Background: Cardiac resynchronization therapy (CRT) has been shown to reduce heart failure-related morbidity and mortality. However, approximately one in three patients do not respond to CRT. The aim of the current study was to determine the parameter(s) which predict reverse remodeling and clinical improvement after CRT.
Methods: A total of 54 patients (43 male, 11 female; mean age 61.9 ± 10.5 years) with heart failure and New York Heart Association (NYHA) class III-IV symptoms and in whom left ventricular ejection fraction (LVEF) was £ 35% and QRS duration was ≥ 120 ms, despite optimal medical therapy, were enrolled. An echocardiographic examination was performed before, and six months after, CRT. An echocardiographic response was defined as a reduction of end-systolic volume ≥ 10% after six months, and a clinical response was defined as a reduction ≥ 1 in the NYHA functional class score.
Results: An echocardiographic response was observed in 38 (70.4%) of the patients and a clinical response occurred in 41 (75.9%) of the patients. Of the dyssynchrony parameters, only the aortic pre-ejection interval (APEI) was observed to significantly predict the clinical response (p = 0.048) and echocardiographic response (p = 0.037). A 180.5 ms cut-off value for the APEI predicted the clinical response with a sensitivity of 92.3% and a specificity of 39%, and the echocardiographic response with a sensitivity of 93.0% and a specificity of 42%.
Conclusions: APEI derived from pulsed-wave Doppler, which is available in every echocardiography machine, is a simple and practical method that could be used to select patients for CRT.