Implantable cardioverter-defibrillator longevity under clinical circumstances: an analysis according to device type, generation, and manufacturer.

BACKGROUND: One of the major drawbacks of implantable cardioverter-defibrillator (ICD) treatment is the limited device service life. Thus far, data concerning ICD longevity under clinical circumstances are scarce. In this study, the ICD service life was assessed in a large cohort of ICD recipients.
OBJECTIVE: To assess the battery longevity of ICDs under clinical circumstances.
METHODS: All patients receiving an ICD in the Leiden University Medical Center were included in the analysis. During prospectively recorded follow-up visits, reasons for ICD replacement were assessed and categorized as battery depletion and non-battery depletion. Device longevity and battery longevity were calculated. The impact of device type, generation, manufacturer, the percentage of pacing, the pacing output, and the number of shocks on the battery longevity was assessed.
RESULTS: Since 1996, 4673 ICDs were implanted, of which 1479 ICDs (33%) were replaced. Mean device longevity was 5.0 ± 0.1 years. A total of 1072 (72%) ICDs were replaced because of battery depletion. Mean battery longevity of an ICD was 5.5 ± 0.1 years. When divided into different types, mean battery longevity was 5.5 ± 0.2 years for single-chamber ICDs, 5.8 ± 0.1 for dual-chamber ICDs, and 4.7 ± 0.1 years for cardiac resynchronization therapy-defibrillators (P <.001). Devices implanted after 2002 had a significantly better battery longevity as compared with devices implanted before 2002 (5.6 ± 0.1 years vs 4.9 ± 0.2 years; P <.001). In addition, large differences in battery longevity between manufacturers were noted (overall log-rank test, P <.001).
CONCLUSIONS: The majority of ICDs were replaced because of battery depletion. Large differences in longevity exist between different ICD types and manufacturers. Modern ICD generations demonstrated improved longevity.