Abstract 17225: Early Subjective Improvement of Exercise Capacity is an Indpendent Predictor of Long Term Survival in Cardiac Resynchronization Therapy Patients
Introduction: Cardiac Resynchronization Therapy (CRT) is an effective treatment for selected patients with heart failure. However there is a significant minority who do not seem to benefit from improved heart failure symptoms and reverse remodelling after CRT implant. We sought to assess the effect on long term survival of baseline clinical data in combination with the variable “subjective improvement of physical exercise capacity” 1-2 months post-implant.
Methods: Data from 504 consecutive patients implanted with CRT-P or CRT-D (2006-2012) at a large Swedish tertiary care centre were collected from medical records. Endpoint was death at follow-up. Predictors of mortality were calculated using logistic regressions analysis, adjusting for follow-up time. A separate comparison was made between CRT-P and CRT-D groups.
Results: The patients were followed for a mean of 38 months and the population was similar in baseline characteristics compared to the major controlled trials (LVEF25±6%, QRSduration 165±27ms, Age 70±10years, 55% ischemic cardiomyopathy, 58% NYHA III-IV, 83%male, history of atrial fibrillation 45%, 56% CRT-D and 44% CRT-P). Univariate predictors (adjusted for follow-up time) were; CRT-D (OR: 0,534, P:1,012, CI:0,327-0,870), older age (OR 1.064, P<0,001, CI 1.035-1.094), ischaemic cardiomyopathy (OR 2.417, P=0.002, CI 1.381-4.231), and subjective improvement (OR 0.389, P=0.004, CI 0.206-0.735). The only independent predictors of mortality at follow-up were older age and subjective improvement; OR 1.069 per year (95% CI 1.018-1.121, P=0.007) and 0.312 (95% CI, 0.122-0.822, P=0.016) respectively.
Conclusions: Real-life patient characteristics compare well with those in the published prospective trials. Subjective improvement in the short term is a strong predictor of survival in the long term. This finding may indicate that a more active follow-up is necessary for optimizing therapy in patients without spontaneous improvement after one month. Adding a defibrillator was not an independent predictor of improved survival in this cohort, even though there was a trend for added benefit.
- © 2013 by American Heart Association, Inc.