右冠状動脈左冠状動脈洞起始症に対する右冠状動脈起始部形成術

Anomalous Origin of the Right Coronary Artery from the Left Sinus of Valsalva Treated with Modified Unroofing Procedure

右冠状動脈左冠状動脈洞起始症（AAORCA）は先天性冠状動脈異常の一つである．われわれはAAORCAに対して右冠状動脈（RCA）起始部形成術（modified unroofing）を施行した1例を経験したため報告する．

We report a case of a 50-year-old man with anomalous aortic origin of the right coronary artery （AAORCA） and hypertrophic obstructive cardiomyopathy （HOCM）, who was treated with modified unroofing and septal myectomy. The patient presented with exertional syncope. Echocardiography revealed systolic anterior motion （SAM）-associated severe mitral regurgitation （MR） and HOCM. Coronary computed tomography （CT） showed AAORCA with an inter-arterial course and occlusion of the left anterior descending artery （LAD）. Intraoperative findings confirmed intramural segment of the anomalous coronary artery was near the commissure of the aortic valve. To preserve native aortic valve function, modified unroofing technique was employed to establish a new right coronary ostium. Septal myectomy was performed to relieve left ventricular outflow tract obstruction, and coronary artery bypass grafting using the left internal thoracic artery was conducted to revascularize the LAD. Postoperatively, myocardial ischemia was resolved, and MR disappeared. The patient was discharged on postoperative day 10 without complications and has remained free of syncope during three years of follow-up.