Abstract 15208: Long-Term Outcome of Cardiac Resynchronization Therapy in the Elderly.
Background: Most clinical trials of cardiac resynchronization therapy (CRT) exclude elderly patients. Long-term outcome of elderly patients undergoing CRT has not yet been fully studied.
Purpose: To evaluate long-term clinical outcome of elderly patients who underwent CRT.
Methods: CUBIC study is a multi-center registry of Japanese patients with heart failure undergoing CRT. A total of 643 patients (216 elderly patients: age ≥ 75 years; 427 younger patients: age < 75 years) from 11 centers were enrolled during 2004–2008.
Results: A mean follow-up period was 663 days. Compared with the younger patients, the elderly patients were more likely to have wide QRS width (156 msec. vs. 147 msec., p=0.005), high BNP values (810 pg/ml vs. 657 pg/ml, p=0.05), high left ventricular (LV) ejection fraction (29% vs. 27%, p=0.007) and small LV end-diastolic dimension (LVEDD) (60 mm vs. 64mm, p < 0.0001). The prevalence of ischemic etiology (the elderly=35% vs. the younger=30%), chronic kidney disease (CKD) (30% vs. 27%), chronic atrial fibrillation or flutter (26% vs. 20%), diabetes mellitus (35% vs. 32%) and severe mitral regurgitation (MR) (16% vs. 13%) were similar between the 2 groups. The crude survival rates were comparable between the elderly and the younger (at 2 years, the elderly: 81.3% vs. the younger: 81.1%, log rank p=0.81). There was also no significant difference in the rate of freedom from hospitalization for heart failure between the 2 groups (at 2 years, the elderly: 69.3% vs. the younger: 71.7%, log rank p=0.95). Responder rate defined as an improvement (≥ 1 score) of New York Heart Association class after 6 months was similar between the 2 groups (the elderly: 67.0% vs. the younger: 63.4%, p=0.39). Reverse LV remodeling defined as LV end-systolic volume reduction ≥ 15% assessed by echocardiography after 6 months was more often seen in the elderly than in the younger (64.3% vs. 53.6%, p=0.02). After adjustment for severity of MR, ischemic etiology, LVEDD, CKD, chronic atrial fibrillation or flutter and diabetes, the elderly patients was not associated with an increased risk of any cause death (hazard ratio 1.10, 95% confidence interval 0.75 to 1.61, p=0.61).
Conclusions: Long-term clinical outcome of CRT was comparably favorable in elderly patients to younger patients.
- © 2010 by American Heart Association, Inc.