Comorbidity significantly affects clinical outcome after cardiac resynchronization therapy irrespectively of ventricular remodeling

Abstract

Background: The influence of comorbidity on ventricular remodelling, functional status and clinical outcome after cardiac resynchronization therapy (CRT) is insufficiently elucidated. Methods: The influence of different comorbid conditions on left ventricular remodelling, improvement in New York Heart Association (NYHA) functional class, hospitalizations for heart failure and all-cause mortality, was analysed in 172 consecutive patients (mean age 71 +/- 9 y), implanted from October 2008 to April 2011 in a single tertiary care hospital. During mean follow-up of 18 +/- 9 months, 21 patients died and 57 were admitted for heart failure. Left ventricular remodeling and improvement in NYHA functional class were independent from comorbidity burden. However, diabetes mellitus (hazard ratio [HR] 3.45, 95% confidence interval [CI] 1.24-9.65) and chronic kidney disease (HR 3.11, 95% CI 1.10-8.81) were predictors of all-cause mortality, and the presence of chronic obstructive pulmonary disease (HR 1.89, 95% Cl 1.02-3.53) was independently associated with heart failure admissions. Importantly, those 3 comorbid conditions had an additive negative impact on survival and heart failure admissions, even in patients with reverse left ventricular remodeling. Conclusions: Reverse ventricular remodeling and improvement in functional status after CRT implantation are independent from comorbidity burden. However, comorbid conditions remain important predictors of all-cause mortality and heart failure admissions.