Restoring Sinus Rhythm Using Dual-Shock Technique in Patients With Atrial Fibrillation (DUAL-SHOCK)

Restoring Sinus Rhythm Using DUAL-electrical SHOCK Technique: the DUAL-SHOCK Trial

The goal of this clinical trial is to assess the efficacy and acute safety of the dual electrical cardioversion (ECV) technique compared with the conventional ECV in patients with persistent atrial fibrillation. The main question it aims to answer are:

• Is dual ECV more effective than conventional ECV to achieve sinus rhythm restoration?
• Is dual ECV safe compared with conventional ECV?
• Which are the main factors associated with cardioversion success?

Researchers will compare a dual ECV technique with 400J with dual ECV with 200J and conventional ECV.

Participants will be randomized to one ECV configuration. The primary efficacy endpoint will be considered the percentage of patients with successful cardioversion with the first shock. The coprimary safety endpoint will be the occurrence of adverse events during ECV.

Study Overview

• Status: Not yet recruiting
• Conditions: Atrial Fibrillation; Atrial Fibrillation (AF)
• Intervention / Treatment: Procedure: Conventional Electrical Cardioversion; Procedure: Dual-shock Electrical Cardioversion

• Study Type: Interventional
• Enrollment (Estimated): 177
• Phase: Phase 2; Phase 3

Contacts and Locations

• Study Contact: Name: Martín Negreira-Caamaño, MD, PhD; Phone Number: +34 916839360; Email: martin.negcam@gmail.com

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Diagnosis of persistent AF.
• Effective anticoagulation for at least 3 weeks prior to the procedure or exclusion of intra-atrial thrombus by transesophageal echocardiography within the last 24 hours.
• Informed consent obtained.

Exclusion Criteria:

• Long-standing persistent atrial fibrillation (more than 1 year of uninterrupted AF rhythm).
• Emergency indication (hemodynamic instability).
• Cardiac defibrillation following catheter ablation procedures. Cardiac defibrillation performed during the same procedure will be permitted if it is carried out prior to ablation.
• Pregnancy.
• Age <18 years or legal incapacity.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Sequential Assignment
• Masking: Double

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Conventional Electrical Cardioversion; Conventional ECV with single pad configurataion in antero-lateral or antero-posterior location. Energy deliver: 200J	Procedure: Conventional Electrical Cardioversion; Defibrillation pads will be placed in the anteroposterior or anterolateral position. An initial biphasic shock of 200 J will be delivered. If sinus rhythm is not restored, a second dual shock of 400 J (crossover) will be administered. The procedures will be performed in the designated area for such procedures at each center, under deep sedation in accordance with each center's standard protocols. The choice of medication used for sedation will be at the investigator's discretion. All shocks will be delivered using biphasic energy and ECG-synchronized.
Experimental: Dual-Shock 400J; ECV with dual shock technique. Double pad configuration with electrodes both in antero-lateral and antero-posterior location. Total energy deliver: 400J.	Procedure: Dual-shock Electrical Cardioversion; Two pairs of defibrillation pads connected to two different defibrillators will be used. One pair of pads will be placed in the anterolateral position and the second pair in the anteroposterior position. Both defibrillators will be programmed to deliver a biphasic shock of 100 J each (200 J group) or 200 J each (400 J group) simultaneously. The maximum number of CVE attempts per patient will be 3. The procedures will be performed in the designated area for such procedures at each center, under deep sedation in accordance with each center's standard protocols. The choice of medication used for sedation will be at the investigator's discretion. All shocks will be delivered using biphasic energy and synchronized with the QRS complex.
Experimental: Dual-Shock 200J; ECV with dual shock technique. Double pad configuration with electrodes both in antero-lateral and antero-posterior location. Total energy deliver: 200J.	Procedure: Dual-shock Electrical Cardioversion; Two pairs of defibrillation pads connected to two different defibrillators will be used. One pair of pads will be placed in the anterolateral position and the second pair in the anteroposterior position. Both defibrillators will be programmed to deliver a biphasic shock of 100 J each (200 J group) or 200 J each (400 J group) simultaneously. The maximum number of CVE attempts per patient will be 3. The procedures will be performed in the designated area for such procedures at each center, under deep sedation in accordance with each center's standard protocols. The choice of medication used for sedation will be at the investigator's discretion. All shocks will be delivered using biphasic energy and synchronized with the QRS complex.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Primary Efficacy Outcome - Patients achieving sinus rhythm with the first shock	Percentage of patients achieving sinus rhythm with the first shock deliver. Three consecutive beats in sinus rhythm are neccesary to consider sinus rhythm achieved.	First minute after first shock delivery
Primary Safety Outcome - Adverse events during the procedure	Ocurrence of any complication during the ECV. Arrhythmic recurrences of atrial fibrillation will not be considered as complications.	Before patient are discharged

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Overall Procedural Sucess	Percentage of patients achieving stable sinus rhythm after any number of shocks	The end of the procedure
Overall Intervention-Specific Success	Number of successful shocks / Overall delivered shock within the same pad configuration.	First minute after shock delivery
Total Energy Delivered	Total energy administered (J) before the procedure is completed	End of the procedure
Sub-acute procedural success	Percentage of patients in sinus rhythm at 30 days after the ECV	At 30 (25-35) days after the procedure

Collaborators and Investigators

• Sponsor: Martín Negreira Caamaño

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2026
• Primary Completion (Estimated): December 31, 2027
• Study Completion (Estimated): February 27, 2028

Study Registration Dates

• First Submitted: April 21, 2026
• First Submitted That Met QC Criteria: April 28, 2026
• First Posted (Actual): May 1, 2026

Study Record Updates

• Last Update Posted (Actual): May 7, 2026
• Last Update Submitted That Met QC Criteria: May 1, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: Atrial fibrillation; Electrical Cardioversion; Sinus Rhythm; Persistant atrial fibrillation; Dual-Shock
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Pathological Conditions, Signs and Symptoms; Atrial Fibrillation
• Other Study ID Numbers: 25-129

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Study protocol will be sent for publication
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No