Is compliance mismatch the major cause of anastomotic arterial aneurysms? Analysis of 42 cases.

In 1,348 anastomoses carried out prior to 1976 at St. Laurence's Hospital, Dublin, 36 anastomotic aneurysms developed for an incidence of 2.7%. Six further anastomotic aneurysms occurred following repair of anastomotic false aneurysms. Suture material failure, infection or lymphatic leakage were not associated with aneurysm formation. Twenty three aneurysms occurred in eight hundred and sixty Dacron to artery anastomoses while 6 occurred in 420 vein to artery anastomoses. Anastomotic false aneurysms were found only with the Dacron to artery anastomoses. Only 9 of 590 anastomoses performed for abdominal aortic aneurysm developed false aneurysms while 14 occurred in 270 for occlusive atherosclerosis. We have concluded that compliance mismatch producing anastomotic shear stress damages the arterial wall. This structural impairment permits tearing out of sutures from the vessel wall. The process is facilitated by prior loss of structural integrity of the vessel wall.