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Diastolic Strain Rate (diastolic + strain_rate)
Selected AbstractsStrain-Encoded Cardiac Magnetic Resonance for the Evaluation of Chronic Allograft Vasculopathy in Transplant RecipientsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 11 2009G. Korosoglou The aim of our study was to investigate the ability of Strain-Encoded magnetic resonance imaging (MRI) to detect cardiac allograft vasculopathy (CAV) in heart transplantation (HTx)-recipients. In consecutive subjects (n = 69), who underwent cardiac catheterization, MRI was performed for quantification of myocardial strain and perfusion reserve. Based on angiographic findings subjects were classified: group A including patients with normal vessels; group B, patients with stenosis <50%; and group C, patients with severe CAV (stenosis , 50%). Significant correlations were observed between myocardial perfusion reserve with peak systolic strain (r =,0.53, p < 0.001) and with mean diastolic strain rate (r = 0.82, p < 0.001). Peak systolic strain and strain rate were significantly reduced only in group C, while mean diastolic strain rate and myocardial perfusion reserve were already reduced in group B and A. Myocardial perfusion reserve and mean diastolic strain rate had higher accuracy for the detection of CAV (AUC = 0.95, 95% CI = 0.87,0.99 and AUC = 0.93, 95% CI = 0.84,0.98, respectively) and followed peak systolic strain and strain rate (AUC = 0.80, 95% CI = 0.69,0.89 and AUC = 0.78, 95% CI = 0.67,0.87, respectively). Besides the quantification of myocardial perfusion, the estimation of the diastolic strain rate is a useful parameter for CAV assessment. In combination with the clinical evaluation, these parameters may be effective tools for the routine surveillance of HTx-recipients. [source] Regional Diastolic and Systolic Function by Strain Rate Imaging for the Detection of Intramural Viability during Dobutamine Stress Echocardiography in a Porcine Model of Myocardial InfarctionECHOCARDIOGRAPHY, Issue 5 2010Carsten Schneider M.D. The aim of this study was to evaluate diastolic and systolic strain rate measurements for differentiation of transmural/nontransmural infarction during dobutamine stress echocardiography (DSE). An ameroid constrictor was placed around the circumflex artery in 23 pigs inducing chronic vessel occlusion. Five pigs without constrictor served as controls. During high-dose DSE systolic strain rates (SRsys), systolic and postsystolic strain values (,sys, ,ps) and early and late diastolic strain rates (SRE and SRA) were determined. At week 6, animals were evaluated regarding myocardial fibrosis. Histology revealed nontransmural in 14 and transmural infarction in 9 animals. In controls, dobutamine induced a linear increase of SRsys to 12.3 ± 0.4 s,1 at 40 ,g/kg per minute (P = 0.001) and a linear decrease of SRE to ,6.6 ± 0.3 s,1 (P = 0.001). In the nontransmural group, SRsys, ,sys, ,ps at rest, and during DSE were higher and SRE was lower than in the transmural infarction group (P = 0.01). Best predictors for viability were SRsys (ROC 0.96, P = 0.0003), SRE at 10 ,g/kg per minute dobutamine stimulation (ROC 0.94, P = 0.001) and positive SR values during isovolumetric relaxation at 40 ,g/kg per minute dobutamine (ROC 0.86, P = 0.004). The extension of fibrosis correlated with SRsys at rest, ,sys at rest, and SRE at rest (P < 0.001). For the detection of viability similar diagnostic accuracies of SRE and SRsys were seen (sensitivity 93%/93%, specificity 96%/94%, respectively). Diastolic SR analysis seems to be equipotent for the identification of viable myocardium in comparison to systolic SR parameters and allows the differentiation of nontransmural from transmural myocardial infarction with high diagnostic accuracy. (Echocardiography 2010;27:552-562) [source] Restrictive Right Ventricular Physiology and Right Ventricular Fibrosis as Assessed by Cardiac Magnetic Resonance and Exercise Capacity After Biventricular Repair of Pulmonary Atresia and Intact Ventricular SeptumCLINICAL CARDIOLOGY, Issue 2 2010Xue-Cun Liang MD Background The hypertrophic myocardium, myocardial fiber disarray, and endocardial fibroelastosis in pulmonary atresia and intact ventricular septum (PAIVS) may provide anatomic substrates for restrictive filling of the right ventricle. Hypothesis Restrictive right ventricle (RV) physiology is related to RV fibrosis and exercise capacity in patients after biventricular repair of PAIVS. Methods A total of 27 patients, age 16.5 ± 5.6 years, were recruited after biventricular repair of PAIVS. Restrictive RV physiology was defined by the presence of antegrade diastolic pulmonary flow and RV fibrosis assessed by late gadolinium enhancement (LGE) cardiac magnetic resonance. Their RV function was compared with that of 27 healthy controls and related to RV LGE score and exercise capacity. Results Compared with controls, PAIVS patients had lower tricuspid annular systolic and early diastolic velocities, RV global longitudinal systolic strain, systolic strain rate, and early and late diastolic strain rates (all P < 0.05). A total of 22 (81%, 95% confidence interval: 62%,94%) PAIVS patients demonstrated restrictive RV physiology. Compared to those without restrictive RV physiology (n = 5), these 22 patients had lower RV global systolic strain, lower RV systolic and early diastolic strain rates, higher RV LGE score, and a greater percent of predicted maximum oxygen consumption (all P < 0.05). Conclusion Restrictive RV physiology reflects RV diastolic dysfunction and is associated with more severe RV fibrosis but better exercise capacity in patients after biventricular repair of PAIVS. Copyright © 2010 Wiley Periodicals, Inc. [source] | ||||||||||