Anterior-posterior versus anterior-lateral electrode position for biphasic cardioversion of atrial fibrillation

Abstract

Objective: The aim of the study was to assess if the anterior-posterior electrode position for the conversion of atrial fibrillation using biphasic waveform shocks is more effective and needs less energy compared with the anterior-lateral position.

Background: In several studies, anterior-posterior electrode position has been demonstrated to be superior to anterior-lateral position for the termination of atrial fibrillation using monophasic waveform shocks, but data regarding biphasic shocks are still emerging.

Patients and methods: Our prospective, randomized study enrolled 103 consecutive patients with atrial fibrillation who were referred for elective cardioversion. The electrode position was randomly selected to be anterior-lateral (n=55) and anterior-posterior (n=48). A step-up protocol of 100, 150, 200, and 300 J biphasic truncated exponential waveform shocks was used. RESULTS. Two groups with different paddle position were compared. There was no difference in age, gender, body mass index, ejection fraction, or left atrial size between the groups. Sinus rhythm restoration failed only in one patient in each group. Energy of 100 J was sufficiently effective in most patients in both groups.

Conclusions: The anterior-posterior electrode position during transthoracic cardioversion using biphasic waveform shocks has no advantages compared with more comfortable and common anterior-lateral position.