Recurrent Implantable Cardioverter-Defibrillator Replacement Is Associated with an Increasing Risk of Pocket-Related Complications

BACKGROUND: Despite beneficial effects of implantable cardioverter-defibrillator (ICD) therapy, limited service life results in replacement within the majority of patients. Data concerning the effect of replacement procedures on the occurrence of pocket-related adverse events are scarce. In this study, the requirement for pocket-related surgical re-interventions following ICD treatment and the effect of device replacement were evaluated. METHODS: From 1992 to 2008, 2,415 patients receiving an ICD at the Leiden University Medical Center were analyzed. Pocket-related complications requiring surgical re-intervention following ICD implantation or replacement were noted. Elective device replacement, lead failure, and device malfunction were not considered pocket-related complications. RESULTS: A total of 3,161 ICDs were included in the analysis. In total, 145 surgical re-interventions were required in 122 (3.9%) ICDs implanted in 114 (4.7%) unique patients. Three-year cumulative incidence for first surgical re-intervention in all ICDs was 4.7% (95% confidence interval CI 3.9-5.5%). Replacement ICDs exhibited a doubled requirement for surgical re-intervention (rate ratio 2.2, 95% CI 1.5-3.0). Compared to first implanted ICDs, the occurrence of surgical re-intervention in replacements was 2.5 (95% CI 1.6-3.7) times higher for infectious and 1.7 (95% CI 0.9-3.0) for noninfectious causes. Subdivision by the number of ICD replacements showed an increase in the annual risk for surgical re-intervention, ranging from 1.5% (95% CI 1.2-1.9%) for the first, to 8.1% (95% CI 1.7-18.3%) for the fourth implanted ICD. CONCLUSIONS: ICD replacement is associated with a doubled risk for pocket-related surgical re-interventions. Furthermore, the need for re-intervention increases with every consecutive replacement.