Objective
The purpose of this study is to compare two pacemaker placement strategies: standard right ventricular pacing (control group) and left bundle branch pacing (LBBP) (experimental group), for patients who have heart block.
Background
Typically, patients who have heart block become dependent on pacemakers (life-saving devices that allow the heart to pump in an organized manner) to deliver electrical signals. If a patient is completely dependent on these electrical signals, they are at risk of developing a weakening of their heart muscle called pacing-induced cardiomyopathy, which is often associated with the development of heart failure. This study is therefore looking at left bundle branch pacing, a novel approach to placing a pacemaker that attempts to prevent the risk of pacing-induced cardiomyopathy and prevent heart failure.
Study Outcomes
Primary
- Cardiovascular death
- Heart failure event: ED visits or hospitalization for HF, intensification of therapy (outpatient IV diuretics), or indication for device upgrade to CRT due to deteriorating LV function (absolute decline in LVEF ≥ 10% from baseline and LVEF ≤ 50%)
- Worsening LV end-systolic volume index (LVESVi) at 2 years, defined as a 15% increase from baseline on the two-year echo
Secondary
Eligibility Criteria
The criteria below are a summary. Your study doctor will confirm whether this study is right for you.
Inclusion Criteria
- Age > 18 years
- Patients with an ejection fraction of > 35%
- Indication for ventricular pacing and high-degree atrioventricular block where anticipated RV pacing is > 90% (e.g. third degree AV block, symptomatic second degree AV block, or first degree AV block > 280 ms with a narrow QRS or > 240 ms with an intraventricular delay)
- An echocardiogram within the last 3 months
Exclusion Criteria
- Indication for an implantable cardioverter defibrillator
- Presence of a mechanical tricuspid valve
- Any prior attempt at implantation of an ICD, CRT, HBP, or LBBP
- Patients in whom the conduction system abnormality is expected to be transient or recover over time
- Permanent atrial fibrillation
- Lack of capacity to consent, or having a substitute decision maker
- Other serious medical condition with life expectancy of < 2 years
- Pregnancy or intention to become pregnant during the trial period
About taking part
If you are considering joining this study, please review the Letter of Information below. It explains the study in detail, including what participation involves, the potential risks and benefits, and your rights as a participant.
LEFT-HF Letter of Information