Comparing shock energy for treating persistent atrial fibrillation

A Randomised Trial of Shock Energy for Electrical Cardioversion of Persistent Atrial Fibrillation

Not applicable Interventional Wellington Hospital · NCT05903170

This study is testing whether using different shock levels from defibrillators can help people with persistent atrial fibrillation get their heart rhythm back to normal.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment100 (estimated)
Ages18 Years and up
SexAll
SponsorWellington Hospital Government
Locations1 site (Wellington, Wellington Region)
Trial IDNCT05903170 on ClinicalTrials.gov

What this trial studies

This clinical trial aims to compare the effectiveness of two defibrillators with different maximum energy outputs in cardioverting patients with persistent atrial fibrillation. Participants will be randomly assigned to receive shocks at either 200J or 360J, with a maximum of three shocks administered based on their assigned energy level. If the lower energy level fails to restore normal rhythm, a fourth shock at the higher energy level will be given. Blood tests will be conducted the day after the procedure to assess outcomes.

Who should consider this trial

Good fit: Ideal candidates include adults over 18 years old who are undergoing elective outpatient or non-emergent inpatient cardioversion for atrial fibrillation and are reliably anticoagulated.

Not a fit: Patients who may not benefit include those with contraindications to anticoagulation, atrial flutter, or those requiring emergent cardioversion.

Why it matters

Potential benefit: If successful, this study could lead to improved cardioversion techniques for patients with atrial fibrillation, enhancing treatment efficacy and patient outcomes.

How similar studies have performed: While there have been studies on shock energy in cardioversion, this specific head-to-head comparison of two defibrillators is novel and has not been previously undertaken.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Age \>18
* Patients undergoing either elective outpatient or non-emergent inpatient cardioversion for atrial fibrillation
* Eligible for anticoagulation
* Reliably anticoagulated for ≥three weeks prior to cardioversion, AF onset within 48hrs of cardioversion, or left atrial thrombus excluded on transoesophageal echocardiogram
* Able to consent to cardioversion, and study participation

Exclusion Criteria:

* Contraindication to anticoagulation
* Atrial flutter
* Emergent cardioversion
* Implantable cardiac device (PPM or ICD)
* Unable to consent to cardioversion and/or study participation
* Pregnancy

Where this trial is running

Wellington, Wellington Region

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Atrial FibrillationAtrial fibrillationElectrical cardioversion
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.