Intraoperative radiofrequency ablation of chronic atrial fibrillation: A left atrial curative approach by elimination of anatomic "anchor" reentrant circuits

Intraoperative Ablation of Atrial Fibrillation. Introduction: The percutane ous approach to radiofrequency (RF) catheter ablation for curative treatmen t of atrial fibrillation (AF) is an investigational technique, and the opti mal composition of lesion lines is unknown. We tested an intraoperative RF ablation concept with elimination of left atrial anatomic ''anchor" reentra nt circuits. Methods and Results: In 12 patients with an indication for valve surgery an d chronic AF, a right atrial-transseptal approach was chosen for access to the left atrium, AF had been present for 4.3 +/- 3.9 years; the left atria measured 56 +/- 7 mm, Under direct vision, contiguous lesion lines were pla ced endocardially with temperature-guided RF energy applications for treatm ent of AF with a specially designed probe. The lesion lines were placed bet ween the mitral annulus and the left lower pulmonary, vein, further to the left upper pulmonary vein, from there to the right upper pulmonary vein, an d finally to the right lower pulmonary rein. The antiarrhythmic ablation pr ocedure lasted 19 +/- 4 minutes. One patient died postoperatively of low ca rdiac output. During follow-up of 11 +/- 6 months, chronic AF was ablated s uccessfully in 9 of 11 patients (82%). Sh patients mere in stable sinus rhy thm or intermittent pacemaker rhythm, and three patients were in sinus rhyt hm with intermittent atypical atrial flutter, Conclusions: Intraoperative RF energy application for induction of contiguo us lesion lines is feasible, Elimination of anatomically defined "anchor"' reentrant circuits within the left atrium prevented chronic AF in > 80% of the patients treated. Intraoperative validation of lesion line concepts for curative treatment of AF mag be transferred to percutaneous ablation techn iques.