Pacemaker Testing for Bundle-Branch Block

(FOCUS-Right Trial)

Overseen By Melissa Sears

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Virginia Commonwealth University

Disqualifiers: Chronotropic incompetence, Heart block, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 3

20 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests the safety and practicality of conducting special heart tests on individuals with a specific type of pacemaker, known as a Left Bundle Branch Area Pacemaker (LBBAP), during exercise. The researchers aim to assess how different pacemaker settings impact heart function and exercise capacity. Participants must already have this type of pacemaker and be able to exercise on a special bike. As an unphased trial, this study provides participants the chance to contribute to innovative research that could enhance heart health management for others with similar pacemakers.

Do I need to stop my current medications for this trial?

The trial protocol does not specify whether you need to stop taking your current medications. It is best to consult with the trial coordinators for specific guidance.

What prior data suggests that this pacemaker testing is safe?

Previous studies have shown that left bundle branch area pacing (LBBAP) is quite safe. Research indicates that LBBAP can lower the risk of heart failure associated with other pacing types, such as right ventricular pacing. Increasing clinical evidence supports its safety and stable long-term outcomes.

Though any procedure carries some risks, LBBAP is widely used due to its strong safety record. Some studies have demonstrated that it can improve heart function by reducing electrical and mechanical issues in the heart. Overall, LBBAP is considered a well-tolerated treatment option. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about these pacemaker techniques for treating bundle-branch block because they offer precise pacing options. The Left Bundle Branch Area Pacemaker (LBBAP) allows for targeted pacing of the heart's electrical system, unlike traditional pacemakers, which often pace the heart's ventricles more generally. This method potentially improves heart function both at rest and during exercise. The inclusion of anodal capture in one of the trial arms could offer more efficient stimulation of the heart muscle, which might lead to better outcomes for patients. These innovations could represent significant advances over current treatments, which typically rely on standard right ventricular pacing.

What evidence suggests that this trial's pacemaker programming settings could be effective for improving heart function during exercise?

This trial will compare different pacing methods for patients with bundle-branch block. Research has shown that Left Bundle Branch Area Pacemakers (LBBAP) can be very effective for patients needing rhythm support, especially when other methods are less effective. Studies have found that LBBAP helps the heart beat more regularly and efficiently by improving the coordination of electrical signals and movements. Participants in this trial may receive non-selective or selective LBBAP, or LBBAP with anodal capture, to assess their effects on heart function. Patients with LBBAP have demonstrated better heart function and can exercise more easily compared to those with other pacing methods. Additionally, LBBAP has effectively treated conditions where traditional pacing can weaken the heart. Overall, LBBAP is considered a safe and promising option for improving heart health in certain patients. ^{1 4 5 6 7}

Who Is on the Research Team?

Ajay Pillai

Principal Investigator

Virginia Commonwealth University

Are You a Good Fit for This Trial?

This trial is for patients with a specific heart condition called left bundle branch block who already have pacemakers. They should be able to undergo exercise tests and cardiac imaging safely. People with conditions that make these procedures risky cannot participate.

Inclusion Criteria

Presence of dual chamber LBBAP implantation

Presence of anodal capture with bipolar pacing configuration as determined at pacing implant.

Exclusion Criteria

Known history of chronotropic incompetence

High degree or complete heart block

Inability to undergo MRI or exercise utilizing supine bicycle at target work-load

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Baseline Assessment

Assessment 1 (No Ventricular Pacing) will be performed with no ventricular pacing to assess baseline right and left ventricular function at rest and during exercise.

1 day

1 visit (in-person)

Non-selective or Selective Left Bundle Branch Area Pacing

Phase 2 will assess right and left ventricular function at rest and during exercise with non-selective or selective left bundle branch area pacing.

1 day

1 visit (in-person)

Left Bundle Branch Area Pacing with Anodal Capture

Phase 3 will assess right and left ventricular function at rest and during exercise with left bundle branch area pacing with anodal capture.

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

2-4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Left Bundle Branch Area Pacemaker (LBBAP)

Trial Overview

The FOCUS-Right study is testing how different settings on a patient's pacemaker affect their heart function and ability to exercise. It involves checking the pacemaker, doing an ECG, exercising while inside an MRI machine, and monitoring the pacemaker continuously.

How Is the Trial Designed?

Group I: No Ventricular Pacing (NVP) Experimental Treatment 3 Interventions

Assessment 1 (No Ventricular Pacing) will be performed with no ventricular pacing to assess baseline right and left ventricular function at rest and during exercise.

Group II: Left Bundle Branch Area Pacing with Anodal Capture (aLBBAP) Experimental Treatment 3 Interventions

Phase 3 (Left Bundle Branch Area Pacing with Anodal Capture or aLBBAP) will assess right and left ventricular function at rest and during exercise with left bundle branch area pacing with anodal capture.

Group III: Non-selective or Selective Left Bundle Branch Area Pacing (nsLBBAP) Active Control 3 Interventions

Phase 2 (non-selective or selective Left Bundle Branch Area Pacing or ns/sLBBAP) will assess right and left ventricular function at rest and during exercise with non-selective or selective left bundle branch area pacing

Left Bundle Branch Area Pacemaker (LBBAP) is already approved in United States, European Union, Canada for the following indications:

Approved in United States as Cardiac Pacemaker for:

• Heart block
• Bradycardia
• Cardiac arrhythmias

Approved in European Union as Cardiac Pacemaker for:

• Heart block
• Bradycardia
• Cardiac arrhythmias
• Heart failure

Approved in Canada as Cardiac Pacemaker for:

• Heart block
• Bradycardia
• Cardiac arrhythmias

Who Is Running the Clinical Trial?

Virginia Commonwealth University

Lead Sponsor

Trials

732

Recruited

22,900,000+

Published Research Related to This Trial

Left bundle branch area pacing (LBBAP) is a safe and effective method for correcting complete left bundle branch block (CLBBB) in heart failure patients, with no complications reported in the study of 10 patients.

LBBAP showed superior outcomes compared to biventricular pacing (BIVP), with a higher response rate (100% vs. 63.33%) and greater improvement in electrical synchrony, as indicated by a significantly larger decrease in QRS duration.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The efficacy of left bundle branch area pacing compared with biventricular pacing in patients with heart failure: A matched case-control study. Wang, Y., Gu, K., Qian, Z., et al.[2021]

In a study of 50 bradycardia patients receiving left bundle branch area pacing (LBBAP), the lead tip location significantly influenced left ventricular activation time (LVAT), with shorter LVAT observed when the lead tip was within 2 mm of the left ventricular blood pool.

Paced QRS duration (QRSd) remained consistent across different lead tip locations, indicating that LBBAP can achieve physiological pacing characteristics regardless of the precise lead placement within the interventricular septum.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Computed tomography imaging-identified location and electrocardiographic characteristics of left bundle branch area pacing in bradycardia patients. Chen, K., Liu, X., Hou, X., et al.[2022]

Left bundle branch area pacing (LBBAP) is both feasible and safe for patients with congenital heart disease (CHD), achieving acute success in all 13 CHD patients studied, similar to the 96% success rate in non-CHD patients.

Procedural times and lead parameters were comparable between CHD and non-CHD patients, indicating that LBBAP can be effectively performed in patients with complex heart anatomies without significant complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Left bundle branch area pacing in congenital heart disease. O'Connor, M., Riad, O., Shi, R., et al.[2023]

In a study of 151 patients with symptomatic bradycardia who received left bundle branch area pacing (LBBAP), none developed pacing-induced cardiomyopathy (PICM), indicating that LBBAP is a safe option for patients with preserved left ventricular ejection fraction (LVEF).

For patients with a baseline LVEF below 50%, LBBAP significantly improved heart function, with LVEF increasing from 41.4% to 45.6% and global longitudinal strain (GLS) improving from 12.9% to 15.5% over a median follow-up of 23 months.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Left bundle branch area pacing prevents pacing induced cardiomyopathy in long-term observation. Bednarek, A., Kiełbasa, G., Moskal, P., et al.[2023]

Left bundle branch area pacing (LBBAP) was successfully performed in 82.2% of patients, showing a significant reduction in QRS width, which indicates improved electrical activation of the heart, particularly in patients with left bundle branch block (LBBB).

LBBAP preserved intra-ventricular mechanical synchrony in patients with narrow QRS and right bundle branch block (RBBB), while it improved asynchrony parameters in those with LBBB, suggesting its efficacy in enhancing heart function during routine practice.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Left bundle branch area pacing in patients with baseline narrow, left, or right bundle branch block QRS patterns: insights into electrocardiographic and echocardiographic features. Mirolo, A., Chaumont, C., Auquier, N., et al.[2023]

Left bundle branch area pacing (LBBAP) is a safe and effective long-term pacing method for patients with bradycardia, showing stable pacing thresholds and no procedure-related complications over 12 months in a study of 65 patients.

Patients with pre-existing left bundle branch block experienced the most significant improvement, with a 24 ms narrowing of the paced QRS duration, indicating enhanced cardiac function with LBBAP.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Durability of left bundle branch area pacing. Mehta, NA., Saqi, B., Sabzwari, SRA., et al.[2022]

In a study of 58 patients undergoing left bundle branch area pacing (LBBAP), the procedure was successful in 97% of cases, leading to significant improvements in left ventricular ejection fraction (LVEF) from 52.9% to 56.9% after 3 months (p=0.004).

LBBAP also resulted in marked reductions in both intraventricular and interventricular dyssynchrony, indicating that this pacing method promotes faster and more synchronized biventricular contractions, regardless of the patients' initial heart conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Early effects of left bundle branch area pacing on ventricular activation by speckle tracking echocardiography. Dell'Era, G., Ghiglieno, C., Degiovanni, A., et al.[2023]

Left bundle branch area pacing (LBBAP) is a safe and feasible technique for cardiac pacing, successfully implanted in 96% of 80 patients, with a significant reduction in lead implantation and fluoroscopy times as experience increased.

LBBAP effectively maintains ventricular electrical synchrony, resulting in narrower QRS durations compared to right ventricular septum pacing (RVSP), indicating its potential for better physiological pacing outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A single-centre prospective evaluation of left bundle branch area pacemaker implantation characteristics. Heckman, LIB., Luermans, JGLM., Jastrzębski, M., et al.[2022]

In a study of 29 heart failure patients, left bundle branch pacing (LBBP) was found to significantly improve left ventricular activation speed and mechanical synchrony compared to left ventricular septal pacing (LVSP).

After an average follow-up of 17 months, patients in the LBBP group showed a greater improvement in left ventricular ejection fraction (LVEF) of 26% compared to just 6% in the LVSP group, indicating that LBBP is more effective for resynchronization in heart failure patients.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Resynchronization effects and clinical outcomes during left bundle branch area pacing with and without conduction system capture. Zhang, W., Chen, L., Zhou, X., et al.[2023]

Left bundle branch area pacing (LBBaP) is a safe and effective method for resynchronizing heart function in patients with heart failure and left bundle branch block, showing significant improvements in heart function after 12 months.

Compared to traditional cardiac resynchronization therapy (CRT), LBBaP resulted in shorter operation and X-ray exposure times, and it achieved a narrower QRS complex more quickly, indicating better electrical synchronization of the heart.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Cardiac resynchronization performed by LBBaP-CRT in patients with cardiac insufficiency and left bundle branch block. Zu, L., Wang, Z., Hang, F., et al.[2021]

A new method for selective left bundle branch pacing (LBBP) using continuous low output (2 V / 0.5 ms) was evaluated in 28 patients, showing a high rate of successful left bundle branch capture during the procedure.

The study found that an abrupt shortening of the stimulus-to-peak left ventricular activation time (S-peak LVAT) during low output pacing was highly sensitive (100%) for predicting effective pacing, indicating this method could enhance the safety and efficacy of LBBP.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evaluation of the shortening of the stimulus-to-peak left ventricular activation time at continuous low output to confirm left bundle branch capture. Zhong, J., Zheng, N., Jiang, L.[2022]

In a large study of 2533 patients across 14 European centers, permanent left bundle branch area pacing (LBBAP) showed a high lead implantation success rate of 92.4% for bradyarrhythmia and 82.2% for heart failure, indicating its feasibility as a primary pacing technique.

The study reported a complication rate of 11.7%, with specific complications from the ventricular transseptal route occurring in 8.3% of patients, suggesting that while LBBAP is promising, safety and success rates in heart failure patients need further improvement.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Left bundle branch area pacing outcomes: the multicentre European MELOS study. Jastrzębski, M., Kiełbasa, G., Cano, O., et al.[2022]

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Ischemic cardiomyopathy was observed in 38.1% of patients, and 43.6% presented with left bundle branch block. Figure viewer. Figure 1 Patient ...