Baseline QRS width and mitral regurgitation behavior after cardiac resynchronization therapy among patients with dilated cardiomyopathy

AbstractBackgroundThe effect of cardiac resynchronization therapy (CRT) on functional mitral regurgitation (FMR) is reflected on both clinical and echocardiographic response. We sought to assess the behavior of FMR and the response to CRT implantation in relation to the baseline width of the QRS complex among patients with dilated cardiomyopathy (DCM).Patients and methodsThis is a prospective observational case-control study, including forty patients with advanced DCM who had left bundle branch block (LBBB), QRS⩾130ms (group 1) and 10 patients with QRS