高度の左室機能低下を伴った高齢ファロー四徴症の一手術治験例

A successfully operated case of high-aged tetralogy of Fallot with marked left ventricular dysfunction

　高齢のファロー四徴症（TOF）では，心筋の脆弱性，側副血行路の発達，他の臓器合併症などのため手術のリスクが高くなるといわれている。今回我々は左室駆出分画（LVEF）が30％と高度に左室収縮能が低下した高齢TOF患者に対し根治手術をおこない，顕著な症状の改善を得たので報告する。症例は53歳男，主訴は労作時の息切れである。入院前に脳塞栓，感染性心内膜炎，髄膜炎の既往あり，いずれも治療により改善した。入院時NYHA　III度でチアノーゼ，ばち状指がみられた。心臓カテーテル検査で心室中隔欠損と50％の大動脈騎乗，肺動脈弁下狭窄を認め，右左シャントは60％，またLVEF30％と高度に低下していた。53歳と高齢で著明な左室収縮能低下を有していたが軽度の遺残短絡を残したのみで根治修復術に成功し，大きな臨床的改善が得られた。本例はこのような症例に対しても根治手術が可能で，手術により左室機能と症状の改善が期待できることを示し得た症例と考える。

Adults, especially high-aged patients with tetra-logy of Fallot (TOF) are said to have a higher operative risk than younger ones because of fragility of their myocardium, bleeding from rich collateral circulation to lungs, and other complications such as brain abscess and endocarditis. It is often difficult to determine the surgical risk for total correction in cases of high-aged patients who have such com-plications. We report a successfully operated high-aged case of TOF with marked left ventricular dys-function. A 52-year-old male was reffered to our hospital because of exertional dyspnea and cyanosis. He had a history of cerebral embolism and menin-gitis several months prior to admission. On admis-sion, he was NYHA class 3, and cyanosis and club-bed fingers were present. Cardiac catheterization showed a large VSD, 50% over-riding of the aorta and an infundibular pulmonary stenosis. Right to left shunt was 60% and Qp/Qs was 0.38. The left ventricular end diastolic volume index was 109ml/ m2, slightly larger than normal, and the ejection fraction was only 30%. This left ventricular dysfunc-tion was thought to be caused by fibrosis of the myocardium due to longstanding hypoxemia and hypoxemia itself. There is no previous case report dealing with a successful total correction for a high-aged patient with TOF associated with such a severe left ventricular dysfunction. Congestive heart failure in the post-operative period was successfully treated by catecholamine for two weeks. Post-operative cardiac catheterization showed a small left-to-right shunt, and an improvement of left venricular ejec-tion fraction from 30% to 38%. After the opera-tion, he was NYHA class 2, and had no cyanosis. This case showed that total correction is feasible even for such a high-aged, poor risk patient with TOF.