# Safety of leadless versus transvenous pacemakers in patients with low body surface area: a matched-pair analysis

## TL;DR

The study compares the safety of leadless pacemakers in patients with low body surface area and finds no increased risk of complications compared to transvenous pacemakers.

## Contribution

This study provides new evidence on the safety of leadless pacemakers in patients with low body surface area, particularly in Asian populations.

## Key findings

- Low-BSA LP patients had similar complication rates as normal-BSA LP patients.
- No significant difference in complications was found between low-BSA LP and matched transvenous pacemaker patients.
- Findings suggest LPs may be safe in low-BSA patients despite concerns about venous access.

## Abstract

Leadless pacemakers (LPs) avoid lead- and pocket-related issues but require large venous access, which raises safety concerns in patients with a small body surface area (BSA), particularly in Asian populations. We defined low BSA as < 1.46 m², based on validated 3D-derived anthropometric standards for Chinese adults.

To assess procedural complication rates of LP implantation in patients with low BSA.

We analyzed LP implantations from 2016 to 2025 at a single center in Thailand. Of 59 patients, 25 (42.4%) had low BSA. We conducted two comparisons: (1) low- vs. normal/high-BSA LP patients and (2) low-BSA LP patients with a 1:2 age-, sex-, and BSA-matched transvenous pacemaker (TVP) cohort. The primary outcome was major device-related complications.

LP patients were elderly (median 79 years) with high comorbidity (median Charlson Comorbidity Index [CCI], 7.0). In the matched analysis, low-BSA LP patients had a significantly higher comorbidity burden than TVP controls (median CCI, 7.0 vs. 5.0; P = 0.002). The 3.8-year cumulative incidence of major complications did not differ between low- vs. normal/high-BSA LP patients (8.0% vs. 8.8%, P = 0.39) and between low-BSA LP patients vs. matched TVP controls (8.0% vs. 14.0%, P = 0.91). Adjusted analyses revealed no significant association between device type and complications, although the confidence intervals were wide.

In this exploratory analysis, patients with low-BSA showed no increased risk of major complications following LP implantation. However, given the small sample size and pronounced selection bias, these findings should be interpreted with caution.

The online version contains supplementary material available at 10.1186/s12872-026-05526-0.