[Influence of amiodarone on defibrillation threshold and perioperative complications in patients with implantable cardioverter-defibrillator with transvenous electrodes and biphasic shocks].

In order to evaluate the safety of implantation of a third generation automatic cardioverter-defibrillator (ICD) in patients with amiodarone therapy, we retrospectively analyzed implantation results and perioperative complications in 17 consecutive patients with continued amiodarone therapy and 38 patients without antiarrhythmics at first ICD implantation.ICD implantation could be performed successfully in all 55 patients using a transvenous electrode system. In one of 17 patients with amiodarone (6%) versus three of 38 patients without antiarrhythmics (8%), additional implantation of a subcutaneous patch electrode was necessary to achieve a defibrillation threshold </=24 Joules (p=n.s.). Intraoperatively tested defibrillation threshold was 13+/-5 Joules in the amiodarone group versus 12+/-5 Joules in patients without antiarrhythmics (p=n.s.). The incidence of perioperative complications was not different between patients with amiodarone and patients without antiarrhythmics.In summary, patients with amiodarone did not have higher defibrillation thresholds or a higher incidence of perioperative complications than patients without antiarrhythmics. The occasionally postulated discontinuation of amiodarone with subsequent waiting for the elimination of this antiarrhythmic drug is unnecessary. For final clarification of the influence of amiodarone-therapy on the defibrillation threshold in patients with third generation ICDs, a prospective randomized study in a large patiente cohort with standardized study conditions would be required.