Comparison of the usefulness of cardiac resynchronization therapy in three age-groups (<65, 65-74 and ≥75 Years) (from the InSync/InSync ICD Italian Registry)

Abstract

Chronic heart failure is one of the most important geriatric syndromes, associated with disability, increased hospital admissions, and high mortality. The aim of this study was to evaluate the existence of age-related differences in clinical effectiveness and outcomes of cardiac resynchronization therapy (CRT), alone or in combination with an implantable cardioverter-defibrillator (CRT-D), in a large, real-world registry. A total of 1,787 patients admitted for CRT or CRT-D to the 117 centers participating in the InSync/InSync ICD Italian Registry from 1999 to 2005 were evaluated. Patients were divided into 3 age groups: <65 years (n = 571), 65 to 74 years (n = 740), and ≥75 years (n = 476). The left ventricular ejection fraction did not differ in the 3 groups (26 ± 8% vs 26 ± 7% vs 27 ± 8%, p = 0.123). Atrial fibrillation prevalence demonstrated an age-related increase. The use of recommended medical therapy for chronic heart failure decreased with age, as well as CRT-D implantation (p <0.001). The percentage of echocardiographic responders to CRT was similar in the 3 groups, and New York Heart Association class significantly improved independent of age. During the follow-up period (19 ± 13 months), all-cause mortality was higher in patients aged ≥75 years than in those aged <65 years (p = 0.005). In the whole population, mortality was associated with the nonresponder condition, the presence of atrial fibrillation and the lack of prescription of recommended medical therapy. In conclusion, CRT improved left ventricular performance and functional capacity independent of age. The proportion of the responder condition to CRT was the same in all groups. Pharmacologic undertreatment is an important issue in a "real-world" geriatric population.