Immediate and long-term efficacy and safety of catheter ablation of right anteroseptal atrio-ventricular accessory pathways

This study investigated long-term outcome of catheter ablation of right anteroseptal atrio-ventricular (AV) accessory pathways (AP) located close to the His bundle. Methods: Between April 2003 and June 2011, 26 patients (6 females, age 35 13 years) underwent catheter ablation of right anteroseptal AP. These APs represented 10% of all 248 APs ablated within the given reference period. Elimination of AP conduction in both directions and preservation of normal AV conduction were the ablation procedure endpoints. Results: First ablation was effective in 18 (69%) patients. After repeat ablation, AP was permanently eliminated in 22 (85%) patients (one, two, and three ablation procedures in 16, 5, and 1 patient, respectively). Ablation failed in 4 patients (1 procedure in 3 patients, 2 procedures in 1 patient). During 56 27 (4-102) month follow-up period since the last ablation, no late AP conduction recovery was found, and no late advanced AV block occurred. Post-ablation AV node Wenckebach point was present at the pacing rate of 176 26 (130-230) beats per minute. Of the two engaged operators, more experienced operator successfully accomplished first, second, and third ablation procedure in 14/16 (88%), 5/5 (100%), and 1/1 (100%) patients, respectively, the latter operator attained successful ablation in 4/10 (40%) and 1/2 (50%) patients at the first and second ablation procedures, respectively. Conclusion: Ablation of right anteroseptal AP close to the His bundle is feasible and safe. Late advanced AV block was not observed. Individual operator's experience influenced ablation efficacy.