Is Fluoroscopic Electrode Positioning Improving the Clinical Efficacy of External Biphasic Cardioversion in Patients with Atrial Fibrillation?

Abstract

The use of external direct current (DC) transthoracic capacitor discharge to terminate atrial fibrillation (AF) was first reported in 1962 by Lown et al. [1]. However, external DC cardioversion with a monophasic damped sine waveform in patients with AF is ineffective in 6%-50% of cases [2-4]. An alternative when conventional DC cardioversion fails is low-energy internal cardioversion, performance of which carries increased risk because of the catheter insertion [5]. Recently, a biphasic shock waveform have been shown to be superior to monophasic shock in the treatment of AF patients. Mittal et al. [6] confirmed that rectilinear biphasic shock was more effective than monophasic shock for external atrial cardioversion in a prospective multicenter trial. The cumulative efficacy with the biphasic waveform was significantly greater than that with the monophasic waveform (94% vs 79%,p=0.005) [6].

The aim of the study was to compare the clinical efficacy of external cardioversion with rectilinear biphasic shock with fluoroscopy-guided electrode positioning versus standard electrode positioning (right anterior and left posterior) to increase the success rate of standard external cardioversion and avoiding the need of internal cardioversion in patients with AF.