Dacron graft Kinking following ascending aorta replacement is not only a cosmetic issue

A 58-year-old man who undergone ascending aorta replacement started to complain of pain in the lower limbs, shortness of breath and progressive fatigue a few months after surgery. Transthoracic and transesophageal Doppler echocardiography revealed a diseased bicuspid aortic valve and a subocclusive mass in the ascending aorta. A thoracic angio-CT confirmed the presence of a subocclusive mass, pseudoaneurysm formation and a distorted shape of the Dacron graft. The patient underwent urgent surgery to remove the mass, which appeared to be a thrombus, aortic valve and ascending aorta replacement in toto. Kinking of vascular graft has been reported including surgical techniques to correct the excessive length to avoid gradients and guarantee laminar flow. When kinking is severe, high gradients and hemolysis can be detected. However, thrombus formation in the ascending aorta segment is less likely because of the high blood velocity flow. Therefore, several concurrent causes should be considered. In the present case, the most probable explanation for the thrombus formation was kinking of a too long Dacron graft, combined with extrinsic compression effect of the graft by the pseudoaneurysm at the anastomosis site and anomalous flow directed from the diseased bicuspid aortic valve. Various grades of Dacron graft kinking might occur following ascending aorta replacement and undiagnosed at follow-up especially if resulting in mild symptoms, thus, careful visual and echocardiography evaluation should be done at the end of surgery. Finally, distorted Dacron graft might trigger thrombus formation when inflammation and coagulation processes are set off during bacteria or viral infection.