An interventional study of His/LBBP and BiVP in Heart Failure, Heart Failure With Reduced Ejection Fraction and AV Block, sponsored by Baylor College of Medicine. Recruiting at 71 sites in 2 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-10-02.
Sponsored by Baylor College of Medicine · Not applicable, Interventional, and Treatment
The investigators aim to prospectively test the comparative effectiveness of His or Left bundle branch pacing in relation to patient centered outcomes (quality of life, physical activity, heart failure hospitalization, mortality) and comparative safety in relation to device-related complications and re-interventions (e.g., lead dislodgement, infection) relative to standard of care biventricular pacing in patients with heart failure due to left ventricular systolic dysfunction (LVEF≤50%) and with either a wide QRS (≥130 ms) or with/anticipated >40% pacing who are already receiving current standard heart failure pharmacological therapy.
In this prospective, randomized, multi-center clinical trial, the investigators aim to prospectively evaluate the comparative effectiveness His or Left bundle branch pacing (His/LBBP) vs. biventricular pacing (BiVP) in patients with heart failure due to left ventricular systolic dysfunction (LVEF≤50%) and with either a wide QRS (≥130 ms) or with/anticipated >40% pacing who are already receiving current standard heart failure pharmacological therapy by assessing all cause death and heart failure hospitalization at the end of the study.
Additional formal secondary objectives include evaluation disease-specific quality and psychological adjustment changes at 1 year after device implant and evaluation of a composite of death of any cause or heart failure hospitalization or more >15% increase in the left ventricular end-systolic volume index at the end of the study.
Exclusion Criteria:
Patients with LVEF≤35% at entry will receive a His/LBB defibrillator which includes implantation of three leads, an endocardial right atrial lead, an endocardial right ventricular ICD lead, and an endocardial His-bundle or left bundle branch pacing lead directly pacing the intrinsic conduction system. Patients with LVEF 36-50% at entry will receive His/LBB pacemaker which includes implantation of two leads, an endocardial right atrial lead, and an endocardial His-bundle or left bundle branch pacing lead directly pacing the intrinsic conduction system.
Device: His/LBBP
Patients with LVEF≤35% at entry will receive a BiV defibrillator which includes implantation of three leads, an endocardial right atrial lead, an endocardial right ventricular ICD lead, and and an epicardial left ventricular lead implanted in a branch of the coronary sinus. Patients with LVEF 36-50% at entry will receive BiV pacemaker which includes implantation of three leads, an endocardial right atrial lead, an endocardial right ventricular pacing lead, and and an epicardial left ventricular lead implanted in a branch of the coronary sinus.
Device: BiVP
Pacing at the level His-Bundle or left bundle branch is used to correct the underlying conduction abnormality, resulting in a faster and more homogeneous activation of the heart pacing directly via the intrinsic conduction system of the heart accompanied by a right atrial endocardial lead and a right ventricular defibrillator endocardial lead for LVEF≤35% and by a right atrial endocardial lead for LVEF 36-50%.
Biventricular pacing has been shown to improve outcomes by delivering synchronized electrical stimuli to the right and left ventricles utilizing an an endocardial right atrial lead, an endocardial right ventricular lead, and an epicardial left ventricular lead implanted in a branch of the coronary sinus. For LVEF≤35% a biventricular pacemaker-defibrillator will be implanted while for LVEF 36-50% a biventricular pacemaker will be implanted.
A combined clinical endpoint of all-cause mortality and hospitalization for heart failure
The primary efficacy outcome will be described using Kaplan-Meier freedom from event curves over time, with event-free survival compared between assigned treatment arms using a logrank test, stratified by levels of the two factors (LVEF (≤35% vs. 36 to 50%) and conduction abnormality (LBBB vs non-LBBB)) used for randomization.
Time frame: 5.5 years
Assess change in Kansas City Cardiomyopathy Questionnaire-12 (KCCQ-12) at 12 months
Assess change in Kansas City Cardiomyopathy Questionnaire-12 (KCCQ-12) item score measured before and at 12 months after implant.
Time frame: 12 months
Change in composite endpoint comprised of death, first hospitalization for worsening HF and left ventricular end systolic volume index (LVESVi) at 5.5 years
Secondary endpoint measured from all cause death, first hospitalization for heart failure and echocardiography on left ventricular end-systolic volume index (LVESVi) in the His/LBBP vs. BIV-BiVP arm
Time frame: 5.5 years
Composite of cardiovascular death or heart transplant or durable left ventricular assist device or more > 15% increase in the LVESVi or change in KCCQ-12 at the end of the study using win ratio
Secondary endpoint measured from cardiovascular death or heart transplant or durable left ventricular assist device or more \> 15% increase in the LVESVi or change in KCCQ-12 at the end of the study using win ratio
Time frame: 5.5 years
Death from any cause at 5.5 years
Secondary endpoint measured from all cause death
Time frame: 5.5 years
Death from any cardiovascular cause at 5.5 years
Secondary endpoint measured from death due to cardiovascular causes
Time frame: 5.5 years
Hospitalization for heart failure at 5.5 years
Secondary endpoint measured from first hospitalization for heart failure
Time frame: 5.5 years
Cardiovascular hospitalization at 5.5 years
Secondary endpoint measured from first hospitalization for cardiovascular disease
Time frame: 5.5 years
Total HF hospitalizations
Total number of HF hospitalizations
Time frame: 5.5 years
Composite of cardiovascular death or first HF hospitalization
Secondary endpoint measured from cardiovascular death, first hospitalization for heart failure
Time frame: 5.5 years
Composite cardiovascular death or HF hospitalization or heart transplant or durable left ventricular assist device
Secondary endpoint measured from cardiovascular death, heart transplant or durable left ventricular assist device
Time frame: 5.5 years
Change in NYHA Classification at 12 months
Secondary endpoint measured from New York Heart Association class
Time frame: 12 months
Change in Six Minute Walk Test performance at 12 months
Secondary endpoint measured from Six Minute Walk Test
Time frame: 12 months
Patient activity measured through cardiovascular implantable electronic devices (CIED) at 12 months
Measurement Patient activity measured through cardiovascular implantable electronic devices (CIED)
Time frame: 12 months
Change in NT-proBNP at 12 months
Measurement of heart failure serum biomarker NT-proBNP
Time frame: 12 months
Appropriate ICD therapy for ventricular arrhythmias
Antitachycardia pacing or ICD shocks
Time frame: 5.5 years
Incidence of atrial tachyarrhythmia events
Atrial arrhythmia event measured through cIED
Time frame: 5.5 years
Change in Left Ventricular Ejection Fraction (LVEF) at 12 months
Measurement of LVEF before and at 12 months after implant using echocardiography
Time frame: 12 months
Plan to share: No
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