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  • 1. Bech-Hansen, Odd
    et al.
    Caidahl, Kenneth
    Wallentin, Ingemar
    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.
    Assessment of effective orifice area of prosthetic aortic valves with Doppler echocardiography: An in vivo and in vitro study2001In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 122, no 2, p. 287-295Article in journal (Refereed)
    Abstract [en]

    Objectives: We sought to evaluate the Doppler assessment of effective orifice area in aortic prosthetic valves. The effective orifice area is a less flow-dependent parameter than Doppler gradients that is used to assess prosthetic valve function. However, in vivo reference values show a pronounced spread of effective orifice area and smaller orifices than expected compared with the geometric area. Methods: Using Doppler echocardiography, we studied patients who received a bileaflet St Jude Medical valve (n = 75, St Jude Medical, Inc, St Paul, Minn) or a tilting disc Omnicarbon valve (n = 46, Medical CV, Incorporated, Inver Grove Heights, Minn). The prosthetic valves were also investigated in vitro in a steady flow model with Doppler and catheter measurements in the different orifices. The effective orifice area was calculated according to the continuity equation. Results: In vivo, there was a wide distribution with the coefficient of variation (SD/mean ╫ 100%) for different valve sizes ranging from 21% to 39% in the St Jude Medical valve and from 25% to 33% in the Omnicarbon valve. The differences between geometric orifice area and effective orifice area in vitro were 1.26 ▒ 0.41 cm2 for St Jude Medical and 1.17 ▒ 0.38 cm2 for Omnicarbon valves. The overall effective orifice areas and peak catheter gradients were similar: 1.35 ▒ 0.37 cm2 and 25.9 ▒ 16.1 mm Hg for St Jude Medical and 1.46 ▒ 0.49 cm2 and 24.6 ▒ 17.7 mm Hg for Omnicarbon. However, in St Jude Medical valves, more pressure was recovered downstream, 11.6 ▒ 6.3 mm Hg versus 3.4 ▒ 1.6 mm Hg in Omnicarbon valves (P = .0001). Conclusions: In the patients, we found a pronounced spread of effective orifice areas, which can be explained by measurement errors or true biologic variations. The in vitro effective orifice area was small compared with the geometric orifice area, and we suspect that nonuniformity in the spatial velocity profile causes underestimation. The St Jude Medical and Omnicarbon valves showed similar peak catheter gradients and effective orifice areas in vitro, but more pressure was recovered in the St Jude Medical valve. The effective orifice area can therefore be misleading in the assessment of prosthetic valve performance when bileaflet and tilting disc valves are compared.

  • 2.
    Bothe, Wolfgang
    et al.
    Stanford University School of Medicine, Stanford, Calif.
    Kvitting, John-Peder Escobar
    Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Stephens, Elisabeth H.
    Rice University, Houston, Tex.
    Swanson, Julia C.
    Stanford University School of Medicine, Stanford, Calif.
    Liang, David H.
    Stanford University School of Medicine, Stanford, Calif.
    Ingels, Niel B.
    Stanford University School of Medicine, Stanford, Calif.
    Miller, D. Craig
    Stanford University School of Medicine, Stanford, Calif.
    Effects of different annuloplasty ring types on mitral leaflet tenting area during acute myocardial ischemia2011In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 141, no 2, p. 345-353Article in journal (Refereed)
    Abstract [en]

    Objective

    The study objective was to quantify the effects of different annuloplasty rings on mitral leaflet septal-lateral tenting areas during acute myocardial ischemia.

    Methods

    Radiopaque markers were implanted along the central septal-lateral meridian of the mitral valve in 30 sheep: 1 each to the septal and lateral aspects of the mitral annulus and 4 and 2 along the anterior and posterior mitral leaflets, respectively. Ten true-sized Carpentier-Edwards Physio, Edwards IMR ETLogix, and GeoForm annuloplasty rings (Edwards Lifesciences, Irvine, Calif) were inserted in a releasable fashion. Marker coordinates were obtained using biplane videofluoroscopy with ring inserted at baseline (RING_BL) and after 90 seconds of left circumflex artery occlusion (RING_ISCH). After ring release, another dataset was acquired before (No_Ring_BL) and after left circumflex artery occlusion (No_Ring_ISCH). Anterior and posterior mitral leaflet tenting areas were computed at mid-systole from sums of marker triangles with the midpoint between the annular markers being the vertex for all triangles.

    Results

    Compared with No_Ring_BL, mitral regurgitation grades and all tenting areas significantly increased with No_Ring_ISCH. Compared with No_Ring_ISCH, (1) all rings significantly prevented mitral regurgitation and reduced all tenting areas; (2) Edwards IMR ETLogix and GeoForm rings reduced posterior mitral leaflet area, but not anterior mitral leaflet tenting area, to a significantly greater extent than the Carpentier-Edwards Physio ring; and (3) Edwards IMR ETLogix and GeoForm rings affected tenting areas similarly.

    Conclusions

    In response to acute left ventricular ischemia, disease-specific functional/ischemic mitral regurgitation rings (Edwards IMR ETLogix, GeoForm) more effectively reduced posterior mitral leaflet area, but not anterior mitral leaflet tenting area, compared with true-sized physiologic rings (Carpentier-Edwards Physio). Despite its radical 3-dimensional shape and greater amount of mitral annular septal-lateral downsizing, the GeoForm ring did not reduce tenting areas more than the Edwards IMR ETLogix ring, suggesting that further reduction in tenting areas in patients with FMR/IMR may not be effectively achieved on an annular level.

  • 3.
    Chang-Chun, Chen
    et al.
    Katholieke Universiteit Leuven, Belgium.
    Masuda, Munetaka
    Katholieke Universiteit Leuven, Belgium.
    Szabó, Zoltán
    Katholieke Universiteit Leuven, Belgium.
    Szerafin, T
    Szecsi, J
    Katholieke Universiteit Leuven, Belgium.
    Van Belle, Herman
    Janssen Research Foundation, Beerse, Belgium.
    Flameng, Willem
    Katholieke Universiteit Leuven, Belgium.
    Nucleoside transport inhibition mediates lidoflazine-induced cardioprotection during intermittent aortic crossclamping1992In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 104, no 6, p. 1602-1609Article in journal (Refereed)
    Abstract [en]

    The effects of pretreatment with the nucleoside transport inhibitor lidoflazine on repeated ischemia-reperfusion injury induced by normothermic intermittent aortic crossclamping were studied in canine hearts. Eighteen mongrel dogs were allocated to three groups: placebo (n = 6), lidoflazine (1 mg/kg) (n = 6), and lidoflazine (1 mg/kg) plus the adenosine receptor blocker aminophylline (7 mg/kg) (n = 6). Pretreatment was performed intravenously during 15 minutes before extracorporeal circulation. All hearts were subjected to four intervals of 15 minutes of global ischemia each followed by 10 minutes of reperfusion. After weaning from extracorporeal circulation, functional recovery was followed for 1 hour. In the lidoflazine group, myocardial adenosine content (0.25 +/- 0.06 mumol/gm dry weight) was 3.5 times higher than that in the control group (0.07 +/- 0.03 mumol/gm dry weight; p < 0.05) at the end of the last aortic crossclamping. The release of adenosine from the myocardium during each reperfusion period was significantly higher than that in the control group (p < 0.05). Myocardial extraction of lactate was normalized at every reperfusion interval in the lidoflazine group but not in the control group (p < 0.05). In the lidoflazine group functional recovery was significantly better than that in the control group. Positive rate of rise of pressure, negative rate of rise of pressure, and cardiac output recovered to, respectively, 150% +/- 19%, 82% +/- 8%, and 131% +/- 15% in the lidoflazine group versus, respectively, 37% +/- 9%, 23% +/- 7%, and 29% +/- 8% in the control group (p < 0.001) at 1 hour after extracorporeal circulation. When the adenosine receptor blocker aminophylline was administered in association with lidoflazine, protection dropped significantly: positive and negative rate of rise of pressure and cardiac output were, respectively, 58% +/- 8%, 46% +/- 9%, and 67% +/- 16% at 1 hour after extracorporeal circulation (p < 0.05 versus lidoflazine alone). These results suggest that the cardioprotective effects of lidoflazine are at least in part mediated by adenosine receptor stimulation via nucleoside transport inhibition-induced accumulation of endogenous adenosine in the myocardium.

  • 4.
    Escobar Kvitting, John-Peder
    et al.
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Ebbers, Tino
    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.
    Engvall, Jan
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences.
    Olin, Christian L.
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Bolger, Ann F.
    Department of Medicine, University of California San Francisco, San Francisco, Calif, USA.
    Flow patterns in the aortic root and the aorta studied with time-resolved, 3-dimensional, phase-contrast magnetic resonance imaging: implications for aortic valve–sparing surgery2004In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 127, no 6, p. 1602-1607Article in journal (Refereed)
    Abstract [en]

    Objective

    Sparing the aortic valve has become a surgical option for patients who require repair of aortic root ectasia and have normal valve leaflets. Surgical approaches to valve sparing differ with regard to preservation of the native sinuses of Valsalva. The role of the sinuses and the importance of maintaining them remain controversial.

    Methods

    By using a time-resolved, 3-dimensional, phase-contrast magnetic resonance imaging technique, aortic root and aortic blood velocity data were acquired from 2 patients with Marfan syndrome 6 months after aortic valve–sparing surgery with straight Dacron grafts and contrasted with data from 6 normal volunteers.

    Results

    In normal aortas vortical blood flow became apparent in the individual sinuses after peak systole. The vortices filled the available space behind the valve leaflets and persisted until diastole, expanding and moving inward during aortic valve closure. In contrast, no vortices were observed in the postoperative patients with Marfan syndrome with negligible sinuses.

    Conclusions

    Changes in supravalvular flow accompany loss of sinus architecture. Whether the presence, size, and velocity of supravalvular vortices affects the function or durability of the preserved aortic valve remains to be studied.

  • 5.
    Escobar Kvitting, John-Peder
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Engvall, Jan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Broqvist, Mats
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    FranzÉn, Stefan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Andersson, Mats
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Neurology. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Ohlsson, Ulf
    Department of Medicine Oskarshamns Hospital.
    Nielsen, Niels Erik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medical and Health Sciences, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Recurrence of myxoma in the left ventricle with concurrent cerebral fusiform aneurysms after previous atrial myxoma surgery2008In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 135, no 5, p. 1172-1173Article in journal (Other academic)
  • 6.
    Gaipov, Abduzhappar
    et al.
    Natl Sci Med Res Ctr, Kazakhstan.
    Molnar, Miklos Z.
    Methodist Univ Hosp, TN USA; Semmelweis Univ, Hungary.
    Potukuchi, Praveen K.
    Natl Sci Med Res Ctr, Kazakhstan.
    Sumida, Keiichi
    Natl Sci Med Res Ctr, Kazakhstan; Toranomon Hosp Kajigaya, Japan.
    Canada, Robert B.
    Natl Sci Med Res Ctr, Kazakhstan.
    Akbilgic, Oguz
    Kazakh Natl Med Univ, Kazakhstan.
    Kabulbayev, Kairat
    Kazakh Natl Med Univ, Kazakhstan.
    Szabo, Zoltán
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Koshy, Santhosh K. G.
    Univ Tennessee, TN 38104 USA.
    Kalantar-Zadeh, Kamyar
    Univ Calif Irvine, CA 92668 USA.
    Kovesdy, Csaba P.
    Natl Sci Med Res Ctr, Kazakhstan; Memphis VA Med Ctr, TN 38104 USA.
    Predialysis coronary revascularization and postdialysis mortality2019In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 157, no 3, p. 976-+Article in journal (Refereed)
    Abstract [en]

    Objectives: Coronary artery bypass grafting (CABG) is associated with better survival than percutaneous coronary intervention (PCI) in patients with mild-to-moderate chronic kidney disease (CKD) and end-stage renal disease (ESRD). However, the optimal strategy for coronary artery revascularization in patients with advanced CKD who transition to ESRD is unclear. Methods: We examined a contemporary national cohort of 971 US veterans with incident ESRD who underwent first CABG or PCI up to 5 years before dialysis initiation. We examined the association of a history of CABG versus PCI with all-cause mortality following transition to dialysis using Cox proportional hazards models adjusted for time between procedure and dialysis initiation, sociodemographics, comorbidities, and medications. Results: In total, 582 patients underwent CABG and 389 patients underwent PCI. The mean age was 64 +/- 8 years, 99% of patients were male, 79% were white, 19% were African American, and 84% had diabetes. The all-cause post-dialysis mortality rates after CABG and PCI were 229 per 1000 patient-years (95% confidence interval [CI], 205-256) and 311 per 1000 patient years (95% CI, 272-356), respectively. Compared with PCI, patients who underwent CABG had 34% lower risk of death (multivariable adjusted hazard ratio, 0.66; 95% CI, 0.51-0.86, P = .002) after initiation of dialysis. Results were similar in all subgroups of patients stratified by age, race, type of intervention, presence/absence of myocardial infarction, congestive heart failure, and diabetes. Conclusions: CABG in patients with advanced CKD was associated lower risk of death after initiation of dialysis compared with PCI.

  • 7.
    Ihlberg, Leo
    et al.
    Helsinki University Hospital, Finland .
    Nissen, Henrik
    Odense University Hospital, Denmark .
    Nielsen, Niels Erik
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Cardiology in Linköping.
    Rueck, Andreas
    Karolinska University Hospital, Sweden .
    Busund, Rolf
    University Hospital North Norway, Norway .
    Klaarborg, Kaj-Erik
    Aarhus University Hospital, Denmark .
    Soendergaard, Lars
    Rigshosp, Denmark .
    Harnek, Jan
    University of Lund Hospital, Sweden .
    Miettinen, Heikki
    Kuopio University Hospital, Finland .
    Eskola, Markku
    Tampere University Hospital, Finland .
    Wahba, Alexander
    Norwegian University of Science and Technology, Norway .
    Laine, Mika
    Helsinki University Hospital, Finland .
    Early clinical outcome of aortic transcatheter valve-in-valve implantation in the Nordic countries2013In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 146, no 5, p. 1047-1054Article in journal (Refereed)
    Abstract [en]

    Objective: Transcatheter valve-in-valve implantation has emerged as an option, in addition to reoperative surgical aortic valve replacement, to treat failed biologic heart valve substitutes. However, the clinical experience with this approach is still limited. We report the comprehensive experience of transcatheter valve-in-valve implantation in the Nordic countries from May 2008 to January 2012. less thanbrgreater than less thanbrgreater thanMethods: A total of 45 transcatheter aortic valve-in-valve implantations were performed during the study period in 11 centers. The mean age of the patients was 80.6 years (range, 61-91), 26 were male and 19 were female, and the mean EuroSCORE, EuroSCORE II, and Society of Thoracic Surgeons score was 35.4, 16.3, and 14.6, respectively. The type of failure was stenosis and combined in 58% (mean and peak aortic valve gradient, 77 and 45 mm Hg, respectively) and regurgitation in 42% of cases. The SAPIEN/XT (Edwards LifeSciences, Irvine, Calif) and CoreValve (Medtronic Inc, Minneapolis, Minn) system was used in 33 and 12 cases, respectively. The access route was transapical in 25, transfemoral in 17, transaortic in 2, and subclavian in 1 case. The mean follow-up was 14.4 months. The periprocedural and postoperative outcomes were assessed using the Valve Academic Research Consortium criteria. less thanbrgreater than less thanbrgreater thanResults: No intraprocedural mortality occurred. The technical success rate was 95.6% (1 second valve implantation, 1 conversion to open surgery). The all-cause 30-day mortality was 4.4% (1 cardiac-related and 1 aspiration pneumonia). The major complications within 30 days included stroke in 2.2%, periprocedural myocardial infarction in 4.4%, and major vascular complication in 2.2% of patients. At 1 month, all but 1 patient had either no or mild paravalvular leakage, with a mean and peak valve gradient of 17 mm Hg (range, 4-38) and 30 mm Hg (range, 7-68), respectively. The mean gradient was greater than 20 mm Hg in 17% of patients and remained unchanged at 12 months. The 1-year survival was 88.1%. less thanbrgreater than less thanbrgreater thanConclusions: Transcatheter valve-in-valve implantation is widely performed, albeit in small numbers, in most centers in the Nordic countries. The short-termresults were excellent in this high-risk patient population, demonstrating a low incidence of device-or procedure-related complications. However, a considerable number of patients were left with suboptimal systolic valve performance with unknown long-term effects, warranting close surveillance after transcatheter valve-in-valve implantation.

  • 8.
    Jackson, Veronica
    et al.
    Karolinska Institutet, Stockholm, Sweden.
    Olsson, Therese
    Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
    Kurtovic, Sanela
    Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
    Folkersen, Lasse
    Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
    Paloschi, Valentina
    Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
    Wågsäter, Dick
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences. Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
    Franco-Cereceda, Anders
    Karolinska Institutet, Stockholm, Sweden.
    Eriksson, Per
    Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden.
    Matrix metalloproteinase 14 and 19 expression is associated with thoracic aortic aneurysms2012In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 144, no 2, p. 459-466Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE:

    It is hypothesized that an altered turnover of extracellular matrix mediated by matrix metalloproteinases (MMPs) is present in thoracic aortic aneurysms. Here, we analyzed the occurrence of MMPs and MMP inhibitors in ascending aortic aneurysms in patients with bicuspid and tricuspid aortic valves.

    METHODS:

    Expression of 23 MMPs and their inhibitors was measured in aortic intima/media and adventitia in 109 patients (40 tricuspid, 69 bicuspid, 68 with aortic diameter≥4.5 cm, and 41 with ≤4.0 cm) using Affymetrix Exon arrays (Affymetrix, Santa Clara, Calif). Gene expression was confirmed by quantitative real-time polymerase chain reaction. Principal components analysis was used to study differences in gene expression. Immunohistochemistry was used to study protein expression.

    RESULTS:

    We detected messenger RNA expression for gelatinases (MMP2 and MMP9), stromelysin 3 (MMP11), all membrane bound MMPs (MMP14, MMP15, MMP16, MMP17, MMP24, MMP25), MMP19, MMP21, and MMP28 in ascending aorta. No expression of collagenases was detected. Principal components analysis showed that changes in mRNA expression between dilated and nondilated aorta were mainly detected in patients with tricuspid aortic valves. MMP14 and MMP19 showed higher expression in dilated aortas and MMP19 expression correlated positively to maximal aortic diameter in patients with tricuspid aortic valves (Rho=0.61, P=.004, and Rho=0.57, P=.008, using raw and body surface area-corrected aortic diameter, respectively). Immunohistochemical staining demonstrated increased medial expression of MMP14 and MMP19 in dilated aorta.

    CONCLUSIONS:

    The present study identifies MMP14 and MMP19 as proteolytic enzymes potentially involved in aneurysm formation in the ascending aorta of patients with tricuspid aortic valves

  • 9.
    Nguyen, Tom c.
    et al.
    Stanford University.
    Itoh, Akinobu
    Stanford University.
    Carlhäll, Carljohan
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Bothe, Wolfgang
    Stanford University.
    Timek, Tomasz A
    Stanford University.
    Ennis, Daniel B
    Stanford University.
    Oakes, Robert A
    Stanford University.
    Liang, David
    Stanford University.
    Daughters, George T.
    Stanford University.
    Ingels, Neil B
    Stanford University.
    Miller, D. Craig
    Stanford University.
    The effect of pure mitral regurgitation on mitral annular geometry and three-dimensional saddle shape2008In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 136, no 3, p. 557-565Article in journal (Refereed)
    Abstract [en]

    Objective: Chronic ischemic mitral regurgitation is associated with mitral annular dilatation in the septal-lateral dimension and flattening of the annular 3-dimensional saddle shape. To examine whether these perturbations are caused by the ischemic insult, mitral regurgitation, or both, we investigated the effects of pure mitral regurgitation (low pressure volume overload) on annular geometry and shape. Methods: Eight radiopaque markers were sutured evenly around the mitral annulus in sheep randomized to control (CTRL, n = 8) or experimental (HOLE, n = 12) groups. In HOLE, a 3.5- to 4.8-mm hole was punched in the posterior leaflet to generate pure mitral regurgitation. Four-dimensional marker coordinates were obtained radiographically 1 and 12 weeks postoperatively. Mitral annular area, annular septal-lateral and commissure-commissure dimensions, and annular height were calculated every 16.7 ms. Results: Mitral regurgitation grade was 0.4 ± 0.4 in CTRL and 3.0 ± 0.8 in HOLE (P < .001) at 12 weeks. End-diastolic left ventricular volume index was greater in HOLE at both 1 and 12 weeks, end-systolic volume index was larger in HOLE at 12 weeks. Mitral annular area increased in HOLE predominantly in the commissure-commissure dimension, with no difference in annular height between HOLE versus CTRL at 1 or 12 weeks, respectively. Conclusion: In contrast with annular septal-lateral dilatation and flattening of the annular saddle shape observed with chronic ischemic mitral regurgitation, pure mitral regurgitation was associated with commissure-commissure dimension annular dilatation and no change in annular shape. Thus, infarction is a more important determinant of septal-lateral dilatation and annular shape than mitral regurgitation, which reinforces the need for disease-specific designs of annuloplasty rings. © 2008 The American Association for Thoracic Surgery.

  • 10.
    Stephens, Elizabeth H.
    et al.
    Columbia University, NY USA.
    Hope, Thomas A.
    Stanford University, CA 94305 USA.
    Kari, Fabian A.
    University of Freiburg, Germany.
    Escobar Kvitting, John-Peder
    Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine.
    Liang, David H.
    Stanford University, CA 94305 USA.
    Herfkens, Robert J.
    Stanford University, CA 94305 USA.
    Craig Miller, D.
    Stanford University, CA 94305 USA.
    Greater asymmetric wall shear stress in Sievers type 1/LR compared with 0/LAT bicuspid aortic valves after valve-sparing aortic root replacement2015In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 150, no 1, p. 59-68Article in journal (Refereed)
    Abstract [en]

    Objective: To evaluate the role of commissure orientation on downstream blood flow patterns and ascending aortic wall shear stress (WSS) in patients with bicuspid aortic valves (BAV) after valve-sparing aortic root replacement (V-SARR). Methods: Nineteen BAV patients after V-SARR (9 Sievers type 1/LR [type 1 valve with fusion of the left and right cusps] and 10 Sievers type 0/LAT ["naturally perfect; type 0 valve without the presence of a raphe, and with the 2 commissures oriented right-anterior-to-left-posterior]) were imaged using time-resolved 3-D phase contrast magnetic resonance imaging. A control group of 5 unoperated tricuspid aortic valve patients were used for comparison purposes. Wall shear stress and eccentricity of flow normalized to aortic diameter were measured in planes placed perpendicular to the axis of the ascending aorta at the level of the sinotubular junction (proximal ascending), main pulmonary artery (mid-ascending), and origin of the brachiocephalic (distal ascending). Results: The ratio of WSS along the outer curvature to that along the inner curvature was greater in Sievers type 1/LR patients compared with Sievers type 0/LAT patients in the proximal (3.8 +/- 1.6 vs 2.1 +/- 0.9, P = .009) and mid-ascending aorta (4.5 +/- 2.4 vs 2.4 +/- 1.3, P = .027). Relative to control normal tricuspid patients, Sievers type 1/LR BAV patients had a higher WSS ratio in the mid-ascending aorta (4.5 +/- 2.4 vs 1.2 +/- 1.2, P = .007). Conversely, WSS in Sievers type 0/LAT patients was not different than in normal tricuspid patients. Conclusions: After V-SARR, BAV cusp morphology has a major impact on the pattern of blood flow and WSS in the ascending aorta.

  • 11.
    Svedjeholm, Rolf
    et al.
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Vanhanen, Ingemar
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Håkansson, Erik
    Linköping University, Department of Medicine and Care, Thoracic Surgery. Linköping University, Faculty of Health Sciences.
    Joachimsson, P. O.
    Department of Anesthesiology, Akademiska Hospital, Uppsala, Sweden.
    Jorfeldt, Lennart
    Department of Thoracic Physiology, Karolinska Hospital, Stockholm.
    Nilsson, Lennart
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Metabolic and hemodynamic effects of intravenous glutamate infusion early after coronary operations1996In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 112, no 6, p. 1468-1477Article in journal (Refereed)
    Abstract [en]

    Amino acids, particularly glutamate, have been proposed to play an important role in the recovery of cardiac oxidative metabolism after ischemia. In this investigation, the metabolic and hemodynamic effects of glutamate infusion after coronary operations were studied. From 220 to 240 ml 0.1 mol/L l-glutamic acid solution was infused in 10 patients during 1 hour starting 2 hours after operation. A control group of 10 patients received an infusion of 240 ml saline solution. During glutamate infusion, there were significant increases in the uptake of glutamate (from 0.7 ± 0.2 μmol/min in the basal state to a peak of 5.7 ± 1.2 μmol/min at 20 minutes) and lactate (from 4.9 ± 2.0 μmol/min in the basal state to 14.1 ± 4.4 μmol/min at 60 minutes; p < 0.01), whereas the uptake and release of other substrates remained essentially unaffected. Arterial glutamate levels (in whole blood) increased from 103 ± 10 μmol/L to 394 ± 20 μmol/L at 60 minutes. Thirty minutes after discontinuation of the glutamate infusion, arterial levels had decreased to 129 ± 17 μmol/L. The markedly improved utilization of lactate and the unchanged release of alanine together suggest that the oxidative metabolism of the heart was stimulated by glutamate. The metabolic changes were associated with improved myocardial performance. Left ventricular stroke work index increased from 26.8 ± 2.1 gm · beat-1· m-2body surface area to 31.3 ± 3.1 gm · beat-1· m-2body surface area during glutamate infusion. Metabolic support with amino acids may provide a means to improve recovery of metabolic and hemodynamic function of the heart early after cardiac operations.

  • 12.
    Vidlund, Marten
    et al.
    University of Örebro, Sweden .
    Håkansson, Erik
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Friberg, Orjan
    University of Örebro, Sweden .
    Juhl-Andersen, Soren
    Cardiothorac Anesthesia Blekinge Hospital, Sweden .
    Holm, Jonas
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    Vánky, Farkas
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Sunnermalm, Lena
    University of Örebro, Sweden .
    Borg, Jan-Olov
    Cardiothorac Anesthesia Blekinge Hospital, Sweden .
    Sharma, Rajiv
    Cardiothorac Anesthesia Blekinge Hospital, Sweden .
    Svedjeholm, Rolf
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    GLUTAMICS-a randomized clinical trial on glutamate infusion in 861 patients undergoing surgery for acute coronary syndrome2012In: Journal of Thoracic and Cardiovascular Surgery, ISSN 0022-5223, E-ISSN 1097-685X, Vol. 144, no 4, p. 922-Article in journal (Refereed)
    Abstract [en]

    Objective: Glutamate has been claimed to protect the heart from ischemia and to facilitate metabolic and hemodynamic recovery after ischemia. The GLUTAmate for Metabolic Intervention in Coronary Surgery trial investigated whether an intravenous glutamate infusion given in association with surgery for acute coronary syndrome could reduce mortality and prevent or mitigate myocardial injury and postoperative heart failure. less thanbrgreater than less thanbrgreater thanMethods: In the present prospective, triple-center, double-blind study, 861 patients undergoing surgery for acute coronary syndrome were randomly assigned to an intravenous infusion of glutamate (n=428) or saline (n=433) perioperatively. less thanbrgreater than less thanbrgreater thanResults: The incidence of the primary endpoint-a composite of 30-day mortality, perioperative myocardial infarction, and left ventricular heart failure at weaning from cardiopulmonary bypass-was 7.3% versus 5.8% (P=.41) in the glutamate and control groups, respectively. Patients with left ventricular failure at weaning from cardiopulmonary bypass had a shorter median intensive care unit stay (25 vs 92 hours; P=.02) if they were treated with glutamate. In patients with unstable angina (Canadian Cardiovascular Society class IV) undergoing isolated coronary artery bypass grafting (n=458), the incidence of severe circulatory failure according to the prespecified criteria was significantly lower in the glutamate group (1.3% vs 6.9%; P=.004). On multivariate analysis, glutamate infusion was associated with a reduced risk of developing severe circulatory failure (odds ratio, 0.17; 95% confidence interval, 0.04-0.72; P=.02). A relative risk reduction exceeding 50% for developing severe circulatory failure was seen in most risk groups undergoing isolated coronary artery bypass grafting, with those with diabetes a notable exception. less thanbrgreater than less thanbrgreater thanConclusions: The primary endpoint did not differ significantly between the groups. The secondary outcomes and post hoc analyses warrant additional studies with regard to the potential beneficial effect of glutamate on postischemic myocardial recovery.

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