Radiofrequency ablation of accessory pathways. Contemporary success rates and complications in 323 patients.

Introduction: 17 years ago the first radiofrequency catheter ablation of an accessory pathway (AP) was performed. The aim of this study was to describe the contemporary success rates and procedure related complication rates of radiofrequency (RF) ablation of accessory pathways (APs). In addition, the present study describes the anatomical distribution of APs according to the new nomenclature introduced by NASPE and ESC in 1999.

Methods: The analysis included all patients, who underwent RF ablation of an AP in the Heart Center Leipzig between January 2000 and December 2003.

Results: Over a 4 year period 336 APs were ablated in 323 patients. 201 APs (60%) presented with antegrade and retrograde conduction and showed preexcitation on ECG. For the remaining 135 APs (40%), only retrograde conduction over the AP was documented. According to the new nomenclature APs were classified as left-sided, right sided, septal and paraseptal APs. 188 APs (56%) were located on the left, 41 (12%) on the right, 64 (19%) in the paraseptal space and 31 APs (9%) presented with a septal or parahisian localization, respectively. Because of atypical course and/or characteristics 12 APs (4%) could not be classified. Ablation of all pathways were successful in 315 patients (98%). In 289 patients (89%) success was achieved within a single ablation session. The left-sided pathways had a re-intervention rate of 5%, which was significantly lower compared to the remaining localizations. The highest re-intervention rate was observed in the septal APs (23%). Complications were observed in less than 2% of all treated patients.

Conclusions: 17 years after the first RF catheter ablation of an AP this therapy is established as a highly effective procedure. The success rate has improved to 98% and the complication rate has been minimized to less than 2%. The most frequent localization of APs is left posterior. Left sided APs also presented with the lowest re-intervention rate. The introduction of the new nomenclature in 1999 by NASPE and ESC has simplified the description of the exact anatomical localization of an AP.