Long-term outcomes in nonprogressors to cardiac resynchronization therapy

Background: Among patients with heart failure undergoing cardiac resynchronization therapy (CRT), patients with a minimal change in left ventricular ejection fraction (LVEF) have recently been defined as “nonprogressors” rather than as “nonresponders.” Little is known regarding long-term outcomes of nonprogressors. Objective: We sought to evaluate outcomes in patients undergoing CRT on the basis of echocardiographically determined response status. Methods: We reviewed the medical charts of patients with an LVEF of ≤35% and a QRS duration of ≥120 ms undergoing CRT at the Cleveland Clinic, Johns Hopkins Hospital, and Johns Hopkins Bayview Medical Center between 2003 and 2014. Response to CRT was defined on the basis of LVEF change as follows: super-responders ≥20%, responders 6%–19%, nonprogressors 0%–5%, and progressors <0%. Survival free of left ventricular assist device (LVAD) implantation and heart transplantation was compared on the basis of response classification. Results: A total of 1058 patients were included and had a mean follow-up 8.7 ± 5.4 years, over which time there were 606 end points (37 LVAD implants, 32 heart transplants, and 537 deaths). Survival free of LVAD and heart transplant differed significantly between response groups after CRT both in the mid-term (4 years) and in the long-term (8.7 ± 5.4 years), with super-responders achieving the best outcomes and progressors the worst (P < .001). In multivariate analysis, nonprogressors had superior outcomes to progressors (P = .02) at 4 years of follow-up. Over the duration of follow-up (8.7 ± 5.4 years), there was no significant difference in survival between those 2 groups (P = .18). Conclusion: Nonprogressors to CRT have superior medium-term outcomes but similar long-term outcomes to progressors and inferior outcomes to responders and super-responders.