Cited 21 times since 2011 (1.6 per year) source: EuropePMC American heart journal, Volume 161, Issue 3, 31 5 2011, Pages 552-557 Clinical and echocardiographic predictors of nonresponse to cardiac resynchronization therapy. Shanks M, Delgado V, Ng AC, Auger D, Mooyaart EA, Bertini M, Marsan NA, van Bommel RJ, Holman ER, Poldermans D, Schalij MJ, Bax JJ
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/m(2) vs 40.9 ± 17.6 mL/m(2), 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.
