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 Association functional class (2.8 ± 0.6 vs 2.7 ± 0.6, P = .008) and shorter 6-minute walk distance (297.9 ± 110.7 m vs 331.8 ± 112.6 m, P = .001), larger left atrial volumes (44.9 ± 16.9 mL/m2vs 40.9 ± 17.6 mL/m2, P = .006), less baseline LV dyssynchrony (56.2 ± 41.3 milliseconds vs 69.1 ± 39.9 milliseconds, P < .001), and, more frequently, anterior LV lead position (12.4% vs 4.0%, P = .007). At multivariate analysis, only the ischemic etiology of HF (odds ratio [OR] 2.264, P = .005), shorter 6-minute walk distance at baseline (OR 0.998, P = .030), less baseline LV dyssynchrony (OR 0.989, P < .001), and anterior LV lead position (OR 3.713, P < .010) remained independent predictors of nonresponse to CRT. Conclusions: Ischemic etiology of HF, shorter baseline 6-minute walk distance, less baseline LV dyssynchrony, and anterior LV lead position are independent determinants of nonresponse to CRT.

doi.org/10.1016/j.ahj.2010.11.011, hdl.handle.net/1765/33504
American Heart Journal
Erasmus MC: University Medical Center Rotterdam

Shanks, M., Delgado, V., Ng, A., Auger, D., Mooyaart, E. A. Q., Bertini, M., Marsan, N. A., van Bommel, R., Holman, E., Poldermans, D., Schalij, M. J.& Bax, J. (2011). Clinical and echocardiographic predictors of nonresponse to cardiac resynchronization therapy. American Heart Journal, 161(3), 552–557.https://doi.org/10.1016/j.ahj.2010.11.011