Dual vs. Single Cardioversion in Patients With Obesity - Dual vs. Single DCCV

Contribution To Literature:

The Dual vs. Single DCCV trial showed that in patients with obesity and AF, dual DCCV is more effective than single DCCV in restoring sinus rhythm without increased patient discomfort or periprocedural risk.


The goal of the trial was to determine the efficacy and safety of dual direct-current cardioversion (DCCV) compared with single DCCV in patients with obesity and atrial fibrillation (AF) undergoing elective electrical cardioversion.

Study Design

  • Multicenter
  • Single-blind
  • Randomized

Patients with AF and class ≥2 obesity were randomized in a 1:1 fashion to undergo elective cardioversion using a dual (400 J, n = 99) or single (200 J, n = 101) biphasic DCCV configuration. The primary pads were placed on the anterior right chest below the clavicle and left lower posterolateral chest wall. Secondary pads, which were placed on all patients but not utilized in the single DCCV arm, were positioned on the anterior left chest and right lower posterolateral wall. Up to two additional cardioversion attempts, both with dual DCCV, could be performed if the initial attempt failed to restore sinus rhythm.

  • Total number of enrollees: 200
  • Median patient age: 68 years
  • Percentage female: 37%

Inclusion criteria:

  • Age ≥18 years
  • Body mass index (BMI) ≥35 kg/m2
  • Paroxysmal, persistent, or longstanding persistent AF
  • Therapeutic anticoagulation for ≥3 weeks prior or transesophageal echocardiogram without left atrial (LA) thrombus if AF duration >48 hours or unknown

Exclusion criteria:

  • Emergent cardioversion
  • Any contraindication to cardioversion
  • Inability to take therapeutic anticoagulation

Other salient features/characteristics:

  • Mean BMI: 41.2 kg/m2
  • AF onset <3 months prior: 41%
  • Prior DCCV: 39%
  • Mean LA volume index: 48 mL/m2

Principal Findings:

The primary outcome, successful first cardioversion to sinus rhythm for dual vs. single DCCV: 98% vs. 86%, p = 0.002; adjusted odds ratio 6.7 (95% confidence interval 3.3-13.6), p = 0.01.

Secondary outcomes:

  • Failed single DCCV successfully cardioverted on subsequent attempts: 14/14 (100%)
    • Second attempt: 86%
    • Third attempt: 14%
  • Failed dual DCCV successfully cardioverted on subsequent attempts: 1/2 (50%)
  • Median post-procedure chest pain visual analog scale score: 0
  • Adverse events before post-procedure discharge: 0%


Obesity is a known risk factor for electrical cardioversion failure in AF. Although dual DCCV in this setting has previously been described, the current data represent the first randomized evidence to support both the high efficacy and safety profiles of this strategy. The observed benefit may be due to both increased energy delivery and possibly the additional shock vector from the secondary pads. Notably, crossover from the small number of failed single DCCVs resulted in 100% success on subsequent attempts. Over 90% of patients were enrolled from one center with no failed cardioversions at the remaining two sites, thus precluding site-stratified analysis. Comparison of dual DCCV with strategies such as manual electrode pressure or maximum-fixed biphasic energy delivery, either alone or in combination, may be helpful in clarifying the optimal cardioversion strategy in this population.


Aymond JD, Sanchez AM, Castine MR, et al. Dual vs Single Cardioversion of Atrial Fibrillation in Patients With Obesity: A Randomized Clinical Trial. JAMA Cardiol 2024;May 22:[Epublished].

Clinical Topics: Arrhythmias and Clinical EP, EP Basic Science, Atrial Fibrillation/Supraventricular Arrhythmias, Prevention

Keywords: Atrial Fibrillation, Electric Countershock, Obesity

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