A 39-year-old man with fever and dyspnea from 3 days earlier was taken to the emergency room. He was diagnosed with infective endocarditis because echocardiography showed a mobile 10 mm-sized vegetation on the aortic valve and severe aortic regurgitation. Acute coronary syndrome was negative because the tests at the first visit did not show an increase in myocardial deviation enzymes or a decrease in wall motion. However, his hemodynamics deteriorated during the same day, so he underwent emergency surgery. The left and right leaflets and the right aortic annulus were highly destroyed, and the aortic annulus was reconstructed with his pericardium and the valve was replaced by a mechanical valve. After declamping of the aorta, the wall motion of the left ventricle was extremely reduced, and the cardiopulmonary bypass(CPB) was not able to be withdrawn. Since the left anterior descending (LAD) coronary artery may have been occluded by vegetation, we added bypass surgery to the LAD under cardiac arrest using a saphenous vein graft. After the bypass surgery, the wall motion of the left ventricle improved, and we were able to withdraw the CPB. Though he developed a cerebral infarction as a complication and required long-term rehabilitation, he was able to be discharged from the hospital 74 days after the operation. We evaluated the coronary arteries after his discharge and found an occlusion that was thought to be due to vegetation scattered in the LAD. No preoperative coronary artery evaluation was performed, however, the graft was anastomosed to the distal side of the LAD occlusion. Currently, 3 years and 2 months have passed and the infection has not recurred.