Approaching a paradigm shift: endoscopic ablation of lone atrial fibrillation on the beating heart

Percutaneous catheter ablation has been the preferred treatment strategy for many patients with symptomatic drug-refractory atrial fibrillation (AF). However, incomplete ablation lines and varying success rates remain a problem in certain subgroups. This article evaluates the feasibility and efficacy of endoscopically performed left atrial ablation in patients with lone AF.

Epicardial bipolar radiofrequency ablation was performed on the beating heart through a bilateral endoscopic approach in 89 consecutive patients with lone AF. This included isolation of the pulmonary veins using a clamp; isolation of the posterior left atrial wall, including a trigonal line to the aortic noncoronary sinus using a linear ablation device; and resection of the left atrial appendage (LAA). Preoperative, perioperative, and postoperative data were collected prospectively and included questionnaires and 24-hour Holter monitoring at 6 and 12 months and annually thereafter.

Mean follow-up was 12±6 months (range, 4-28 months). No patients were lost to follow-up. Mean duration of AF was 6.4±5.7 years, with 35% paroxysmal AF and 65% persistent or long-standing persistent AF. Mean operation time was 180±43 minutes. There were no deaths, no conversion to sternotomy, and no early or late stroke. Freedom from AF was 88%, 90%, and 90% at 6, 12, and 24 months, respectively. Freedom from AF without antiarrhythmic drugs was 71%, 82%, and 90% at 6, 12, and 24 months, respectively.

Endoscopic radiofrequency ablation on the beating heart reveals high success rates with low procedure-related morbidity. For improvement of future treatment strategies, a randomized trial is advisable to compare this procedure with catheter ablation in certain patient subgroups.