大動脈弁置換術後の巨大上行大動脈瘤に対する上方胸骨部分切開

Upper J Partial Sternotomy during Re-do Surgery for a Giant Ascending Aortic Aneurysm

胸骨に接する上行大動脈瘤に対する手術，特に再手術では胸骨正中切開時に大動脈損傷をきたす可能性が高い．大動脈損傷をきたした場合は時に致命的である．対策として，人工心肺を大腿動脈や腋窩動脈送血，大腿静脈からの脱血管挿入などで開始し，場合によっては超低体温として循環停止下に胸骨正中切開を行うことなどが報告されてきた1，2）．われわれは大動脈弁置換術後の巨大上行大動脈瘤症例に対して，人工心肺下であるが，まず上方胸骨部分切開を行い，上行大動脈遠位側をテーピングし，上行大動脈遮断をできる状態とした後に全胸骨正中切開を施行し，安全に上行大動脈置換術を施行することができたので報告する．

A 79-year-old woman with a history of aortic valve replacement using a mechanical valve was referred to our hospital due to a giant ascending aortic aneurysm just beneath the sternum. As the initial step of the surgery, the upper sternum was partially divided in J shape under cardiopulmonary bypass with cannulae in the femoral artery and vein. After securing the distal portion of the ascending aorta, full sternotomy was performed, and the ascending aorta was replaced with a vascular prosthesis. Given the sefety of these procedures, we believe that securing the distal portion of the ascending aorta through an upper partial sternotomy at an early stage may be beneficial during surgery for giant ascending aortic aneurysm, as it could help avoid serious bleeding and reduce the risk of invasive strategies, such as deep hypothermia, circulatory arrest, or prolonged cardiopulmonary bypass.