# The impact of right ventricular lead position on outcomes in cardiac resynchronization therapy patients

## TL;DR

This study examines how the position of a heart device lead affects outcomes in patients receiving cardiac resynchronization therapy.

## Contribution

The study identifies optimal right ventricular lead positions to improve therapy response and reduce arrhythmia risk.

## Key findings

- Middle septal and left bundle branch area pacing improved electrical synchronization and reduced non-response rates.
- Low septal positioning was linked to higher non-response and arrhythmia risks.
- QRS wave shortening and ventricular remodeling were better in middle septal and left bundle branch groups.

## Abstract

The effect of right ventricular (RV) lead position on the response to cardiac resynchronization therapy (CRT) remains unclear. We evaluated the effects of different RV lead positions on electrophysiology, echocardiography, and clinical outcomes.

This was a retrospective cohort study. A total of 253 patients received CRT with left ventricular (LV) leads implanted in the LV posterolateral coronary vein were included in this study. According to the position of RV lead, the patients were divided into low septal (LSP) group (141 cases), medium septal (MSP) group (36 cases), high septal (HSP) group (32 cases) and left bundle branch area pacing (LBBAP) group (44 cases). The primary endpoint included a composite of rehospitalization for heart failure (HF) and all-cause mortality, assessed using Kaplan–Meier and Cox proportional hazards analyses. Secondary endpoints included changes in CRT response, arrhythmic events, device-related complications, pacing parameters, QRS duration, and echocardiographic parameters at 12-month follow-up.

There were no statistically significant differences in baseline characteristics among the four groups. The non-response rate of CRT (defined as failure to achieve an increase in LVEF >10% and an improvement in NYHA class by at least 1 grade) in the LSP group (48.2%) was higher than that in the HSP group (34.4%), MSP group (16.7%) and LBBAP group (18.2%) (P < 0.008), and the risk of ventricular arrhythmia was the highest (P = 0.003). QRS wave shortening and LV reverse remodeling were significantly greater in MSP and LBBAP groups than in LSP and HSP groups (P < 0.05). During a mean follow-up of (22.7 ± 4.4) months, the composite endpoint of heart failure rehospitalization and all-cause death did not differ significantly among the four groups (P > 0.05).

RV middle septum or left bundle branch area pacing may improve electrical synchronization, reverse ventricular remodeling, and reduce the incidence of non-response to CRT and arrhythmia in patients with heart failure receiving CRT.