A standardized low-fluoro approach to perform atrio-ventricular nodal re-entrant tachycardia ablation. PICENO AVNRT

Background Atrioventricular nodal re-entrant tachycardia (AVNRT) ablation is highly effective but carries an unpredictable 1–2% risk of complete AV block, even when energy is delivered to the posterior aspect of Koch’s triangle. The use of Koch’s triangle pace mapping (KTPM) can identify atypical AV nodal locations, while voltage bridge mapping (VBM) helps target the slow pathway. However, a fully standardized, reproducible, and fluoroless approach integrating both techniques has not been established. Purpose To assess the feasibility, efficacy, and safety of a fully standardized, zero-fluoroscopy AVNRT ablation workflow combining 3D KTPM and VBM (PICENO protocol). Methods We retrospectively analyzed 150 consecutive patients (mean age 61 ± 23 years; 47% female) undergoing AVNRT ablation at a single center using the PICENO protocol with CARTO 3D electroanatomical mapping. The stepwise approach included 3D KTPM to localize the anterograde AV node and VBM to define the slow pathway region. In cases with mid-septal or posterior AV nodal extension, VBM-guided cryoablation was employed. All procedures were performed in a single-day hospital setting. Results Procedural success was achieved in all patients with zero fluoroscopy exposure (mean procedure time 62 ± 14 min). The 3D KTPM and VBM steps were successfully completed in all cases. In 4 patients (2.7%) with mid-septal AV nodal extension, cryoablation was performed safely. After a mean follow-up of 30 ± 19 months, no AV block, or major complications occurred. Only 2 recurrences were observed but both of them in the group with RF ablation. The protocol also provided sufficient procedural confidence to safely employ irrigated catheters in selected cases. Conclusion The PICENO protocol enables a standardized, fully fluoroless workflow for AVNRT ablation, ensuring safety, reproducibility, and complete elimination of radiation exposure. The integration of 3D KTPM and VBM enhances anatomical precision and procedural confidence, potentially redefining the standard of care for slow pathway ablation.