A 54-year-old man with a history of chest pain and dyspnea for 15 days was admitted to our hospital. Diagnostic evaluation, which included transthoracic echocardiography and computed tomographic scanning, revealed an ascending aortic aneurysm (6 cm in diameter), severe aortic valve insufficiency, and possible aortic dissection. The coronary arteries could not be seen, because the catheter could not be placed in their orifices. The patient was taken to the operating room. Intraoperative transesophageal echocardiography revealed an intimal flap in the ascending aorta. The proximal part of the flap was attached to the aortic wall at the level of the coronary Ostia, and its distal part was circumferentially free (Fig. 1). The flap was prolapsing into the left ventricular outflow tract through the aortic valve leaflets at every diastole (Fig. 2A) and moving back to the aortic lumen at systole (Fig. 2B). The patient underwent aortic root replacement by means of the Bentall procedure. During surgical exploration, we saw that the dissection involved the commissures and the orifice of the right coronary ostia and that it ended just proximal to the aortic clamp, which did not necessitate the use of hypothermic circulatory arrest (Fig. 3). The patient was discharged from the hospital 6 days after the operation without complication.