Single vs. Dual-DCCV in Obese Patients

Study Overview
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Brief Summary
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Currently, the usual initial strategy for direct current cardioversion (DCCV) typically involves delivering 200J of electricity between two pads placed in the anterior and posterior positions (i.e., one on the chest and one on the back). However, this technique may be less likely to result in successful cardioversion in obese patients (BMI ≥30 kg/m2). Failure to achieve sinus rhythm then necessitates additional shocks, which still may ultimately fail to terminate the patient's atrial fibrillation, thereby increasing the likelihood of adverse events from multiple cardioversion attempts Dual-DCCV is a technique in which four pads are used to deliver two simultaneous shocks of 200J, totaling 400J. Guidelines published by the American Heart Association/American College of Cardiology/Heart Rhythm Society and the European Society of Cardiology provide only general guidance regarding the appropriate technique and energy selection in patients undergoing cardioversion, with no specific recommendations pertaining to dual-DCCV or obese patients. This study aims to assess the safety and efficacy of dual-DCCV as an initial treatment strategy, compared to standard single-DCCV, in the obese population.

Detailed Description
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Patients with sustained atrial fibrillation and obesity who are scheduled for a cardioversion for atrial fibrillation will provide written informed consent prior to starting the procedure. Patients will be randomly assigned in a 1:1 fashion to either single-DCCV or dual-DCCV treatment. All patients will have 4 defibrillation pads placed: two pads placed in the right infraclavicular region and left flank region, plus two pads placed in the left infraclavicular and right flank region. All patients will receive moderate sedation immediately prior to and during cardioversion. Patients randomized to single-DCCV will be given a single 200J shock using the primary (or right anterior-left posterior) pair of pads. Patients assigned to dual-DCCV will receive two simultaneous 200J shocks (from both the primary and secondary set of defibrillator pads), totaling 400J delivered. Patients in the single-DCCV group whose initial shock fails to restore normal sinus rhythm will be crossed over to the dual-DCCV group. Patients in the dual-DCCV group will receive up to three attempts at DCCV, as needed, at the discretion of the attending electrophysiologist. One hour after cardioversion is completed, patients will be asked if they experienced any chest discomfort related to cardioversion and, if applicable, will rate their chest discomfort using a pain scale from 0-10.

Official Title
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Efficacy and Safety of Dual Direct Current Cardioversion Versus Single Direct Current Cardioversion as an Initial Treatment Strategy in Obese Patients

Conditions
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Atrial Fibrillation

Intervention / Treatment
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* Device: Direct Current Cardioversion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 years of age Atrial fibrillation (paroxysmal, persistent, and long-standing persistent) Obesity (defined as body mass index [BMI] ≥35 kg/m2). Of note, our current institutional protocol uses weight >250 lbs as an indication for dual-DCCV. An average height of 70 inches equates to BMI  35 kg/m2 Adequate anticoagulation at the time of the cardioversion (one of the following): Coumadin with an INR >2 Direct oral anticoagulants (apixaban, dabigatran, rivaroxaban, or edoxaban) Subcutaneous low molecular-weight heparin or IV unfractionated heparin If the duration of atrial fibrillation is >48 hours (or unknown): trans-esophageal echocardiography (TEE) performed prior to cardioversion to document the absence of a left atrial thrombus, or continuous therapeutic anticoagulation for a minimum of 3 weeks prior to cardioversion Able to maintain uninterrupted therapeutic anticoagulation after cardioversion, for at least one month Exclusion Criteria: Contraindication to cardioversion Not on adequate anticoagulation Emergent cardioversion Incarceration Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Patients will be randomly assigned in a 1:1 fashion to either single-DCCV or dual-DCCV treatment. All patients will have 4 defibrillation pads placed: two pads placed in the right infraclavicular and left flank regions, plus two pads placed in the left infraclavicular and right flank regions. Patients randomized to single-DCCV will receive a single 200J shock using the primary (or right anterior-left posterior) pair of pads. Patients assigned to dual-DCCV will receive two simultaneous 200J shocks (from both the primary and secondary set of defibrillator pads), totaling 400J delivered. Patients in the single-DCCV group whose initial shock fails to restore normal sinus rhythm will be crossed over to the dual-DCCV group. Patients in the dual-DCCV group will receive up to three attempts at DCCV, as needed, at the discretion of the attending electrophysiologist.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: single-DCCV group<br>Patients randomized to single-DCCV will be given a single 200J shock using the primary (or right anterior-left posterior) pair of pads. | Device: Direct Current Cardioversion<br>* The patient is sedated and shocked using an external defibrillator to terminate the arrhythmia and restore a normal intrinsic rhythm (i.e., normal sinus rhythm).<br>|
| Experimental: dual-DCCV group<br>Patients assigned to dual-DCCV will receive two simultaneous 200J shocks (from both the primary and secondary set of defibrillator pads), totaling 400J delivered. | Device: Direct Current Cardioversion<br>* The patient is sedated and shocked using an external defibrillator to terminate the arrhythmia and restore a normal intrinsic rhythm (i.e., normal sinus rhythm).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Successful return to sinus rhythm confirmed via rhythm strip ECG (regardless of duration) immediately following DCCV | Participant cardiac rhythm verified to have returned to sinus rhythm by single-lead rhythm strip ECG obtained via the defibrillator device. | 0-1 hours |