Transformation of nonvascular acellular tissue matrices into durable vascular conduits

Background. Prosthetic grafts commonly used for vascular reconstruction are limited to synthetics and cross-linked tissue grafts. Within these devices , graft infections are common, compliance mismatch is significant, and hand ling qualities are poor. Natural biological tissues that are unfixed have b een shown to resist infections and be durable and compliant. A natural biol ogical matrix that could be remodeled appropriately after implantation woul d be a desirable graft for vascular reconstruction. Methods. SynerGraft tissue engineering strategies have been used to minimiz e antigenicity and produce stable unfixed vascular grafts from nonvascular bovine tissues. These grafts have replaced the abdominal aortas of 8 dogs t hat have been followed for up to 10 months. Results. Early evaluation indicates rapid recellularization by recipient sm ooth muscle actin positive cells, which become arranged circumferentially, into the media. Arterioles were present in the adventitial areas and endoth elial cells were seen to cover lumenal surfaces. After 10 months, grafts we re patent and not aneurysmal. Conclusions. These data indicate that SynerGraft processing of animal tissu es is capable of producing stable vascular conduits that exhibit long-term functionality in other species. (C) 2001 by The Society of Thoracic Surgeon s.