Electrical energy by electrode placement for cardioversion of atrial fibrillation: a systematic review and meta-analysis

Objective Electrode patch position may not be critical for success when cardioverting atrial fibrillation (AF), but the relevance of applied electrical energy is unclarified. Our objective was to perform a meta-analysis of randomised trials to examine the dose–response relation between energy level and cardioversion success by electrode position in elective cardioversion. Methods We searched PubMed, Embase, The Cochrane Library, Google Scholar and Scopus Citations. Inclusion criteria were randomised controlled trials using biphasic shock waves and self-adhesive patches, and publication date from 2000 to 2023. We used random-effects dose-response models to meta-analyse the relation between energy level and cardioversion success by anterolateral and anteroposterior position. Random-effects models estimated pooled risk ratios (RR) for cardioversion success after the first and the final shocks between the two electrode positions. Results We included five randomised controlled trials (N=1078). After the first low-energy shock, the electrode position was not significantly associated with the likelihood of successful cardioversion (pooled RR anterolateral vs anteroposterior placement 1.28, 95% CI 0.93 to 1.76, with considerable heterogeneity). After a high-energy final shock, there was no evidence of an association between the electrode position and the cumulative chance of cardioversion success (pooled RR anterolateral vs anteroposterior 1.05, 95% CI 0.97 to 1.14). Regardless of electrode position, cardioversion success was significantly less likely with shock energy levels < 200J compared with 200J. Conclusion Evidence from contemporary randomised trials suggests that higher level of electrical energy is associated with higher conversion rate when cardioverting AF with a biphasic shockwave. Positioning of electrodes can be based on convenience.