Catheter ablation of ventricular arrhythmias originating from para‐Hisian region with reversed C‐curve technique

AIMS: Ventricular arrhythmias (VAs) originating from the para-Hisian region represent a challenging location. The long-term success rate of catheter ablation above the septal leaflet of the tricuspid valve is not ideal. This study aimed to investigate the safety and efficacy of catheter ablation for para-Hisian VAs via a direct approach under the septal valve with reversed C-curve technique. METHODS AND RESULTS: Twenty-five consecutive patients with para-Hisian VAs were included. Systematic mapping was performed in the right ventricle septum, including both the regions above and under the septal valve. Radiofrequency (RF) ablation was preferentially performed under the valve with reversed C-curve technique in all patients. If the ablation failed under the valve, it was then performed above the valve and even in aortic sinus cusps. The earliest ventricular activation preceding surface QRS (V-QRS) under the valve was significantly larger than that above the valve (34.8 ± 5.3 vs 27.8 ± 5.7 ms, P < .01). RF ablation under the valve with reversed C-curve technique achieved acute success in 22 of 25 (88%) patients. Junctional rhythm developed during ablation in 3 of 25 (12%) patients and no atrioventricular block occurred. In the remaining three patients, RF application above the valve failed to eliminate the VAs and one of them achieved successful ablation in the right coronary cusp. During a mean follow-up of 17.8 ± 9.4 months, no patients presented with VAs recurrence and no postprocedure complications occurred. CONCLUSIONS: Catheter ablation under the valve with reversed C-curve technique shows to be effective and safe for para-Hisian VAs.