Abstract
Background: Premature ventricular contractions (PVCs) originating from non–outflow tract regions are uncommon in clinical practice but pose significant challenges for catheter ablation due to complex anatomical and electrophysiological characteristics. Objectives: To evaluate the clinical features and acute procedural outcomes of radiofrequency catheter ablation in patients with non–outflow tract PVCs. Methods: This cross-sectional study included 27 patients with non–outflow tract PVCs who underwent radiofrequency catheter ablation at the Vietnam National Heart Institute – Bach Mai Hospital and Hanoi Medical University Hospital between September 2024 and October 2025. Baseline clinical data, echocardiographic parameters, and procedural characteristics were collected and analyzed according to the PVC origin site. Results: Non–outflow tract PVCs accounted for 12.4% of all ablated PVC cases. The most common origins were the tricuspid annulus (33.3%), followed by mitral annulus (25.9%), papillary muscles (22.2%), and parahisian region (18.5%). The overall acute success rate was 81.5%, with the highest success observed in PVCs from the mitral annulus (100%) and lower rates in papillary muscle (66.7%) and parahisian (60%) PVCs. Patients with papillary muscle PVCs had lower mean left ventricular ejection fraction, longer procedure duration, and longer ablation time compared with other groups. No major complications occurred. Conclusions: Radiofrequency catheter ablation is an effective and safe therapeutic option for non–outflow tract PVCs. However, procedural difficulty and success rates vary by anatomical site. Larger studies with long-term follow-up are needed to further validate these results.
