The Boston Pace Study

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

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

Conditions
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Left Bundle Branch Area Pacing

Intervention / Treatment
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* Device: Left Bundle Branch Area Pacemaker
* Device: Right Ventricular Pacemaker


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age >18 Patients with complete AV block, high-grade AV block with an anticipated ventricular pacing rate of more than 40% Left ventricular ejection fraction of 50% or more. Echocardiogram within the last 3 months Exclusion Criteria: History of systolic dysfunction with LV EF of less than 50% Prior myocardial infarction Obstructive coronary artery disease Severe valvular dysfunction Life expectancy of less than a year Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

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

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | 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 | Measure Description | Time Frame |
| --- | --- | --- |
| Success rate of LBBAP |  | 30 days | 
| All-cause mortality |  | 12 months | 
| Cardiovascular mortality |  | 12 months | 
| 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 | 
| Procedure time |  | 1 day | 
| Fluoroscopy time |  | 1 day | 
| Pacing capture threshold (V) |  | 12 months | 
| R wave amplitude (mV) |  | 12 months | 
| RV lead impedance (ohms) |  | 12 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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left bundle branch, left bundle