A stepwise external cardioversion protocol for atrial fibrillation to maximize acute success rate

Abstract

Aims Cardioversion is a very commonly performed procedure for persistent atrial fibrillation (AF). However, there is no well-defined protocol to address failed external electrical direct current cardioversion. The aim of the study is to test the efficacy of a pre-defined stepwise cardioversion protocol for patients with persistent AF of ≤12 months. Success was the achievement of sinus rhythm. Methods and results The study population included patients with persistent AF of ≤12 months duration requiring rhythm management. Patients were offered cardioversion using a pre-defined stepwise protocol using different electrode placement locations, applying compression at end of expiration, and higher energy delivered simultaneously through two defibrillators. : A total of 414 patients were included in the study, of which 362 (87.4%) required a single successful cardioversion. The remaining 52 (12.5%) patients required additional cardioversion attempts using the stepwise cardioversion protocol with an overall success rate of 99.3%. Two simultaneous defibrillators were required in 14 patients (3.4%). Patients with multiple cardioversions (13.5%) experienced more local skin irritation and pain compared with patients with single cardioversion (13.5% vs. 3.5%, P = 0.004). The predictor for the need for multiple cardioversion attempts is high body mass index, while high transthoracic impedance is associated with failed cardioversion. No major complications were observed during the study. Conclusion The stepwise cardioversion protocol has a high success rate of >99% and can be safely performed in outpatient or inpatient settings.

Dual vs Single Cardioversion of Atrial Fibrillation in Patients With Obesity

“…Consequently, efforts have been directed toward exploring alternative strategies to overcome these obstacles, including manual pressure on the electrodes, alteration of electrode positioning, pretreatment with antiarrhythmic drugs, and increasing shock energy. 12,[40][41][42][43] In a study using increasing biphasic shock energy (50 J to 100 J to 150 J to 200 J) and anterior-posterior electrode positioning, the investigators found that application of pressure to the anterior electrode improved cardioversion success (96% vs 84%), reduced defibrillation threshold, and decreased both total shock energy and the required number of shocks. 43 In another study, cardioversion outcomes in patients with obesity (BMI ≥30) using various shock vectors (anteroposterior vs anteroapical) and pressure (handheld paddles vs adhesive patches) were evaluated in a 1:1:1:1 randomized clinical trial of 125 patients, with each cohort receiving escalating shock energy (100 J to 200J, with a third shock using crossover to patches or paddles using 200 J).…”

“…It has been postulated that cardioversion failure in patients with obesity results from higher transthoracic impedance, larger interelectrode distance, and larger atrial size. Consequently, efforts have been directed toward exploring alternative strategies to overcome these obstacles, including manual pressure on the electrodes, alteration of electrode positioning, pretreatment with antiarrhythmic drugs, and increasing shock energy …”

Manual Chest PRESSURE during Direct Current Cardioversion for Atrial Fibrillation: A Randomised Control Trial (PRESSURE-AF)

“…The main predictors of cardioversion failure are increased body mass index, male sex and higher transthoracic impedance. (9, 10)…”

Is Right Atrial Remodeling an Additional Marker for the Progression of Atrial Fibrillation?

“…Although the immediate success rate of DCCV is high, 3) predicting the possibility of failure is important to minimize unnecessary thromboembolic risk. Several clinical and echocardiographic factors influence the success of DCCV.…”