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

NCT06601322 | Recruiting

• 1 other identifier: HM20028599
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Left Branch Bundle Block; RV - Right Ventricular Abnormality

Keywords

Pacemaker; CPET-CMR

Outcome Measures

Primary Outcomes (1)

• Incidence of Pacemaker Atrial (P Wave) Over-Sensed Events

  Incidence of pacemaker atrial (P Wave) over sensing as derived from continuous pacemaker telemetry at optimal programmed atrial sensitivity.

  Day 1: From beginning of CPET-CMR imaging procedure to end of CPET-CMR imaging procedure on study day.

Secondary Outcomes (3)

• Incidence of Pacemaker Atrial (P Wave) Under-Sensed Events

  Day 1: From beginning of CPET-CMR imaging procedure to end of CPET-CMR imaging procedure on study day.

• Left Ventricular Ejection Fraction (%)

  Day 1: From beginning of CPET-CMR imaging procedure to end of CPET-CMR imaging procedure on study day.

• Right Ventricular Ejection Fraction (%)

  Day 1: From beginning of CPET-CMR imaging procedure to end of CPET-CMR imaging procedure on study day.

Other Outcomes (1)

• Slope of VO2 as a Function of Work Rate

  Day 1: From beginning of CPET-CMR imaging procedure to end of CPET-CMR imaging procedure on study day.

Study Arms (3)

No Ventricular Pacing (NVP)

OTHER

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.

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

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

ACTIVE COMPARATOR

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

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

Left Bundle Branch Area Pacing with Anodal Capture (aLBBAP)

EXPERIMENTAL

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.

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

Interventions

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

Following ECG and pacemaker analysis as above for safety, subjects will be fitted with 2 sets of MRI-compatible ECG monitoring systems a BP monitoring system , and a finger-tip pulse gating system. Imaging will be performed on a Magnetom Vida 3 Tesla scanner by trained CRM radiology technologists.

Left Bundle Branch Area Pacing with Anodal Capture (aLBBAP); No Ventricular Pacing (NVP); Non-selective or Selective Left Bundle Branch Area Pacing (nsLBBAP)

Continuous pacemaker telemetry (CPT) OTHER

CPT will be established and supervised by a cardiac electrophysiologist to monitor for evidence of noise or artifact which may lead to inability to appropriately sense native atrial depolarization in DDD mode. Subjects with PM dependence are excluded. If noise is noted during scanning with NVP, then scanning will NOT be performed during P-synchronous pacing and will instead be performed during overdrive pacing at a rate above the patients maximal achieved heart rate with exertion during Phase 1. Thus, there is minimal risk to the subject from PM programming during CPET-CMR.

Left Bundle Branch Area Pacing with Anodal Capture (aLBBAP); No Ventricular Pacing (NVP); Non-selective or Selective Left Bundle Branch Area Pacing (nsLBBAP)

Pacemaker Interrogation and Electrocardiogram (ECG): OTHER

Prior to the CMR study, subjects will undergo baseline interrogation of their dual chamber LBBAP to assess for appropriate device function. Lead capture characteristics will then be assessed with continuous intracardiac electrogram characteristics recorded from the atrial and ventricular lead with simultaneous 12-lead ECG rhythm strip recordings to assess for settings at which the investigators can differentiate aLBBAP, sLBBAP and nsLBBAP. Pacing output will be increased until left bundle branch area pacing with anodal capture is achieved, and then decreased until anodal capture is lost. These programming parameters will be recorded and utilized for Phase 2-3 of the CPET-CMR scan. 12-lead ECG rhythm strips of QRS morphology with each parameter set will be obtained and saved for later analysis.

Left Bundle Branch Area Pacing with Anodal Capture (aLBBAP); No Ventricular Pacing (NVP); Non-selective or Selective Left Bundle Branch Area Pacing (nsLBBAP)

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• presence of dual chamber LBBAP implantation
• presence of anodal capture with bipolar pacing configuration as determined at pacing implant.

You may not qualify if:

• 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.

Sponsors & Collaborators

• Virginia Commonwealth University: lead

Study Sites (1)

Virginia Commonwealth University

Richmond, Virginia, 23298, United States

RECRUITING

MeSH Terms

Conditions

Bundle-Branch Block

Interventions

epicatechin gallate; Exercise Test; Clostridium perfringens epsilon-toxin

Condition Hierarchy (Ancestors)

Heart Block; Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Cardiac Conduction System Disease; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Heart Function Tests; Diagnostic Techniques, Cardiovascular; Diagnostic Techniques and Procedures; Diagnosis; Respiratory Function Tests; Diagnostic Techniques, Respiratory System; Ergometry; Investigative Techniques

Study Officials

• Ajay Pillai

  Virginia Commonwealth University

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Ajay Pillai

CONTACT

(478) 957-2109; ajay.pillai@vcuhealth.org

Melissa Sears

CONTACT

804-828-1601; melissa.sears@vcuhealth.org

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Model Details: Prospective non-randomized controlled pilot study

Study Record Dates

• First Submitted: July 9, 2024
• First Posted: September 19, 2024
• Study Start: August 23, 2024
• Primary Completion: May 1, 2026
• Study Completion: May 1, 2026
• Last Updated: April 16, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)