Functional Outcomes in CondUction System Pacing and Right Ventricular Synchrony (FOCUS-Right)

Virginia Commonwealth University (VCU)

Status: Enrolling

Conditions: RV - Right Ventricular Abnormality; Left Branch Bundle Block

Treatments: Other: Cardiopulmonary Exercise Test (CPET) and Exercise Stress Cardiac Magnetic Resonance (ExeCMR; Other: Continuous pacemaker telemetry (CPT); Other: Pacemaker Interrogation and Electrocardiogram (ECG):

Study type: Interventional

Funder types: Other

Identifiers

NCT06601322

HM20028599

Details and patient eligibility

About

The goal of this prospective single center clinical trial is to evaluate the safety and feasibility of performing simultaneous exercise stress cardiac magnetic resonance (CPET-CMR) and cardiopulmonary exercise testing in patients with pre-existing left bundle branch area pacemakers (LBBAP) programmed to an atrial sensing mode. Measurements of right ventricular, left ventricular function, and exercise capacity will be obtained at various LBBAP programming parameters at rest and during low intensity exercise. The main aims of the study are:

• Demonstrate the safety and feasibility of performing CPET-CMR in patients with pre-existing LBBAP programmed to P-synchronous ventricular pacing mode.
• Generate preliminary data evaluating differences in RV function, LV function, and exercise capacity during various pacemaker programming settings.

Full description

Conduction system pacing, namely left bundle branch area pacing (LBBAP) represents an important pacing modality introduced to avoid the deleterious effects of non-physiologic ventricular activation during chronic right ventricular pacing and /or left bundle branch block (LBBBP). Previous studies have demonstrated that LBBAP exhibits similar or superior left ventricular resynchronization compared to conventional treatment modalities, the impact of this novel pacing strategy on the right ventricle has not yet been addressed. This study aims to demonstrate the safety and feasibility of assessing LBBAP performance with a focus on right ventricular function in a novel way utilizing Cardiopulmonary Exercise Testing and Exercise Stress Cardiac Magnetic Resonance.

The investigators plan a 1-day prospective non-randomized controlled pilot study in which up to 20 subjects with left bundle branch area pacemakers with evidence of output dependent anodal capture will undergo low intensity exercise CPET-CMR at three different LBBAP settings (underlying rhythm, non-selective left bundle pacing, non-selective left bundle pacing with anodal stimulation).

Enrollment: 20 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

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 tolerate NVP during initial device interrogation
• pregnancy
• inability to undergo MRI or exercise utilizing supine bicycle at target work-load
• presence of MRI unsafe pacemaker components.

Trial design

Primary purpose: Treatment

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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20 participants in 3 patient groups

No Ventricular Pacing (NVP)

Other group

Description:

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.

Treatment:

Other: Pacemaker Interrogation and Electrocardiogram (ECG):

Other: Continuous pacemaker telemetry (CPT)

Other: Cardiopulmonary Exercise Test (CPET) and Exercise Stress Cardiac Magnetic Resonance (ExeCMR

Non-selective or Selective Left Bundle Branch Area Pacing (nsLBBAP)

Active Comparator group

Description:

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

Treatment:

Other: Pacemaker Interrogation and Electrocardiogram (ECG):

Other: Continuous pacemaker telemetry (CPT)

Other: Cardiopulmonary Exercise Test (CPET) and Exercise Stress Cardiac Magnetic Resonance (ExeCMR

Left Bundle Branch Area Pacing with Anodal Capture (aLBBAP)

Experimental group

Description:

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.

Treatment:

Other: Pacemaker Interrogation and Electrocardiogram (ECG):

Other: Continuous pacemaker telemetry (CPT)

Other: Cardiopulmonary Exercise Test (CPET) and Exercise Stress Cardiac Magnetic Resonance (ExeCMR