10. 上行大動脈置換術後大動脈弁閉鎖不全に対する手術

Operation for Aortic Regurgitation after Replacement of Ascending Aorta

大動脈弁閉鎖不全（AR）の病因として，大動脈弁異常と大動脈基部拡大の二つがある．弁異常によるARの原因には，加齢変性，感染性心内膜炎による弁破壊，リウマチ性，弁尖逸脱，心室中隔欠損症に伴う弁の嵌入，外傷などがある．また，大動脈基部拡大によるARの原因には，大動脈弁輪部拡張症，遺伝性大動脈疾患（Marfan症候群，Loeys-Dietz症候群，血管型Ehlers-Danlos症候群など），高血圧，自己免疫疾患（全身性エリテマトーデス，強直性脊椎炎，Reiter症候群），大動脈解離などがある1）．この中でも，上行大動脈置換術後に手術適応となるARをきたしやすい疾患として，急性大動脈解離や結合組織疾患が考えられる．

It is not uncommon for aortic regurgitation to occur after ascending aortic replacement. There are various causes of the aortic valve insufficiency after ascending aorta replacement. Among them, most common is a reoperation after open repair of Stanford type A acute aortic dissection. Although it is becoming safer to perform reoperative cardiac surgery, the risks of operative mortality and morbidity is still higher than those of non-reoperative cardiac surgeries. In order to improve the mortality and morbidity rate, we should select the best strategies with a thorough preoperative evaluation. Moreover, a careful observation after the operation is required to find the complications, especially the patients who have the risk of aortic valve insufficiency.