RESUMO
PURPOSE: This study aimed to analyze left ventricular (LV) remodeling in patients with LV dilation using three-dimensional (3D) echocardiography, and to compare geometry and systolic function between patients with dilated cardiomyopathy (DCM) and with mitral regurgitation (MR) but similar LV dimension. METHODS: Cross-sectional study of 60 DCM and 60 MR patients with LV end diastolic diameter (LVEDD) > 35 mm/m2 , and of 60 healthy control volunteers. RESULTS: Despite a similar LVEDD, DCM patients showed a significantly higher 3D sphericity index (3D-SI) than MR patients, whereas 3D ejection fraction (3D-EF) was significantly lower (P < .01). There was a linear relationship between 3D-EF and 3D-SI in both DCM and MR patients (r = -0. 745 and r = -0. 642, respectively; both P < .001). Receiver operating characteristic (ROC) curves showed that 3D-SI had could better discriminate between DCM and MR (sensitivity 90%; specificity 73%; AUC 0.852, P < .01) than other variables. The area under the ROC curve of 3D-SI was significantly larger than that of 3D-EF for detecting heart failure in both patients with DCM and MR. CONCLUSIONS: LV geometry appears to be more spherical and associated with worse systolic function in DCM than in MR patients, in spite of similar LV dimensions. Systolic function correlated significantly with 3D-SI, which provided a better description of LV remodeling and could be a stronger indicator of heart failure in patients with LV dilation.