Bachmann Bundle Pacing for Prevention of New-Onset Atrial Fibrillation in Patients With Heart Failure

Clinical Efficacy of Bachmann Bundle Pacing on New-Onset Atrial Fibrillation in Patients With Cardiac Insufficiency

This is a multi-center, prospective, single-blind, randomized controlled clinical trial to evaluate the efficacy and safety of Bachmann bundle pacing (BBP) in preventing new-onset atrial fibrillation (AF) in patients with chronic cardiac insufficiency who have indications for cardiac resynchronization therapy with left bundle branch pacing (CRT/LBBP) or implantable cardioverter defibrillator (ICD) implantation.

A total of 110 eligible patients will be randomly assigned 1:1 to the BBP group or the traditional right atrial appendage (RAA) pacing group. All patients will receive guideline-directed medical therapy (GDMT) for at least 3 months and standardized follow-up for 12 months after device implantation. The primary endpoint is the incidence of new-onset AF within 12 months after implantation. Secondary endpoints include time to first new-onset AF, procedural success rate, changes in cardiac function parameters, and incidence of adverse events. This study aims to provide high-level evidence-based medical evidence for BBP as a new atrial pacing strategy to prevent AF in heart failure patients.

Study Overview

• Status: Not yet recruiting
• Conditions: Heart Failure; Atrial Fibrillation (AF); Cardiac Insufficiency
• Intervention / Treatment: Procedure: Bachmann Bundle Pacing; Procedure: Right Atrial Appendage Pacing

Detailed Description

Background Chronic heart failure (HF) is a prevalent and prognostically poor cardiovascular disorder, with atrial fibrillation (AF) being the most common arrhythmia comorbid with HF. The bidirectional interaction between HF and AF forms a vicious cycle, significantly elevating the risks of mortality, hospitalization, and stroke in affected patients. Epidemiological data indicate that the cumulative incidence of AF following pacemaker implantation reaches 30-40%, a rate markedly higher than that in the general population without pacemaker implantation.

Traditional right atrial appendage (RAA) pacing, the most widely used clinical atrial pacing approach, induces prolonged interatrial conduction, asynchronous atrial contraction, and hemodynamic perturbations, which predispose patients to AF. The Bachmann bundle represents the most physiological atrial pacing site; pacing in this region achieves synchronous activation of the left and right atria, producing a narrower P wave compared with sinus rhythm and traditional RAA pacing. While prior studies have suggested that Bachmann bundle pacing (BBP) may reduce the recurrence and progression of atrial arrhythmias, there remains a paucity of prospective randomized controlled trials investigating the efficacy of BBP in preventing new-onset AF in HF patients undergoing cardiac resynchronization therapy with left bundle branch pacing (CRT/LBBP) or implantable cardioverter defibrillator (ICD) implantation.

Study Objectives The primary objective of this study is to determine whether BBP reduces the incidence of new-onset AF within 12 months of device implantation, compared with traditional RAA pacing, in HF patients with indications for CRT/LBBP or ICD implantation. Secondary objectives include evaluating the impact of BBP on the time to first new-onset AF, procedural safety, cardiac function parameters, electrophysiological indices, and clinical adverse events (including HF rehospitalization, all-cause death, and stroke) during the 12-month follow-up period.

Study Procedures

1. Screening and Baseline Assessment Eligible patients are identified per predefined inclusion and exclusion criteria. Following written informed consent, baseline data are collected, including demographic characteristics, medical history, 12-lead electrocardiogram (ECG), 24-hour Holter monitoring, transthoracic echocardiography, New York Heart Association (NYHA) functional classification, 6-minute walk test results, and N-terminal pro-brain natriuretic peptide (NT-proBNP) levels.
2. Randomization Patients are stratified by implant device type (CRT/LBBP or ICD) and randomized in a 1:1 ratio to the BBP group or the RAA pacing group via a central randomization system.
3. Intervention Patients in the BBP group undergo atrial lead implantation at the Bachmann bundle region, identified via anatomical localization and intracardiac electrogram recording. Successful BBP is defined by characteristic ECG changes: a positive P wave in leads I, II, III, and aVF; a biphasic or negative P wave in lead V1; a P wave duration narrowed by >10 ms compared with baseline (in patients with pre-existing interatrial block); and documentation of the Bachmann bundle potential. If BBP implantation fails, the patient is immediately converted to RAA pacing, with the cause of failure recorded in detail. Intraoperative pacing parameters (threshold, sensing, impedance) are monitored in both groups.
4. Follow-up All patients undergo follow-up assessments at 1 week, 3 months, 6 months, 9 months, and 12 months post-implantation. Follow-up evaluations include ECG, 24-hour Holter monitoring, pacemaker programming, echocardiography, NYHA classification reassessment, 6-minute walk test, NT-proBNP measurement, medication adjustment tracking, and adverse event reporting.
5. Statistical Analysis All data are analyzed in accordance with the intention-to-treat (ITT) principle. The primary endpoint is compared using analysis of covariance, and the time to first new-onset AF is evaluated via the Kaplan-Meier method with log-rank testing. Continuous variables are compared using the t-test or Wilcoxon rank-sum test, while categorical variables are analyzed with the chi-square test or Fisher's exact test. A two-sided P value < 0.05 is considered statistically significant.

• Study Type: Interventional
• Enrollment (Estimated): 140
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Xiaohan Fan, MD, PhD; Phone Number: +8615611980322; Email: fanxiaohan@fuwaihospital.org

Study Locations

• China
  • Beijing Municipality
    • Beijing, Beijing Municipality, China, 100037
      • Fuwai Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Aged between 18 and 70 years old;
2. Diagnosis of chronic cardiac insufficiency according to current guidelines, and received guideline-directed medical therapy (GDMT) for at least 3 months;
3. Have indications for CRT/LBBP or ICD implantation, and expected atrial pacing ratio > 20%, including: Sinus rhythm, QRS duration > 120ms, LBBB, LVEF ≤ 35% with symptomatic heart failure; Sinus rhythm, QRS duration ≥ 150ms, non-LBBB, LVEF ≤ 35% with symptomatic heart failure; Sinus rhythm, QRS duration > 120ms, LBBB, LVEF 36%-50% with symptomatic heart failure; Symptomatic heart failure with LVEF ≤ 50% and expected ventricular pacing ratio > 20%; Symptomatic heart failure with LVEF ≤ 50% requiring ICD implantation for primary or secondary sudden death prevention, with atrial pacing indication due to sinus bradycardia or expected atrial pacing ratio > 20%;
4. Patients with pacing-induced cardiomyopathy requiring upgrade therapy, in sinus rhythm, and requiring reimplantation of atrial lead;
5. Signed written informed consent form approved by the ethics committee.

Exclusion Criteria:

1. Expected survival time less than 12 months;
2. Status after mechanical tricuspid valve replacement, or congenital heart disease (including dextrocardia, transposition of great arteries, single left persistent superior vena cava);
3. Previous history of atrial fibrillation;
4. Previous cardiac surgery, or requiring surgical treatment for severe structural heart disease within 1 year;
5. Pregnancy, planned pregnancy, or heart transplantation;
6. Patient refusal to participate in the study.

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Bachmann Bundle Pacing; Patients receive atrial lead implantation at the Bachmann bundle region, identified by anatomical localization and intracardiac electrogram. Successful BBP is defined by characteristic ECG changes (positive P wave in I/II/III/aVF, biphasic/negative P wave in V1, narrowed P wave duration) and recording of Bachmann bundle potential. If BBP fails, patients are converted to RAA pacing, with failure reasons documented.	Procedure: Bachmann Bundle Pacing; A minimally invasive endocardial pacing procedure where an atrial lead is placed at the Bachmann bundle region (located at the junction of the right atrium and left atrial appendage) under fluoroscopic and intracardiac electrogram guidance. Successful implantation is confirmed by characteristic ECG changes (positive P wave in leads I/II/III/aVF, biphasic/negative P wave in V1, P wave duration reduction >10 ms in patients with interatrial block) and recording of the Bachmann bundle potential.; Other Names: BBP
Active Comparator: Traditional Right Atrial Appendage Pacing; Patients receive conventional atrial lead implantation in the right atrial appendage (RAA), the standard clinical atrial pacing method. Intraoperative pacing parameters (threshold, sensing, impedance) are monitored identically to the experimental group to ensure normal pacing function. All patients continue guideline-directed medical therapy for heart failure throughout the study.	Procedure: Right Atrial Appendage Pacing; The standard clinical atrial pacing procedure where an atrial lead is implanted in the right atrial appendage via transvenous access, guided by fluoroscopy. Pacing parameters (threshold, sensing, impedance) are optimized intraoperatively to ensure stable atrial capture, consistent with current clinical practice guidelines for cardiac pacing in heart failure patients.; Other Names: RAA Pacing

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of New-Onset Atrial Fibrillation	The proportion of patients who develop new-onset atrial fibrillation (AF) confirmed by 12-lead ECG or 24-hour Holter monitoring within 12 months after cardiac pacing device implantation. New-onset AF is defined as the first documentation of AF with a duration ≥30 seconds in patients with no prior history of AF or paroxysmal AF (documented ≥3 months before enrollment).	12 months after device implantation
Time to Onset of New-Onset Atrial Fibrillation Post-Device Implantation	Time from CRT/LBBP or ICD implantation to the first documentation of new-onset atrial fibrillation (AF) confirmed by 12-lead ECG or 24-hour Holter monitoring, with AF defined as an episode lasting ≥30 seconds. Time is recorded in days and analyzed using Kaplan-Meier survival methods.	Up to 12 months after device implantation

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Immediate Success Rate of Bachmann Bundle Pacing and Perioperative Complication Rate	Immediate success of Bachmann bundle pacing is defined as stable lead placement with successful atrial capture and characteristic ECG changes intraoperatively; perioperative complications (occurring within 30 days post-surgery) include lead dislodgement, pneumothorax, cardiac tamponade, and pocket hematoma, with incidence calculated as the proportion of patients with at least one complication in each group.	Intraoperatively (success rate) and 30 days post-implantation (perioperative complications)
Absolute and percentage change in left atrial diameter/volume index from baseline to 12 months	Absolute and percentage changes in left atrial diameter (mm) and left atrial volume index (mL/m²) measured by transthoracic echocardiography at 12 months post-implantation compared with baseline.	Baseline and 12 months after device implantation
Change in mitral/tricuspid regurgitation grade from baseline to 12 months	Change in mitral and tricuspid regurgitation grade (graded 0-IV) measured by transthoracic echocardiography at 12 months post-implantation compared with baseline.	Baseline and 12 months after device implantation
Absolute change in left ventricular end-diastolic diameter (LVEDD) from baseline to 12 months	Absolute change in LVEDD (mm) measured by transthoracic echocardiography at 12 months post-implantation compared with baseline.	Baseline and 12 months after device implantation
Absolute change in left ventricular end-systolic volume (LVESV) from baseline to 12 months	Absolute change in LVESV (mL) measured by transthoracic echocardiography at 12 months post-implantation compared with baseline.	Baseline and 12 months after device implantation
Change in New York Heart Association (NYHA) functional class from baseline to 12 months	Change in NYHA functional class (graded I-IV) at 12 months post-implantation compared with baseline.	Baseline and 12 months after device implantation
Absolute change in 6-minute walk test (6MWT) distance from baseline to 12 months	Absolute change in 6MWT distance (meters) at 12 months post-implantation compared with baseline	Baseline and 12 months after device implantation
Absolute change in plasma NT-ProBNP level from baseline to 12 months	Absolute change in plasma NT-ProBNP level (pg/mL) measured by chemiluminescent immunoassay at 12 months post-implantation compared with baseline.	Baseline and 12 months after device implantation
Comparison of P-wave duration from baseline to 12 months	Comparison of P-wave duration (ms) in the supine position (mean of 3 consecutive readings) between baseline and 12 months post-implantation	Baseline and 12 months after device implantation
Comparison of P-wave amplitude from baseline to 12 months	Comparison of P-wave amplitude (mV) in the supine position (mean of 3 consecutive readings) between baseline and 12 months post-implantation	Baseline and 12 months after device implantation
Comparison of P-wave vector from baseline to 12 months	Comparison of P-wave vector in the supine position between baseline and 12 months post-implantation.	Baseline and 12 months after device implantation
Prevalence of interatrial block at baseline and 12 months	Prevalence of interatrial block (diagnosed by ECG criteria) in the supine position between baseline and 12 months post-implantation	Baseline and 12 months after device implantation
Comparison of ventricular pacing threshold from baseline to 12 months	Comparison of ventricular pacing threshold (V) in the supine position (mean of 3 consecutive readings) between baseline and 12 months post-implantation.	Baseline and 12 months after device implantation
Comparison of sensing threshold from baseline to 12 months	Comparison of sensing threshold (mV) in the supine position (mean of 3 consecutive readings) between baseline and 12 months post-implantation	Baseline and 12 months after device implantation
Comparison of lead impedance from baseline to 12 months	Comparison of lead impedance (Ω) in the supine position (mean of 3 consecutive readings) between baseline and 12 months post-implantation.	Baseline and 12 months after device implantation
Incidence of Procedure Complications Within 12 Months Post-Implantation	Cumulative incidence of long-term surgical complications (including lead fracture, chronic pocket infection, lead dislodgement, and cardiac perforation) within 12 months post-implantation, with complications adjudicated by an independent committee using VARC-3 criteria for severity and causality.	12 months after device implantation
Incidence of Heart Failure Rehospitalization, All-Cause Death, and Stroke Within 12 Months	Cumulative incidence of heart failure rehospitalization (unplanned admission for worsening HF), all-cause mortality, and ischemic/hemorrhagic stroke within 12 months post-implantation. All events are documented via medical records and confirmed by the study team.	12 months after device implantation

Collaborators and Investigators

• Sponsor: Fu Wai Hospital, Beijing, China

Publications and helpful links

General Publications

• Bailin SJ, Adler S, Giudici M. Prevention of chronic atrial fibrillation by pacing in the region of Bachmann's bundle: results of a multicenter randomized trial. J Cardiovasc Electrophysiol. 2001 Aug;12(8):912-7. doi: 10.1046/j.1540-8167.2001.00912.x.
• Subramanian M, Yalagudri S, Saggu D, Singh J, Bootla D, Krishnamoorthy P, Chennapragda S, Narasimhan C. Electrogram-guided Bachmann bundle area pacing to correct interatrial block: Initial experience, safety, and feasibility. Heart Rhythm. 2025 Apr;22(4):1064-1070. doi: 10.1016/j.hrthm.2024.08.024. Epub 2024 Aug 20.
• Lustgarten DL, Habel N, Sanchez-Quintana D, Winget J, Correa de Sa D, Lobel R, Thompson N, Infeld M, Meyer M. Bachmann bundle pacing. Heart Rhythm. 2024 Sep;21(9):1711-1717. doi: 10.1016/j.hrthm.2024.03.1786. Epub 2024 Mar 27. No abstract available.
• Infeld M, Nicoli CD, Meagher S, Tompkins BJ, Wayne S, Irvine B, Betageri O, Habel N, Till S, Lobel J, Meyer M, Lustgarten DL. Clinical impact of Bachmann's bundle pacing defined by electrocardiographic criteria on atrial arrhythmia outcomes. Europace. 2022 Oct 13;24(9):1460-1468. doi: 10.1093/europace/euac029.

Study record dates

Study Major Dates

• Study Start (Estimated): April 1, 2026
• Primary Completion (Estimated): April 1, 2028
• Study Completion (Estimated): April 1, 2028

Study Registration Dates

• First Submitted: March 25, 2026
• First Submitted That Met QC Criteria: April 16, 2026
• First Posted (Actual): April 23, 2026

Study Record Updates

• Last Update Posted (Actual): April 23, 2026
• Last Update Submitted That Met QC Criteria: April 16, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Cardiac Resynchronization Therapy; Implantable Cardioverter Defibrillator; Physiological Pacing; New-Onset Atrial Fibrillation; Bachmann Bundle Pacing; Right Atrial Appendage Pacing
• Additional Relevant MeSH Terms: Cardiovascular Diseases; Pathologic Processes; Heart Diseases; Arrhythmias, Cardiac; Pathological Conditions, Signs and Symptoms; Heart Failure; Atrial Fibrillation; 4-boronic acid benzophenone
• Other Study ID Numbers: 2025-2951

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: The decision to share individual participant data (IPD) is currently undecided and will be reassessed upon completion of the study. Considerations will include compliance with Chinese regulations on medical data privacy, ethical approval requirements for data sharing, and the need to protect participants' confidential health information. A formal IPD sharing plan will be developed if deemed appropriate post-study, in accordance with international clinical research standards.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No