Prognostic value of mitral valve apparatus morphological parameters in patients with dilated cardiomyopathy

Background Mitral annulus (MA) morphology is abnormal in patients with dilated cardiomyopathy (DCM). Real-time four-dimensional transthoracic echocardiographic (RT4D TTE) imaging techniques provide essential information in different clinical settings, including DCM. The study aimed to find how MA parameters correlated with survival and heart failure (HF) rehospitalization during two years of follow-up. Methods The study included 82 DCM patients (46.32% of ischemic etiology) admitted with decompensation of heart failure and with left ventricular ejection fraction (LVEF) below 40%. The patients were evaluated by clinical examination, 12-lead electrocardiography, and biochemical tests performed at admission and during the hospital stay. All patients underwent a comprehensive TTE evaluation to determine cardiac morphology and function according to the current guidelines. The images were acquired in all cases before discharge, after careful compensation for hydric retention, using commercial ultrasound systems for image acquisition. The analysis was performed offline by EchoPAC version 204 software using Four-Dimensional Automated Mitral Valve Quantification (4D Auto MVQ) software. The study evaluated annulus area (AA)3D, annulus perimeter (AP), anteroposterior diameter (A-Pd), posteromedial-anterolateral diameter (PM-ALd), commissural diameter (CD), inter-trigonal distance (Itd), annular height (AH), non-planar angle (NPa), tenting height (TH), tenting area (TA), and tenting volume (TV). Results 1. 10 patients in the ischemic group (31.25%), and 15 (34.09 %) patients in the nonischemic group, p=0.78, died; 17 (44.77%) patients in the ischemic group and 22 (50%) in the nonischemic group, p=0.63, were readmitted with signs and symptoms of HF during follow-up. 2. Using univariate logistic regression, we found A-Pd, AA, AP, CD, Itd, PM-ALd, and TV as predictors of mortality and HF rehospitalization. 3. Multivariate analysis identified Itd as a predictor of mortality with a value of > 3.6 cm (80% sensitivity and 60% specificity, AUC 0.766, p<0.001) and CD as a predictor of HF readmission with a value >4.7cm (79.5 sensitivity and 53.5 specificity, AUC 0.706, p<0.001) during follow-up. Conclusion 1. In patients with DCM and advanced stages of HF, both rehospitalization and mortality are higher in the nonischemic vs ischemic group, but without a significant difference. 2. MA parameters: A-P diameter, AA, AP, CD, Itd, PM-AL diameter, and TV correlated with mortality and rehospitalization. 3. Multivariate analysis identified Itd as a predictor of mortality, and CD as a predictor of HF rehospitalization during a two-year follow-up.