Catheter ablation in congenital heart diseases: a French nationwide study

Current evidence on catheter ablation for patients with congenital heart disease (CHD) is derived from small, retrospective studies. This study aims to provide insights from a nationwide contemporary registry.

This prospective study included all CHD patients referred for catheter ablation from 2020 to July 2024 across 28 French centres. The primary outcome was the rate of per-procedural acute success. Secondary outcomes included complications as well as freedom from arrhythmia recurrence.

A total of 1135 consecutive catheter ablation procedures were performed in 998 patients (mean age 46.1 ± 16 years, 55.5% male). The main primary clinical arrhythmias targeted were atrial flutter/tachycardia in 677 (59.6%), atrial fibrillation in 195 (17.2%), ventricular arrhythmia in 188 (16.6%), and atrioventricular reentrant tachycardia in 38 (3.3%), with significant variations in patterns observed based on the underlying substrate. Clinical arrhythmia was successfully ablated in 1071 patients (94.4%). The mean number of arrhythmias targeted per procedure was 1.5 ± 0.7, with overall acute success rates exceeding 90% for all arrhythmias except for ventricular arrhythmias (86.7%). Acute complication occurred in 43 procedures (3.8%), including 1 (0.1%) death. The overall 1- and 2-year recurrence-free rates were 77.3% (95% confidence interval 74.2%-80.4%) and 68.4% (95% confidence interval 64.7%-72.3%), respectively. Significant variations in recurrence rates were noted based on the type of arrhythmia and the underlying CHD.

Catheter ablation in patients with CHD demonstrates highly favourable acute outcomes and a low complication rate. Recurrence rates during follow-up vary depending on the targeted arrhythmia and the underlying CHD. These findings should be considered in the benefit-risk assessment.