Comparing two pacing methods after heart procedure for atrial fibrillation

CONDUCTion System Pacing Versus Biventricular Pacing After Atrioventricular Node Ablation in Heart Failure Patients With Symptomatic Atrial Fibrillation and Narrow QRS (CONDUCT-AF Trial)

Not applicable Interventional University Medical Centre Ljubljana · NCT05467163

This study is testing whether a new pacing method for the heart can help people with heart failure and atrial fibrillation feel better compared to a traditional pacing method after a specific heart procedure.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment82 (estimated)
Ages18 Years to 85 Years
SexAll
SponsorUniversity Medical Centre Ljubljana Academic / other
Locations10 sites (Graz and 9 other locations)
Trial IDNCT05467163 on ClinicalTrials.gov

What this trial studies

This clinical trial investigates the effectiveness of conduction system pacing (CSP) compared to biventricular (BiV) pacing in patients with heart failure and symptomatic atrial fibrillation who are undergoing atrioventricular node ablation. The study aims to determine if CSP, which includes His bundle pacing and left bundle branch pacing, provides better clinical and echocardiographic outcomes than BiV pacing. Participants will be randomly assigned to receive either pacing method, and their heart function and symptoms will be monitored over time. The trial focuses on patients with a left ventricular ejection fraction of less than 50% and narrow QRS complexes.

Who should consider this trial

Good fit: Ideal candidates are adults aged 18 to 85 with symptomatic permanent atrial fibrillation, left ventricular ejection fraction less than 50%, and narrow intrinsic QRS complexes.

Not a fit: Patients with pre-existing permanent pacemakers or significant heart valve disease may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved heart function and quality of life for patients with heart failure and atrial fibrillation.

How similar studies have performed: Previous studies have shown that biventricular pacing can reduce mortality and improve symptoms, but the effectiveness of conduction system pacing is still being explored.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Symptomatic permanent atrial fibrillation, refractory to drug therapy or failed catheter ablation
2. Left ventricular ejection fraction \<50%
3. Narrow intrinsic QRS ≤ 120 ms
4. NT-proBNP \> 600 ng/L
5. Patient has provided written informed consent
6. Age between 18 years and 85 years

Exclusion Criteria:

1. Pre-existing permanent pacemaker, implantable cardioverter-defibrillator or cardiac resynchronization device. Patients who had devices implanted that had \<5% of paced beats (i.e., backup pacing) can be enrolled.
2. Life expectancy less than 12 months
3. Severe concomitant non-cardiac disease
4. Pregnancy
5. Recent (\<3 months) myocardial infarction, percutaneous or surgical myocardial revascularization
6. Significant heart valve disease (severe insufficiency or stenosis)
7. Contraindication for oral anticoagulation
8. Mechanical tricuspid valve replacement
9. Unwillingness to participate or lack of availability for follow-up

Where this trial is running

Graz and 9 other locations

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 Heart FailureTachycardia-induced CardiomyopathyAtrial FibrillationHeart failureAtrial fibrillationConduction system pacingHis bundle pacingLeft bundle branch pacing
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.