Aortocaval fistulae: a percutaneous model and treatment with stent grafts in sheep.

Abstract

Treatment of aortocaval fistulae (ACFs) by open surgery is known to be a high-risk procedure. In this experimental study, we developed a percutaneous model of ACF to test a new nonsurgical method of treatment of ACF using endovascular stent grafts. An ACF was created percutaneously in eight sheep. Via a combined venous and arterial femoral approach, angioplasty balloons were inserted to occlude the infrarenal aorta and inferior vena cava (IVC). The IVC was punctured through the lateral aortic wall with a transjugular liver biopsy needle. The fistulous tract was then dilated with an 8-mm angioplasty balloon, and the animal was heparinized. Two weeks later, a 10-mm Cragg-Endopro-Stent was inserted into the aorta at the level of the fistula via a percutaneous femoral approach. ACFs were successfully created in all animals, with rapid dye shunt through the fistula and a 20% increase in cardiac pulsations. Follow-up angiograms at 2 weeks showed a patent ACF, and stent implantation excluded the fistula in every case. Angiographic and pathological examinations up to 6 months demonstrated normal aortic patency and persistent exclusion of the fistulae. ACFs were effectively treated by endovascular grafting of the aorta. The animal model and the stenting procedures were both performed percutaneously.