胸部大動脈人工血管置換術後に送血用人工血管側枝に形成された仮性動脈瘤

Pseudoaneurysm Arose from the Side Branch of Vascular Graft after Thoracic Aortic Replacement

胸部大動脈人工血管置換術後の遠隔期における仮性動脈瘤の発生頻度は0.5％程度と報告されている1）．仮性動脈瘤の多くは吻合部仮性動脈瘤であり，非吻合部の仮性動脈瘤はきわめてめずらしい．われわれは，胸部大動脈人工血管置換術後に送血用人工血管側枝に起因する仮性動脈瘤を経験したので報告する．

The patient is a 52-year-old man. He underwent ascending aortic replacement for acute aortic dissection 21 years ago and aortic root replacement 15 years ago. During postoperative follow up, a pseudoaneurysm of the ascending aorta was found. Cause of the pseudoaneurysm was supposed to be injury of the anastomotic site by a sternal wire. Since the pseudoaneurysm was enlarging, operation was indicated. Incising the pseudoaneurysm, we did not find silk threads that were used for ligation of the side branch of the vascular graft, and there was bleeding from the side branch. It is reported that silk threads lose strength in vivo over time. Previously, we had ligated side branches of vascular grafts only with silk threads. This experience led us to add polypropylene sutures for ligation of side branches.