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Abstract: Purpose: To assess regional myocardial microvascular dysfunction differences in hypertrophic cardiomyopathy (HCM) patients with or without left ventricular outflow tract obstruction using 3.0-T cardiac magnetic resonance (CMR) first-pass perfusion imaging. Materials and methods: Forty-two HCM patients, including 25 HCM patients with left ventricular outflow tract obstruction (HOCM), 17 HCM patients without left ventricular outflow tract obstruction (NOHCM), and 14 healthy subjects underwent CMR. The left ventricular (LV) function, left ventricular end-diastolic wall thickness (EDTH), and diameter of left ventricular outflow tract (LVOT) were measured and calculated. Based on the signal–time curve of the first-pass myocardium perfusion imaging, perfusion parameters including upslope, time to peak, and peak intensity, were assessed and compared by using one-way analysis of variance and independent t tests. Results: On the first-pass perfusion imaging, lower upslope and peak intensity and longer time to peak were found in HCM patients compared with normal subjects (all p <0.05). In contrast to the NOHCM group, the average time to peak of the HOCM group was increased (13.30±4.82s vs 16.28±4.90s, p <0.05), but first-pass perfusion upslope was reduced (4.96±2.55 vs 2.58±0.77, p <0.05). According to the bull's-eye model, the HOCM group's average thickness of basal segments was thicker than the NOHCM group, especially the anteroseptal, inferolateral, and anterior wall values, with a corresponding lower first-pass perfusion upslope than the NOHCM group (all p <0.05). A significant correlation was observed between first-pass perfusion upslope and LV EDTH (r =−0.551, p <0.001) and LVOT diameter (r =0.472, p <0.001). Conclusions: The regional myocardial microvascular dysfunction differences in hypertrophic cardiomyopathy (HCM) patients with or without left ventricular outflow tract obstruction can be detected with first-pass perfusion CMR imaging. [Copyright &y& Elsevier]

Purpose: The aim of this study was to clarify the feasibility of myocardial strain using cardiovascular magnetic resonance (CMR) for the evaluation of left ventricular (LV) deformation in patients with Ebstein's anomaly (EA).Materials and Methods: We recruited 32 patients with EA and 30 controls for CMR examination and measured LV function, dimension and tissue tracking parameters (the global and regional radial, circumferential and longitudinal peak strain), together with the right ventricle (RV) dimension. LV strain parameters were compared among the controls, patients with preserved LV ejection fraction (LVEF; ≥55%), and patients with reduced LVEF (<55%). Pearson's correlation was used to evaluate relationships between tissue tracking parameters with the RVEDD/LVEDD index and LVEF. An ROC analysis was also performed to determine whether the cut-off values for PS could be used to differentiate LV dysfunction between patients with EA and controls. The intraclass correlation coefficient (ICC) was used to assess the inter- and intra-observer variability.Results: The global strain parameters all decreased significantly in the EA group compared with the control group (all P<0.05). Furthermore, the global radial and circumferential peak strain (PS) were obviously even lower in the reduced LVEF group than the strain measured in preserved LVEF groups (28.64% vs. 37.39%, p<0.05; and -8.20% vs. -17.89%; p<0.05; respectively). The regional strain abnormalities in EA patients were mainly involved in basal and middle segments. The results also demonstrated a significant correlation between the ratio of the RV end-diastolic dimension to the LV end-diastolic dimension (RVEDD/LVEDD index) with the global circumferential PS (r=0.508) and the longitudinal PS (r=0.474), as well as a good correlation between radial PS and LVEF (r=0.465). The ICCs for intra- and inter-observer variability were 0.797-0.904 and 0.701-0.896.Conclusions: LV strain serves an earlier and more comprehensive measurement of LV dysfunction than LVEF in EA, which could potentially be included as a supplementary diagnostic procedure in the evaluation of EA. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to assess the correlations of functional and dimensional parameters with the severity of tricuspid regurgitation in patients with Ebstein's anomaly (EA) by using cardiac magnetic resonance (CMR) imaging. Materials and Methods: Thirty-three patients with EA without previous cardiac surgery and 25 normal individuals were recruited and underwent both cardiac MR imaging and preoperative transthoracic echocardiography. The left ventricular (LV) functional parameters and dimensions of the right ventricle (RV) and LV were measured using 3.0-T cardiac MR imaging. Tricuspid regurgitation severity grading was estimated by echocardiography. The functional and dimensional parameters were compared between EA patients and controls using independent sample t-tests. Spearman's rank correlation was used to determine the correlations between the functional and dimensional parameters and tricuspid regurgitation. Receiver operating characteristic (ROC) analysis was used to predict tricuspid regurgitation severity using individual functional and dimensional parameters. Results: Statistical analysis revealed significant differences in the functional and dimensional parameters between EA patients and controls. Within the EA group, tricuspid valve regurgitation negatively correlated well with the left ventricular ejection fraction (LVEF) (r=-0.558, p=0.001). The ratio of the right ventricular (functional right ventricle) end-diastolic dimension to the left ventricle end-diastolic dimension (RVEDD/LVEDD) in EA patients also correlated well with the severity of tricuspid valve regurgitation (r=0.492, p=0.004). Moreover, ROC analysis revealed that high sensitivity and specificity were obtained for predicting the severity of tricuspid valve regurgitation with LVEF (78.3%, 90.0%) and RVEDD/LVEDD (78.3%, 94.3%). Conclusion: In EA patients, the left and right ventricular functional and dimensional parameters from MRI correlated well with tricuspid regurgitation, which helped predict the severity of EA. [ABSTRACT FROM AUTHOR]