Conduction System Pacing With Left Bundle Branch Pacing as Compared to Standard Right Ventricular Pacing

McGill University Health Centre/Research Institute of the McGill University Health Centre1,300 enrolled

Overview

High burden right ventricular (RV) pacing has been shown to increase cardiovascular mortality, incidence of heart failure (HF), worsen left ventricular (LV) function and accelerate the development of atrial fibrillation (AF). High percentage ventricular pacing and wider paced QRS in the setting of normal baseline LV ejection fractions have consistently been shown to be independent risk factors for pacing-induced cardiomyopathy. Left bundle branch pacing (LBBP) has emerged as a potential alternative pacing mechanism that may avoid LV dyssynchrony and pacing-induced LV dysfunction by mimicking native electrical conduction.

We hypothesize that in patients with high degree AV block with anticipated ventricular pacing \>90%, and an EF \>35% patients undergoing LBBP will demonstrate a significantly lower number of the primary composite endpoint of cardiovascular death, heart failure events, and change in LVESVi as compared to standard RV pacing. Echos will be performed at baseline, 12, 24, and 36 months. NTproBNPs are performed at baseline and follow-up. There will be a core echo lab, and blinded adjudication of ECGs and events.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Enrollment

1,300

Conditions

Pacemaker DDD Heart Block

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: 1. Age ≥ 18 years 2. Patients with an ejection fraction of \>35% 3. Patients with an indication for ventricular pacing and high-degree atrioventricular block where the degree of anticipated RV pacing is \>90% including: 1. Third degree AV block 2. Symptomatic or asymptomatic second-degree AV block 3. First degree AV block ≥ 280ms with a narrow QRS, or ≥ 240ms with an intraventricular delay (QRS duration ≥120ms) 4. Echocardiogram within the last 3 months, with ability to have DICOM images Exclusion Criteria: 1. Indication for an implantable cardioverter defibrillator 2. Presence of a mechanical tricuspid valve 3. Any prior attempt at implantation of an ICD, CRT, HBP, or LBBP 4. Lack of capacity to consent 5. Other serious medical condition with life expectancy of \<2 years 6. Pregnancy 7. Patients in whom the conduction system abnormality is expected to be transient or recover over time 8. Patients with permanent atrial fibrillation

Outcomes

Primary Outcomes

Time to cardiovascular death

Clinical

Time frame: 36 months

Time to first heart failure event

Defined as: (i) Emergency department (ED) visits or hospitalization for HF (requiring signs and symptoms consistent with congestive heart failure (CHF) that is responsive to oral or parenteral medications); (ii) intensification of therapy (intravenous diuretic therapy on an outpatient basis); or (iii) indication for device upgrade to CRT due to deteriorating LV function defined as an absolute decline in LVEF ≥ 10% from baseline and an LVEF ≤ 40%

Time frame: 36 months

Worsening LV end systolic vloume index at 2 years

Defined as a 15% increase from baseline on the two-year echo

Time frame: 24 months

Secondary Outcomes

Cardiovascular mortality

CV-related

Time frame: 24 months

New visit for Heart Failure

Heart failure visit is defined as: i) Emergency department visit or hospitalization for signs and symptoms of HF that is responsive to oral or intravenous diuretics ii) intensification of therapy defined as outpatient intravenous diuretic therapy, and iii) device upgrade to cardiac resynchronization therapy.

Time frame: 24 months

Total mortality

Time frame: 24 months

Change in left ventricular ejection fraction

Echo parameter, change from baseline to 24 months

Time frame: 24 months

Change in NTproBNP level

From baseline to 24 months

Time frame: 24 months

Atrial fibrillation progression

Atrial fibrillation burden as noted on pacemaker

Time frame: 24 months

Development of new tricuspid regurgitation

More than mild TR from baseline

Time frame: 24 months

Presence of Mitral regurgitation

Progression/Development from baseline

Time frame: 24 months

Change in Lead parameter

stability of impedance, sensing, thresholds

Time frame: 24 months

Quality of Life Improvement

Health related quality of life score: Short Form 12

Time frame: Evaluated at 1, 12, and 24 months, measure as compared to baseline

Safety of procedure and long-term safety

Procedural and long-term safety of left bundle pacing

Time frame: 24 months

Conduction System Pacing With Left Bundle Branch Pacing as Compared to Standard Right Ventricular Pacing

Overview

Conditions

Interventions

Eligibility

Locations (1)

Outcomes

Primary Outcomes

Secondary Outcomes

Central Contacts