The comparative development of atherosclerosis in the normal aorta, synthetic vascular grafts and endarterectomized aorta

Abstract

Summary A segment of abdominal aorta in mongrel dogs was endarterectomized, removing the intima and 50 to 75 per cent of the media. A dacron bypass graft was then sutured end to side to the endarterectomized segment, and end to side to the normal aorta proximally or distally, doubly ligating the bypassed aorta at both ends. The thyroid gland was removed surgically and the dogs placed on a 5 per cent cholesterol diet and given 50,000 units vitamin D daily. They were sacrificed two to seven months later, at which time the proximal abdominal aorta had significantly more atherosclerosis than the dacron graft or endarterectomized aorta. The new intima lining the dacron graft was almost identical with that lining the endarterectomized segment of aorta, and both areas of new intima were quite resistant to the development of atherosclerosis. The caliber of the endarterectomized aorta was the same as that of the proximal aorta, without any evidence of increased fibrosis about it. There was no evidence that arterial suture lines were more susceptible to atherosclerosis than the adjacent vessels.