Optimal Shock Energy for Electrical Cardioversion of Atrial Fibrillation

NCT07610980 | Not Yet Recruiting

• 1 other identifier: MotolHomolkaUH
• Study Type: interventional
• Target: 400
• Locations: 0 countries
• Sites: N/A

Brief Summary

Introduction For elective electrical cardioversion of atrial fibrillation, the recommended standard is the administration of a biphasic direct current shock. However, there is considerable variability among physicians regarding the choice of the initial shock energy, as current clinical guidelines do not specify it precisely. The guidelines of American cardiology societies recommend a shock intensity of at least 200 J, while the European Society of Cardiology guidelines do not comment on shock energy at all. Evidence from a previous randomized clinical trial has shown that using a higher initial shock energy (360 J) is more effective, safe, and reduces the cumulative delivered energy, since lower initial shock energy more frequently requires repeated shocks. The safety of the maximal-energy protocol was demonstrated in this study, among other by the absence of myocardial injury as assessed by cardiac troponin I levels measured 4 hours after electrical cardioversion. However, in this study, the maximal initial shock energy protocol was compared with a low-energy escalating protocol (125-150-200 J), which is no longer supported by current clinical guidelines. Objective The primary objective of the study is to compare the efficacy (short-term maintenance of sinus rhythm and the need for repeated shocks) of two regimens commonly used in clinical practice: 200-360-360 J and 360-360-360 J. Secondary objectives are to identify factors that would justify the use of either lower or higher initial shock energy. Another secondary objective is to confirm the safety of the maximal initial shock energy protocol by assessing the biomarker of acute stress (copeptin) in a subpopulation of patients (n = 60). Methods The main inclusion criterion for the study is the presence of atrial fibrillation or atypical atrial flutter and a clinical indication for electrical cardioversion raised an independent cardiologist. The main exclusion criterion is the presence of typical atrial flutter or focal atrial tachycardia, for which lower shock energy is recommended. This is a prospective, randomized, single-blind (patient) study in which patients will be randomly assigned in a 1:1:1 ratio either to (i) 200-360-360 J protocol, (ii) 360-360-360 J protocol, or (iii) individualized selection of one of the above protocols based on additional parameters. I one of parameters next parameters is met, the 360-360-360 J protocol will be applied, if not, the 200-360-360 J protocol will be applied: Left atrial size \> 55 mm, duration of the arrhythmia \> 12 months, BMI \> 30 kg/m2, chest circumference \> 120 cm. Since chest dimensions and the amount of subcutaneous fat may influence resistance to electrical current and thereby reduce the delivered electrical energy, chest dimensions and configuration will be evaluated prior to electrical cardioversion in addition to height and weight. The procedure itself (electrical cardioversion) will then be performed according to the standard institutional clinical practice.

Conditions

Atrial Fibrillation (AF)

Outcome Measures

Primary Outcomes (1)

• Presence of sinus rhythm in 1, 5 and 120 minutes after electrical shock.

  Presence of sinus rhythm will be assessed by experienced cardiologist using 3-lead ECG monitor (IntelliVue MP, Philips). If it cannot be concluded about the presence of sinus rhythm from 3-lead ECG monitor, standard 12-lead ECG will be performed using SE-1200 Express machine (EDAN).

  2 hours

Secondary Outcomes (2)

• Cummulative shock energy

  5 minutes

• Myocardial stress and injury

  45 minutes

Study Arms (3)

200J protocol

EXPERIMENTAL

Protocol of 200-360-360J will be applied

Procedure: Direct current biphasic electrical cardioversion; Diagnostic Test: blood sampling

360J protocol

EXPERIMENTAL

Protocol of 360-360-360J will be applied

Procedure: Direct current biphasic electrical cardioversion; Diagnostic Test: blood sampling

Individual protocol

EXPERIMENTAL

Protocol 200-360-360J or 360-360-360J will be selected according to other criteria

Procedure: Direct current biphasic electrical cardioversion; Diagnostic Test: blood sampling

Interventions

Direct current biphasic electrical cardioversion PROCEDURE

Direct current biphasic electrical cardioversion using Lifepak 20e (Medtronic) external defibrilator will be applied in antero-lateral vector.

200J protocol; 360J protocol; Individual protocol

blood sampling DIAGNOSTIC_TEST

6 mL blood samples will be taken from periferal vein before electrical cardiac version and 45 minutes after electrical cardiac version to assess biomarkers of stress and myocardial injury in 60 subjects.

200J protocol; 360J protocol; Individual protocol

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Atrial fibrillation
• Atypical atrial flutter
• Indication for elective electrical cardiac version made by independent physician

You may not qualify if:

• Typical atrial flutter
• Focal atrial tachycardia

Sponsors & Collaborators

• Motol and Homolka University Hospital: lead

MeSH Terms

Conditions

Atrial Fibrillation

Interventions

Blood Specimen Collection

Condition Hierarchy (Ancestors)

Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Specimen Handling; Clinical Laboratory Techniques; Diagnostic Techniques and Procedures; Diagnosis; Punctures; Surgical Procedures, Operative; Investigative Techniques

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Study Record Dates

• First Submitted: May 13, 2026
• First Posted: May 28, 2026
• Study Start: May 18, 2026
• Primary Completion (Estimated): December 1, 2028
• Study Completion (Estimated): June 1, 2029
• Last Updated: May 28, 2026

Record last verified: 2026-05