[Thoracoscopic bypass from the descending thoracic aorta to the femoral artery. Experimental study and clinical application].

Objective: Descending thoracic aorta to femoral artery bypass (DTAFB) has demonstrated usefulness in the treatment of aorto-iliac occlusive disease but related morbidity and mortality are not negligible. We wanted to determine the feasibility of thoracoscopic DTAFB and to report our clinical experience.

Material And Methods: An experimental study was performed on 8 pigs in helicoidal position under general anesthesia with right selective ventilation ). Three trocars were inserted and the descending aorta was dissected ). After tunnelisation of a 6 mm graft, a lateral aortic anastomosis was thoracoscopically performed ) then femoral anastomoses were made. At the end of the procedure, an angiogram and then an autopsy were performed ). Subsequently, three patients were operated, two for thrombosis of a previous aortobifémoral bypass and one for infrarenal aortic hypoplasia. Dissection and graft tunnelisation were performed thoracoscopically ). Then, the aortic anastomosis ) was constructed through a left lateral minithoracotomy (10 cm).

Results: One pig died during surgery of acute lung oedema due to the difficulties of selective ventilation. Excluding this case, the average times of surgery and of dissection were respectively 246 (205-325) and 68 minutes (50-90). The average aortic clamping and anastomosing times were 135 (105-220) and 120 minutes (80-210) ). Three aortic tears were noted; one was repaired. Angiogram was normal 5 times; one pig had a minor stenosis and a leak, and another one had a leak. All the anastomoses were patent without stenosis at autopsy; no organ lesion was found. In humans, the procedure was performed with simple postoperative course in 2 patients and a conversion (20 cm long thoracotomy) was necessary for the third due to poorly supported selective ventilation.

Conclusion: Totally thoracoscopic DTAFB can be performed in pigs. In clinical practice, we recommend the use of a mini thoracotomy. This way, the aortic anastomosis can be performed with aortic clamping time under 30 minutes, reducing the risk of spinal cord ischemia. These results allow to propose mini invasive thoracoscopically assisted DTAFB for the patients for whom laparoscopic access of the abdominal aorta appears to be difficult (calcified aorta, hostile belly.).