and at each level of hemodilution. Left ventricular wall motion was monitored continuously, and Doppler variables, annular motion, and changes in ejection fractional area were analyzed off-line.

    Results: During hemodilution, cardiac output by thermodilution increased by 16 ± 7% and 26 ± 10%, corresponding well to the increase in cardiac output as measured by Doppler (difference, 0.32 ± 1.2 l/min). Systemic vascular resistance fell 16 ± 14% and 23 ± 9% and pulmonary capillary wedge pressure increased slightly (2 ± 2 mmHg), whereas other pressures, heart rate, wall motion, and diastolic Doppler variables remained unchanged. Ejection fractional area change increased from 44 ± 7% to 54 ± 10% and 60 ± 9% as a result of reduced end-systolic and increased end-diastolic left ventricular areas.

    Conclusions: A reduction in hemoglobin to 80 g/l during acute normovolemic hemodilution does not normally compromise systolic or diastolic myocardial function as determined by transesophageal echocardiography. Preload, left ventricular ejection fraction, and cardiac output increase with a concomitant fall in systemic vascular resistance.

  • 14.
    Bak, Zoltan
    et al.
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    Sjöberg, Folke
    Linköping University, Department of Clinical and Experimental Medicine, Burn Unit . Linköping University, Faculty of Health Sciences.
    Eriksson, Olle
    Linköping University, Department of Computer and Information Science, Statistics. Linköping University, Faculty of Arts and Sciences.
    Steinvall, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Janerot Sjöberg, Birgitta
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Cardiac dysfunction after burns2008In: Burns, ISSN 0305-4179, E-ISSN 1879-1409, Vol. 34, no 5, p. 603-609Article in journal (Refereed)
    Abstract [en]

    Objectives

    Using transoesophageal echocardiography (TEE) we investigated the occurrence, and the association of possible abnormalities of motion of the regional wall of the heart (WMA) or diastolic dysfunction with raised troponin concentrations, or both during fluid resuscitation in patients with severe burns.

    Patients and methods

    Ten consecutive adults (aged 36–89 years, two women) with burns exceeding 20% total burned body surface area who needed mechanical ventilation were studied. Their mean Baux index was 92.7, and they were resuscitated according to the Parkland formula. Thirty series of TEE examinations and simultaneous laboratory tests for myocyte damage were done 12, 24, and 36 h after the burn.

    Results

    Half (n = 5) the patients had varying grades of leakage of the marker that correlated with changeable WMA at 12, 24 and 36 h after the burn (p ≤ 0.001, 0.044 and 0.02, respectively). No patient had WMA and normal concentrations of biomarkers or vice versa. The mitral deceleration time was short, but left ventricular filling velocity increased together with stroke volume.

    Conclusion

    Acute myocardial damage recorded by both echocardiography and leakage of troponin was common, and there was a close correlation between them. This is true also when global systolic function is not deteriorated. The mitral flow Doppler pattern suggested restrictive left ventricular diastolic function.

  • 15.
    Bak, Zoltan
    et al.
    Linköping University, Department of Medical and Health Sciences, Anesthesiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Surgery UHL.
    Sjöberg, Folke
    Linköping University, Department of Clinical and Experimental Medicine, Burn Center. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Reconstruction Centre, Department of Plastic Surgery, Hand surgery UHL.
    Eriksson, Olle
    Linköping University, Department of Computer and Information Science, Statistics. Linköping University, Faculty of Arts and Sciences.
    Steinvall, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Reconstruction Centre, Department of Plastic Surgery, Hand surgery UHL.
    Janerot Sjöberg, Birgitta
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Hemodynamic Changes During Resuscitation After Burns Using the Parkland Formula2009In: Journal of Trauma, ISSN 0022-5282, E-ISSN 1529-8809, Vol. 66, no 2, p. 329-336Article in journal (Refereed)
    Abstract [en]

    Background: The Parkland formula (2-4 mL/kg/burned area of total body surface area %) with urine output and mean arterial pressure (MAP) as endpoints; for the fluid resuscitation in burns is recommended all over the world. There has recently been a discussion on whether central circulatory endpoints should be used instead, and also whether volumes of fluid should be larger. Despite this, there are few central hemodynamic data available in the literature about the results when the formula is used correctly.

    Methods: Ten burned patients, admitted to our unit early, and with a burned area of >20% of total body sur-face area were investigated at 12, 24, and 36 hours after injury. Using transesophageal echocardiography, pulmonary artery catheterization, and transpulmonary thermodilution to monitor them, we evaluated the cardiovascular coupling when urinary output and MAP were used as endpoints.

    Results: Oxygen transport variables, heart rate, MAP, and left ventricular fractional area, did not change significantly during fluid resuscitation. Left ventricular end-systolic and end-diastolic area and global end-diastolic volume index increased from subnormal values at 12 hours to normal ranges at 24 hours after the burn. Extravascular lung intrathoracal blood volume ratio was increased 12 hours after the burn.

    Conclusions: Preload variables, global systolic function, and oxygen transport recorded simultaneously by three separate methods showed no need to increase the total fluid volume within 36 hours of a major burn. Early (12 hours) signs of central circulatory hypovolemia, however, support more rapid infusion of fluid at the beginning of treatment.

  • 16.
    Bak, Zoltan
    et al.
    Linköping University, Department of Medicine and Health Sciences, Anesthesiology . Linköping University, Faculty of Health Sciences.
    Sjöberg, Folke
    Linköping University, Department of Clinical and Experimental Medicine, Burn Unit . Linköping University, Faculty of Health Sciences.
    Rousseau, Andreas
    Linköping University, Department of Medicine and Health Sciences, Anesthesiology . Linköping University, Faculty of Health Sciences.
    Janerot Sjöberg, Birgitta
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Steinvall, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Human cardiovascular dose-response to supplemental oxygen2007In: Acta Physiologica, ISSN 1748-1708, E-ISSN 1748-1716, Vol. 191, no 1, p. 15-24Article in journal (Refereed)
    Abstract [en]

    Aim: The aim of the study was to examine the central and peripheral cardiovascular adaptation and its coupling during increasing levels of hyperoxaemia. We hypothesized a dose-related effect of hyperoxaemia on left ventricular performance and the vascular properties of the arterial tree.

    Methods: Oscillometrically calibrated arterial subclavian pulse trace data were combined with echocardiographic recordings to obtain non-invasive estimates of left ventricular volumes, aortic root pressure and flow data. For complementary vascular parameters and control purposes whole-body impedance cardiography was applied. In nine (seven males) supine, resting healthy volunteers, aged 23–48 years, data was collected after 15 min of air breathing and at increasing transcutaneous oxygen tensions (20, 40 and 60 kPa), accomplished by a two group, random order and blinded hyperoxemic protocol.

    Results: Left ventricular stroke volume [86 ± 13 to 75 ± 9 mL (mean ± SD)] and end-diastolic area (19.3 ± 4.4 to 16.8 ± 4.3 cm2) declined (P < 0.05), and showed a linear, negative dose–response relationship to increasing arterial oxygen levels in a regression model. Peripheral resistance and characteristic impedance increased in a similar manner. Heart rate, left ventricular fractional area change, end-systolic area, mean arterial pressure, arterial compliance or carbon dioxide levels did not change.

    Conclusion: There is a linear dose–response relationship between arterial oxygen and cardiovascular parameters when the systemic oxygen tension increases above normal. A direct effect of supplemental oxygen on the vessels may therefore not be excluded. Proximal aortic and peripheral resistance increases from hyperoxaemia, but a decrease of venous return implies extra cardiac blood-pooling and compensatory relaxation of the capacitance vessels.

  • 17.
    Baranowska, Irena
    et al.
    Silesian Technical University, Poland .
    Magiera, Sylwia
    Silesian Technical University, Poland .
    Baranowski, Jacek
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Clinical applications of fast liquid chromatography: A review on the analysis of cardiovascular drugs and their metabolites2013In: Journal of chromatography. B, ISSN 1570-0232, E-ISSN 1873-376X, Vol. 927, no SI, p. 54-79Article, review/survey (Refereed)
    Abstract [en]

    One of the major challenges facing the medicine today is developing new therapies that enhance human health. To help address these challenges the utilization of analytical technologies and high-throughput automated platforms has been employed; in order to perform more experiments in a shorter time frame with increased data quality. In the last decade various analytical strategies have been established to enhance separation speed and efficiency in liquid chromatography applications. Liquid chromatography is an increasingly important tool for monitoring drugs and their metabolites. Furthermore, liquid chromatography has played an important role in pharmacokinetics and metabolism studies at these drug development stages since its introduction. This paper provides an overview of current trends in fast chromatography for the analysis of cardiovascular drugs and their metabolites in clinical applications. Current trends in fast liquid chromatographic separations involve monolith technologies, fused-core columns, high-temperature liquid chromatography (HTLC) and ultra-high performance liquid chromatography (UHPLC). The high specificity in combination with high sensitivity makes it an attractive complementary method to traditional methodology used for routine applications. The practical aspects of, recent developments in and the present status of fast chromatography for the analysis of biological fluids for therapeutic drug and metabolite monitoring, pharmacokinetic studies and bioequivalence studies are presented.

  • 18.
    Baranowska, Irena
    et al.
    Silesian Technical University.
    Markowski, Piotr
    Silesian Technical University.
    Baranowski, Jacek
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Development and Validation of an HPLC Method for the Simultaneous Analysis of 23 Selected Drugs Belonging to Different Therapeutic Groups in Human Urine Samples2009In: ANALYTICAL SCIENCES, ISSN 0910-6340, Vol. 25, no 11, p. 1307-1313Article in journal (Refereed)
    Abstract [en]

    We have developed and validated a new and reliable gradient reversed-phase high-performance liquid chromatography (RP-HPLC) method with a diode array detector (DAD) for the simultaneous separation and determination of 23 frequently prescribed selected drugs belonging to different therapeutic groups in human urine samples. For the drugs listed below, this method of analysis for human urine was also successfully applied to determine urine concentrations of these drugs in samples from treated patients: enalapril (ENA), paracetamol (PAR), sotatol (SOT), dipyrone (DIP), vancomycin (VAN), captopril (CAP), fluconazole (FLU), cefazolin (CEF), metoprolol (MET), aspirin (ASP), ticlopidine (TIC), prednisolone (PRE), propranolol (PRO), digoxin (DIG), sildenafil (SIL), furosemide (FUR), dexamethasone (DEX), carvedilol (CAR), ketoprofen (KET), nifedipine (NIF), terbinafine (TER), acenocoumarol (ACE) and spironolactone (SPI). Separation of the analytes was achieved by RP-HPLC-DAD with a mobile phase composed of acetonitrile, methanol and 0.05% trifluoroacetic acid in water using a gradient elution program. Good linear relationships over the investigated concentration ranges were observed with values of r(2) higher than 0.998 for all of the drugs. The intra-day and inter-day precisions of this method were evaluated with RSD values less than 4.26 and 5.42%, respectively. The relative recoveries of the 23 investigated compounds ranged from 93.60 to 106.00% with RSD values less than 4.46%. An expanded uncertainty budget was constructed for all investigated drugs in human urine samples.

  • 19.
    Baranowski, Jacek
    et al.
    Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Ahn, Henrik
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Freter, Wolfgang
    Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Nielsen, Niels-Erik
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Cardiology UHL.
    Nylander, Eva
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Janerot-Sjöberg, Birgitta
    Linköping University, Department of Biomedical Engineering, Biomedical Instrumentation. Linköping University, The Institute of Technology. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Sandborg, Michael
    Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL.
    Wallby, Lars
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Echo-guided presentation of the aortic valve minimises contrast exposure in transcatheter valve recipients2011In: Catheterization and cardiovascular interventions, ISSN 1522-1946, E-ISSN 1522-726X, Vol. 77, no 2, p. 272-275Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES:

    We have developed a method using transthoracic echocardiography in establishing optimal visualization of the aortic root, to reduce the amount of contrast medium used in each patient.

    BACKGROUND:

    During transcatheter aortic valve implantation, it is necessary to obtain an optimal fluoroscopic projection for deployment of the valve showing the aortic ostium with the three cusps aligned in the beam direction. This may require repeat aortic root angiograms at this stage of the procedure with a high amount of contrast medium with a risk of detrimental influence on renal function.

    METHODS:

    We studied the conventional way and an echo guided way to optimize visualisation of the aortic root. Echocardiography was used initially allowing easier alignment of the image intensifier with the transducer's direction.

    RESULTS:

    Contrast volumes, radiation/fluoroscopy exposure times, and postoperative creatinine levels were significantly less in patients having the echo-guided orientation of the optimal fluoroscopic angles compared with patients treated with the conventional approach.

    CONCLUSION:

    We present a user-friendly echo-guided method to facilitate fluoroscopy adjustment during transcatheter aortic valve implantation. In our series, the amounts of contrast medium and radiation have been significantly reduced, with a concomitant reduction in detrimental effects on renal function in the early postoperative phase.

  • 20. Bech-Hanssen, O
    et al.
    Caidahl, K
    Wallentin, I
    Brandberg, J
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Aortic prosthetic valve design and size: Relation to Doppler echocardiographic findings and pressure recovery - An in vitro study2000In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 13, no 1, p. 39-50Article in journal (Refereed)
    Abstract [en]

    The extent to which Doppler echocardiography information can be used in the assessment of prosthesis hemodynamic performance is still controversial. The goals of our study were to assess the importance of valve design and size both on Doppler echocardiography findings and on pressure recovery in a fluid mechanics model. We performed Doppler and catheter measurements in the different orifices of the bileaflet St Jude (central and side orifices), the monoleaflet Omnicarbon (major and minor orifices), and the stented Biocor porcine prosthesis. Net pressure gradients were predicted from Doppler flow velocities, assuming either independence or dependence of valve size. The peak Doppler estimated gradients (mean +/- SD for sizes 21 to 27) were 21 +/- 10.3 rum Hg for St Jude, 18 +/- 9.3 mm Hg for Omnicarbon, and 37 +/- 14.5 mm Hg for Biocor (P <.05 for St Jude and Omnicarbon vs Biocor). The pressure recovery (proportion of peak catheter pressure) was 53% +/- 8.6% for central-St Jude, 29% +/- 8.9% for side-St Jude, 20% +/- 5.6% for major-Omnicarbon, 23% +/- 7.4% for minor-Omnicarbon, and 18% +/- 3.6% for Biocor (P <.05 for central-St Jude and side-St Jude vs Omnicarbon and Biocor). Valve sizes (2) significantly influenced pressure recovery (y in percentage) (central-St Jude: y = 3.7x - 35.9, r = 0.88, P =.0001, major-Omnicarbon: y = 2.1x - 30.3, r = 0.85, P =.0001). By assuming dependence of valve size, Doppler was able to predict net pressure gradients in St Jude with a mean difference between net catheter and Doppler-predicted gradient of - 3.8 +/- 2.5 mm Hg. In conclusion, prosthetic value design and size influence the degree of pressure recovery, making Doppler gradients potentially misleading in both the assessment of hemodynamic performance and the comparison of one design with another. The preliminary results indicate that net gradient can be predicted from Doppler gradients,

  • 21.
    Bech-Hanssen, O.
    et al.
    Department of Clinical Physiology, Sahlgrenska University Hospital, SE-413 45 Göteborg, Sweden.
    Gjertsson, P.
    Gjertsson, P..
    Houltz, E.
    Department of Clinical Physiology, Sahlgrenska University Hospital, SE-413 45 Göteborg, Sweden.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Loyd, Dan
    Linköping University, The Institute of Technology. Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics.
    Caidahl, K.
    Caidahl, K..
    Net Pressure Gradients in Aortic Prosthetic Valves can be Estimated by Doppler2003In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 16, no 8, p. 858-866Article in journal (Refereed)
    Abstract [en]

    Background: In aortic prosthetic valves, both the Doppler-estimated gradients and orifice areas are misleading in the assessment of hemodynamic performance. The parameter of major interest is the net pressure gradient after pressure recovery (PR). We, therefore, investigated, in vitro, our ability to predict the net pressure gradient and applied the formulas in a representative patient population with 2 different valve designs. Methods: We studied the St Jude Medical (SJM) standard valve (size 19-27) and SJM Biocor (size 21-27) in an in vitro steady-flow model with simultaneous Doppler-estimated pressure and catheter pressure measurements. Using echocardiography, we also studied patients who received the SJM (n = 66) and SJM Biocor (n = 45). Results: In the SJM, we observed PR both within the prosthesis and aorta, whereas in the SJM Biocor, PR was only present in the aorta. We estimated the PR within the valve and within the aorta separately from echocardiographic in vitro data, combining a regression equation (valve) with an equation on the basis of fluid mechanics theory (aorta). The difference between estimated and catheter-obtained net gradients (mean ± SD) was 0.6 ± 1.6 mm Hg in the SJM and - 0.2 ± 1.9 mm Hg in the SJM Biocor. When these equations were applied in vivo, we found that PR had an overall value of 57 ± 7% of the peak Doppler gradient in the SJM and 33 ± 9% in the SJM Biocor. Conclusions: The in vitro results indicate that it is possible to predict the net pressure gradient by Doppler in bileaflet and stented biologic valves. Our data indicate that important PR is also present in stented biologic valves.

  • 22.
    Björck, Hanna M.
    et al.
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences.
    Renner, Johan
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Maleki, Shohreh
    Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institute, Sweden.
    Nilsson, Siv F.E.
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Kihlberg, Johan
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Folkersen, Lasse
    Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institute, Sweden.
    Karlsson, Matts
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Ebbers, Tino
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Eriksson, Per
    Atherosclerosis Research Unit, Center for Molecular Medicine, Department of Medicine, Karolinska Institute, Sweden.
    Länne, Toste
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Characterization of Shear-Sensitive Genes in the NormalRat Aorta Identifies Hand2 as a Major Flow-ResponsiveTranscription Factor2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 12Article in journal (Refereed)
    Abstract [en]

    Objective: Shear forces play a key role in the maintenance of vessel wall integrity. Current understanding regarding shear-dependent gene expression is mainly based on in vitro or in vivo observations with experimentally deranged shear, hence reflecting acute molecular events in relation to flow. Our objective was to determine wall shear stress (WSS) in the rat aorta and study flow-dependent vessel wall biology under physiological conditions.

    Methods and Results: Animal-specific aortic WSS magnitude and vector direction were estimated using computational fluid dynamic simulation based on aortic geometry and flow information acquired by MRI. Two distinct flow pattern regions were identified in the normal rat aorta; the distal part of the inner curvature being exposed to low WSS and a non-uniform vector direction, and a region along the outer curvature being subjected to markedly higher levels of WSS and a uniform vector direction. Microarray analysis revealed a strong differential expression between the flow regions, particularly associated with transcriptional regulation. In particular, several genes related to Ca2+-signalling, inflammation, proliferation and oxidative stress were among the most highly differentially expressed.

    Conclusions: Microarray analysis validated the CFD-defined WSS regions in the rat aorta, and several novel flow-dependent genes were identified. The importance of these genes in relation to atherosusceptibility needs further investigation.

  • 23.
    Blomstrand, Peter
    et al.
    County Hospital Ryhov, Sweden .
    Ekedahl, Susanne
    Rosenlund Primary Care Unit, Sweden .
    Schmekel, Birgitta
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Bronchial Responsiveness to Dry Air Hyperventilation in Smokers May Predict Decline in Airway Status Using Indirect Methods2013In: Lung, ISSN 0341-2040, E-ISSN 1432-1750, Vol. 191, no 2, p. 183-190Article in journal (Refereed)
    Abstract [en]

    Disabling respiratory symptoms and rapid decline of lung function may occur in susceptible tobacco smokers. Bronchial hyperresponsiveness (BHR) elicited by direct challenge methods predicts worse lung function outcomes. The aim of this study was to evaluate whether BHR to isocapnic hyperventilation of dry air (IHDA) was associated with rapid deterioration in airway status and respiratory symptoms. less thanbrgreater than less thanbrgreater thanOne hundred twenty-eight smokers and 26 age- and sex-matched healthy individuals with no history of smoking were investigated. All subjects completed a questionnaire. Spirometry and impulse oscillometry (IOS) measurements were recorded before and after 4 min of IHDA. The tests were repeated after 3 years in 102 smokers and 11 controls. less thanbrgreater than less thanbrgreater thanEighty-five smokers (66 %) responded to the challenge with a a parts per thousand yen2.4-Hz increase in resonant frequency (F (res)), the cutoff limit defining BHR, as recorded by IOS. They had higher F (res) at baseline compared to nonresponding smokers [12.8 +/- A 3.2 vs. 11.5 +/- A 3.4 Hz (p andlt; 0.05)] and lower FEV1 [83 +/- A 13 vs. 89 +/- A 13 % predicted (p andlt; 0.05)]. Multivariable logistic regression analysis indicated that wheezing (odds ratio = 3.7, p andlt; 0.01) and coughing (odds ratio = 8.1, p andlt; 0.05) were significantly associated with hyperresponsiveness. An increase in F (res) was recorded after 3 years in responding smokers but not in nonresponders or controls. The difference remained when subjects with COPD were excluded. less thanbrgreater than less thanbrgreater thanThe proportion of hyperresponsive smokers was unexpectedly high and there was a close association between wheezing and coughing and BHR. Only BHR could discriminate smokers with rapid deterioration of airway status from others.

  • 24.
    Blomstrand, Peter
    et al.
    County Hospital Ryhov, Jököping, Sweden.
    Maret, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Ohlsson, Jan
    County Hospital Ryhov, Jönköping, Sweden.
    Scheike, Morten
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Karlsson, Jan-Erik
    County Hospital Ryhov, Jönköping, Sweden.
    Säfström, Kåge
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Swahn, Eva
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Pulsed tissue Doppler imaging for the detection of myocardial ischaemia, a comparison with myocardial perfusion SPECT2004In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 24, no 5, p. 289-295Article in journal (Refereed)
    Abstract [en]

    In order to compare the diagnostic ability of pulsed tissue Doppler and myocardial perfusion Single Photon Emission Computed Tomography (SPECT) in patients with a history of unstable coronary artery disease, CAD, 26 patients, 22 men and four women, age 47-76 years, were investigated in a prospective study, 5-10 day after an episode of unstable angina. Tissue Doppler and two-dimensional echocardiography were performed during dobutamine stress testing and myocardial scintigraphy after bicycle exercise and at rest. Patients with a normal SPECT had higher peak systolic velocity during dobutamine infusion, 18.9 +/- 4.1 cm s(-1), than patients with ischaemia, 12.2 +/- 3.8 cm s(-1) (P<0.001) or scar, 8.8 +/- 3.0 cm s(-1) (P<0.01). In a territorial analysis the difference in peak systolic velocity between areas with a normal and abnormal SPECT was less apparent. Failure to achieve >/=13 cm s(-1) in mean-peak systolic velocity was the most accurate criterion for detection of significant CAD on SPECT. We conclude that pulsed tissue Doppler can be used for objective quantification of left ventricular wall motion during dobutamine stress testing and for identification of patients with CAD on SPECT but not for identification of regional ischaemia.

  • 25.
    Blystad, Ida
    et al.
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping.
    Warntjes, Jan Bertus Marcel
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Smedby, Örjan
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Diagnostics, Department of Radiology in Linköping.
    Landtblom, Anne-Marie
    Linköping University, Department of Clinical and Experimental Medicine, Neurology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology. Linköping University, Center for Medical Image Science and Visualization, CMIV.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL.
    SyntheticMRI compared with conventional MRI of the brain in a clinical setting: a pilot study, ESMRMB 2012, Lisbon, Portugal.2012Conference paper (Other academic)
  • 26.
    Blystad, Ida
    et al.
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Warntjes, Jan Bertus Marcel
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Smedby, Örjan
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Radiology in Linköping.
    Landtblom, Anne-Marie
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Clinical and Experimental Medicine, Neurology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics.
    Larsson, Elna-Marie
    Uppsala University, Sweden .
    Synthetic MRI of the brain in a clinical setting2012In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 53, no 10, p. 1158-1163Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    Conventional magnetic resonance imaging (MRI) has relatively long scan times for routine examinations, and the signal intensity of the images is related to the specific MR scanner settings. Due to scanner imperfections and automatic optimizations, it is impossible to compare images in terms of absolute image intensity. Synthetic MRI, a method to generate conventional images based on MR quantification, potentially both decreases examination time and enables quantitative measurements.

    PURPOSE:

    To evaluate synthetic MRI of the brain in a clinical setting by assessment of the contrast, the contrast-to-noise ratio (CNR), and the diagnostic quality compared with conventional MR images.

    MATERIAL AND METHODS:

    Twenty-two patients had synthetic imaging added to their clinical MR examination. In each patient, 12 regions of interest were placed in the brain images to measure contrast and CNR. Furthermore, general image quality, probable diagnosis, and lesion conspicuity were investigated.

    RESULTS:

    Synthetic T1-weighted turbo spin echo and T2-weighted turbo spin echo images had higher contrast but also a higher level of noise, resulting in a similar CNR compared with conventional images. Synthetic T2-weighted FLAIR images had lower contrast and a higher level of noise, which led to a lower CNR. Synthetic images were generally assessed to be of inferior image quality, but agreed with the clinical diagnosis to the same extent as the conventional images. Lesion conspicuity was higher in the synthetic T1-weighted images, which also had a better agreement with the clinical diagnoses than the conventional T1-weighted images.

    CONCLUSION:

    Synthetic MR can potentially shorten the MR examination time. Even though the image quality is perceived to be inferior, synthetic images agreed with the clinical diagnosis to the same extent as the conventional images in this study.

  • 27.
    Blystad, Ida
    et al.
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Östergötlands Läns Landsting, Center for Diagnostics, Department of Radiology in Linköping. Linköping University, Department of Medical and Health Sciences, Radiology.
    Warntjes, Marcel
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Helmersson, Teresa
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Lundberg, Peter
    Linköping University, Center for Medical Image Science and Visualization (CMIV). Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics. Östergötlands Läns Landsting, Center for Diagnostics, Department of Radiology in Linköping.
    Contrast assessment of Synthetic Magnetic Resonance Imaging in clinical practice2011Conference paper (Refereed)
  • 28.
    Bolger, Ann F
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Heiberg, Einar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Dyverfeldt, Petter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Carlsson, Mats
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Medical Informatics.
    Johansson, P
    Markenroth, K
    Sigfridsson, Andreas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Engvall, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ebbers, Tino
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Arheden, H
    Tredimensionellt MR-blodflöde och diastolisk kinetisk energi kvantiferat med magnetisk resonanstomografi efter kirurgisk vänsterkammarrekonstruktion. Ny teknik för utvärdering av kammarfunktion.2007In: Riksstämman,2007, 2007Conference paper (Other academic)
  • 29. Borjesson, Mats
    et al.
    Dellborg, Mikael
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Untitled2006In: Scandinavian Journal of Medicine and Science in Sports, ISSN 0905-7188, E-ISSN 1600-0838, Vol. 16, no 5, p. 376-377Other (Other academic)
  • 30.
    Brodtkorb, Thor-Henrik
    et al.
    Linköping University, Department of Medicine and Health Sciences, Health Technology Assessment. Linköping University, The Institute of Technology.
    Henriksson, Martin
    Health Economics Department, AstraZeneca, Södertälje, Sweden.
    Nylander, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Screening for hypertrophic cardiomyopathy in young athletes: A cost-effectiveness analysisManuscript (preprint) (Other academic)
    Abstract [en]

    Background: Screening to prevent sudden cardiac death among young athletes has been debated for some time and several countries have already introduced pre-participation cardiovascular screening to identify sports active individuals at risk. Although, hypertrophic cardiomyopathy (HCM) is the most common underlying disease that is documented to be detectable by screening the cost-effectiveness of such a screening strategy is still unclear.

    Methods: A screening program to detect HCM in young athletes was compared to a non screening strategy. Prevalence of HCM, mortality risks and test characteristics were estimated from published sources and formal expert elicitation. These estimates were incorporated in a decision analytic model to estimate costs and health outcomes, expressed in life years and quality adjusted life years (QALYs), over a lifetime perspective.

    Results: The screening strategy was associated with a mean incremental cost of €93 and a mean incremental gain of 0.0005 life years, yielding a cost per life year gained of €196 205. Taking quality of life into account, the screening strategy was associated with a loss of 0.034 QALY.

    Conclusions: The study shows that screening young athletes for hypertrophic cardiomyopathy is not likely to yield survival benefits at a cost normally considered to be cost-effective and if quality of life is considered in the analysis screening is associated with higher costs and a loss of QALYs. Thus, based on the present findings a strategy of screening young athletes for hypertrophic cardiomyopathy is unlikely to be cost effective.

  • 31.
    Brolin, Gustav
    et al.
    Department of Medical Radiation Physics, Lund University, Sweden.
    Granerus, Göran
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Olsson, Anna
    Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences.
    Edenbrandt, Lars
    Department of Clinical Sciences, Malmö, Lund University, Sweden.
    Ljungberg, Michael
    Department of Medical Radiation Physics, Lund University, Sweden.
    A new Method for Monte Carlo Simulations of Dynamic Scintillation Camera Imaging: 99mTc MAG3 Renography Studies2012Conference paper (Other academic)
  • 32.
    Carhall, C
    et al.
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Eriksson, Jonatan
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Dyverfeldt, Petter
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Ebbers, Tino
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Bolger, A
    University of California San Francisco.
    Pre-systolic preparation for left ventricular ejection is impaired in heart failure in EUROPEAN HEART JOURNAL, vol 31, issue , pp 726-7272010In: EUROPEAN HEART JOURNAL, Oxford University Press , 2010, Vol. 31, p. 726-727Conference paper (Refereed)
    Abstract [en]

    n/a

  • 33. Carlhall, C.
    et al.
    Wigström, Lars
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Heiberg, Einar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Karlsson, Matts
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Biomedical Modelling and Simulation .
    Bolger, A.F.
    Department of Medicine, Division of Cardiology, University of California, San Francisco, CA, United States.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Reply [2]2006In: American Journal of Physiology. Heart and Circulatory Physiology, ISSN 0363-6135, E-ISSN 1522-1539, Vol. 291, no 5Other (Other academic)
    Abstract [en]

    [No abstract available]

  • 34.
    Carlhäll, Carljohan
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Bolger, Ann
    University of California San Francisco.
    Passing Strange Flow in the Failing Ventricle2010In: CIRCULATION-HEART FAILURE, ISSN 1941-3289, Vol. 3, no 2, p. 326-331Article in journal (Refereed)
    Abstract [en]

    n/a

  • 35.
    Carlhäll, Carljohan
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Lindström, Lena
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology .
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Atrioventricular plane displacement correlates closely to circulatory dimensions but not to ejection fraction in normal subjects2001In: Journal of the American College of Cardiology, ISSN 0735-1097, E-ISSN 1558-3597, Vol. 37, no 2, p. 388A-388AConference paper (Other academic)
  • 36.
    Carlhäll, Carljohan
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Nguyen, Tom C.
    Itoh, Akinobu
    Ennis, Daniel B.
    Bothe, Wolfgang
    Liang, David
    Stanford Univ, Sch Med, Div Cardiovasc Med, Stanford, CA 94305 USA.
    Ingels, Neil B.
    Palo Alto Med Fdn, Res Inst, Palo Alto, CA 94301 USA.
    Miller, D. Craig
    Stanford Univ, Sch Med, Falk Cardiovasc Res Ctr, Dept Cardiothorac Surg, Stanford, CA 94305 USA.
    Alterations in transmural myocardial strain - An early marker of left ventricular dysfunction in mitral regurgitation?2008In: Circulation, ISSN 0009-7322, E-ISSN 1524-4539, Vol. 118, no 14, p. S256-S262Article in journal (Refereed)
    Abstract [en]

    Background-In asymptomatic patients with severe isolated mitral regurgitation (MR), identifying the onset of early left ventricular (LV) dysfunction can guide the timing of surgical intervention. We hypothesized that changes in LV transmural myocardial strain represent an early marker of LV dysfunction in an ovine chronic MR model. Methods and Results-Sheep were randomized to control (CTRL, n = 8) or experimental (EXP, n = 12) groups. In EXP, a 3.5-or 4.8-mm hole was created in the posterior mitral leaflet to generate "pure" MR. Transmural beadsets were inserted into the lateral and anterior LV wall to radiographically measure 3-dimensional transmural strains during systole and diastolic filling, at 1 and 12 weeks postoperatively. MR grade was higher in EXP than CTRL at 1 and 12 weeks (3.0 [2-4] versus 0.5 [0-2], 3.0 [1-4] versus 0.5 [0-1], respectively, both P < 0.001). At 12 weeks, LV mass index was greater in EXP than CTRL (201 +/- 18 versus 173 +/- 17 g/m(2), P < 0.01). LVEDVI increased in EXP from 1 to 12 weeks (P = 0.015). Between the 1 and 12 week values, the change in BNP (-4.5 +/- 4.4 versus-3.0 +/- 3.6 pmol/L), PRSW (9 +/- 13 versus 23 +/- 18 mm Hg), tau (-3 +/- 11 versus-4 +/- 7 ms), and systolic strains was similar between EXP and CTRL. The changes in longitudinal diastolic filling strains between 1 and 12 weeks, however, were greater in EXP versus CTRL in the subendocardium (lateral:-0.08 +/- 0.05 versus 0.02 +/- 0.14, anterior:-0.10 +/- 0.05 versus-0.02 +/- 0.07, both P < 0.01). Conclusions-Twelve weeks of ovine "pure" MR caused LV remodeling with early changes in LV function detected by alterations in transmural myocardial strain, but not by changes in BNP, PRSW, or tau.

  • 37.
    Chew, Michelle
    et al.
    Malmö University.
    Brandberg, Joakim
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Janerot Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Sloth, Erik
    Aarhus University Hospital.
    Hasenkam, J. Michael
    Aarhus University Hospital.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Colour Doppler flow measurements using surface integration of velocity vectors (SIVV): Effect of colour flow gain, pulse repetition frequency and number of imaging planes2008In: Open medical imaging journal, ISSN 1874-3471, Vol. 2, p. 56-61Article in journal (Refereed)
  • 38.
    Dahlén, Elsa M
    et al.
    Linköping University, Department of Medicine and Health Sciences, General Practice. Linköping University, Faculty of Health Sciences.
    Länne, Toste
    Linköping University, Department of Medicine and Health Sciences, Physiology . Linköping University, Department of Medicine and Health Sciences, Vascular surgery . Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery. Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Lindström, T
    Linköping University, Department of Medicine and Health Sciences, Internal Medicine . Östergötlands Läns Landsting, Centre for Medicine, Department of Endocrinology and Gastroenterology UHL. Linköping University, Faculty of Health Sciences.
    Grodzinsky, Ewa
    Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland. Linköping University, Department of Medicine and Health Sciences, General Practice. Linköping University, Faculty of Health Sciences.
    Nyström, Fredrik
    Linköping University, Department of Medicine and Health Sciences, Internal Medicine . Östergötlands Läns Landsting, Centre for Medicine, Department of Endocrinology and Gastroenterology UHL. Linköping University, Faculty of Health Sciences.
    Östgren, Carl Johan
    Linköping University, Department of Medicine and Health Sciences, General Practice. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in the West of Östergötland, West County Primary Health Care.
    Complications Carotid intima-media thickness and apolipoprotein B/apolipoprotein A-I ratio in middle-aged patients with Type 2 diabetes2009In: Diabetic Medicine, ISSN 0742-3071, E-ISSN 1464-5491, Vol. 26, no 4, p. 384-390Article in journal (Refereed)
    Abstract [en]

    AIMS: To explore the association between carotid intima-media thickness (IMT) and the apolipoprotein B (apoB)/apolipoprotein A-I (apoA-I) ratio compared with conventional lipids in middle-aged patients with Type 2 diabetes. METHODS: We analysed data from 247 patients with Type 2 diabetes, aged 55-66 years, in the Cardiovascular Risk factors in Patients with Diabetes-a Prospective study in Primary care (CARDIPP-1) study. Primary care nurses measured blood pressure and anthropometric characteristics. Blood samples were taken for laboratory analyses. The carotid IMT was determined by ultrasonography at the University Hospital in Linköping and at the County Hospital Ryhov, Jönköping, Sweden. RESULTS: The ApoB/apoA-I ratio (r = 0.207, P = 0.001), apoB (r = 0.166, P = 0.009) and non-high-density lipoprotein cholesterol (non-HDL-c) (r = 0.129, P = 0.046) correlated with IMT. Conventional lipids, high-sensitivity C-reactive protein (hsCRP), glycated haemoglobin (HbA(1c)) and systolic blood pressure were not significantly correlated to IMT. A stepwise logistic regression analysis was conducted with IMT as the dependent variable and the apoB/apoA-I ratio, HbA(1c), hsCRP, low-density lipoprotein cholesterol (LDL-c), total cholesterol, non-HDL-c and treatment with statins as independent variables. Following adjustment for age and gender, only the apoB/apoA-I ratio remained significantly associated with IMT (odds ratio 4.3, 95% confidence intervals 1.7-10.8, P = 0.002). CONCLUSIONS: We conclude that there was a significant association between the apoB/apoA-I ratio and IMT in middle-aged patients with Type 2 diabetes. The association was independent of conventional lipids, hsCRP, glycaemic control and use of statins.

  • 39.
    Davidsson, Anette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Exhaled Breath Condensate in Obstructive Lung Diseases: A Methodological study2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Asthma and chronic obstructive pulmonary disease (COPD) are two common inflammatory airway diseases characterized by airway inflammation and mucus hypersecretion. Prediction of the outcome of these diseases may not be performed and the need for non-invasive diagnostic tools capable of identifying inflammation in asthma and COPD becomes therefore obvious. Validation, sensitivity and specificity of most non-invasive methods to detect and monitor inflammatory responses in airways are poor and there is a great need to identify and standardize less invasive, or non-invasive methods for investigation of airway inflammation.

    Epithelial lining fluid (ELF) covers the airway surface and contains soluble and insoluble inflammatory cell products and plasma proteins originating and passively transferred from the underlying tissue. Airborne aerosol particles containing ELF saturated with water may be recovered in exhaled air by allowing the air to pass a cold surface, creating exhaled breath condensate (EBC). EBC may then be analysed for various components of interest.

    The aims of this thesis were (1) to explore whether a certain profile of inflammatory cell markers in EBC, saliva or serum may be identified in patients with allergic asthma or COPD, (2) to evaluate the efficacy and reproducibility of a measurable marker in EBC using either of the two condensers ECoScreen or RTube and (3) to evaluate the value of chlorine concentrations in EBC as well as reproducibility of assessments of certain compounds in EBC.

    Material and methods: Thirty-six patients with asthma, 49 smokers or ex-smokers and 25 healthy volunteers participated in three clinical studies. In addition, efficacy, reproducibility and comparison of the two condensers were studied in an ex vivo set up using aerosols of solutions of saline, myeloperoxidase (MPO) or human neutrophil lipocalin (HNL). Aerosol boluses were transferred by means of a servo ventilator to either of the two condensers. Concentrations of chlorine (presumed to be a marker of mucous secretion) in EBC or saliva were analyzed by means of a sensitive coulometric technique (AOX). The inflammatory cell markers histamine, MPO, HNL, lysozyme, cysteinyl-leukotrienes (CysLT) and eosinophil cationic protein (ECP) were analysed in EBC, saliva and/or serum by means of ELISA, RIA, EIA or immunochemical fluorescence methods, respectively. Lung function tests, including diffusion capacity were measured by standard techniques according to clinical routines.

    Results and Conclusions: Chlorine measurements served as the main tool in our tests and intra-assay variability <10% was recorded. However, flow dependency, temperature dependency, substance dependency and concentration dependency characterized yields of EBC. Despite acceptable analytical precision, low concentration levels of inflammation markers, biological variability and occasionally contamination with saliva mean that the feasibility of the EBC method is limited. Despite biological variability, concentrations of chlorine in EBC were significantly higher during than after a mild pollen season, suggesting that chlorine concentrations in EBC are a sensitive marker of allergic airway inflammation. A vast number of confounding factors made interpretations of EBC data obtained from COPD and non-COPD patients difficult and traditional diagnostic tools, such as diffusion capacity (DLCO) and serum lysozyme appeared to best discriminate between COPD and non-COPD.

    List of papers
    1. Quantitative Assessment and Repeatability of Chlorine in Exhaled Breath Condensate: Comparison of Two Types of Condensators
    Open this publication in new window or tab >>Quantitative Assessment and Repeatability of Chlorine in Exhaled Breath Condensate: Comparison of Two Types of Condensators
    2005 (English)In: Respiration, ISSN 0025-7931, E-ISSN 1423-0356, Vol. 72, no 5, p. 529-536Article in journal (Refereed) Published
    Abstract [en]

    Background: Airway condition is presumably reflected in epithelial lining fluid (ELF). Exhaled breath condensate (EBC) has been used as a surrogate marker of the composition of ELF.

    Objectives: This study aimed at assessing the technical repeatability of chlorine measurements in EBC and comparing two separate condensators (Ecoscreen® and R Tube) regarding recovery and repeatability. Furthermore, the association between condensate recoveries and variations in the airway status were scrutinized.

    Methods: EBC was collected using two condensators from 10 healthy volunteers. In addition, 13 asthmatic patients produced EBC with or without an added resistance of 5 cm H2O (Res5), applied to the outflow tract of Ecoscreen. All tests were done in random order. Chlorine levels (analyzed by a coulometric technique) in EBC served as a tool for investigation.

    Results: Chlorine was measurable in all samples. The coefficient of repeatability of chlorine measurements was <10%. Chlorine levels were higher in EBC obtained from R Tube (p < 0.001), and differences in recoveries and variability in chlorine levels were presumably related to technical differences in the condensators and not to the repeatability of chlorine measurements per se. Air-flow-dependent chlorine levels were obtained from healthy volunteers. Application of Res5, recruiting additional alveoli, resulted in increased recovery of the EBC volume, but not of chlorine, from those that had the most pronounced airway obstruction (p = 0.05).

    Conclusion: We conclude that by employing a sensitive analysis technique, chlorine is repeatedly measurable in EBC. We suggest that the bulk of chlorine in EBC originates from large airways and not from the alveolar area. Both condensators were comparable regarding repeatability but differed regarding chlorine recover

    Keyword
    Asthma, Chlorine, Exhaled breath condensate, Repeatability, Volunteers
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-16289 (URN)10.1159/000087679 (DOI)
    Available from: 2009-01-13 Created: 2009-01-13 Last updated: 2017-12-14Bibliographically approved
    2. Chlorine in Breath Condensate: A Measure of Airway Affection in Pollinosis?
    Open this publication in new window or tab >>Chlorine in Breath Condensate: A Measure of Airway Affection in Pollinosis?
    2007 (English)In: Respiration, ISSN 0025-7931, E-ISSN 1423-0356, Vol. 74, no 2, p. 184-191Article in journal (Refereed) Published
    Abstract [en]

    Background: Infiltration of inflammatory cells in bronchial mucosa and glandular hypersecretion are hallmarks of asthma. It has been postulated that exhaled breath condensate (EBC) mirrors events in epithelial lining fluid of airways, such as presence of local inflammation as well as glandular hypersecretion. It is also well known that eosinophil cationic protein (ECP) and cysteinyl-leukotrienes (cys-LT) are released by circulating inflammatory cells when triggered by antigen stimulation in asthma patients.

    Objectives: The aim of this study was to evaluate whether chlorine and/or cys-LT in EBC would reflect changes of exposure of airborne pollen in patients with asthma.

    Methods: EBC and serum were collected from 23 patients with allergic asthma during a pollen season and repeated 5 months later during a period with no aeroallergens. Chlorine was measured by means of a sensitive coulometric technique and cys-LT by an EIA technique. Serum ECP was measured and lung function tests were performed and symptoms noted during both occasions.

    Results: Significantly higher concentrations of chlorine in EBC (p = 0.007) and ECP in serum (p = 0.003) were found during the pollen season compared to post-season. Chlorine levels tended to be higher in patients who reported of chest symptoms compared to those who denied symptoms during the pollen season (p = 0.06). Areas under the receiver-operated characteristic curves (AUCROC) were compared and similar discriminative power to identify exacerbations of asthma was recorded by chlorine in EBC (range 0.67-0.78) and ECP in serum (range 0.64-0.78).

    Conclusion: It is concluded that chlorine in EBC and ECP in serum decreased significantly post-season, and this is suggested to mirror the decrement in airborne antigen. It is furthermore proposed that chlorine in EBC and ECP in serum tend to have a similar capacity to identify seasonal variations in airborne pollen in patients with asthma.

    Place, publisher, year, edition, pages
    Karger, 2007
    Keyword
    Pollen season, Allergic asthma, Exhaled breath condensate, Serum eosinophil cationic protein, Chlorine
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-16291 (URN)10.1159/000091300 (DOI)000244565600010 ()
    Available from: 2009-01-13 Created: 2009-01-13 Last updated: 2017-12-14Bibliographically approved
    3. Efficacy of Two Breath Condensers: An in Vitro Comparative Study
    Open this publication in new window or tab >>Efficacy of Two Breath Condensers: An in Vitro Comparative Study
    2008 (English)Article in journal (Refereed) Submitted
    Abstract [en]

    Examination of exhaled breath condensate (EBC) has been suggested to give information about inflammatory airway diseases.

    The aim of the present study was to compare efficacy and variability in gain of two commercially available condensers, ECoScreen® [E] and RTube [R] in an in vitro experimental set up.

    Methods: Test-fluids containing myeloperoxidase (MPO) or human neutrophil lipocalin (HNL) in addition to saline and bovine serum albumin (BSA) were nebulized. The aerosol was intermittently driven forward by a servoventilator fed by room tempered air, to reach the condenser. Two different concentrations of saline were also dispensed via the same equipment. Analyses of MPO, HNL and chlorine were done by means of ELISA, RIA or a modified adsorbed organic halogen technique (AOX), respectively.

    Results: Significantly higher volumes were recovered by ECoScreen than by RTube during 20-minutes experiments (p<0.001) but not in ten-minute experiments (p>0.05). Based on changes of source concentrations in the nebulizer cup, resulting from nebulization per se, recoveries of HNL tended to be higher by E than by R (p<0.05). In contrast there were no significant differences between condensers in recoveries of MPO or chlorine. The spread of data was wide regarding all tested compounds and of similar degree for both condensers, despite acceptable inter-assay coefficients of variations of all analyses.

    Conclusion: Condensing efficacy tended to be larger using E than R but there was a large variability in results from both condensers. Individual biomolecules may have their specific characteristics, and this must be taken into consideration when planning studies on EBC. We suggest that further methodological studies of the EBC method are warranted.

    Keyword
    Chlorine, HNL, MPO, Exhaled Breath Condensate, efficacy
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-16292 (URN)
    Available from: 2009-01-13 Created: 2009-01-13 Last updated: 2009-08-17Bibliographically approved
    4. Can we predict development of COPD?
    Open this publication in new window or tab >>Can we predict development of COPD?
    2008 (English)Article in journal (Refereed) Submitted
    Abstract [en]

    Background: Cigarette smoking is one of the main causes of chronic obstructive pulmonarydisease (COPD). Chronic inflammation of airways may start years before manifestation ofclinical symptoms, thus early identification of smokers at risk to develop COPD is crucial.Objectives: To evaluate if a single breath test for diffusion capacity (DLCO) or concentrationsof certain biomarkers in exhaled breath condensate (EBC), saliva or serum could identifysubjects with COPD or non-COPD smokers and ex-smokers supposed to be at risk to developCOPD, as suggested by rapid decline of forced expiratory volume in one second (FEV1) during afive year period.

    Methods: Twenty-nine symptom free smokers/ex-smokers, 16 smokers/ex-smokers with COPDand 19 matched healthy non-smoking volunteers were studied by means of spirometry, DLCO,and analyses of EBC, saliva and serum [chlorine, lysozyme, eosinophil cationic protein (ECP)and myeloperoxidase (MPO)]. Area under a receiver operated curve (AUCROC) was used toassess sensitivity and specificity of measurements to identify manifest or risk to get COPD.

    Results: Only DLCO could identify subjects with COPD or risk to develop COPD, as judged byAUCROC (0.85 or 0.75, respectively). Lower DLCO (p=0.003) and higher serum concentrationsof lysozyme (p=0.011) were recorded in those with COPD than non-COPD subjects.Furthermore, concentration of chlorine was higher in EBC from COPD subjects than fromhealthy volunteers (p<0.05). Except for chlorine, none of the remaining biomarkers weredetected in EBC and there was a vast variability of concentrations of biomarkers in saliva.

    Conclusion: DLCO was the most effective discriminator of COPD and rapid decline of lungfunction. Serum concentration of lysozyme was the second strongest discriminator, confirmingprevious findings on involvement of neutrophils in the disease process. The use of EBC as a toolto measure exhaled biomarkers involved in COPD is dubious due to large variability and lowconcentrations of markers in EBC.

    Keyword
    Exhaled Breath Condensate, serum, DLCO, COPD, lysozyme and chlorine
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-16293 (URN)
    Available from: 2009-01-13 Created: 2009-01-13 Last updated: 2009-09-18Bibliographically approved
  • 40.
    Davidsson, Anette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Histamine release from blood cells and serum ECP in patients with asthma, during and after a mild pollen season.2004In: The European Histamine Research Society, Köln, 2004, p. na-naConference paper (Refereed)
  • 41.
    Davidsson, Anette
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Naidu-Sjöswärd, Kerstin
    Linköping University, Department of Medicine and Health Sciences, Anesthesiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Intensive Care UHL.
    Lundman, Lena
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Schmekel, Birgitta
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Quantitative Assessment and Repeatability of Chlorine in Exhaled Breath Condensate: Comparison of Two Types of Condensators2005In: Respiration, ISSN 0025-7931, E-ISSN 1423-0356, Vol. 72, no 5, p. 529-536Article in journal (Refereed)
    Abstract [en]

    Background: Airway condition is presumably reflected in epithelial lining fluid (ELF). Exhaled breath condensate (EBC) has been used as a surrogate marker of the composition of ELF.

    Objectives: This study aimed at assessing the technical repeatability of chlorine measurements in EBC and comparing two separate condensators (Ecoscreen® and R Tube) regarding recovery and repeatability. Furthermore, the association between condensate recoveries and variations in the airway status were scrutinized.

    Methods: EBC was collected using two condensators from 10 healthy volunteers. In addition, 13 asthmatic patients produced EBC with or without an added resistance of 5 cm H2O (Res5), applied to the outflow tract of Ecoscreen. All tests were done in random order. Chlorine levels (analyzed by a coulometric technique) in EBC served as a tool for investigation.

    Results: Chlorine was measurable in all samples. The coefficient of repeatability of chlorine measurements was <10%. Chlorine levels were higher in EBC obtained from R Tube (p < 0.001), and differences in recoveries and variability in chlorine levels were presumably related to technical differences in the condensators and not to the repeatability of chlorine measurements per se. Air-flow-dependent chlorine levels were obtained from healthy volunteers. Application of Res5, recruiting additional alveoli, resulted in increased recovery of the EBC volume, but not of chlorine, from those that had the most pronounced airway obstruction (p = 0.05).

    Conclusion: We conclude that by employing a sensitive analysis technique, chlorine is repeatedly measurable in EBC. We suggest that the bulk of chlorine in EBC originates from large airways and not from the alveolar area. Both condensators were comparable regarding repeatability but differed regarding chlorine recover

  • 42.
    Davidsson, Anette
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Olsson, Eva
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Gustafsson, Agnetha
    Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL.
    Assessment of image quality for SPECT myocardial perfusion imaging with regard to reconstruction algorithms using visual grading regression.2012Conference paper (Other academic)
  • 43.
    Davidsson, Anette
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Physiology.
    Olsson, Eva
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology.
    Gustafsson, Agnetha
    Linköping University, Department of Medical and Health Sciences, Radiation Physics. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Surgery, Orthopaedics and Cancer Treatment, Department of Radiation Physics UHL.
    Visuell bedömning av bildkvalitet vid Myokardscintigrafi med avseende på rekonstruktionsalgoritmer2012Conference paper (Other academic)
  • 44.
    Davidsson, Anette
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Schmekel, Birgitta
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Efficacy of two breath condensers2010In: Journal of clinical laboratory analysis (Print), ISSN 0887-8013, E-ISSN 1098-2825, Vol. 24, no 4, p. 219-223Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Examination of Exhaled Breath Condensate has been suggested to give information about inflammatory airway diseases. OBJECTIVES: The aim was to compare efficacy and variability in gain of two commercially available exhaled breath condensers, ECoScreen and RTube in an in vitro set up. METHODS: Test fluids containing myeloperoxidase (MPO) or human neutrophil lipocalin (HNL) in addition to saline and bovine serum albumin were nebulized and aerosols were transferred by a servo ventilator to either of the two condensers. Analyses of MPO, HNL, or chlorine were done by means of ELISA, RIA, or a modified adsorbed organic halogen technique (AOX), respectively. RESULTS: Recoveries of HNL were higher when using ECoScreen than RTube (Pandlt;0.05). In contrast, there were no significant differences between the two condensers in recoveries of MPO or chlorine. The spread of data was wide regarding all tested compounds. CONCLUSION: Variability in gain was large and ECoScreen was more efficacious then RTube in condensing the tested solutes of HNL, but not those of MPO or chlorine.

  • 45.
    Davidsson, Anette
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Schmekel, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Histamine release from blood cells and serum ECP in patients with asthma, during and after a mild pollen season2005In: Inflammation Research, ISSN 1023-3830, E-ISSN 1420-908X, Vol. 54, p. S76-S77Article in journal (Refereed)
  • 46.
    Davidsson, Anette
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Stratelis, Georgios
    Linköping University, Department of Medicine and Health Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in the West of Östergötland, Primary Health Care Centres.
    Acevedo, F.
    Karolinska Institutet.
    Schmekel, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Can we predict development of COPD?2008Article in journal (Refereed)
    Abstract [en]

    Background: Cigarette smoking is one of the main causes of chronic obstructive pulmonarydisease (COPD). Chronic inflammation of airways may start years before manifestation ofclinical symptoms, thus early identification of smokers at risk to develop COPD is crucial.Objectives: To evaluate if a single breath test for diffusion capacity (DLCO) or concentrationsof certain biomarkers in exhaled breath condensate (EBC), saliva or serum could identifysubjects with COPD or non-COPD smokers and ex-smokers supposed to be at risk to developCOPD, as suggested by rapid decline of forced expiratory volume in one second (FEV1) during afive year period.

    Methods: Twenty-nine symptom free smokers/ex-smokers, 16 smokers/ex-smokers with COPDand 19 matched healthy non-smoking volunteers were studied by means of spirometry, DLCO,and analyses of EBC, saliva and serum [chlorine, lysozyme, eosinophil cationic protein (ECP)and myeloperoxidase (MPO)]. Area under a receiver operated curve (AUCROC) was used toassess sensitivity and specificity of measurements to identify manifest or risk to get COPD.

    Results: Only DLCO could identify subjects with COPD or risk to develop COPD, as judged byAUCROC (0.85 or 0.75, respectively). Lower DLCO (p=0.003) and higher serum concentrationsof lysozyme (p=0.011) were recorded in those with COPD than non-COPD subjects.Furthermore, concentration of chlorine was higher in EBC from COPD subjects than fromhealthy volunteers (p<0.05). Except for chlorine, none of the remaining biomarkers weredetected in EBC and there was a vast variability of concentrations of biomarkers in saliva.

    Conclusion: DLCO was the most effective discriminator of COPD and rapid decline of lungfunction. Serum concentration of lysozyme was the second strongest discriminator, confirmingprevious findings on involvement of neutrophils in the disease process. The use of EBC as a toolto measure exhaled biomarkers involved in COPD is dubious due to large variability and lowconcentrations of markers in EBC.

  • 47.
    Davidsson, Anette
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Söderström, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Naidu Sjöswärd, Kerstin
    Linköping University, Department of Medical and Health Sciences, Anesthesiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Intensive Care UHL.
    Schmekel, Birgitta
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Chlorine in Breath Condensate: A Measure of Airway Affection in Pollinosis?2007In: Respiration, ISSN 0025-7931, E-ISSN 1423-0356, Vol. 74, no 2, p. 184-191Article in journal (Refereed)
    Abstract [en]

    Background: Infiltration of inflammatory cells in bronchial mucosa and glandular hypersecretion are hallmarks of asthma. It has been postulated that exhaled breath condensate (EBC) mirrors events in epithelial lining fluid of airways, such as presence of local inflammation as well as glandular hypersecretion. It is also well known that eosinophil cationic protein (ECP) and cysteinyl-leukotrienes (cys-LT) are released by circulating inflammatory cells when triggered by antigen stimulation in asthma patients.

    Objectives: The aim of this study was to evaluate whether chlorine and/or cys-LT in EBC would reflect changes of exposure of airborne pollen in patients with asthma.

    Methods: EBC and serum were collected from 23 patients with allergic asthma during a pollen season and repeated 5 months later during a period with no aeroallergens. Chlorine was measured by means of a sensitive coulometric technique and cys-LT by an EIA technique. Serum ECP was measured and lung function tests were performed and symptoms noted during both occasions.

    Results: Significantly higher concentrations of chlorine in EBC (p = 0.007) and ECP in serum (p = 0.003) were found during the pollen season compared to post-season. Chlorine levels tended to be higher in patients who reported of chest symptoms compared to those who denied symptoms during the pollen season (p = 0.06). Areas under the receiver-operated characteristic curves (AUCROC) were compared and similar discriminative power to identify exacerbations of asthma was recorded by chlorine in EBC (range 0.67-0.78) and ECP in serum (range 0.64-0.78).

    Conclusion: It is concluded that chlorine in EBC and ECP in serum decreased significantly post-season, and this is suggested to mirror the decrement in airborne antigen. It is furthermore proposed that chlorine in EBC and ECP in serum tend to have a similar capacity to identify seasonal variations in airborne pollen in patients with asthma.

  • 48.
    Davidsson, Antette
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Naidu Sjöswärd, Kerstin
    Linköping University, Department of Medicine and Health Sciences, Anesthesiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Intensive Care UHL.
    Schmekel, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Efficacy of Two Breath Condensers: An in Vitro Comparative Study2008Article in journal (Refereed)
    Abstract [en]

    Examination of exhaled breath condensate (EBC) has been suggested to give information about inflammatory airway diseases.

    The aim of the present study was to compare efficacy and variability in gain of two commercially available condensers, ECoScreen® [E] and RTube [R] in an in vitro experimental set up.

    Methods: Test-fluids containing myeloperoxidase (MPO) or human neutrophil lipocalin (HNL) in addition to saline and bovine serum albumin (BSA) were nebulized. The aerosol was intermittently driven forward by a servoventilator fed by room tempered air, to reach the condenser. Two different concentrations of saline were also dispensed via the same equipment. Analyses of MPO, HNL and chlorine were done by means of ELISA, RIA or a modified adsorbed organic halogen technique (AOX), respectively.

    Results: Significantly higher volumes were recovered by ECoScreen than by RTube during 20-minutes experiments (p<0.001) but not in ten-minute experiments (p>0.05). Based on changes of source concentrations in the nebulizer cup, resulting from nebulization per se, recoveries of HNL tended to be higher by E than by R (p<0.05). In contrast there were no significant differences between condensers in recoveries of MPO or chlorine. The spread of data was wide regarding all tested compounds and of similar degree for both condensers, despite acceptable inter-assay coefficients of variations of all analyses.

    Conclusion: Condensing efficacy tended to be larger using E than R but there was a large variability in results from both condensers. Individual biomolecules may have their specific characteristics, and this must be taken into consideration when planning studies on EBC. We suggest that further methodological studies of the EBC method are warranted.

  • 49.
    Dyverfeldt, Petter
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics . Linköping University, The Institute of Technology.
    Extending MRI to the Quantification of Turbulence Intensity2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In cardiovascular medicine, the assessment of blood flow is fundamental to the understanding and detection of disease. Many pharmaceutical, interventional, and surgical treatments impact the flow. The primary purpose of the cardiovascular system is to drive, control and maintain blood flow to all parts of the body. In the normal cardiovascular system, fluid transport is maintained at high efficiency and the blood flow is essentially laminar. Disturbed and turbulent blood flow, on the other hand, appears to be present in many cardiovascular diseases and may contribute to their initiation and progression. Despite strong indications of an important interrelationship between flow and cardiovascular disease, medical imaging has lacked a non-invasive tool for the in vivo assessment of disturbed and turbulent flow. As a result, the extent and role of turbulence in the blood flow of humans have not yet been fully investigated.

    Magnetic resonance imaging (MRI) is a versatile tool for the non-invasive assessment of flow and has several important clinical and research applications, but might not yet have reached its full potential. Conventional MRI techniques for the assessment of flow are based on measurements of the mean velocity within an image voxel. The mean velocity corresponds to the first raw moment of the distribution of velocities within a voxel. An MRI framework for the quantification of any moment (mean, standard deviation, skew, etc.) of arbitrary velocity distributions is presented in this thesis.

    Disturbed and turbulent flows are characterized by velocity fluctuations that are superimposed on the mean velocity. The intensity of these velocity fluctuations can be quantified by their standard deviation, which is a commonly used measure of turbulence intensity. This thesis focuses on the development of a novel MRI method for the quantification of turbulence intensity. This method is mathematically derived and experimentally validated. Limitations and sources of error are investigated and guidelines for adequate application of MRI measurements of turbulence intensity are outlined. Furthermore, the method is adapted to the quantification of turbulence intensity in the pulsatile blood flow of humans and applied to a wide range of cardiovascular diseases. In these applications, elevated turbulence intensity was consistently detected in regions where highly disturbed flow was anticipated, and the effects of potential sources of errors were small.

    Diseased heart valves are often replaced with prosthetic heart valves, which, in spite of improved benefits and durability, continue to fall short of matching native flow patterns. In an in vitro setting, MRI was used to visualize and quantify turbulence intensity in the flow downstream from four common designs of prosthetic heart valves. Marked differences in the extent and degree of turbulence intensity were detected between the different valves.

    Mitral valve regurgitation is a common valve lesion associated with progressive left atrial and left ventricular remodelling, which may often require surgical correction to avoid irreversible ventricular dysfunction. The spatiotemporal dynamics of flow disturbances in mitral regurgitation were assessed based on measurements of flow patterns and turbulence intensity in a group of patients with significant regurgitation arising from similar valve lesions. Peak turbulence intensity occurred at the same time in all patients and the total turbulence intensity in the left atrium appeared closely related to the severity of regurgitation.

    MRI quantification of turbulence intensity has the potential to become a valuable tool in investigating the extent, timing and role of disturbed blood flow in the human cardiovascular system, as well as in the assessment of the effects of different therapeutic options in patients with vascular or valvular disorders.

    List of papers
    1. Quantification of intravoxel velocity standard deviation and turbulence intensity by generalizing phase-contrast MRI
    Open this publication in new window or tab >>Quantification of intravoxel velocity standard deviation and turbulence intensity by generalizing phase-contrast MRI
    2006 (English)In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 56, no 4, p. 850-858Article in journal (Refereed) Published
    Abstract [en]

    Turbulent flow, characterized by velocity fluctuations, is a contributing factor to the pathogenesis of several cardiovascular diseases. A clinical noninvasive tool for assessing turbulence is lacking, however. It is well known that the occurrence of multiple spin velocities within a voxel during the influence of a magnetic gradient moment causes signal loss in phase-contrast magnetic resonance imaging (PC-MRI). In this paper a mathematical derivation of an expression for computing the standard deviation (SD) of the blood flow velocity distribution within a voxel is presented. The SD is obtained from the magnitude of PC-MRI signals acquired with different first gradient moments. By exploiting the relation between the SD and turbulence intensity (TI), this method allows for quantitative studies of turbulence. For validation, the TI in an in vitro flow phantom was quantified, and the results compared favorably with previously published laser Doppler anemometry (LDA) results. This method has the potential to become an important tool for the noninvasive assessment of turbulence in the arterial tree.

    Keyword
    phase-contrast magnetic resonance imaging, turbulent flow, intravoxel velocity distribution, turbulence intensity, atherosclerosis
    National Category
    Medical and Health Sciences Physiology Fluid Mechanics and Acoustics Medical Laboratory and Measurements Technologies
    Identifiers
    urn:nbn:se:liu:diva-37249 (URN)10.1002/mrm.21022 (DOI)000240897000017 ()34073 (Local ID)34073 (Archive number)34073 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2018-01-13
    2. On MRI turbulence quantification
    Open this publication in new window or tab >>On MRI turbulence quantification
    Show others...
    2009 (English)In: Magnetic Resonance Imaging, ISSN 0730-725X, E-ISSN 1873-5894, Vol. 27, no 7, p. 913-922Article in journal (Refereed) Published
    Abstract [en]

    Turbulent flow, characterized by velocity fluctuations, accompanies many forms of cardiovascular disease and may contribute to their progression and hemodynamic consequences. Several studies have investigated the effects of turbulence on the magnetic resonance imaging (MRI) signal. Quantitative MRI turbulence measurements have recently been shown to have great potential for application both in human cardiovascular flow and in engineering flow. In this article, potential pitfalls and sources of error in MRI turbulence measurements are theoretically and numerically investigated. Data acquisition strategies suitable for turbulence quantification are outlined. The results show that the sensitivity of MRI turbulence measurements to intravoxel mean velocity variations is negligible, but that noise may degrade the estimates if the turbulence encoding parameter is set improperly. Different approaches for utilizing a given amount of scan time were shown to influence the dynamic range and the uncertainty in the turbulence estimates due to noise. The findings reported in this work may be valuable for both in vitro and in vivo studies employing MRI methods for turbulence quantification.

    Keyword
    Turbulence quantification, Turbulent flow, Phase-contrast magnetic resonance imaging, Constriction, Numerical flow phantom
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-20746 (URN)10.1016/j.mri.2009.05.004 (DOI)000269613000004 ()
    Note

    Original Publication: Petter Dyverfeldt, Roland Gårdhagen, Andreas Sigfridsson, Matts Karlsson and Tino Ebbers, On MRI turbulence quantification, 2009, MAGNETIC RESONANCE IMAGING, (27), 7, 913-922. http://dx.doi.org/10.1016/j.mri.2009.05.004 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/

    Available from: 2009-09-18 Created: 2009-09-18 Last updated: 2017-12-13
    3. Assessment of fluctuating velocities in disturbed cardiovascular blood flow: in vivo feasibility of generalized phase-contrast MRI
    Open this publication in new window or tab >>Assessment of fluctuating velocities in disturbed cardiovascular blood flow: in vivo feasibility of generalized phase-contrast MRI
    Show others...
    2008 (English)In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 28, no 3, p. 655-663Article in journal (Refereed) Published
    Abstract [en]

    Purpose

    To evaluate the feasibility of generalized phase-contrast magnetic resonance imaging (PC-MRI) for the noninvasive assessment of fluctuating velocities in cardiovascular blood flow.

    Materials and Methods

    Multidimensional PC-MRI was used in a generalized manner to map mean flow velocities and intravoxel velocity standard deviation (IVSD) values in one healthy aorta and in three patients with different cardiovascular diseases. The acquired data were used to assess the kinetic energy of both the mean (MKE) and the fluctuating (TKE) velocity field.

    Results

    In all of the subjects, both mean and fluctuating flow data were successfully acquired. The highest TKE values in the patients were found at sites characterized by abnormal flow conditions. No regional increase in TKE was found in the normal aorta.

    Conclusion

    PC-MRI IVSD mapping is able to detect flow abnormalities in a variety of human cardiovascular conditions and shows promise for the quantitative assessment of turbulence. This approach may assist in clarifying the role of disturbed hemodynamics in cardiovascular diseases.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-43135 (URN)10.1002/jmri.21475 (DOI)000259106900013 ()71980 (Local ID)71980 (Archive number)71980 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-12-13
    4. In Vitro Assessment of Flow Patterns and Turbulence Intensity in Prosthetic Heart Valves Using Generalized Phase-Contrast Magnetic Resonance Imaging
    Open this publication in new window or tab >>In Vitro Assessment of Flow Patterns and Turbulence Intensity in Prosthetic Heart Valves Using Generalized Phase-Contrast Magnetic Resonance Imaging
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Purpose: To assess in vitro the three-dimensional mean velocity field and the extent and degree of turbulenceintensity in different prosthetic heart valves using a generalization of phase-contrast magnetic resonance imaging(PC-MRI).

    Material and Methods: Four 27 mm aortic valves (Björk-Shiley Monostrut tilting-disc, St. Jude MedicalStandard bileaflet, Medtronic Mosaic stented and Freestyle stentless porcine valve) were tested under steadyinflow conditions in a Plexiglas phantom. Three-dimensional PC-MRI data were acquired to measure the meanvelocity field and the turbulent kinetic energy (TKE), a direction-independent measure of turbulence intensity.

    Results: Velocity and turbulence intensity estimates could be obtained up and downstream of the valves, exceptwhere metallic structure in the valves caused signal void. Distinct differences in the location, extent and peakvalues of velocity and turbulence intensity were observed between the valves tested. The maximum values ofTKE varied between the different valves: tilting disc, 100 J/m3; bileaflet, 115 J/m3; stented, 200 J/m3; stentless,145 J/m3.

    Conclusion: The turbulence intensity downstream from a prosthetic heart valve is dependent on the specificvalve design. Generalized PC-MRI can be used to quantify velocity and turbulence intensity downstream fromprosthetic heart valves, which may allow assessment of these aspects of prosthetic valvular function inpostoperative patients.

    Keyword
    Turbulence intensity, prosthetic heart valves, phase-contrast magnetic resonance imaging
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-53189 (URN)
    Available from: 2010-01-19 Created: 2010-01-19 Last updated: 2013-09-03Bibliographically approved
    5. Hemodynamic aspects of mitral regurgitation assessed by generalized phase-contrast MRI
    Open this publication in new window or tab >>Hemodynamic aspects of mitral regurgitation assessed by generalized phase-contrast MRI
    Show others...
    2011 (English)In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 33, no 3, p. 582-588Article in journal (Refereed) Published
    Abstract [en]

    Purpose: Mitral regurgitation creates a high velocity jet into the left atrium (LA), contributing both volume andpressure; we hypothesized that the severity of regurgitation would be reflected in the degree of LA flowdistortion.

    Material and Methods: Three-dimensional cine PC-MRI was applied to determine LA flow patterns andturbulent kinetic energy (TKE) in seven subjects (five patients with posterior mitral leaflet prolapse, two normalsubjects). In addition, the regurgitant volume and the time-velocity profiles in the pulmonary veins weremeasured.

    Results: The LA flow in the mitral regurgitation patients was highly disturbed with elevated values of TKE.Peak TKE occurred consistently at late systole. The total LA TKE was closely related to the regurgitant volume.LA flow patterns were characterized by a pronounced vortex in proximity to the regurgitant jet. In some patients,pronounced discordances were observed between individual pulmonary venous inflows, but these could not berelated to the direction of the flow jet or parameters describing global LA hemodynamics.

    Conclusion: PC-MRI permits investigations of atrial and pulmonary vein flow patterns and TKE in significantmitral regurgitation, reflecting the impact of the highly disturbed blood flow that accompanies this importantvalve disease.

    Place, publisher, year, edition, pages
    John Wiley and Sons, 2011
    Keyword
    Hemodynamics, mitral valve insufficiency, turbulent flow, phase-contrast magnetic resonance imaging, pulmonary veins, blood flow velocity
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-53190 (URN)10.1002/jmri.22407 (DOI)000287951100009 ()
    Available from: 2010-01-19 Created: 2010-01-19 Last updated: 2017-12-12
  • 50.
    Dyverfeldt, Petter
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Eriksson, Jonatan
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Sigfridsson, Andreas
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Escobar Kvitting, John-Peder
    Linköping University, Department of Medical and Health Sciences, Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Carlhäll, Carljohan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Engvall, Jan
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Bolger, Ann F.
    University of California San Francisco, San Francisco, California, USA.
    Ebbers, Tino
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Extending 4D Flow Visualization to the Human Right Ventricle2009In: Proceedings of International Society for Magnetic Resonance in Medicine: 17th Scientific Meeting 2009, International Society for Magnetic Resonance in Medicine , 2009, p. 3860-3860Conference paper (Refereed)
    Abstract [en]

    The right ventricle has an important role in cardiovascular disease. However, because of the complex geometry and the sensitivity to the respiratory cycle, imaging of the right ventricle is challenging. We investigated whether 3D cine phase-contrast MRI can provide data with sufficient accuracy for visualizations of the 4D blood flow in the right ventricle. Whole-heart 4D flow measurements with optimized imaging parameters and post-processing tools were made in healthy volunteers. Pathlines emitted from the right atrium could be traced through the right ventricle to the pulmonary artery without leaving the blood pool and thereby met our criteria for sufficient accuracy.

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