Performance After Cardiac Ablation in Endurance Athletes for Atrial Fibrillation

NCT07726056 | Recruiting DMC

• 1 other identifier: 3113
• Study Type: interventional
• Target: 100
• Locations: 2 countries
• Sites: 5

Brief Summary

The relationship between exercise and atrial fibrillation (AF) seems to follow a J-shaped curve: while moderate activity reduces AF risk, both insufficient and excessive endurance exercise increase susceptibility. In athletes, standard treatments such as antiarrhythmic drugs often provide only partial symptom control and may impair performance through fatigue, chronotropic incompetence and side effects. Pulmonary vein isolation (PVI) may offer a more definitive therapeutic option but carries risks of atrial fibrosis, stiffening, and altered autonomic regulation, which may also influence exercise capacity. The investigators hypothesize that ablation will have a significant impact-either beneficial or detrimental-on the physical performance of athletes with AF. However, existing evidence is limited to small studies with inconsistent findings, underscoring the need for a dedicated study. This prospective, multicentre interventional study will assess the effects of cardiac ablation in 100 endurance athletes with AF. Participants will undergo comprehensive pre- and post-ablation phenotyping, including electrocardiogram (ECG), cardiopulmonary exercise testing (CPET), echocardiography, Holter monitoring, and detailed training data collection (efficiency factor, acute and chronic training load). Clinical follow-up will extend to 12 months post-ablation. The primary endpoint is the change in peak VO₂ (mL/kg/min) measured before ablation and after the procedure. Secondary analyses will explore:

• Autonomic adaptations: including changes in maximum heart rate, heart rate recovery, heart rate reserve, and heart rate variability.
• Cardiac function: alterations in diastolic and atrial function assessed by echocardiography.
• Training and performance: objective measures such as efficiency factor, decoupling, functional threshold power, critical power, and acute and chronic training load.
• Technique comparison: differences in outcomes between pulsed field and radiofrequency ablation (e.g. atrial function, troponin release, …).
• Sex-specific effects: recognising the underrepresentation of women in sports cardiology research, the investigators will include female athletes according to incidence and evaluate potential differences in treatment response between sexes.
• Predictors of AF recurrence in endurance athletes

Conditions

Atrial Fibrillation (AF)

Keywords

Athletes; Sports Cardiology; Atrial Fibrillation; Ablation; Endurance; Performance

Outcome Measures

Primary Outcomes (1)

• Change in peak VO2

  The primary endpoint is the change in peak VO₂ (mL/kg/min) between baseline (before ablation) and follow-up.

  From enrollment to 8 weeks post-ablation.

Study Arms (1)

Endurance athletes

OTHER

Other: Ablation

Interventions

Ablation OTHER

The ablation procedure will be limited to pulmonary vein isolation (PVI) alone, without additional extensive ablation such as posterior wall, isthmus, or linear lesions on the left or right atrium. If atrial flutter is documented in the patient's medical history, or if it is strongly suspected or inducible during the electrophysiology study, a cavotricuspid isthmus (CTI) ablation will be performed. The choice of energy modality (e.g., pulsed field ablation, cryoablation, or radiofrequency ablation) will be at the discretion of the electrophysiologist, according to procedural goals and institutional standards. When deemed appropriate by the treating physician, an assessment of the underlying arrhythmogenic substrate using electroanatomical mapping may be undertaken; however, this is not mandatory. Similarly, if available and preferred by the participating centre, intra-atrial pressures may be recorded, though this is also optional. Following the ablation, a one-month blanking period wil

Endurance athletes

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18-80 years
• Participation in endurance sports (≥4 hours/week)
• Diagnosis of atrial fibrillation
• Capturing training data through commercially available platforms (e.g. Strava, TrainingPeaks, …) or willingness to start collecting training data and working with these commercially available platforms prospectively

You may not qualify if:

• No training data available
• History of cardiovascular disease (including ischemic heart disease, cardiomyopathy, valvular heart disease, primary electrical disorders, or congestive heart failure)
• Active smoking

Sponsors & Collaborators

• Baerum Hospital, Vestre Viken Hospital Trust, Gjettum, Norway: collaborator
• University Hospital of Leuven Leuven: lead
• St Vincent's Hospital Melbourne: collaborator
• Royal Adelaide Hospital: collaborator
• University Hospital, Antwerp: collaborator
• Ziekenhuis Oost Limburg (ZOL) Hospital Genk, Belgium: collaborator
• Jessa Ziekenhuis Hasselt: collaborator

Study Sites (5)

St. Vincent's Hospital

Melbourne, Australia

RECRUITING

Universitair Ziekenhuis Antwerpen

Antwerp, Antwerpen, 2000, Belgium

RECRUITING

ZOL Genk

Genk, Limburg, 3600, Belgium

RECRUITING

Jessa Hospital, Department of Cardiology

Hasselt, Limburg, 3500, Belgium

RECRUITING

UZ Leuven

Leuven, Vlaams-Brabant, 3000, Belgium

RECRUITING

MeSH Terms

Conditions

Atrial Fibrillation

Condition Hierarchy (Ancestors)

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

Study Officials

• Guido Claessen, MD, PhD

  University of Hasselt, LCRC

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Boris Delpire, MD

CONTACT

+32477399875; boris.delpire@uhasselt.be

Guido Claessen, MD, PhD

CONTACT

claessen.guido@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD, PhD Candidate Sports Cardiology

Study Record Dates

• First Submitted: July 21, 2026
• First Posted: July 24, 2026
• Study Start: March 1, 2026
• Primary Completion (Estimated): December 31, 2030
• Study Completion (Estimated): December 31, 2032
• Last Updated: July 27, 2026

Record last verified: 2026-07

Locations

AU (1); BE (4)