VIDEO-ASSISTED THORACOSCOPIC AND CARDIOSCOPIC RADIOFREQUENCY MAZE ABLATION

The authors examined the feasibility of transthoracic radio frequency Maze ablation of atrial fibrillation using video assisted thoracoscopy and cardioscopy in the experimental setting of a beating porcine hear t. In six pigs under general anesthesia, the left atrium was viewed us ing a video assisted thoracoscopy system (VATS), and radiofrequency li near ablation of the left atrial wall was carried out using a radiofre quency ablation catheter (HAT200S:OSYPKA) inserted through a trocar po rt. The right atrium was also ablated in the same manner under VATS. I n six other pigs, intravenous radiofrequency ablation by cardioscopic catheter device was carried out. Atrial fibrillation was provoked by a cetylcholine injection plus rapid atrial pacing. The thoracoscopic vis ual field created for radiofrequency catheter ablation from a transtho racic approach and the cardioscopic visual field from an intravenous a pproach were sufficient, and safe positioning of the ablation catheter device on the atrial epicardium and endocardium, which enabled linear ablation of the atrium, was obtained. The Optimal setting for ablatio n was 70-80 degrees C/30 sec duration per each ablation. This process was monitored and documented by a video system through the thoracoscop e and cardioscope, and results were confirmed by postmortem macrohisto logic examination. In conclusion, the authors' results suggest the pot ential usefulness of the combination of transthoracic radiofrequency c atheter ablation with video assisted thoracoscopic and cardioscopic li near ablation of atrial fibrillation, and the possibility that use of this system might eliminate the need for open heart Maze surgery.