Active compression versus standard anterior-posterior defibrillation for external cardioversion of atrial fibrillation: A prospective randomized study

Abstract

Electrical cardioversion is the first-line rhythm control therapy for symptomatic persistent atrial fibrillation (AF). Contemporary use of biphasic shock waveforms and anterior-posterior positioning of defibrillation electrodes have improved cardioversion efficacy; however, it remains unsuccessful in >10% of patients. The purpose of this study was to assess the efficacy of applying active compression on defibrillation electrodes during AF cardioversion. We performed a bicenter randomized study including patients referred for persistent AF cardioversion. Elective external cardioversion was performed by a standardized step-up protocol with increasing biphasic shock energy (50-100-150-200 J). Patients were randomly assigned to standard anterior-posterior defibrillation or to defibrillation with active compression applied over the anterior electrode. If sinus rhythm was not achieved at 200 J, a single crossover shock (200 J) was applied. Defibrillation threshold, total delivered energy, number of shocks, and success rate were compared between groups. We included 100 patients, 50 in each group. In the active compression group, defibrillation threshold was lower (103.1 ±49.9 J vs 130.4 ± 47.7 J; P = .008), as well as total delivered energy (203 ± 173.3 J vs 309 ± 213.5 J; P = .0076) and number of shocks (2.2 ± 1.1 vs 2.9 ± 1.2; P = .0033), and cardioversion was more often successful (48 of 50 patients [96%] vs 42 of 50 patients [84%]; P = .0455) than that in the standard anterior-posterior group. Crossover from the compression group to the standard group was not successful (0 of 2 patients), whereas crossover from the standard group to the compression group was successful in 50% of patients (4 of 8). Active compression applied to the anterior defibrillation electrode is more effective for persistent AF cardioversion than standard anterior-posterior cardioversion, with lower defibrillation threshold and higher success rate.