Association between red blood cell distribution width and response to cardiac resynchronization therapy.

PURPOSE: Red blood cell distribution width (RDW) predicts adverse outcomes in patients with heart failure. We aimed to investigate the prognostic value of RDW on response to cardiac resynchronization therapy (CRT). METHODS: Sixty-six consecutive patients (mean age, 57 ± 13 years; 42 men) undergoing CRT were included in the study. Hematological parameters and echocardiographic parameters were measured before and 6 months after CRT. An echocardiographic response to CRT was defined as a ≥15 % relative increase in left ventricular ejection fraction after 6 months. RESULTS: After 6 months of CRT, 47 (71 %) patients were responders. High baseline RDW levels were found in 11 (23 %) and 10 (52 %) patients in responders and non-responders, respectively (p < 0.05). In non-responders, RDW at 6 months was significantly high compared to baseline RDW (17.1 ± 2 vs. 19 ± 2.9) (p < 0.001). There was not any significant change in RDW after CRT in responders (16 ± 1.6 vs. 15.5 ± 1.4) (p > 0.05). In multivariate analysis, significant associates of response to CRT were evaluated adjusting for QRS width, QRS morphology, age, New York Heart Association functional class, hemoglobulin, and RDW level. Baseline RDW level was the only predictor of response to CRT (odds ratio, 1.435; 95 % confidence interval, 1.059-1.945, p = 0.020). CONCLUSIONS: Our data suggest that patients with elevated RDW at baseline are associated with poor response to CRT. Therefore, RDW at baseline could help to identify patients with response to CRT.