Rate, Time Course and Predictors of Implantable Cardioverter Defibrillator Infections: An Analysis from the SIMPLE trial

Abstract Background The number of implantable cardioverter defibrillator (ICD) infections is increasing due to an increased number of ICD implants, higher-risk patients and more frequent replacement procedures, which carry a higher risk of infection. Reducing the morbidity, mortality and cost of ICD-related infections requires an understanding of the current rate of this complication and its predictors. Methods The SIMPLE trial randomized 2 500 ICD recipients to defibrillation testing or not. Over an average of 3.1 years, patients were seen every 6 months and examined for evidence of ICD infection; which was defined as requiring device removal and/or intravenous (IV) antibiotics. Results Within 24 months, 21 patients (0.8%) developed infection. Fourteen patients (67%) with infection presented within 30 days, 20 patients by 12 months and only one beyond 12 months. Univariate analysis demonstrated that patients with primary electrical disorders (3 patients, p=0.009) and those with a secondary prevention indication (13 patients, p=0.0009) were more likely to develop infection. Among the 2.2% of patients who developed an ICD wound hematoma, 10.4% developed an infection. Among the 8.3% of patients requiring an ICD re-intervention, 1.9% developed an infection. Conclusions This cohort of ICD recipients at high-volume centers have a low risk of device-related infection. However; strategies to reduce wound hematoma and the need for ICD re-intervention could further reduce the rate of infection.