冠状動脈バイパス術と僧帽弁形成術を施行した左室緻密化障害の1例

Coronary Artery Bypass Grafting and Mitral Annuloplasty in a Patient with Left Ventricular Noncompaction with Low Ejection Fraction：Report of a Case

はじめに　左室緻密化障害（LVNC）は，心室筋全層が緻密な状態に成熟せず多くの間隙が存在する心筋症である．心機能低下の主原因として心筋の冠微小循環障害が考えられ1），冠状動脈疾患による虚血が重なるとより悪影響を及ぼす．われわれは，低左心機能のLVNCが併存する冠状動脈3枝病変とtetheringによる僧帽弁閉鎖不全症に対し，冠状動脈バイパス術（CABG）と僧帽弁輪形成術（MAP）を施行し，良好な結果を得たため報告する．

A 71-year-old man who hospitalized frequently for heart failure was referred to our hospital for severe coronary disease with mitral regurgitation. Transthoracic echocardiography revealed marked left ventricular dilatation, low ejection fraction （20％） and moderate mitral regurgitation with leaflet tethering. It also revealed myocardium with prominent trabeculations and deep intertrabecular recesses. Coronary angiography showed triple vessel disease. Coronary artery bypass grafting and mitral annuroplasty was performed. Coronary microcirculatory dysfunction by left ventricular noncompaction （LVNC） and myocardial ischemia made us pay more attention to myocardial protection. Aortic cross clamp time was 67 minnutes, total cardiopulmonary bypass time was 116 minnutes and operation time was 214 minnutes. The postoperative course was uneventful and the patient was discharged 15 days after the operation. Postoperative echocardiography revealed no mitral regurgitation and improving left ventricular function. Postoperative coronary computed tomography showed all grafts patent. Careful observation of cardiac function is vital because of the possibility of progression to heart failure in a patient with LVNC.