RADIOFREQUENCY ABLATION OF CONCEALED LEFT FREE-WALL ACCESSORY PATHWAYS WITHOUT CORONARY SINUS CATHETERIZATION - RESULTS IN 100 CONSECUTIVE PATIENTS

Ablation of Concealed Accessory Pathways. introduction: Feasibility of radiofrequency (RF) ablation using a two-catheter technique without c oronary sinus catheterization was studied in 100 consecutive patients with a single concealed left free-wall accessory pathway. Methods and Results: Tachycardia was induced by electrical stimulation in the righ t atrium/right ventricle, and the presence of a concealed left free-wa ll accessory pathway was suggested electrocardiographically (negative P wave in leads I and/or aVL during orthodromic tachycardia) or by ear lier atrial activation in the pulmonary artery compared to the high ri ght atrium, Mapping of the mitral annulus was performed during right v entricular pacing or orthodromic tachycardia, and RF energy was applie d at the site with the earliest retrograde atrial activation. Ablation was considered effective if tachycardia could not be induced, and if VA dissociation or exclusive retrograde nodal conduction was observed, Ablation was initially successful in 98 of 100 patients, Mean number of radiofrequency pulses were 3.2 +/- 2. Mean fluoroscopy time and tot al procedure time was 14 +/- 9 and 107 +/- 32 minutes, respectively. T here were no complications related to the procedure. At a mean follow- up of 22 +/- 13 months, two patients experienced tachycardia recurrenc e and required a second procedure, which was successful. Conclusions: Our results suggest that RF catheter ablation of concealed left free-w all accessory pathways can be safely, effectively, and rapidly perform ed using a simplified two-catheter technique with no need for coronary sinus catheterization.