Catheter ablation of accessory pathways (APs) in Ebstein anomaly (EA) has been associated with a notoriously high recurrence risk.

To compare outcomes of AP ablation in EA in early (1990-2004) vs. recent (2005-2019) era and identify variables associated with recurrence.

Retrospective review of all catheter ablations for SVT in EA at our institution.

We identified 76 pts with median age 9 yrs (25th-75th: 2.6-13.3). Of these, 52 had AP alone, 12 atrial flutter (AFL), 3 atrioventricular nodal re-entry tachycardia (AVNRT), and 9 had AP plus at least one additional arrhythmia. Of the 61 patients with APs, a total of 78 separate APs were identified: 40 right-sided, 37 septal, and 1 left-sided. Acute success for AP first procedure was 89% and did not differ between early and recent era (89% vs. 88%, p=0.48). However, 19 pts (31%) required repeat procedures (average 1.4/pt) due to AP recurrence or ablation failure at first attempt. In comparison to early era, recent era ablations had significantly lower recurrence rates at 1 year (62% vs. 19%, p=0.005). At a median follow up of 2.5 years (25th-75th: 0.2-7), ultimate AP elimination after all procedures was 93%. Younger age at time of EPS (<2 vs. 12-47 yrs: HR 7.3, p=0.003) and ablation era (early era vs. recent era: HR 3.65, p=0.009) predicted recurrence.

Outcomes for accessory pathway ablation in patients with Ebstein anomaly have improved, but there is still a relatedly high recurrence risk requiring repeat procedures.