AbstractA 56-year-old man, suspected of having ST-segment elevation myocardial infarction due to spontaneous coronary artery dissection, underwent emergency percutaneous coronary intervention. Although he had moderate aortic regurgitation with aortic root dilation and mild heart failure, it was controlled with medications. Two weeks after discharge, he was readmitted with severe heart failure due to severe aortic regurgitation and underwent an aortic root replacement. Intraoperative findings revealed that localized dissection of the sinus of Valsalva involved the right coronary artery, resulting in coronary artery dissection. In cases of spontaneous coronary artery dissection, attention should be paid to coronary artery dissection caused by localized aortic root dissection.