Bundle Branch Pacing to Preserve Ejection Fraction in Atrial Fibrillation Trial (BEAT)

August 6, 2026 updated by: Poitiers University Hospital

Left Bundle Branch Area Pacing Versus Conventional Right Ventricular Pacing as Initial Strategy for Patients With Permanent Atrial Fibrillation and Preserved Left Ventricular Ejection Fraction Requiring Cardiac Pacing: an Open-label, Multicenter, Randomized Clinical Trial. - the BEAT Study -

The goal of this clinical trial is to learn whether left bundle branch area pacing, a technique designed to activate the heart's natural electrical conduction system, is better than conventional right ventricular pacing in adults with permanent atrial fibrillation, preserved heart pumping function, and a need for a pacemaker.

The main questions it aims to answer are:

Does left bundle branch area pacing reduce the risk of death, unplanned hospitalization for heart failure, or the need to replace the initial pacing system with biventricular pacing over 2 years? Does it better preserve heart function and quality of life, without increasing pacemaker-related complications?

Researchers will compare left bundle branch area pacing with conventional right ventricular pacing. A total of 642 participants will be randomly assigned to receive one of these two pacing strategies.

Participants will:

Have a single-chamber pacemaker implanted using either left bundle branch area pacing or conventional right ventricular pacing Undergo electrocardiograms, echocardiograms, and pacemaker checks during 2 years of follow-up Attend follow-up visits approximately 2, 12, and 24 months after implantation Be contacted by telephone approximately 6 and 18 months after implantation Complete questionnaires about their health and quality of life at the beginning and end of the study

Study Overview

Detailed Description

The BEAT Study is a prospective, multicenter, open-label, randomized controlled clinical trial designed to compare left bundle branch area pacing with conventional right ventricular pacing as the initial pacing strategy in adults with permanent atrial fibrillation, preserved left ventricular ejection fraction, and an indication for permanent ventricular pacing.

Conventional right ventricular pacing is the standard pacing strategy for patients with bradycardia. The ventricular lead is usually positioned at the right ventricular apex or septum. Although this approach is well established, prolonged right ventricular pacing produces a non-physiological pattern of ventricular electrical activation. The resulting electrical and mechanical dyssynchrony may progressively impair left ventricular function and lead to pacing-induced cardiomyopathy, heart failure, hospitalization, and the need for a subsequent procedure to upgrade the pacing system to biventricular pacing.

Patients with permanent atrial fibrillation who require a pacemaker may be particularly exposed to these complications because they generally have a high burden of ventricular pacing. This applies both to patients with slow atrial fibrillation and to those undergoing atrioventricular node ablation for rapid atrial fibrillation. Although these patients may have preserved left ventricular systolic function at the time of pacemaker implantation, repeated non-physiological ventricular activation could contribute to subsequent deterioration in cardiac function.

Left bundle branch area pacing is a conduction-system pacing technique in which the ventricular lead is advanced through the interventricular septum to stimulate the left bundle branch or the surrounding conduction tissue. By recruiting the heart's intrinsic conduction system, this approach is intended to produce more physiological and synchronous ventricular activation than conventional right ventricular pacing. It may therefore preserve left ventricular function and reduce the clinical consequences associated with long-term ventricular pacing.

Evidence supporting left bundle branch area pacing has increased, particularly in patients with impaired left ventricular function or an indication for cardiac resynchronization. However, long-term randomized evidence remains limited in patients with permanent atrial fibrillation, preserved left ventricular ejection fraction, and an expected high ventricular pacing burden. In particular, the effect of the initial pacing strategy on major clinical events in this population has not been adequately established.

The study hypothesis is that left bundle branch area pacing, compared with conventional right ventricular pacing, will reduce clinically important adverse events over 2 years by limiting pacing-related ventricular dyssynchrony and preventing deterioration in left ventricular function.

A total of 642 participants will be enrolled and randomly assigned in a 1:1 ratio to one of two pacing strategies:

Left bundle branch area pacing: implantation of a single-chamber pacemaker with the ventricular lead positioned within the left bundle branch area through the interventricular septum to capture the cardiac conduction system.

Conventional right ventricular pacing: implantation of a single-chamber pacemaker with the ventricular lead positioned at the right ventricular apex or right ventricular septum.

Randomization will be stratified by participating center and by the indication for pacing: rapid permanent atrial fibrillation requiring atrioventricular node ablation or slow permanent atrial fibrillation. Because the implantation techniques are different and identifiable to the treating clinicians, the study is open label.

Participants will be followed for 24 months after pacemaker implantation. Study assessments will include clinical evaluation, pacemaker interrogation, 12-lead electrocardiography, echocardiography, collection of hospitalizations and cardiac reinterventions, assessment of adverse events, and evaluation of health-related quality of life. Follow-up will include clinical visits approximately 2, 12, and 24 months after implantation and telephone contacts approximately 6 and 18 months after implantation.

Echocardiography will be performed at baseline and at the end of the 2-year follow-up to evaluate changes in left ventricular systolic function and ventricular volumes. Pacemaker interrogation will be used to document device function and the proportion of ventricular pacing. Quality of life will be assessed using the Short Form-36 Health Survey and the Kansas City Cardiomyopathy Questionnaire.

The principal comparison will assess whether left bundle branch area pacing improves the proportion of participants who remain free from all-cause death, unplanned hospitalization for heart failure, and upgrade to biventricular pacing at 2 years. Additional analyses will examine cardiac function, individual clinical events, cardiac reinterventions, device- and procedure-related complications, and changes in quality of life. Unplanned heart failure hospitalizations and upgrades to biventricular pacing will be reviewed by an independent adjudication committee.

The primary analysis will follow the intention-to-treat principle. The study is intended to determine whether a physiological pacing strategy should replace conventional right ventricular pacing as the preferred initial approach for patients with permanent atrial fibrillation, preserved left ventricular function, and a substantial anticipated requirement for ventricular pacing.

Study Type

Interventional

Enrollment (Estimated)

642

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact Backup

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Age ≥ 18 years and <90 years
  • Atrial fibrillation requiring ventricular pacing because of

    1. rapid atrial fibrillation requiring atrioventricular node ablation; or
    2. slow atrial fibrillation i.e. ≤ 50 bpm on admission ECG).
  • Left ventricular ejection fraction ≥50%.
  • Affiliated person or beneficiary of the French social security scheme
  • Having given their informed consent.

Exclusion Criteria:

  • Indication for an implantable cardioverter defibrillator.
  • Presence of a mechanical tricuspid valve
  • Any prior attempt at implantation of an implantable cardioverter defibrillator, cardiac resynchronization therapy or LBBA pacing
  • Glomerular filtration rate <40 mL/min/1,73m2 with CKD-EPI formula
  • Chronic respiratory failure
  • Serious medical condition with life expectancy of <2 years
  • Pregnant or breastfeeding women, women of childbearing age who do not have effective contraception (hormonal/mechanical: per os, injectable, transcutaneous, implantable, intrauterine device, or surgical: tubal ligation, hysterectomy, total oophorectomy)
  • Persons benefiting from enhanced protection, i.e. minors, persons deprived of their liberty by a judicial or administrative decision, persons staying in a health or social institution, adults under legal protection, and finally patients in emergency situations

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: LBBA pacing
The LBBA pacing group will be composed of patients randomized to receive a single chamber pacemaker with a ventricular lead implanted in the LBBA of the cardiac conduction system through the interventricular septum.
The LBBA pacing group will be composed of patients randomized to receive a single chamber pacemaker with a ventricular lead implanted in the LBBA of the cardiac conduction system through the interventricular septum.
Active Comparator: Conventional pacing
The conventional pacing group will be composed of patients randomized to receive a single chamber pacemaker with a ventricular lead implanted either at the apex or the septum of the right ventricle.
The conventional pacing group will be composed of patients randomized to receive a single chamber pacemaker with a ventricular lead implanted either at the apex or the septum of the right ventricle.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Proportion of post-implantation adverse events
Time Frame: At two years
proportion of post-implantation adverse events, combining all-cause mortality, unplanned hospitalization related to heart failure, and upgrade to biventricular pacing.
At two years

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Left ventricular ejection fraction
Time Frame: At 2 years post-implantation.
Left ventricular ejection fraction assessed with echocardiography
At 2 years post-implantation.
Left ventricular end-systolic volume
Time Frame: At 2 years post-implantation
Left ventricular end-systolic volume assessed with echocardiography
At 2 years post-implantation
Time to composite outcome
Time Frame: Through study completion, an average of 2 years
Time to the first event between death, unplanned hospitalization related to heart failure, and upgrade to biventricular during the 2-year follow-up period
Through study completion, an average of 2 years
Unplanned hospitalization related to heart failure
Time Frame: During the 2-year follow-up perio
Time to unplanned hospitalization for heart failure
During the 2-year follow-up perio
All-cause mortality
Time Frame: During the 2-year follow-up period
Time to all-cause death
During the 2-year follow-up period
Upgrade to biventricular pacing
Time Frame: During the 2-year follow-up period
Time to upgrade to biventricular
During the 2-year follow-up period
Complications
Time Frame: During the 2-year follow-up period
Proportions of pocket hematoma, pneumothorax, lead dislodgment, pacing threshold elevation, pericardial effusion, pocket/wound infection, systemic infection, lead fracture, diaphragmatic stimulation, or pacemaker syndrome
During the 2-year follow-up period
Cardiac reintervention
Time Frame: During the 2-year follow-up period
Time to cardiac reintervention for upgrade to biventricular pacing or due to a complication
During the 2-year follow-up period
Quality of life : Short Form 36 Questionnaire score
Time Frame: Evolution between baseline and 2 years post-implantation
Evolution at the Short Form 36 Questionnaire score. Minimum score: 0; Maximum score: 100; A higher score indicates better health-related quality of life.
Evolution between baseline and 2 years post-implantation
Quality of life : Kansas City Cardiomyopathy Questionnaire score
Time Frame: Evolution between baseline and 2 years post-implantation
Evolution at the Kansas City Cardiomyopathy Questionnaire score. Minimum: 0 - worst possible heart-failure-related health status; Maximum: 100 - best possible health status, with fewer symptoms and limitations
Evolution between baseline and 2 years post-implantation

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

September 15, 2026

Primary Completion (Estimated)

August 14, 2028

Study Completion (Estimated)

August 14, 2030

Study Registration Dates

First Submitted

August 2, 2026

First Submitted That Met QC Criteria

August 6, 2026

First Posted (Actual)

August 12, 2026

Study Record Updates

Last Update Posted (Actual)

August 12, 2026

Last Update Submitted That Met QC Criteria

August 6, 2026

Last Verified

August 1, 2026

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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