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  • 151.
    Karlsson, Matts
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Biomedical Modelling and Simulation .
    Engvall, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, 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.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Loyd, Dan
    Linköping University, The Institute of Technology. Linköping University, Department of Mechanical Engineering, Applied Thermodynamics and Fluid Mechanics.
    Orifice flow in stenotic and regurgitant valve lesions - Modelling and computer simulations1994In: Biofluid mechanics, Southhampton: Computational Mechanics Publications , 1994Chapter in book (Other academic)
  • 152. Kjellgren, K.
    et al.
    Silén, Charlotte
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Hård af Segerstad, Helene
    Linköping University, Faculty of Educational Sciences. Linköping University, Department of Behavioural Sciences, Studies in Adult, Popular and Higher Education.
    Utveckling av ett datorbaserat utvärderingsprogram1995In: NFPF konferens,1995, 1995Conference paper (Refereed)
  • 153.
    Knutsson, Hans
    et al.
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Andersson, Mats
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Wigström, Lars
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Borga, Magnus
    Linköping University, Department of Biomedical Engineering, Medical Informatics. Linköping University, The Institute of Technology. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Sigfridsson, Andreas
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Motion artifact reduction in MRI through generalized DFT2004In: Biomedical Imaging: Nano to Macro, 2004. IEEE International Symposium on, IEEE , 2004, p. 896-899 vol.1Conference paper (Refereed)
    Abstract [en]

    This paper presents a method that dramatically reduces artifacts caused by respiratory (and similar types of) patient motion in magnetic resonance imaging (MRI). The basis for the method is the observation that affine deformations of an object will correspond to a different but unique affine coordinate transform (plus phase shift) of the Fourier representation of the object. The resulting sample points will be irregularly distributed prohibiting the use of standard IFFT to reconstruct the object. The object can however be reconstructed through the use of a weighted regularized pseudo inverse. A standard pseudo inverse is, however, not possible due to excessive computational demands. For this reason a novel fast sequential pseudo inverse algorithm is also presented. Significantly improved results are obtained on both synthetic and clinical data.

  • 154.
    Kristenson, Margareta
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of health and environment. Östergötlands Läns Landsting, FHVC - Folkhälsovetenskapligt centrum, Förebygg.med.
    Lassvik, Claes
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Bergdahl, Björn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Kucinskiene, Z
    Aizieniene, L
    Ziedén, Bo
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Internal Medicine. Östergötlands Läns Landsting, MKC-2, GE: endomed.
    Schäfer Elinder, Liselott
    Olsson, Anders
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Internal Medicine. Östergötlands Läns Landsting, MKC-2, GE: endomed.
    Ultrasound determined carotid and femoral atherosclerosis in Lithuanian and Swedish men: The LiVicordia study2000In: Atherosclerosis, ISSN 0021-9150, E-ISSN 1879-1484, Vol. 151, no 2, p. 501-508Article in journal (Refereed)
    Abstract [en]

    Coronary heart disease mortality is four times higher in Lithuanian compared to Swedish middle-aged men. Using the same equipment (Acuson XP10 with 5 MHz linear transducer) and staff, we compared the amount of atherosclerosis in carotid and femoral arteries in 100 randomly sampled 50-year-old men in each of the cities Vilnius, Lithuania and Linköping, Sweden. Atherosclerotic plaques were more abundant in Vilnius men compared to Linköping men (53 versus 28% in the common carotid artery, 73 versus 37% in the common femoral artery, P<0.001 for both). Plaques were thicker and more extended in arteries of Vilnius men, and an ultrasound atherosclerosis score was higher in both carotid and femoral arteries (P<0.001 for all). More Vilnius men had a maximal intima-media thickness of the common femoral artery above 1 mm (P<0.005). Stiffness in the common carotid artery was higher in Vilnius men (P<0.001). In a linear regression model of the pooled material, after adjustment for city was made, smoking, systolic blood pressure, low density lipoprotein cholesterol and β-carotene (inversely) significantly contributed to a high total ultrasound score (r2=0.32). These findings show that the higher coronary mortality noted in Lithuanian men goes together with a higher prevalence of early peripheral atherosclerosis.

  • 155.
    Kukulski, T
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Hübbert, Laila
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Arnold, Martina
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Hatle, L
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Sutherland, George
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Normal regional right ventricular function and its change with age: a Doppler myocardial imaging study2000In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 13, p. 194-204Article in journal (Refereed)
  • 156.
    Kukulski, T
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Voigt, JU
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Wilkenshoff, Ursula
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Internal Medicine.
    Strotmann, JM
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Hatle, L
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Sutherland, GR
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    A comparison of regional myocardial velocity information derived by pulsed and color: an in vitro and in vivo stydy2000In: Echocardiography, ISSN 0742-2822, E-ISSN 1540-8175, Vol. 17, p. 639-951Article in journal (Refereed)
  • 157.
    Kvitting, John-Peder Escobar
    et al.
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery. Linköping University, Faculty of Health Sciences.
    Dyverfeldt, Petter
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Carlhäll, Carljohan
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Sigfridsson, Andreas
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Bolger, Ann F
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ebbers, Tino
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Engvall, Jan
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Magnetresonanstomografi ger unika möjligheter att bedöma blodflödet och dess inverkan på hjärt och kärlsystemet.2009In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 106, p. 1901-1904Article in journal (Other academic)
  • 158.
    Kvitting, J.P.
    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 Thoracic and Vascular Surgery.
    Sigfridsson, A.
    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.
    Wigström, L.
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences.
    Bolger, A.F.
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Karlsson, Matts
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics . Linköping University, The Institute of Technology.
    Analysis of human myocardial dynamics using virtual markers based on magnetic resonance imaging2010In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 30, no 1, p. 23-29Article in journal (Refereed)
    Abstract [en]

    Background: Myocardial dynamics are three-dimensional (3D) and time-varying. Cineradiography of surgically implanted makers in animals or patients is accurate for assessing these events, but this invasive method potentially alters myocardial motion. The aim of the study was to quantify myocardial motion using magnetic resonance imaging (MRI) and hence to provide a non-invasive approach to characterize 3D myocardial dynamics.

    Methods: Myocardial motion was quantified in ten normal volunteers by tracking the Lagrangian motion of individual points (i.e. virtual markers), based on time-resolved 3D phase-contrast MRI data and Fourier tracking. Nine points in the myocardium were tracked over the entire cardiac cycle, allowing a wire frame model to be generated and systolic and diastolic events identified.

    Results: Radius of curvature of the left ventricular (LV) wall was calculated from the virtual markers; the ratio between the anterior–posterior (AP) and septal–lateral (SL) walls in the LV shows an oval shape of the apical short axis plane at end systole (ES) and more circular at end diastole (ED). The AP/SL ratio for the basal plane shows an oval shape at ES and ED. We found that the rotation of the basal plane in ES was less compared to the apical plane [−2·0 ± 2·2 versus 4·1 ± 2·6 degrees (P<0·005)]. The apical plane rotated counter clock wise as viewed from the apex.

    Conclusion: This new non-invasive tool, despite current limitations in temporal and spatial resolution, may provide a comprehensive set of virtual myocardial markers throughout the entire LV without the confounding effects introduced by surgical implantation.

  • 159.
    Kühme, Tobias
    et al.
    Linköping University, Department of Medicine and Care. Linköping University, Faculty of Health Sciences.
    Säfström, Kåge
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Nielsen, Niels Erik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Olin, Christian
    Rupture of a synthetic VSD patch 28 years after total correction of Fallot's anomaly2006In: Annals of Thoracic Surgery, ISSN 0003-4975, E-ISSN 1552-6259, Vol. 81, no 4, p. 1510-1512Article in journal (Refereed)
    Abstract [en]

    Patients operated on for complex congenital heart malformations need continuous follow-up. We present a male patient born in 1948 with Fallot's anomaly. A total correction was performed when he was 21 years old. Twenty-eight years after the operation, at routine follow-up, he presented with a significant left-to-right shunt because of a new ventricular septal defect. During the operation we found the original patch to be fractured with a central perforation. The patient received a new patch and has been without any clinical symptoms since. © 2006 by The Society of Thoracic Surgeons.

  • 160.
    Kümhe, Tobias
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Franzén, Stefan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    The simple solution to a complex case2001In: Journal of Neurology, Neurosurgery and Psychiatry, ISSN 0022-3050, E-ISSN 1468-330X, Vol. 70, no 2, p. 263-Article in journal (Refereed)
  • 161.
    Landtblom, Anne-Marie
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Dige, N
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Schwerdt, K
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Säfström, Kåge
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL.
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    A case of Kleine-Levin syndrome examined with SPECT and neuropsychological testing2002In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 105, no 4, p. 318-321Article in journal (Refereed)
    Abstract [en]

    A case of Kleine-Levin syndrome with typical periodic hypersomnia and bulemia was diagnosed. On examination with single photo emission tomography (SPECT) (CERETEC«) during a relapse period and 2 weeks later there was marked cortical hypoperfusion of the frontal and temporal lobes, especially on the left side as well as in the right parietal lobe. Neuropsychological testing performed 1 week after a relapse showed a reduction in encoding to memory function of verbal learning indicating neocortical damage of the left fronto-temporal region. A follow-up 2 months later after the patient had spontaneously recovered showed only a slight left fronto-temporal disturbance. CT and MRI of the brain were normal although the MRI showed a large and asymmetric mamillary body. Neuropsychological testing 6 years after recovery showed pronounced reduction in short-time verbal and visual memory. Seven years after recovery SPECT demonstrated a normalized frontal perfusion but still a slight hypoperfusion in the left temporal lobe. Our results correlate to autopsy findings in two cases described previously.

  • 162.
    Landtblom, Anne-Marie
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Dige, N
    Schwerdt, K
    Säfström, Kåge
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radiology. Östergötlands Läns Landsting, Centre for Medical Imaging, Department of Radiology UHL.
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Short-term memory dysfunction in Kleine-Levin syndrome2003In: Acta Neurologica Scandinavica, ISSN 0001-6314, E-ISSN 1600-0404, Vol. 108, no 5, p. 363-367Article in journal (Refereed)
    Abstract [en]

    Background - A previous investigation at our department of a young man with typical Kleine-Levin syndrome revealed short-term memory dysfunction as well as hypoperfusion of the temporal lobes on single photon emission tomography (SPECT) (CERETECR) examination, 6 and 7 years after recovery, suggesting long lasting or even permanent cerebral dysfunction. Patients and methods - We investigated four cases with classical adolescent Kleine-Levin syndrome characterized by hypersomnia and typical associated symptoms. We used neuropsychological testing and SPECT (CERETECR) of the brain. The results from the previous report related to above is included. Results - Examination with SPECT (CERETECR) during remission revealed hypoperfusion of the temporal lobes and fronto-temporal region in two of four cases. There were normal findings in two. Neuropsychological testing performed during remission showed reduction in the short-term memory capacity in all four cases. Conclusion - It is striking that all the cases investigated showed short-term memory dysfunction. One patient who had recovered from paroxysmal symptoms (hypersomnia attacks and bulimia) 6 years earlier showed progress in the short-term memory dysfunction. A pathologic condition in the temporal lobes may be suspected in Kleine-Levin syndrome.

  • 163.
    Lassvik, Claes
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ultraljudsduplex värdefullt redskap i kärldiagnostik.2000In: Läkartidningen, ISSN 0023-7205, E-ISSN 1652-7518, Vol. 97, p. 4983-4990Article in journal (Other academic)
  • 164.
    Lindenberger, Marcus
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Kjellberg, Margareta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Karlsson, Erling
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Pericardiocentesis guided by 2-D echocardiography: The method of choice for treatment of pericardial effusion2003In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 253, no 4, p. 411-417Article in journal (Refereed)
    Abstract [en]

    Background. Percutaneous pericardiocentesis guided by 2-D echocardiography has been used at Link÷ping Heart Centre since 1983. Aim. To evaluate our experience of this method including a follow-up and also to determine the aetiology of pericardial effusion. Methods. A retrospective study including 120 of 252 consecutive patients punctured. Results. The two most common aetiologies were cardiac surgery (77% valve surgery), followed by malignant disease. The postsurgical effusions became clinically important a median of 12 days after surgery (range 0-56 days). The median survival in the group with malignant disease was 89 days (30-day survival 87%, 1-year survival 10%). Indwelling catheter was used in 93% of the patients. There was no mortality but one patient needed a second pericardiocentesis after an accidental puncture of the right ventricle. Nine patients had rhythm aberrations. Recurring effusion that needed puncture was seen in 8%. Conclusion. Pericardiocentesis guided by 2-D echocardiography is a safe and efficient method to treat pericardial effusion and also valuable as palliative treatment for patients with malignant aetiology of the effusion.

  • 165.
    Lindenberger, Marcus
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Vascular surgery.
    Olsen, H
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Increased susceptibility to acute hypovolemia in ageing females2004In: Svenska Läkaresällskapets Riksstämma,2004, 2004Conference paper (Other academic)
  • 166.
    Lindenberger, Marcus
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Vascular surgery.
    Olsen, H
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Indications of increased susceptibility to hypovolemic circulatory stress in ageing females2004In: 14th meeting of Hypertension,2004, 2004Conference paper (Other academic)
  • 167.
    Lindström, Lena
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Annular Motion: Assessment of Cardiac Function using Echocardiography and Magnetic Resonance Imaging2000Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis concentrates on the assessment of cardiac function, both systolic and diastolic using variables originating from the longitudinal motion of the heart using both established and novel non-invasive imaging techniques. We developed a new magnetic resonance imaging (MRI) technique that creates an M-mode MRI image, analogous to the one used in echocardiography and enables quantitative assessment of cardiac motion. The MRI M-mode method was compared with M-mode echocardiography in a phantom study, by measuring mitral and tricuspid annular motion in 20 normal subjects, and in a study of right ventricular function in 17 patients after coronary artery bypass surgery. The agreement between M-mode MRI and Mmode echocardiography was good. However, the amplitudes were somewhat higher measured by MRI, probably because of less angle error in the MRI calculation, furthermore the lower resolution in the MRI image may have contributed.

    Pulsed tissue Doppler, a recently developed Doppler modality that gives the possibility of recording instantaneous annular /or myocardial velocities on-line, was used to obtain reference values of mitral and tricuspid annular motion in 27 normal subjects of different ages. Diastolic left ventricular function was assessed in 15 patients with systemic hypertension and in 10 patients with moderate to severe aortic stenosis. Furthermore, pulsed tissue Doppler was used in the evaluation of right and left ventricular function in 15 patients with arrhythmogenic right ventricular cardiomyopathy (ARVC).

    The mitral and tricuspid annular velocity pattern in normal subjects is characterised by three major components: asystolic (SA) velocity, an early (EA) diastolic velocity, and a late (AA) diastolic velocity. In normal young subjects, the EA-peak velocity was highest; with increasing age, the EA-peak velocity decreases and the AA-peak velocity increases, with similar changes in both the mitral and tricuspid annular velocity pattern. In patients with left ventricular hypertrophy the EA/AA-ratio was significantly decreased compared with age- match normal subjects. Comparing ARVC patients with normal subjects the tricuspid annular EA-peak velocity was significantly decreased as well as the lateral SA-peak velocity. Our result indicates that abnormal diastolic tricuspid annular velocity pattern may be an early sign of right ventricular myocardial dysfunction in patients with ARVC. The septal mitral annular SA-peak velocity was significantly decreased in ARVC patients compared to the controls. This in accordance with subjective analysis of echocardiographic wall motion and T1-201 SPECT that showed left ventricular abnormalities in 93% of the patients predominantly located in the anteroseptal and posteroseptal segments.

    List of papers
    1. M-mode magnetic resonance imaging: a new modality for assessing cardiac function
    Open this publication in new window or tab >>M-mode magnetic resonance imaging: a new modality for assessing cardiac function
    Show others...
    1995 (English)In: Clinical Physiology, ISSN 0144-5979, E-ISSN 1365-2281, Vol. 15, no 4, p. 397-407Article in journal (Refereed) Published
    Abstract [en]

    Magnetic resonance imaging (MRI) studies of the heart have been used for some years, but there are few tools available to quantify cardiac motion. A method has been developed that creates an M-mode MRI image, analogous to the one used in echocardiography, to display motion along a line as a function of time. The M-mode image is created from MRI images acquired with an ordinary gradient echo cine sequence. In a cinematographic display of the images, a cursor line can be positioned in order to determine the orientation of the measurement. A resampling algorithm then calculates the appearance of the M-mode image along the cursor line. The MRI method has been compared to echocardiographic M-mode in a phantom study and by measuring mitral and tricuspid annulus motion in 20 normal subjects. The phantom study showed no significant differences between MRI and echocardiographic M-mode measurements (difference mm). The annulus motion exhibits a similar pattern using both methods and the measured amplitudes are in close agreement. M-mode MRI provides similar information to echocardiography, but the cursor line can be placed arbitrarily within the image plane and the method is thus not limited to certain acoustic windows. This makes M-mode MRI a promising technique for assessing cardiac motion.

    Keywords
    cardiac motion, heart, image processing, MRI, M-mode
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-79469 (URN)10.1111/j.1475-097X.1995.tb00529.x (DOI)
    Available from: 2012-08-02 Created: 2012-08-02 Last updated: 2017-12-07Bibliographically approved
    2. Pulsed tissue Doppler evaluation of mitral annulus motion: A new window to assessment of diastolic function
    Open this publication in new window or tab >>Pulsed tissue Doppler evaluation of mitral annulus motion: A new window to assessment of diastolic function
    1999 (English)In: Clinical Physiology, ISSN 0144-5979, E-ISSN 1365-2281, Vol. 19, no 1, p. 1-10Article in journal (Refereed) Published
    Abstract [en]

    Diastolic dysfunction is an important cause of cardiac heart failure. To date detailed assessment of diastolic left ventricular (LV) function has required invasive methods which are impractical in the clinical routine. The prevailing non-invasive method has been Doppler echocardiography with use of mitral inflow and pulmonary vein inflow parameters, measurements providing no direct assessment of either ventricular relaxation or compliance, and influenced by multiple haemodynamic factors. We sought to determine the tissue Doppler pattern from the mitral annulus motion in normals and in patients with expected LV-diastolic dysfunction. Using pulsed tissue Doppler we recorded peak velocities from the mitral annulus motion in 16 young normals, 10 older normals and in two groups of patients expected to have an LV-diastolic relaxation abnormality, i.e. 15 patients with systemic hypertension and 10 patients with significant aortic stenosis. The peak early diastolic (E) annulus velocity was significantly (< 0·001) lower in older normals compared with young, and the late diastolic velocity (A) was higher (< 0·01). Compared with the older normals, patients showed significantly lower E-velocities (< 0·05 hypertensive patients), more pronounced in the patients with aortic stenosis (< 0·001), but the A-velocities were not higher. In systole a decrease in peak velocity was noted with increasing age and in patients with aortic stenosis. In conclusion, pulsed tissue Doppler measurement of annulus motion seems to provide valuable and easily obtainable information about LV-diastolic function, and furthermore there is a striking change in velocity pattern with increasing age which necessitates age-matched reference values.

    Keywords
    diastolic function, echocardiography, tissue Doppler
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26987 (URN)10.1046/j.1365-2281.1999.00137.x (DOI)11623 (Local ID)11623 (Archive number)11623 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    3. Lack of effect of synthetic pericardial substitute on right ventricular function after coronary artery bypass surgery: An echocardiographic and magnetic resonance imaging study
    Open this publication in new window or tab >>Lack of effect of synthetic pericardial substitute on right ventricular function after coronary artery bypass surgery: An echocardiographic and magnetic resonance imaging study
    Show others...
    2000 (English)In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 34, no 3, p. 331-338Article in journal (Refereed) Published
    Abstract [en]

    Abnormal right heart function after cardiac surgery is a well-known finding. Inadequate preservation during the operation and restricted cardiac motion due to pericardial adhesions have been proposed as underlying mechanisms. This study focuses on the impact of a pericardial substitute implantation on right ventricular function, using echocardiography and magnetic resonance imaging. A test group of six patients (mean age 54 years) was examined before surgery, and 4-15 days and 5-9 months after coronary artery bypass surgery, where the pericardium was closed with a biodegradable pericardial patch. A group of 11 patients (mean age 63 years) in whom the pericardium was left open served as controls. Tricuspid annulus motion was markedly decreased, abnormal septal motion was present and decreased systolic to diastolic ratio in the vena cava superior flow was present in all patients in both groups one week after surgery. At the late follow-up, all patients still had decreased tricuspid annulus motion, while 17% of the patients in the test group and 22% of the patients in the control group (ns) demonstrated normal septal motion. We conclude that closing the pericardium with a biodegradable patch does not affect the postoperative changes in right heart function normally seen after open-heart surgery.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26784 (URN)10935782 (PubMedID)11389 (Local ID)11389 (Archive number)11389 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    4. Echocardiographic assessment of arrhythmogenic right ventricular cardiomyopathy
    Open this publication in new window or tab >>Echocardiographic assessment of arrhythmogenic right ventricular cardiomyopathy
    2001 (English)In: Heart, ISSN 1355-6037, E-ISSN 1468-201X, Vol. 86, no 1, p. 31-38Article in journal (Refereed) Published
    Abstract [en]

    OBJECTIVE To evaluate new echocardiographic modes in the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC).

    DESIGN Prospective observational study.

    SETTING University Hospital.

    SUBJECTS 15 patients with ARVC and a control group of 25 healthy subjects.

    METHODS Transthoracic echocardiography included cross sectional measurements of the right ventricular outflow tract, right ventricular inflow tract, and right ventricular body. Wall motion was analysed subjectively. M mode and pulsed tissue Doppler techniques were used for quantitative measurement of tricuspid annular motion at the lateral, septal, posterior, and anterior positions. Doppler assessment of tricuspid flow and systemic venous flow was also performed.

    RESULTS Assessed by M mode, the total amplitude of the tricuspid annular motion was significantly decreased in the lateral, septal, and posterior positions in the patients compared with the controls. The tissue Doppler velocity pattern showed decreased early diastolic peak annular (EA) velocity and an accompanying decrease in early (EA) to late diastolic (AA) velocity ratio in all positions; the systolic annular velocity was significantly decreased only in the lateral position. Four patients had normal right ventricular dimensions and three were judged to have normal right ventricular wall motion. The patient group had also a significantly decreased tricuspid flow E:A ratio.

    CONCLUSIONS Tricuspid annular measurements are valuable, easy to obtain, and allow quantitative assessment of right ventricular function. ARVC patients showed an abnormal velocity pattern that may be an early but non-specific sign of the disease. Normal right ventricular dimensions do not exclude ARVC, and subjective detection of early changes in wall motion may be difficult.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26984 (URN)10.1136/heart.86.1.31 (DOI)11620 (Local ID)11620 (Archive number)11620 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    5. Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy: A scintigraphic and echocardiographic study
    Open this publication in new window or tab >>Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy: A scintigraphic and echocardiographic study
    2005 (English)In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 25, no 3, p. 171-177Article in journal (Refereed) Published
    Abstract [en]

    Background:  Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy (ARVC) is a common finding in autopsy studies. In clinical studies using myocardial scintigraphy, MRI and echocardiography, contradictory results have been reported. In this study, we therefore investigated a group of 15 patients with ARVC using thallium-201 (Tl) single-photon emission tomography (SPECT) and echocardiography including assessment of mitral annular motion with M-mode and pulsed tissue Doppler.

    Methods:  Exercise and rest Tl-201 SPECT were performed in 15 patients with ARVC. The time from diagnosis of the disease varied from less than 1–16 years. All patients fulfilled the established diagnostic criteria for ARVC. An echocardiographic examination, including assessment of left and right ventricular motion and measurements of the mitral annulus motion with M-mode and pulsed tissue Doppler was performed in the patients and in 25 normal subjects.

    Results:  Tl-201 uptake defects in the left ventricular myocardium were present in all except one patient (93%). The uptake defects were predominantly located to the anteroseptal and basal posterior segments. Wall motion abnormalities were seen in the same segments, and in addition to this, in the septal area. In line with this, the total amplitude and the peak systolic velocity of mitral annular motion at the septal point were significantly decreased in the patients compared with the control group.

    Conclusions:  Our data show that left ventricular involvement is common in ARVC. Tl-201 SPECT and echocardiographic abnormalities were seen not only in patients with long-lasting symptoms but also in asymptomatic patients and in those with short duration of symptoms.

    Keywords
    annular motion, pulsed tissue Doppler, T1-201 scintigraphy, wall motion abnormalities
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-28426 (URN)10.1111/j.1475-097X.2005.00607.x (DOI)13565 (Local ID)13565 (Archive number)13565 (OAI)
    Available from: 2009-10-09 Created: 2009-10-09 Last updated: 2017-12-13Bibliographically approved
  • 168.
    Lindström, Lena
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Höger kammares ekokardiografiska anatomi och funktion (den bortglömda kammaren Hur och varför skall högerkammarfunktionen bedömas?)2007In: IX Svenska Kardiovaskulära vårmötet,2007, 2007Conference paper (Other academic)
  • 169.
    Lindström, Lena
    et al.
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Nylander, Eva
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Larsson, Hans
    Linköping University, Department of Medicine and Care, Cardiology. Linköping University, Faculty of Health Sciences.
    Wranne, Bengt
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy: A scintigraphic and echocardiographic study2005In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 25, no 3, p. 171-177Article in journal (Refereed)
    Abstract [en]

    Background:  Left ventricular involvement in arrhythmogenic right ventricular cardiomyopathy (ARVC) is a common finding in autopsy studies. In clinical studies using myocardial scintigraphy, MRI and echocardiography, contradictory results have been reported. In this study, we therefore investigated a group of 15 patients with ARVC using thallium-201 (Tl) single-photon emission tomography (SPECT) and echocardiography including assessment of mitral annular motion with M-mode and pulsed tissue Doppler.

    Methods:  Exercise and rest Tl-201 SPECT were performed in 15 patients with ARVC. The time from diagnosis of the disease varied from less than 1–16 years. All patients fulfilled the established diagnostic criteria for ARVC. An echocardiographic examination, including assessment of left and right ventricular motion and measurements of the mitral annulus motion with M-mode and pulsed tissue Doppler was performed in the patients and in 25 normal subjects.

    Results:  Tl-201 uptake defects in the left ventricular myocardium were present in all except one patient (93%). The uptake defects were predominantly located to the anteroseptal and basal posterior segments. Wall motion abnormalities were seen in the same segments, and in addition to this, in the septal area. In line with this, the total amplitude and the peak systolic velocity of mitral annular motion at the septal point were significantly decreased in the patients compared with the control group.

    Conclusions:  Our data show that left ventricular involvement is common in ARVC. Tl-201 SPECT and echocardiographic abnormalities were seen not only in patients with long-lasting symptoms but also in asymptomatic patients and in those with short duration of symptoms.

  • 170.
    Lindström, Lena
    et al.
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Wigström, Lars
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Dahlin, Lars-Göran
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Aren, Claes
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Wranne, Bengt
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Lack of effect of synthetic pericardial substitute on right ventricular function after coronary artery bypass surgery: An echocardiographic and magnetic resonance imaging study2000In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 34, no 3, p. 331-338Article in journal (Refereed)
    Abstract [en]

    Abnormal right heart function after cardiac surgery is a well-known finding. Inadequate preservation during the operation and restricted cardiac motion due to pericardial adhesions have been proposed as underlying mechanisms. This study focuses on the impact of a pericardial substitute implantation on right ventricular function, using echocardiography and magnetic resonance imaging. A test group of six patients (mean age 54 years) was examined before surgery, and 4-15 days and 5-9 months after coronary artery bypass surgery, where the pericardium was closed with a biodegradable pericardial patch. A group of 11 patients (mean age 63 years) in whom the pericardium was left open served as controls. Tricuspid annulus motion was markedly decreased, abnormal septal motion was present and decreased systolic to diastolic ratio in the vena cava superior flow was present in all patients in both groups one week after surgery. At the late follow-up, all patients still had decreased tricuspid annulus motion, while 17% of the patients in the test group and 22% of the patients in the control group (ns) demonstrated normal septal motion. We conclude that closing the pericardium with a biodegradable patch does not affect the postoperative changes in right heart function normally seen after open-heart surgery.

  • 171.
    Lindström, Lena
    et al.
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Wilkenshoff, U.
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Larsson, H.
    Linköping University, Department of Medicine and Care, Cardiology. Linköping University, Faculty of Health Sciences.
    Wranne, Bengt
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Echocardiographic assessment of arrhythmogenic right ventricular cardiomyopathy2001In: Heart, ISSN 1355-6037, E-ISSN 1468-201X, Vol. 86, no 1, p. 31-38Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE To evaluate new echocardiographic modes in the diagnosis of arrhythmogenic right ventricular cardiomyopathy (ARVC).

    DESIGN Prospective observational study.

    SETTING University Hospital.

    SUBJECTS 15 patients with ARVC and a control group of 25 healthy subjects.

    METHODS Transthoracic echocardiography included cross sectional measurements of the right ventricular outflow tract, right ventricular inflow tract, and right ventricular body. Wall motion was analysed subjectively. M mode and pulsed tissue Doppler techniques were used for quantitative measurement of tricuspid annular motion at the lateral, septal, posterior, and anterior positions. Doppler assessment of tricuspid flow and systemic venous flow was also performed.

    RESULTS Assessed by M mode, the total amplitude of the tricuspid annular motion was significantly decreased in the lateral, septal, and posterior positions in the patients compared with the controls. The tissue Doppler velocity pattern showed decreased early diastolic peak annular (EA) velocity and an accompanying decrease in early (EA) to late diastolic (AA) velocity ratio in all positions; the systolic annular velocity was significantly decreased only in the lateral position. Four patients had normal right ventricular dimensions and three were judged to have normal right ventricular wall motion. The patient group had also a significantly decreased tricuspid flow E:A ratio.

    CONCLUSIONS Tricuspid annular measurements are valuable, easy to obtain, and allow quantitative assessment of right ventricular function. ARVC patients showed an abnormal velocity pattern that may be an early but non-specific sign of the disease. Normal right ventricular dimensions do not exclude ARVC, and subjective detection of early changes in wall motion may be difficult.

  • 172.
    Lindström, Lena
    et al.
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Wranne, Bengt
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Pulsed tissue Doppler evaluation of mitral annulus motion: A new window to assessment of diastolic function1999In: Clinical Physiology, ISSN 0144-5979, E-ISSN 1365-2281, Vol. 19, no 1, p. 1-10Article in journal (Refereed)
    Abstract [en]

    Diastolic dysfunction is an important cause of cardiac heart failure. To date detailed assessment of diastolic left ventricular (LV) function has required invasive methods which are impractical in the clinical routine. The prevailing non-invasive method has been Doppler echocardiography with use of mitral inflow and pulmonary vein inflow parameters, measurements providing no direct assessment of either ventricular relaxation or compliance, and influenced by multiple haemodynamic factors. We sought to determine the tissue Doppler pattern from the mitral annulus motion in normals and in patients with expected LV-diastolic dysfunction. Using pulsed tissue Doppler we recorded peak velocities from the mitral annulus motion in 16 young normals, 10 older normals and in two groups of patients expected to have an LV-diastolic relaxation abnormality, i.e. 15 patients with systemic hypertension and 10 patients with significant aortic stenosis. The peak early diastolic (E) annulus velocity was significantly (< 0·001) lower in older normals compared with young, and the late diastolic velocity (A) was higher (< 0·01). Compared with the older normals, patients showed significantly lower E-velocities (< 0·05 hypertensive patients), more pronounced in the patients with aortic stenosis (< 0·001), but the A-velocities were not higher. In systole a decrease in peak velocity was noted with increasing age and in patients with aortic stenosis. In conclusion, pulsed tissue Doppler measurement of annulus motion seems to provide valuable and easily obtainable information about LV-diastolic function, and furthermore there is a striking change in velocity pattern with increasing age which necessitates age-matched reference values.

  • 173.
    Ljungman, Anders
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Occupational and Environmental Medicine .
    Silén, Charlotte
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Examination involving students as peer examiners2008In: Assessment & Evaluation in Higher Education, ISSN 0260-2938, E-ISSN 1469-297X, Vol. 33, no 3, p. 289-300Article in journal (Refereed)
    Abstract [en]

    The main interest in this article is students' involvement in assessment as a part of growth towards self-directedness in learning. In order to enhance students' development of autonomy in learning, a project involving 'older' students as peer examiners for 'younger' students was designed and carried out. Students in the sixth semester in a PBL-based Master's program of Medical Biology participated, together with faculty, as examiners of fifth-semester students. The examination and the assessment situation was carefully designed based on learning theories, empirical evidence and experiences underpinning student-centred learning, especially in the form of PBL used at the faculty. The project was evaluated and analysed in order to understand students' learning processes related to the responsibility for assessing peers. The situation of the peer examiners was interpreted based on their own experiences with statements from the students assessed and faculty involved in the assessment. Evaluations from six occasions, spring and fall, 2003-2005, were included in the study. The findings suggest that involving students in assessment as equal partners with faculty makes it is possible for students to apprehend the metacognitive competences needed to be responsible and autonomous in learning. The peer examiners experience motivation to learn about learning, they acquire tacit knowledge about assessment and they learn through being involved and trusted. The student-centred educational context, which requires responsibility throughout the programme, is recognized as very important.   

  • 174.
    Loyd, Dan
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Wranne, Bengt
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Doppler prediction of transvalvular gradient and stenotic orifice area.1988In: American Journal of Cardiology, ISSN 0002-9149, E-ISSN 1879-1913, Vol. 61, no 11, p. 958-959Article in journal (Refereed)
  • 175.
    Loyd, Dan
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Wranne, Bengt
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    MITRAL PRESSURE HALF-TIME TECHNIQUE FOR ASSESSING SEVERITY OF MITRAL-STENOSIS - ESSENTIAL PARAMETERS1989In: IMAGES OF THE TWENTY-FIRST CENTURY, PTS 1-6, 1989, Vol. 11Conference paper (Refereed)
    Abstract [en]

    The flow through a stenotic mitral valve, which is mainly determined by the cross-sectional area of the valve and the pressure difference across it, is discussed. The gradient half-time is an attempt to describe the area from the decline in transmitral pressure difference alone. The gradient half-time increases with increasing severity of the stenosis. Besides the area of the mitral valve, there are other factors influencing the gradient half-time. Such factors are the transported volume and the initial pressure gradient. The compliance of the cardiac chambers and the pulmonary venous flow also influence the gradient half-time, but through changes in the pressure difference across the valve. The problem can therefore be analyzed either with or without inclusion of compliance in the calculations

  • 176.
    Loyd, Dan
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Wranne, Bengt
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Pressure half-time does not always predict mitral valve area correctly.1988In: Journal of the American Society of Echocardiography, ISSN 0894-7317, E-ISSN 1097-6795, Vol. 1, no 5, p. 313-321Article in journal (Refereed)
    Abstract [en]

    A theory is presented elucidating factors that influence the pressure half-time. By combining the Bernoulli and continuity equations and making certain assumptions about the shape of the atrioventricular pressure difference decay, it can be shown that valve area, volume transported across that area, and initial pressure difference influence the pressure half-time according to a formula in which the pressure half-time is related to V/(Ao square root of delta po), where V is the transported volume across the orifice with the area Ao, and delta po is the initial pressure difference across that area. In a subsequent hydraulic model experiment pressure half-time was determined for three different hole areas, with various initial volumes and initial pressure gradients. We did not obtain a unique relation between the pressure half-time and area. Instead the results supported our theory, and we found a close linear relationship between area and V/(T0.5 square root of delta po) (correlation coefficient [r] = 0.998), as predicted in the theory (T0.5 = pressure half-time). Clinical examples in which the pressure half-time may be misleading in the assessment of severity of mitral stenosis are presented.

  • 177.
    Loyd, Dan
    et al.
    Linköping University, Department of Management and Engineering, Applied Thermodynamics and Fluid Mechanics. Linköping University, The Institute of Technology.
    BARCLAY, SA
    XIONG, Changsheng
    ANDERSSON, Gunnar
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Wranne, Bengt
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    ECHOCARDIOGRAPHIC ASSESSMENT OF HEART-VALVE REGURGITANT FLOW USING THE FLOW CONVERGENCE METHOD1991In: PROCEEDINGS OF THE ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY, VOL 13, PTS 1-5, 1991, p. 191-192Conference paper (Refereed)
  • 178.
    Lund, Eva
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radio Physics.
    Kendall, Sally
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Neuroscience and Locomotion, Rehabilitation Medicine. Östergötlands Läns Landsting, Centre for Medicine, Pain and Rehabilitation Centre.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Bengtsson, Ann
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Rheumatology. Östergötlands Läns Landsting, Centre for Medicine, Department of Rheumatology in Östergötland.
    Muscle metabolism in fibromyalgia studied by P-31 magnetic resonance spectroscopy during aerobic and anaerobic exercise2003In: Scandinavian Journal of Rheumatology, ISSN 0300-9742, E-ISSN 1502-7732, Vol. 32, no 3, p. 138-145Article in journal (Refereed)
    Abstract [en]

    Objective: To investigate mechanisms underlying the reduced work capacity of fibromyalgia (FM) patients were compared to healthy controls at specified workloads, using P-31 magnetic resonance spectroscopy (MRS). Methods: The forearm flexor muscle group was examined with MRS at rest, at sub maximal and at maximal controlled dynamic work as well as at maximal isometric contraction. Aerobic fitness was determined by bicycle ergonometry. Results: Metabolite concentrations and muscle pH were similar for patients and controls at lower workloads. At maximal dynamic and static contractions the concentration of inorganic phosphate was lower and at static contractions the pH decrease was smaller in patients. The performed work by patients was only 50% compared to controls and the patients experienced more pain. Maximal oxygen uptake was lower in the fibromyalgia group. Expired gas-analysis in this group showed ventilatory equivalents at similar relative levels of maximal work capacity. Conclusion: Fibromyalgia patients seem to utilise less of the energy rich phosphorous metabolites at maximal work despite pH reduction. They seemed to be less aerobic fitted and reached the anaerobic threshold earlier than the controls.

  • 179.
    Löf, Marie
    et al.
    Linköping University, Department of Biomedicine and Surgery, Nutrition. Linköping University, Faculty of Health Sciences.
    Olausson, Hanna
    Linköping University, Department of Biomedicine and Surgery, Nutrition. Linköping University, Faculty of Health Sciences.
    Boström, Karin
    Lust och Hälsa (Pleasure and Health) Clinic, Linköping, Sweden.
    Janerot-Sjöberg, Birgitta
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Sohlström, Annica
    Linköping University, Department of Biomedicine and Surgery, Nutrition. Linköping University, Faculty of Health Sciences.
    Forsum, Elisabet
    Linköping University, Department of Biomedicine and Surgery, Nutrition. Linköping University, Faculty of Health Sciences.
    Changes in basal metabolic rate during pregnancy in relation to changes in body weight and composition, cardiac output, insulin-like growth factor I, and thyroid hormones and in relation to fetal growth2005In: American Journal of Clinical Nutrition, ISSN 0002-9165, E-ISSN 1938-3207, Vol. 81, no 3, p. 678-685Article in journal (Refereed)
    Abstract [en]

    Background: The total energy cost of pregnancy is largely due to an elevated basal metabolic rate (BMR). Large variations in the BMR response to pregnancy have been reported, but the factors associated with this variability are incompletely known.

    Objective: The objective was to identify factors associated with variability in the BMR response to pregnancy.

    Design: In 22 healthy women, BMR, body weight (BW), total body fat (TBF), fat-free mass (FFM), circulatory variables, serum concentrations of insulin-like growth factor I (IGF-I), and thyroid hormones were measured before pregnancy and in gestational weeks 14 and 32. BMR and BW were also measured in gestational weeks 8, 20, and 35. Fetal weight was estimated in gestational week 31.

    Results: In gestational week 14, the increase in BMR correlated significantly with the corresponding increase in BW and with the prepregnancy percentage of TBF. Together these variables explained ≈40% of the variability in the BMR response. In gestational week 32, the increase in BMR correlated significantly with the corresponding changes in BW, TBF, FFM, IGF-I, cardiac output, and free triiodothyronine. The increase in BW in combination with fetal weight or with the elevated concentration of IGF-I in serum explained ≈60% of the variability in the increase in BMR.

    Conclusions: Weight gain and the prepregnancy percentage of TBF—ie, factors related to the maternal nutritional situation—are important factors with regard to the variability in the BMR response to pregnancy. Thus, it is important to consider the nutritional situation before and during gestation when assessing pregnancy energy requirements.

  • 180.
    Lönn, Urban
    et al.
    Thoraxklin Universitetssjukhuset, Linköping.
    Wulff, J
    Keck, K-Y
    Wranne, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, 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.
    Peterzén, Bengt
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Intensive Care UHL.
    Ahn, Henrik Casimir
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Flow characteristics of the hemopump: An experimental in Vitro study1997In: Annals of Thoracic Surgery, ISSN 0003-4975, E-ISSN 1552-6259, Vol. 63, no 1, p. 162-166Article in journal (Refereed)
  • 181.
    Malmgren, Maine
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Hellerström, Sabine
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ekberg, Stefan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radio Physics. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
    Gustafsson, A
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radio Physics. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
    Practical aspects on patient handling in 18F.FDG studies with dual-head coincidence gamma camera.2000In: Congress of the European Association of Nuclear Medicine, Paris 2000.,2000, 2000Conference paper (Refereed)
  • 182. Malmström, M
    et al.
    Ahlner, Johan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Carlsson, C
    Schmekel, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    No effect of chinese acupuncture on isocapnic hyperventilation with cold air in asthmatics, measured with impulse oscillometry.2002In: Acupuncture in Medicine, ISSN 0964-5284, Vol. 20, p. 66-73Article in journal (Refereed)
  • 183. Mustafa, S
    et al.
    Thulesius, Olav
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology.
    Hyperthermia-induced vasoconstriction of the carotid artery and the role of potassium channels2005In: Journal of Stroke & Cerebrovascular Diseases, ISSN 1052-3057, E-ISSN 1532-8511, Vol. 14, no 3, p. 122-126Article in journal (Refereed)
    Abstract [en]

    Clinical experience and experimental studies have shown that hyperthermia can cause cerebral ischaemia and brain damage. By in vitro experiments with heating, we previously were able to induce carotid artery constriction. The objective of the present study was to clarify the mechanism of this thermal response. Isometric tension was recorded in rabbit carotid artery specimens using organ baths during stepwise temperature elevation. The heating responses were investigated at basal tone, in precontracted vessels, after blocking of adrenergic responses and administration of potassium (K)-channel activators and inhibitors. Stepwise heating of carotid artery strips from 37°C to 47°C induced reproducible graded contraction. The hyperthermic responses were not due to adrenergic stimulation, which were reduced and resistant to neurogenic blockade by tetrodotoxin. Heating-induced contractions were potentiated by the K-channel inhibitors tetraethylammonium, BaCl2, charybdotoxin, and the Na+/K+ ATPase inhibitor ouabain. Levcromakalim (BRL), a K+-channel activator, reduced heating induced contractions. Heating of carotid artery preparations induced reversible graded vasoconstriction proportional to temperature. The heating-induced contractions were not mediated by an adrenergenic process, but rather were due to inhibition of K+ channels, which increases Ca2+ entry. In vivo, this reaction may lead to a disturbance of autoregulation of cerebral blood flow and ischemia with brain damage. © 2005 by National Stroke Association.

  • 184.
    Mølgaard, Jørgen
    Linköping University, Department of Medicine and Care, Internal Medicine. Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Intermittent Claudication: Prevalence and metabolic risk factors1997Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The prevalence of intermittent claudication (IC) in middle-aged men (45-69 years old) and metabolic risk factors for this disease was studied in a Swedish community. All 15 253 middle-aged male residents in Linköping community, were screened for symptoms of IC using a postal questionnaire, which included detailed questions about smoking habits and presence of hypertension and diabetes mellitus.

    The overall response rate was 86.6% (n=l3 209). The prevalence of walking-related pain was 9.3% (n=l232), and 4.2%(n=552) had symptoms consistent with peripheral atherosclerotic disease (PAD). All men with leg symptoms according to the classical Rose criteria for IC (1.2%, n=156), and a sample of subjects (0.6%, n=84) with symptoms indicating PAD, but not fully complying with the Rose c.riteria, were invited for further examination.

    Subjects with IC were compared with randomly selected sex- and age-matched controls from the same population. One control group was matched for smoking habits (n=157), and one control group consisted of never-smokers (n=143). Both claudicants and healthy controls underwent objective examination of the peripheral circulation with segmental blood pressure measurements and a short treadmill exercise test.

    IC could objectively be verified in 1.7% (n=219) of all middle-aged men. The prevalence of IC was highly age-dependent and objectively verified IC increased from 0.2% in males 45-49 years old to 3.4% in those 65-69 years old. The prevalence of Rose IC was 0.5% for 45-49 year-old males and 2.0% for 65-69 year-old males. Thus the Rose criteria underestimated the prevalence ofiC in the older age group and overestimated it in the youngest age group. The estimated true average prevalence ofiC was at least 2.8%.

    More than half (57%) of all claudicants had ischaemic heart disease, and 21% had experienced a TIA or stroke.

    The metabolic studies investigated the role of dyslipidaemia and various metabolic abnormalities as risk factors for IC. Claudicants had multiple minor and moderate lipid and lipoprotein abnormalities, the strongest association being with elevated plasma levels of low-density lipoproteins (LDL) cholesterol and low levels of high-density lipoproteins (HDL) cholesterol, after multivariate adjustment for other major risk factors, i.e. hypertension, diabetes mellitus and smoking, and other factors that influence lipid levels. Ve1y-low-density lipoproteins (VLDL) triglycerides had a high univariate association, but did not contribute to risk for IC after multivariate adjustment for the above factors.

    Plasma lipoprotein (a) [Lp(a)] showed a strong association with risk for IC, which in part could be explained by a significant overrepresentation of small apo(a) isoforms, genetically associated with higher Lp(a) concentrations.

    Plasma a- and ~-carotene, Iycopene and retinol, but not a- or y-tocophcrol (vitamin E), showed a multivariate significant association with risk for IC in men. However, when dietary data had been accounted for, only the significance of plasma retinol remained. Lower plasma levels of lipid-soluble antioxidants after adjustment for lipid concentrations may be secondary to the atherosclerotic disease. Moderately elevated levels of plasma homocyst(e)ine, a su\fbydryl-containing amino acid with a known atherogenic potential, were significantly associated with risk of IC after adjustment for other risk factors in multivariate analyses.

    In conclusion, the risk for IC amongst middle-aged males was significantly associated with presence of both major traditional risk factors such as smoking (96%), hypertension (49%), diabetes mellitus (18%) and additional metabol~c risk factors such as dyslipidaemia, hypcrhomocyst(e)inaemia and elevated Lp(a) levels. Plasma levels of tocophero!s (vitamin E) were not associated with risk for IC. Carotenoids do not seem to contribute, whereas the role of plasma retinol remains unclear.

  • 185.
    Naidu Sjöswärd, Kerstin
    Linköping University, Department of Medicine and Care, Anaesthesiology. Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    A study on pharmacokinetic and pharmacodynamic effects of salbutamol-isomers2003Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Asthma is a common chronic inflammatory airway disease with reported increasing incidence over the world. Definition of asthma includes variable obstruction of the airways and increase in bronchial responsiveness to various stimuli. Drug treatment for asthma traditionally consists of bronchodilatory beta-receptor-agonists, often in combination with anti-inflammatory remedies such as corticosteroids.

    Salbutamol, a beta-receptor-agonist, has two stereo-isomers, R-salbutamol and Ssalbutamol, and is mostly given as a racemate. The ability for bronchodilation rests in the R-isomer, whereas the S-isomer has been suspected to increase bronchial hyperresponsiveness. Salbutamol m1dergoes stereo-selective metabolism favouring the Renantiomer. This leaves the S-enantiomer to rest for longer time in the body, and gives SiR-ratios in plasma exceeding one.

    Pharmacokinetic stndies were performed in twenty-two healthy volunteers. Stereoselective metabolism was more pronounced after oral delivery than after inhalation or endotracheal deposition of the racemate. Repeated inhalations gave rise to increasing SiR-ratios in plasma. Higher plasma-levels of both isomers were obtained in non-cortisone-treated patients with asthma compared to healthy volunteers after ingestion of racemic salbutamol. Following cortisone-treatment (budesonide) for one week the plasma-levels of asthmatic patients were lowered and resembled those of non-treated volunteers.

    Fifteen patients with asthma were randomly assigned to three repeated inhalations of racemic salbutamol over six hours or to "'non-treatment" in a crossover fashion. Twelve out of fomteen patients were still bronchodilated and also protected against the impact of a hyperventilation challenge four hours after inhalations. Two patients showed signs of increased response to provocation in spite of dilatation, compared to a non-treatment day. Plasma-levels of isomers did not explain these differences in response. Twenty-four patients with asthma were randomly assigned to one week's inhalation medication with either racemate or pure R-salbutamol in another crossover study. Six hours after the last inhaled dose, bronchodilation had faded away in all patients. R-salbutamol did not prove superior to racemate in protecting against a hyperventilation-challenge - on the contrary the most intensive hyper-responsiveness was seen after medication with the R-enantiomer. Plasma-levels drawn after medication with the pme R-isomer held considerable amounts of the S-isomer and tended to hold lower levels of the R-isomer than when equal amounts or R-salbutamol was given as racemate. A connection could be traced between this and increased hyper-responsiveness.

    Conclusion: Considerable inter-individual variations in stereoselective metabolism of salbutamol and in pharmacodynamic consequences of medication were found. These studies point at the necessity for further investigations.

    List of papers
    1. Stereoselective pharmacokinetics of S-salbutamol after administration of the racemate in healthy volunteers
    Open this publication in new window or tab >>Stereoselective pharmacokinetics of S-salbutamol after administration of the racemate in healthy volunteers
    Show others...
    1999 (English)In: European Respiratory Journal, ISSN 0903-1936, E-ISSN 1399-3003, Vol. 13, no 6, p. 1230-1235Article in journal (Refereed) Published
    Abstract [en]

    Racemic R,S-salbutamol is taken to relieve bronchial constriction. Only the R-enantiomer has bronchodilating properties. The S-enantiomer has been proposed to cause in vitro bronchial hyperreactivity in guinea-pigs. Stereoselective elimination of salbutamol has been shown, with S-salbutamol being eliminated at a slower rate than R-salbutamol. This study questioned whether rates of stereoselective elimination were similar after oral or lung delivery, and whether the S:R ratio would increase after repeated inhalations in a situation resembling a common clinical use. Eighteen healthy volunteers received single-dose racemic salbutamol as a solution instilled in the trachea during anaesthesia, as inhaled micronized powder and/or as ingested tablets. Five volunteers inhaled repeated doses of racemic salbutamol. Concentrations in plasma and urine were measured using a technique which allowed chiral separation of samples with concentrations as low as 0.1 ng·mL -1. The bioavailability of S-salbutamol was significantly higher than that of R-salbutamol after the different modes of administration. Stereoselective elimination was more pronounced after oral administration than after inhalation. Repeated inhalations resulted in successive increases in the S:R ratio as steady state was approached. In conclusion, the clinical consequences of increasing plasma concentrations of S-salbutamol need to be further assessed.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26742 (URN)11337 (Local ID)11337 (Archive number)11337 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    2. Metabolism of salbutamol differs between asthmatic patients and healthy volunteers
    Open this publication in new window or tab >>Metabolism of salbutamol differs between asthmatic patients and healthy volunteers
    Show others...
    2003 (English)In: Pharmacology and Toxicology, ISSN 0901-9928, E-ISSN 1600-0773, Vol. 92, no 1, p. 27-32Article in journal (Refereed) Published
    Abstract [en]

    Patients with asthma are a target group for medication with β2-agonists, often in combination with corticosteroids. Salbutamol is commonly marketed as racemate. R-Salbutamol carries β2-agonistic property whereas S-salbutamol does not. The racemate undergoes stereoselective sulphatisation by sulfotransferases mainly in the gut and liver, so that S-salbutamol rests for a longer time in the body and reaches higher plasma levels than R-salbutamol. Ten patients with mild stable asthma and at present without cortisone medication were given racemic salbutamol as ventoline 4 mg orally. Plasma and urine levels were estimated until 24 hr after ingestion. For comparison healthy volunteers were treated in the same way.The group of asthma patients was then treated with budesonide inhalations 800 μg daily for one week and the initial programme resumed. Non-cortisone-treated asthmatic patients displayed higher levels of both R- and S-salbutamol in plasma than did healthy volunteers after one single ingestion of racemic salbutamol (CMAX both comparisons P<0.05). Plasma levels of salbutamol isomers in cortisone-treated asthmatic patients resembled the levels in volunteers. The most plausible explanation for the discrepancy in values between asthmatic patients and volunteers is a defective metabolic function by asthmatic patients possibly enzymatic in origin.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26504 (URN)10.1034/j.1600-0773.2003.920105.x (DOI)11061 (Local ID)11061 (Archive number)11061 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    3. Preserved bronchial dilatation after salbutamol does not guarantee protection against bronchial hyperresponsiveness
    Open this publication in new window or tab >>Preserved bronchial dilatation after salbutamol does not guarantee protection against bronchial hyperresponsiveness
    2003 (English)In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 23, no 1, p. 14-20Article in journal (Refereed) Published
    Abstract [en]

    Racemic salbutamol, a β2-adrenoceptor agonist used for dilatation of airways, has recently been shown to induce lessened relaxation of bronchial smooth muscle and partial loss of bronchoprotection, seen as increased hyperresponsiveness, after regular treatment. The racemate undergoes stereo-selective disposition, giving higher plasma levels of S-salbutamol than that of bronchodilating R-salbutamol, thus raising S : R ratios after repeated administration. Our aim was to evaluate whether increased bronchial hyperresponsiveness (BHR) could be found even after 1 day of repeated salbutamol inhalations, with β2-receptor-induced bronchial smooth muscle relaxation remaining and whether this would be associated with plasma levels of either enantiomer. Fifteen patients with stable asthma, aged 19–54 years, were included in a randomized, cross-over study. An indirect bronchial challenge method was used [voluntary isocapnic hyperventilation of cold air (IHCA)], and airway condition tested by means of impulse oscillometry. Racemic salbutamol was inhaled three times during a 6-h period. IHCA was performed and plasma concentrations of enantiomers were measured 4 h after the last dose. Tests were also performed without preceding drug treatment. β2-Agonist-produced bronchial dilatation and protection persisted in the majority of the 15 patients 4 h after repeated inhalations of salbutamol during 1 day. In only two of the 15 patients we could trace increased BHR after salbutamol. Neither dilatation nor protection could be linked to plasma levels of either R- or S-salbutamol. The underlying mechanisms of BHR remain unknown and are dissociated from β2-receptor-mediated dilatation.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-26503 (URN)10.1046/j.1475-097X.2003.00462.x (DOI)11060 (Local ID)11060 (Archive number)11060 (OAI)
    Available from: 2009-10-08 Created: 2009-10-08 Last updated: 2017-12-13Bibliographically approved
    4. Single-isomer R-salbutamol is not superior to the racemate ragarding bronchial hyperreactivity
    Open this publication in new window or tab >>Single-isomer R-salbutamol is not superior to the racemate ragarding bronchial hyperreactivity
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Twenty-six patients with mild to moderate asthma were enrolled in a doubleblind, randomised, cross-over study. Bronchial response to provocation, given as isocapnic hyperventilation with cold air (IHCA), was measured before and after one week's medication with single isomer R-salbutamol and racemic R/S-salbutamol, respectively. Doses of 0.63 mg R-salbutamol or 1.25 mg R/S-salbutamol were inhaled by nebuliser three times daily dming medication-weeks. Impulse oscillometry (IOS) as well as forced expiratory volume dming one second (FEV1) were methods used to identify bronchial response to provocation. Two patients withdrew from the investigation due to side-effects, one from Rthe other from R,S-salbutamol.

    The aim of this study was to investigate the effects from medication with R,S- and R-salbutamol on bronchial response to provocation.

    Intra-individual differences of < 2% between days in baseline values, measured as total airway resistance (R5) by IOS and ≤ 1% measured as FEV1. indicated comparable resting bronchial conditions. After a week's medication no significant differences in airway responsiveness to provocation could be demonstrated irrespective of the medication used.

    Neither regular medication with inhaled corticosteroids up to 800 mg/day nor any increase in ahway inflammation, was found to influence the results.

    Plasmaconcentrations of R-salbutamol were intra-individually lower after R- than after R,S-salbutamol. Considerable amounts of S-salbutamol were retrieved in plasma after medication with pure R-salbutamol.

    We conclude that we were unable to demonstrate favourable effects of R-salbutamol over R,S-salbutamol regarding response to provocation with cold air after medication of one week's duration.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-81908 (URN)
    Available from: 2012-09-25 Created: 2012-09-25 Last updated: 2012-09-25Bibliographically approved
  • 186.
    Naidu Sjöswärd, Kerstin
    et al.
    Linköping University, Department of Medicine and Care, Anaesthesiology. Linköping University, Faculty of Health Sciences.
    Davidsson, Annette
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Schmekel, Birgitta
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Single-isomer R-salbutamol is not superior to the racemate ragarding bronchial hyperreactivityManuscript (preprint) (Other academic)
    Abstract [en]

    Twenty-six patients with mild to moderate asthma were enrolled in a doubleblind, randomised, cross-over study. Bronchial response to provocation, given as isocapnic hyperventilation with cold air (IHCA), was measured before and after one week's medication with single isomer R-salbutamol and racemic R/S-salbutamol, respectively. Doses of 0.63 mg R-salbutamol or 1.25 mg R/S-salbutamol were inhaled by nebuliser three times daily dming medication-weeks. Impulse oscillometry (IOS) as well as forced expiratory volume dming one second (FEV1) were methods used to identify bronchial response to provocation. Two patients withdrew from the investigation due to side-effects, one from Rthe other from R,S-salbutamol.

    The aim of this study was to investigate the effects from medication with R,S- and R-salbutamol on bronchial response to provocation.

    Intra-individual differences of < 2% between days in baseline values, measured as total airway resistance (R5) by IOS and ≤ 1% measured as FEV1. indicated comparable resting bronchial conditions. After a week's medication no significant differences in airway responsiveness to provocation could be demonstrated irrespective of the medication used.

    Neither regular medication with inhaled corticosteroids up to 800 mg/day nor any increase in ahway inflammation, was found to influence the results.

    Plasmaconcentrations of R-salbutamol were intra-individually lower after R- than after R,S-salbutamol. Considerable amounts of S-salbutamol were retrieved in plasma after medication with pure R-salbutamol.

    We conclude that we were unable to demonstrate favourable effects of R-salbutamol over R,S-salbutamol regarding response to provocation with cold air after medication of one week's duration.

  • 187.
    Naidu Sjöswärd, Kerstin
    et al.
    Linköping University, Department of Medicine and Care, Anaesthesiology. Linköping University, Faculty of Health Sciences.
    Josefsson, Martin
    Linköping University, Department of Molecular and Clinical Medicine, Forensic Medicine. Linköping University, Faculty of Health Sciences.
    Ahlner, Johan
    Linköping University, Department of Molecular and Clinical Medicine, Forensic Medicine. Linköping University, Faculty of Health Sciences.
    Andersson, Rolf
    Linköping University, Department of Medicine and Care, Pharmacology. Linköping University, Faculty of Health Sciences.
    Schmekel, Birgitta
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Metabolism of salbutamol differs between asthmatic patients and healthy volunteers2003In: Pharmacology and Toxicology, ISSN 0901-9928, E-ISSN 1600-0773, Vol. 92, no 1, p. 27-32Article in journal (Refereed)
    Abstract [en]

    Patients with asthma are a target group for medication with β2-agonists, often in combination with corticosteroids. Salbutamol is commonly marketed as racemate. R-Salbutamol carries β2-agonistic property whereas S-salbutamol does not. The racemate undergoes stereoselective sulphatisation by sulfotransferases mainly in the gut and liver, so that S-salbutamol rests for a longer time in the body and reaches higher plasma levels than R-salbutamol. Ten patients with mild stable asthma and at present without cortisone medication were given racemic salbutamol as ventoline 4 mg orally. Plasma and urine levels were estimated until 24 hr after ingestion. For comparison healthy volunteers were treated in the same way.The group of asthma patients was then treated with budesonide inhalations 800 μg daily for one week and the initial programme resumed. Non-cortisone-treated asthmatic patients displayed higher levels of both R- and S-salbutamol in plasma than did healthy volunteers after one single ingestion of racemic salbutamol (CMAX both comparisons P<0.05). Plasma levels of salbutamol isomers in cortisone-treated asthmatic patients resembled the levels in volunteers. The most plausible explanation for the discrepancy in values between asthmatic patients and volunteers is a defective metabolic function by asthmatic patients possibly enzymatic in origin.

  • 188.
    Naidu Sjöswärd, Kerstin
    et al.
    Linköping University, Department of Medicine and Care, Anaesthesiology. Linköping University, Faculty of Health Sciences.
    Josefsson, Martin
    Linköping University, Department of Molecular and Clinical Medicine, Forensic Medicine. Linköping University, Faculty of Health Sciences.
    Ahlner, Johan
    Linköping University, Department of Molecular and Clinical Medicine, Forensic Medicine. Linköping University, Faculty of Health Sciences.
    Schmekel, Birgitta
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Preserved bronchial dilatation after salbutamol does not guarantee protection against bronchial hyperresponsiveness2003In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 23, no 1, p. 14-20Article in journal (Refereed)
    Abstract [en]

    Racemic salbutamol, a β2-adrenoceptor agonist used for dilatation of airways, has recently been shown to induce lessened relaxation of bronchial smooth muscle and partial loss of bronchoprotection, seen as increased hyperresponsiveness, after regular treatment. The racemate undergoes stereo-selective disposition, giving higher plasma levels of S-salbutamol than that of bronchodilating R-salbutamol, thus raising S : R ratios after repeated administration. Our aim was to evaluate whether increased bronchial hyperresponsiveness (BHR) could be found even after 1 day of repeated salbutamol inhalations, with β2-receptor-induced bronchial smooth muscle relaxation remaining and whether this would be associated with plasma levels of either enantiomer. Fifteen patients with stable asthma, aged 19–54 years, were included in a randomized, cross-over study. An indirect bronchial challenge method was used [voluntary isocapnic hyperventilation of cold air (IHCA)], and airway condition tested by means of impulse oscillometry. Racemic salbutamol was inhaled three times during a 6-h period. IHCA was performed and plasma concentrations of enantiomers were measured 4 h after the last dose. Tests were also performed without preceding drug treatment. β2-Agonist-produced bronchial dilatation and protection persisted in the majority of the 15 patients 4 h after repeated inhalations of salbutamol during 1 day. In only two of the 15 patients we could trace increased BHR after salbutamol. Neither dilatation nor protection could be linked to plasma levels of either R- or S-salbutamol. The underlying mechanisms of BHR remain unknown and are dissociated from β2-receptor-mediated dilatation.

  • 189.
    Naidu Sjöswärd, Kerstin
    et al.
    Linköping University, Department of Medicine and Care. Linköping University, Faculty of Health Sciences.
    Uppugunduri, Srinivas
    Linköping University, Department of Medicine and Care. Linköping University, Faculty of Health Sciences.
    Schmekel, Birgitta
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Decreased serum levels of P-selectin and eosinophil cationic protein in patients with mild asthma after inhaled salbutamol2004In: Respiration, ISSN 0025-7931, E-ISSN 1423-0356, Vol. 71, no 3, p. 241-245Article in journal (Refereed)
    Abstract [en]

    Background: Asthma is a chronic inflammatory disease of the airways associated with selective recruitment of activated eosinophils. P-selectin, a cell adhesion molecule, may be an important controller of the inflammation by mediating selective eosinophil cell influx to the lung. Serum levels of eosinophil cationic protein (ECP) have been used as a marker of eosinophil inflammation, and indirectly as a marker of disease activity of asthma. ECP levels may not be elevated in some patients with asthma, and this fact prompted us to search for additional surrogate markers for monitoring disease activity in asthma. Objectives: To evaluate whether repeated inhalations of salbutamol, a ß-2-receptor agonist used for bronchodilation, would lead to reduced serum levels of P-selectin and/or ECP. Methods: Fourteen patients with asymptomatic mild stable asthma were enrolled into a randomised crossover study. Salbutamol was inhaled three times every 3 h. Blood was sampled 4 h after the last inhalation. Nine non-treated healthy volunteers served as control subjects. Serum ECP and P-selectin levels were measured using radioimmunoassay and ELISA, respectively. Results: P-selectin and ECP levels in serum obtained from asymptomatic asthmatics were close to those of the volunteers, and inter-day variability tended to be lower for levels of P-selectin than for ECP. Significant decreases of P-selectin (p = 0.01) and ECP (p = 0.03) were recorded after salbutamol inhalation. There was no association between the changes in ECP and P-selectin levels in serum. Conclusions: We conclude that decreases in P-selectin and ECP may have different kinetics, suggesting different pathways of action of salbutamol. We judge that P-selectin may be used as a sensitive marker in mild asthma. Copyright © 2004 S. Karger AG, Basel.

  • 190.
    Naidu-Sjöswärd, Kerstin
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Anaesthesiology. Östergötlands Läns Landsting, Anaesthesiology and Surgical Centre, Department of Intensive Care UHL.
    Mounira, H
    Davidsson, Anette
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Söderkvist, Peter
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Biomedicine and Surgery, Division of cell biology.
    Schmekel, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Single-isomer R-salbutamol is not superior to racemate regarding protection for bronchial hyperresponsiveness2004In: Respiratory Medicine, ISSN 0954-6111, E-ISSN 1532-3064, Vol. 98, no 10, p. 990-Article in journal (Refereed)
    Abstract [en]

    Bronchial hyper-reactivity (BHR) has been suggested to follow cessation of regular medication with racemic salbutamol. This study aimed at investigating the effects from medication with R,S- and R-salbutamol on bronchial response to provocation with isocapnic hyperventilation of cold air (IHCA). Twenty-six patients with mild to moderate asthma were enrolled in a double-blind, randomised, cross-over study. Bronchial response to provocation was measured before and after 1 week's medication. Doses of 0.63 mg R-salbutamol or 1.25 mg R/S-salbutamol were inhaled three times daily during medication-weeks and a wash-out week intervened. Tests were performed 6 h after the last dose of test drug. Impulse oscillometry and forced expiratory volume during one second were methods used to identify bronchial response to provocation. Two patients withdrew from the investigation due to side-effects, one from R- the other from R,S-salbutamol. Comparable resting bronchial conditions were indicated by differences in baseline lung function values of <2% between study days. No statistically significant medication-dependent differences in BHR could be demonstrated between treatment groups. However, 15 patients exhibited higher (P=0.03) post-treatment BHR after pure R-salbutamol than after R,S-salbutamol. Furthermore, plasma concentrations of R-salbutamol tended to be lower (P=0.08) after medication with R- than after R,S-salbutamol despite equal doses of R-salbutamol given during the two separate treatment periods. We also found that considerable amounts of S-salbutamol were retrieved in plasma after medication with pure R-salbutamol. We conclude that we were unable to demonstrate favourable effects of R-salbutamol over R,S-salbutamol regarding response to provocation with IHCA after regular medication of 1 week's duration.

  • 191.
    Neider, Daniel
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Hallman, Daniel
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Zachrisson, Helene
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Lindenberger, Marcus
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology.
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Venous compliance in the Superficial Femoral Vein and Greater Saphenous Vein in health males.2007In: Kardiovaskulära vårmötet,2007, 2007Conference paper (Other academic)
    Abstract [en]

      

  • 192.
    Nelson, Nina
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Pediatrics. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Barn.
    Janerot-Sjöberg, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Beat-to-beat changes in stroke volume precede the general circulatory effects of mechanical ventilation: A case report2001Article in journal (Refereed)
    Abstract [en]

    Background: The haemodynamic as well as the ventilatory consequences of mechanical ventilation can be harmful in critically ill neonates. Newly developed ventilatory lung protective strategies are not always available immediately and in an acute situation the haemodynamic changes caused by mechanical ventilation can affect the oxygen delivery considerably. We report the case of a male neonate who was treated with conventional pressure-controlled mechanical ventilation because of respiratory distress and progressive respiratory acidosis resulting from meconium aspiration. Because of poor arterial oxygenation despite 100% inspired oxygen and increased ventilator settings, echocardiography was performed to exclude central haemodynamic reasons for low oxygen delivery. Method: Doppler echocardiography was used for the measurement of stroke volume and cardiac output. Pulse oximetry and aortic blood pressure were monitored continuously. Results: Echocardiography revealed no cardiac malformations or signs of persistent fetal circulation. When inspiratory pressures and duration were increased, beat-to-beat variation in stroke volume preceded decay in cardiac output. Stroke volume variations and oxygen saturation values guided ventilator settings until extracorporal membrane oxygenation could be arranged for. After recovery and discharge 4 weeks later the boy is progressing normally. Conclusion: Because oxygen delivery is dependent on both blood flow and arterial oxygen content, measurement of cardiac output as well as left heart oxygen saturation is a useful guide to optimizing oxygen delivery. This case report demonstrates how Doppler echocardiographic monitoring of beat-to-beat changes in stroke volume can be used to detect early negative haemodynamic effects of increased mechanical ventilation settings before cardiac output is affected.

  • 193.
    Nelson, Nina
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Pediatrics. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Barn.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Neonatal ventricular hypertrophy without cardiac malformations: A retrospective evaluation of 17 infants2001In: Prenatal and Neonatal Medicine, ISSN 1359-8635, E-ISSN 1473-0774, Vol. 6, no 5, p. 318-322Article in journal (Refereed)
    Abstract [en]

    Cardiac hypertrophy in the neonatal period is usually associated with other congenital defects of the circulatory system. Isolated ventricular hypertrophy can be difficult to evaluate and manage. We present 17 neonates with increased ventricular wall thickness without congenital malformations according to echocardiography during the neonatal period. The echocardiographic findings were defined as either concentric or predominantly septal hypertrophy. Doppler signs of ventricular outflow obstruction were found in six babies. The material consisted of preterm infants with steroid-treated bronchopulmonary dysplasia, metabolic disorders, perinatal infections, hypertrophic cardiomyopathy and babies with no identified underlying disorder. Six out of 17 patients died before the age of 8 months: all three babies with hypertrophic cardiomyopathy, one with toxoplasmosis and two out of four infants with steroid-treated bronchopulmonary dysplasia. It was not possible to predict the outcome from the initial clinical examination or from the first echocardiographic investigation. Ventricular wall thickness and outflow obstruction may undergo significant and rapid changes, and thus we recommend repeated echocardiographic examinations.

  • 194.
    Neumark, Thomas
    et al.
    Linköping University, Department of Department of Health and Society, General Practice. Linköping University, Faculty of Health Sciences. Lindsdal Primary Health Centre, Kalmar, Sweden.
    Mölstad, Sigvard
    Linköping University, Department of Department of Health and Society, General Practice. Linköping University, Faculty of Health Sciences. Unit of Research and Development in Primary care, Jönköping.
    Rosén, Christer
    Department of Oto-Rhino-Laryngology, Kalmar County Hospital, Kalmar.
    Persson, Lars-Göran
    Unit of Research and Development in Primary care, Jönköping.
    Törngren, Annika
    Department of Oto-Rhino-Laryngology, Kalmar County Hospital, Kalmar.
    Brudin, Lars
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Eliasson, Ingvar
    Department of Clinical Microbiology and Immunology, Lund University Hospital, Lund, Sweden.
    Evaluation of phenoxymethylpenicillin treatment of acute otitis media in children aged 2-162007In: Scandinavian Journal of Primary Health Care, ISSN 0281-3432, E-ISSN 1502-7724, Vol. 25, no 3, p. 166-171Article in journal (Refereed)
    Abstract [en]

    Objective. To study the clinical recovery from acute otitis media (AOM) in children, 2-16 years of age, managed with or without treatment with phenoxymethylpenicillin (PcV).

    Design. An open, prospective randomized trial. Children aged between 2 and 16 years, presenting with one- or double-sided AOM (without perforation) with symptom duration of less than four days, were included. The children were randomized to PcV for five days or to no primary antibiotic treatment. A health score and compliance were registered on a daily basis for seven days. Setting. A total of 32 health centres and 72 GPs in south-east Sweden.

    Subjects. Children aged 2-16 presenting with earache. Main outcome measures. Recovery time, symptom duration, frequency of complications (up to three months) and consumption of healthcare services independent of treatment with or without antibiotics.

    Results. A total of 179 patients carried out the trial, 92 were randomized to PcV, 87 to no primary antibiotic treatment. The median recovery time was four days in both groups. Patients who received PcV had less pain (p <0.001) and used fewer analgesics. There were no significant differences in the number of middle-ear effusions or perforations at the final control after three months. Children randomized to PcV treatment consulted less (p <0.001) during the first seven days.

    Conclusions. Our investigation supports that PcV treatment of AOM does not affect the recovery time or complication rates. PcV provided some symptomatic benefit in the treatment of AOM in otherwise healthy children, aged 2-16 years.

  • 195. Nguyen, TC
    et al.
    Carlhäll, Carljohan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Itoh, A
    Oakes, RA
    Ennis, DB
    Boothe, W
    Liang, D
    Daughters, GT
    Ingels, NB
    Miller, DC
    Alterations in transmural myocardial strain: an early marker of left ventricular dysfunction in mitral regurgitation?2007In: Circulation,2007, 2007Conference paper (Refereed)
    Abstract [en]

      116: II-368 

  • 196.
    Nielsen, Magnus
    et al.
    Malmö.
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ohlsson, Mattias
    Holst, Holger
    Thorsson, Ola
    Edenbrandt, Lars
    Interpretation of captopril renography using artificial neural networks2005In: Clinical Physiology and Functional Imaging, ISSN 1475-0961, E-ISSN 1475-097X, Vol. 25, no 5, p. 293-296Article in journal (Refereed)
    Abstract [en]

    The purpose of this study was to develop a method based on artificial neural networks for interpretation of captopril renography tests for the detection of renovascular hypertension caused by renal artery stenosis and to assess the value of different measurements from the test. A total of 250 99mTc-MAG3 captopril renography tests were used in the study. The material was collected from two different patient groups. One group consisted of 101 patients who also had undergone a renal angiography. The angiographies, which were used as gold standard, showed a significant renal artery stenosis in 53 of the 101 cases. The second group consisted of 149 patients, who's captopril renography tests all were interpreted as not compatible with significant renal artery stenosis by an experienced nuclear medicine physician. Artificial neural networks were trained for the diagnosis of renal artery stenosis using eight measures from each renogram. The neural network was then evaluated in separate test groups using an eightfold cross validation procedure. The performance of the neural networks, measured as the area under the receiver operating characteristic curve, was 0.93. The sensitivity was 91% at a specificity of 90%. The lowest performance was found for the network trained without use of a parenchymal transit measure, indicating the importance of this feature. Artificial neural networks can be trained to interpret captopril renography tests for detection of renovascular hypertension caused by renal artery stenosis. The result almost equals that of human experts shown in previous studies. © 2005 Blackwell Publishing Ltd.

  • 197.
    Nilsson, Kerstin
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Monryd, Lena
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Kidney depth and determination of realtive renal function2002In: European Journal of Nuclear Medicine,2002, 2002, p. 194-194Conference paper (Refereed)
  • 198. Nilsson, S
    et al.
    Engblom, D
    Karlsson, LG
    Mölstad, S
    Jönköping.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Scheike, M
    Åkerlind, Ingemar
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Department of Health and Society, National Centre for Work and Rehabilitation.
    Örtoft, K
    Bröstsmärta och ischemisk hjärtsjukdom i primärvården2002In: Svenska Läkaresällskapets Riksstämma, Göteborg, 2002,2002, 2002Conference paper (Refereed)
  • 199.
    Norberg Spaak, L
    et al.
    Östergötlands Läns Landsting, RC - Rekonstruktionscentrum, ÖNH - Öron- Näsa- Halskliniken.
    Granerus, Göran
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Gustafsson, A
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Radio Physics. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Radiation Physics.
    XVII World Congress IFOS Cairo, Egypt 2002Preliminary experiences of gamma camera-PET in patients with head and neck or lung cancer2002In: Rapportklass C eller D samt Impactvärde 0,000 sätts om ISSN inte kan uppges.,2002, 2002Conference paper (Refereed)
  • 200.
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Svenska riktlinjer (Idrottshjärtat och screening - svenska riktlinjer och hur gör vi?)2007In: IX Svenska Kardiovaskulära vårmötet,2007, 2007Conference paper (Other academic)
123456 151 - 200 of 294
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