Efficacy and safety of a sandwich ablation strategy for idiopathic PVCs: insights from a propensity-matched cohort

Background Catheter ablation of idiopathic premature ventricular contractions (PVCs) is often limited by intramural or anatomically complex substrates. Targeting only the site of earliest activation may result in incomplete lesion formation and arrhythmia recurrence. This study evaluated the efficacy and safety of a systematic, anatomy-guided dual-sided ("sandwich") ablation strategy compared with conventional single-sided ablation. Purpose To determine whether a planned anatomy-guided sandwich ablation approach improves recurrence-free survival compared to conventional ablation and to identify patient subgroups deriving the greatest benefit. Methods In this single-center retrospective study, 509 consecutive patients undergoing ablation for idiopathic PVCs between January 2020 and December 2024 were screened. After exclusions and 1:1 propensity score matching for left ventricular ejection fraction (LVEF), QRS duration, PVC burden, and localization, 194 patients (97 pairs) were included. In the sandwich group, after acute elimination of PVCs at the earliest activation site, additional lesions were systematically delivered from anatomically adjacent or contralateral surfaces (e.g., aortic cusps, RVOT, or coronary venous system). The primary endpoint was recurrence-free survival (no sustained ventricular arrhythmia or >1% PVC burden). Major procedural complications were assessed as the safety endpoint. Results The mean age of the matched cohort was 50.6 ± 11.3 years, and 52% were male. Sandwich ablation was associated with significantly higher recurrence-free survival compared with conventional ablation (94.8% vs. 78.4%, p = 0.001). The benefit was particularly evident among patients with borderline activation timing (EAT > –30 ms: 92.5% vs. 60.5%, p < 0.001). On multivariate Cox regression, sandwich ablation independently predicted lower recurrence (adjusted HR 0.28, 95% CI 0.10–0.76, p = 0.013), while EAT ≤ –30 ms, LVEF <50%, and longer ablation duration were associated with higher recurrence. The overall complication rate was low and comparable between groups (3.1% each). Conclusions A planned, anatomy-guided sandwich ablation strategy significantly improves long-term arrhythmia-free survival without increasing procedural risk. The greatest benefit occurs in patients with early but not markedly premature activation (EAT > –30 ms), suggesting that these cases may involve intramural or epicardially insulated substrates inadequately treated by conventional single-sided ablation. Integrating activation-based risk stratification into procedural planning may enhance lesion transmurality and optimize outcomes in idiopathic PVC ablation.