Left Bundle-Branch Pacing Beats Right Ventricular Pacing
The OptimPacing trial found fewer heart failure events and no pacing-induced cardiomyopathy with the left bundle-branch approach.
Updated on Nov. 8, 2026 in Heart Disease
In the OptimPacing trial of nearly 700 people with atrioventricular block, left bundle-branch pacing was associated with a 59% lower risk of death, heart failure hospitalization, or cardiomyopathy than right ventricular pacing. An independent data monitoring committee recommended ending the trial early because of the advantage seen with left bundle-branch pacing.
Why it matters
Atrioventricular block often requires long-term pacing, and the choice of pacing site can influence heart failure and cardiomyopathy risk. The trial results suggest a pacing approach that may reduce these serious complications for patients who depend on a pacemaker.
In the randomized OptimPacing trial, 8.5% of left bundle-branch pacing patients had a primary outcome event versus 19.2% of right ventricular pacing patients over a median 35-month follow-up. Pacing-induced cardiomyopathy developed in 0% of the left bundle-branch group compared with 11.7% of the right ventricular group, and the study does not report outcomes beyond that follow-up period.
The players
OptimPacing trial
A randomized clinical trial comparing left bundle-branch pacing with right ventricular pacing in patients with atrioventricular block.
New England Journal of Medicine (NEJM)
A widely read peer-reviewed medical journal that published the OptimPacing trial results.
The details
Nearly 700 men and women with atrioventricular block, averaging 68 years old and about 58% male, were randomized to left bundle-branch pacing or right ventricular pacing. HF hospitalization occurred in 1.5% of the left bundle-branch group and 2.9% of the right ventricular group, with the lower primary-outcome rate driven mainly by fewer hospitalizations and less pacing-induced cardiomyopathy.
Timeline
Enrollment and tracking of nearly 700 patients took place over a five-year period.
Results were presented at AHA 2026 and published simultaneously in NEJM.
Health Landscape
The OptimPacing trial adds randomized evidence to the ongoing effort to move pacemaker therapy beyond the conventional right ventricular lead. Its finding that left bundle-branch pacing reduced heart failure hospitalizations and pacing-induced cardiomyopathy places it within a growing body of research on physiologic pacing approaches.
For people with atrioventricular block who need a pacemaker, the pacing site may affect the risk of heart failure hospitalization and cardiomyopathy. Patients considering these options should discuss the trial findings and their own cardiac history with their cardiologist.
The takeaway
Choosing where a pacemaker lead is placed may matter as much as whether a pacemaker is used at all. Patients with heart block should ask their care team which pacing approach fits their condition.
Further reading
For more on the conditions behind this research, explore Heart Disease coverage on Wisevoter.
