The Boston Pace Study

Left Bundle Area Pacing Vs. Right Ventricular Pacing in Patients With Normal Left Ventricular Function -The Boston Pace Study

Right ventricular (RV) pacing can cause left ventricular systolic dysfunction in 10- 20% of patients. Biventricular pacing had previously been shown to prevent left ventricular systolic dysfunction. However, implantation of coronary sinus lead increases procedural risk and can be limited by higher threshold and phrenic nerve capture. HIS pacing has been evaluated as an alternative pacing strategy, but its routine use was limited by difficulty of the procedure, success rate and high pacing threshold.

Left bundle branch area pacing (LBBAP) is a promising physiologic pacing technique that has been proposed as a pacing strategy to prevent pacing induced cardiomyopathy and for treatment of desynchrony in heart failure. LBBAP has been adopted widely and performed routinely on patients with AV block. Currently, it is up to the discretion of the proceduralist whether LBBAP is performed given that there is lack of evidence to guide pacing strategies.

Study Overview

• Status: Active, not recruiting
• Conditions: Left Bundle Branch Area Pacing
• Intervention / Treatment: Device: Left Bundle Branch Area Pacemaker; Device: Right Ventricular Pacemaker

Detailed Description

This pilot trial is a feasibility study that will assess for efficacy, safety and success rate of left bundle branch area pacing. The study will also examine the recruitment rate at 2 major tertiary hospitals.

The study will examine if the use of LBBAP can prevent the occurrence of pacing induced cardiomyopathy (PICM) compared to RV pacing among patients with normal left ventricular function and high-grade AV block.

The investigators hypothesize that the rate of pacing induced cardiomyopathy is lower with LBBAP compared to RV pacing in patients with normal left ventricular function requiring high burden of RV pacing.

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Massachusetts
    • Boston, Massachusetts, United States, 02115
      • Brigham and Women's Hospital
    • Boston, Massachusetts, United States, 02114
      • Massachusetts General Hospital

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Age >18
2. Patients with complete AV block, high-grade AV block with an anticipated ventricular pacing rate of more than 40%
3. Left ventricular ejection fraction of 50% or more.
4. Echocardiogram within the last 3 months

Exclusion Criteria:

1. History of systolic dysfunction with LV EF of less than 50%
2. Prior myocardial infarction
3. Obstructive coronary artery disease
4. Severe valvular dysfunction
5. Life expectancy of less than a year
6. Pregnancy

Study Plan

How is the study designed?

Design Details

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

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Left Bundle Branch Area Pacing	Device: Left Bundle Branch Area Pacemaker; Implantation of Medtronic 3830 lead for left bundle branch area pacing
Active Comparator: Right Ventricular Pacing	Device: Right Ventricular Pacemaker; Implantation of a conventional right ventricular pacemaker lead

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Change in left ventricular ejection fraction (LVEF)	12 months
Change in left ventricular end systolic volume (LVESV)	12 months

Secondary Outcome Measures

Outcome Measure	Time Frame
All-cause mortality	12 months
Fluoroscopy time	1 day
Cardiovascular mortality	12 months
Procedure time	1 day
Success rate of LBBAP	30 days
Rate of heart failure related visit: defined as heart failure hospitalization or emergency room visit or urgent visit requiring intravenous heart failure therapy	12 months
Number of participants with upgrade to cardiac resynchronization therapy	12 months
New York Heart Association Class I-IV (IV is worst)	12 months
Number of participants with occurrence of moderate or severe tricuspid regurgitation on echocardiogram	12 months
Number of participants with occurrence of moderate or severe mitral regurgitation on echocardiogram	12 months
Number of participants with new onset atrial fibrillation	12 months
Kansas City Cardiomyopathy Questionnaire (KCCQ-12) (score of 8-40)	12 months
Paced QRS duration on 12 lead EKG	Evaluated at 1 day, 30 days and 12 months
Pacing percentage	12 months
Complication rate including pneumothorax, cardiac tamponade, infection, and lead revision	12 months
Pacing capture threshold (V)	12 months
R wave amplitude (mV)	12 months
RV lead impedance (ohms)	12 months

Collaborators and Investigators

• Sponsor: Massachusetts General Hospital
• Collaborators: Medtronic

Study record dates

Study Major Dates

• Study Start (Actual): May 1, 2023
• Primary Completion (Estimated): August 31, 2026
• Study Completion (Estimated): August 31, 2026

Study Registration Dates

• First Submitted: April 17, 2023
• First Submitted That Met QC Criteria: May 16, 2023
• First Posted (Actual): May 22, 2023

Study Record Updates

• Last Update Posted (Actual): July 13, 2026
• Last Update Submitted That Met QC Criteria: July 10, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Keywords: left bundle branch; left bundle
• Other Study ID Numbers: 2022P003143

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: Yes