Analysis of Implantable Defibrillator Longevity Under Clinical Circumstances: Implications for Device Selection

Methods: Indications for replacement were classified as a normal end-of-service (EOS), premature EOS, system malfunction, infection and device advisory, or recall actions. From the premature and normal EOS group, longevity from single-chamber (SC), dual-chamber (DC), and cardiac resynchronization therapy defibrillator (CRT-D), rate-responsive (RR) settings, high output (HO) stimulation, and indication for ICD therapy was compared. Differences between brands were compared as well. Results: In a total of 854 patients, 203 ICD replacements (165 patients) were recorded. Premature and normal EOS replacements consisted of 32 SC, 98 DC and 24 CRT-D systems. Longevity was significantly longer in SC systems compared to DC and CRT-D systems (54 +/- 19 vs. 40 +/- 17 and 42 +/- 15 months; P = 0.008). Longevity between non-RR (n = 143) and RR (n = 11) settings was not significantly different (43 +/- 18 vs. 45 +/- 13 months) as it also was not for HO versus non-HO stimulation (43 +/- 19 vs. 46 +/- 17 months). Longevity of ICDs was not significantly different between primary and secondary prevention (42 +/- 19 vs. 44 +/- 18 months). The average longevity on account of a device-based EOS message was 43 +/- 18 months. Average longevity for Biotronik (BIO, n = 72) was 33 +/- 10 months, for ELA Medical (ELA, n = 12) 44 +/- 17 months, for Guidant (GDT, n = 36) 49 +/- 12 months, for Medtronic (MDT, n = 29) 62 +/- 22 months, and for St. Jude Medical (SJM, n = 5) 31 +/- 9 months (P < 0.001). Conclusion: SC ICD generators had a longer service time compared to DC and CRT-D systems. No influence of indication for ICD therapy and HO stimulation on generator longevity was observed in this study. MDT ICDs had the longest service time. (PACE 2009; 1276-1285)