Comparison of Procedural Outcomes Across Different Septal Accessory Pathway Locations Using Contact Force

The ablation of septal accessory pathways (APs) in pediatric patients presents significant challenges owing to the close proximity of the atrioventricular (AV) node. Our objective was to assess the influence of contact force (CF)-sensing technology combined with a "conservative force" strategy on procedural efficiency and safety within this high-risk demographic.

We retrospectively analyzed 157 pediatric patients who underwent radiofrequency (RF) ablation for septal APs (anteroseptal, midseptal, or posteroseptal). Patients were divided into two groups: the CF group (n = 77), utilizing a target force of 5-12 g, and the non-CF group (n = 80), using conventional irrigated catheters.

The CF group achieved significantly shorter total procedure times (65.0 vs. 80.0 min; p = 0.029) and reduced total RF application times (78.0 vs. 105.0 s; p = 0.047) compared to the non-CF group. In the CF group, the median CF was 10.0 g, and the median RF power was significantly lower than in the non-CF group (25 W vs. 30 W; p = 0.003). Subgroup analysis revealed a significant gain in efficiency for posteroseptal (PS) pathways , whereas anteroseptal (AS) pathways required longer procedure times in the CF era due to safety-driven force titration (105.0 vs. 70.0 min; p = 0.012). Acute success rates (98.7% vs. 93.8%; p = 0.210) and recurrence rates (5.2% vs. 11.3%; p = 0.277) were comparable between the groups. No permanent AV block or major complications occurred in either cohort.

Integrating CF technology with a conservative force strategy (5-12 g) enhances procedural efficiency in pediatric septal AP ablation without compromising safety. While it streamlines the workflow for most septal locations, the AS region requires more meticulous titration, and the midseptal (MS) region remains the most prone to recurrence.