Utilization of Implantable Defibrillators in the Octogenarian Population

Abstract

We evaluated the use of implantable defibrillators (ICDs) in the octogenarian population to analyze the complications associated with ICD implantation; the incidence of appropriate and inappropriate discharges; as well as survival following ICD implantation. We retrospectively evaluated the utilization of ICDs implanted and followed at our institution from 1998 to 2004 in the octogenarian population with systolic dysfunction. A control group was comprised of similar patients under the age of 80. Patients with preserved ventricular function were excluded. Two hundred twenty-six patients with systolic dysfunction were evaluated following ICD implantation. There were 51 patients over 80 years of age (mean age: 84 ± 4). A control group of 175 patients less than age 80 (mean age: 66 ± 10) was utilized for comparison. The baseline characteristics, including ejection fraction (25 ± 7%), presence of coronary disease (90%), as well as the incidence of symptomatic arrhythmias (33%) were similar in both groups. The octogenarian population did have a higher percentage of women (31% v. 18% (p = 0.04)). The long-term device related complication rate in the older age group was low (1.9%) and did not differ between groups. Thirty-two percent of the octogenarian group received appropriate ICD therapy over a mean follow-up period of 15 ± 16 months. The older group had fewer inappropriate discharges (6.8% v. 12.6%; p = NS) in comparison to the younger patient group. Although 78.4% of the octogenarian group survived during the follow-up period, there was a significant decrease in survival in this group as evaluated by the Kaplan Meier method (p=0.0003). In multivariate analysis, the only significant predictor of survival was age less than 80. The octogenarian population can safely be treated with ICD therapy and in appropriately selected patients; they can be expected to have a high rate of therapeutic ICD utilization. Patients should be carefully selected for ICD implantation as mortality is higher in the octogenarian population and co-morbid conditions may limit the potential survival benefit offered by the ICD.