Submucosa of canine small intestine as an alternative medium-diameter autogenous arterial graft

Background. Small intestinal canine submucosa has been used in previous stu dies as a large diameter arterial graft and has shown acceptable patency ra tes. The aim of our experimental study was to assess its effectiveness when it is used as an autogenous medium-sized diameter arterial graft (5-7 mm). Methods. Fifteen mongrel dogs were included and underwent laparotomy under general anaesthesia. The mucosa, tunica muscularis and serosa were removed from a resected intestinal segment. The remaining tube, which consisted of the submucosa and the basilar tunica mucosa, represented the experimental g raft which was used to replace a proportional gap of the canine infrarenal aorta. Ascertainment of peripheral pulses, measurement of the intra-aortic pressures, aortography and in vivo/in situ observation before the sacrifice of the animals, were the procedures used for verification of the graft's p atency. Results. The resistance to thrombogenicity of the graft was considered sati sfactory: nine out of 10 grafts remained patent for postoperative intervals ranging from one day to one year; one graft showed partial obstruction due to a technical perioperative error. The grafts showed also excellent physi cal characteristics (ease of handling and suturing, blood impermeability an d durability), resistance to infection and showed no tendency to develop my ointimal hyperplasia. Conclusions. Small intestinal canine submucosa showed satisfactory haemodyn amic properties, long-term patency and resistance to infection,when used as a medium-diameter arterial substitute.