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Related Experiment Video

Updated: Jul 2, 2026

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation

Catheter Ablation in Combination With Left Atrial Appendage Closure for Atrial Fibrillation

Published on: February 26, 2013

Double external direct-current shocks for refractory atrial fibrillation.

P Bjerregaard¹, A El-Shafei, D L Janosik

¹Saint Louis University Health Sciences Center, Missouri, USA.

The American Journal of Cardiology

|April 6, 1999

Summary

Double external direct-current (DC) shocks safely restored sinus rhythm in two-thirds of atrial fibrillation patients resistant to single shocks. This advanced cardioversion technique offers a promising alternative for refractory cases.

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Area of Science:

Cardiology
Electrophysiology

Background:

Atrial fibrillation (AF) is a common arrhythmia.
Patients refractory to single external direct-current (DC) cardioversion require alternative treatments.

Purpose of the Study:

To evaluate the safety and efficacy of a sequential double external DC shock protocol for AF.
To assess the success rate of double shocks in patients refractory to single shocks.

Main Methods:

A prospective study was conducted on patients with AF exceeding 1-month duration.
A specific sequence of single and double external DC shocks was administered.
Configurations included anterior-posterior and apex-anterior electrode placements with varying energy levels.
Double shocks were delivered almost simultaneously using two defibrillators.

Main Results:

The double external DC shock protocol was found to be safe.
Approximately two-thirds of patients refractory to single DC shocks achieved sinus rhythm with double shocks.
The study demonstrated a significant success rate for this advanced cardioversion method.

Conclusions:

Sequential double external DC shocks are a safe and effective strategy for AF cardioversion.
This method provides a viable option for patients with AF refractory to conventional single-shock cardioversion.
The findings support the use of double shocks in clinical practice for difficult-to-convert AF cases.