Penetrating Atherosclerotic Ulcerが原因と考えられた腹部大動脈瘤の1例

A Case of Abdominal Aortic Aneurysm associated with a Penetrating Atherosclerotic Ulcer

要旨

　penetrating atherosclerotic ulcer(PAU)が原因と考えられた腹部大動脈瘤の1例を経験した．患者は54歳，男性．腰痛を主訴に来院した．腹部造影CTにて，内腔が一方向へ突出，瘤化し，それに隣接する壁在血栓を認めた．腹部大動脈瘤破裂の診断にて緊急的に手術を施行した．腹部大動脈表面には血腫を認め，内膜は高度の動脈硬化性変化とpunched out 様の内膜欠損が認められた．人工血管置換術を行い，経過良好であった．病理組織学的には，血管壁の著明な動脈硬化性変化に加え，瘤壁での内膜，内弾性板の消失，中膜の断裂，外膜にいたる血腫がみられ，Stansonらの提唱するPAUの所見と一致した．

Summary

　We encountered a case of abdominal aortic aneurysm associated with a penetrating atherosclerotic ulcer. A 54-year-old man with the complaint of lumbago was admitted to our hospital. Enhanced CT images demonstrated an infrarenal abdominal aortic aneurysm with a contrast material-filled ulcer surrounded by hematoma. An emergency operation was performed with a diagnosis of ruptured aortic aneurysm. During the operation, multiple atherosclerotic changes were observed, and a clot-filled “false lumen” was identified through “punched-out” like intimal defect. The abdominal aorta was replaced with a bifurcated prosthetic graft. The postoperative course was uneventful. Histopathological findings showed that the aorta had undergone extensive atherosclerotic changes, the intima was abscent, and hematoma extended into the adventitia in the aneurysmal wall. Those findings were compatible with “penetrating atherosclerotic ulcer” was described by Stanson et al.