NPPB and miotic rate: With increase in MR severity, left ventricular end-diastolic dimension (LEVDD), left ventricular end-systolic diameter; LA size (LVESD), left atrial size (LA size), E/A, and N-terminal pro-brain natriuretic peptide (NT-proBNP) gradually increased (P < 0.001), whereas left ventricular ejection fraction (LVEF) gradually decreased (P < 0.001).