Background: The maze procedure and its modifications are the surgical treatment for atrial fibrillation. In an attempt to achieve a less invasive operation, we developed a balloon-type device for electric pulmonary vein isolation and evaluated its effectiveness macroscopically and microscopically.
Methods: We created a left heart system model from 20 pigs. Based on a mold, a balloon was made with silicone resin. When this balloon was inflated, all pulmonary vein orifices were pressed and ablated by probes using radiofrequency and cryotherm as energy sources. Macroscopic and microscopic evaluations were performed.
Results: Complete circular ablation by radiofrequency was confirmed in 2 of 3 veins. The transmural denaturation was pathologically confirmed in all areas ablated at 80 degrees for 2 minutes. The complete circular ablation line and the transmural denaturation were macroscopically and microscopically confirmed after cryoablation at -100 degrees for 2 minutes using liquid nitrogen.
Conclusions: This study proved that the balloon is effective in simplifying pulmonary vein isolation and has potential to become an instrument that contributes to less invasive operations in the near future.