突然の胸痛で発症した早期生体弁機能不全の1例

Sudden Chest Pain due to Early Bioprosthetic Valve Dysfunction：Report of a Case

はじめに　生体弁による大動脈弁位人工弁置換術は，高齢者の重症大動脈弁狭窄症に対する治療の第一選択である．生体弁の耐久性が改善され，中長期にわたる経過についてはおおむね満足できるものとなっている．しかし，生体弁構造が破壊されることで急性閉鎖不全を生じ，血行動態が保てなくなり，すみやかな治療介入を要することもある．われわれは，明らかな誘因なく生体弁弁尖に亀裂が入り，突然の胸痛で発症した急性大動脈弁位生体弁閉鎖不全に対し，再弁置換術を行い救命しえたので報告する．

We report a case of bioprosthetic valve dysfunction and acute aortic valve regurgitation. The case was a 75-year-old female who had sudden onset chest pain. ST-segment depression in several leads on electrocardiogram （ECG） suggested acute coronary syndrome. Coronary angiography showed no significant stenosis in coronary arteries. Transesophageal echocardiography revealed severe aortic regurgitation, suggesting that angina was caused by myocardial ischemia associated with acute aortic regurgitation. She was diagnosed as having bioprosthetic valve dysfunction, and underwent redo aortic valve replacement. One leaflet of the bioprosthetic valve was torn along the stent post and caused bioprosthetic valve dysfunction. Failed bioprosthetic valve was removed and replaced by a mechanical valve.