Clinical and echocardiographic predictors of nonresponse to cardiac resynchronization therapy

Background Lack of response to cardiac resynchronization therapy (CRT) ranges between 30% to 40% of heart failure (HF) patients. The present study aimed to evaluate the clinical and echocardiographic determinants of nonresponse to CRT.Methods A total of 581 patients (66.4 +/- 10.0 years, 77.9% male) with advanced HF scheduled for CRT implantation were included. Clinical and echocardiographic evaluations were performed at baseline and 6 months of follow-up. Nonresponse was defined as no improvement in the New York Heart Association functional class, death from worsening HF or heart transplantation, and < 15% reduction in left ventricular (LV) end-systolic volume.Results At 6 months of follow-up, 254 patients (44%) did not respond to CRT. The nonresponders were more frequently male (81.9% vs 74.3%, P = .030) and had ischemic cardiomyopathy (69.7% vs 53.2%, P < .001), shorter QRS duration (150.6 +/- 29.9 milliseconds vs 156.0 +/- 32.5 milliseconds, P = .041), worse New York Heart Associat...