Single beta-blocker or combined amiodarone therapy in implantable cardioverter-defibrillator and cardiac resynchronization therapy—defibrillator patients: Insights from the German DEVICE registry

Abstract

Background

Because of its antiarrhythmic potency and due to the lack of alternatives, amiodarone is often used for antiarrhythmic therapy in patients with ICD or CRT-D systems. To date, robust data on the safety and clinical benefit of amiodarone therapy in these patients are missing

Objective

This study was designed to assess the periprocedural and post-procedural outcome of combined therapy with beta-blockers plus amiodarone compared to treatment with single beta-blockers in this "real life" cohort of ICD recipients of the German DEVICE registry.

Methods

4,499 patients who underwent ICD implantation, revision, or upgrade in 49 centers participating in the German DEVICE Registry were enrolled 03/2007-02/2014.

Results

Amiodarone had no significant effect on the success of defibrillation testing. Early implantation-associated complications were similar between the groups. One-year overall mortality was, however, significantly higher in the beta-blocker plus amiodarone cohort (adjusted HR 2.09; p<0.001). Interestingly, amongst the surviving patients, amiodarone was not associated with a significantly reduced risk of ICD discharges, syncopal events. Further, the occurrence of VT storm or incessant VTs and the number of patients scheduled for intracardiac ablation did not differ among both groups while the rate of rehospitalization was lower in the cohort with sole beta-blockers.

Conclusions

While amiodarone has no adverse effect on the success of defibrillation testing, our data suggest an increased all-cause mortality under amiodarone therapy, especially in the subgroups of patients with sinus rhythm or severely reduced left ventricular function. In surviving patients, rates of arrhythmic events were comparable.