Successful implantation of cardiovascular-defibrillator systems in patients with elevated defibrillation thresholds

Abstract Objectives . The purpose of this study was to conduct a retrospective analysis of 16 patients with high initial defibrillation thresholds in whom a three-electrode system was used to lower defibrillation threshold and permit implantation of a cardioverter-defibrillator system. Background . Patients with high defibrillation thresholds(>25 J) are uncommon but may be problematic to physicians implementing cardioverter-defibrillator systems. Most conventional systems use two defibrillating electrodes, most commonly two epicardial patches. When defibrillatation threshold remain elevated despite extensive testing of a two-electrode system, a third electrode can be incorporated and tested. However, few published data exist on the use of a three-electrode system in patients with high defibrillation thresholds. Methods . After failure to achieve satisfactory defibrillation thresholds Results . In all 16 patients, satisfactory defibrillation thresholds were achieved and a cardioverter-defibrillator was implanted (95% confidence interval [CI] = 0% to 21%). The mean final defibrillation threshold using the revised three-electrode system was 19.5 ± 3.7 J (p Conclusion . Patients with high initial defibrillation thresholds can generally undergo successful cardioverter-defibrillator implantation with a tnree-electrode system if enough electrode configurations are tested after a third electrode is incorporated.