We report the case of a 73-year-old man with a history of previous aortic valve replacement in 1990 and rupture of an aortic dissection into the right atrium. The patient was admitted to the emergency room because of chest pain, stopped not long after. The electrocardiogram did not show any signs of ischemia and myocardial enzymes were not increased. Transthoracic echocardiography revealed aortic root dilation (maximum diameter 60 mm) extended to the aortic arch, and the presence of a flow from the ascending aorta to the right atrium (evocative of a fistula between the two chambers). The aortic valvular prosthesis function was good. Transesophageal echocardiography confirmed an aorta-right atrium fistula. Cardiac catheterization did not show any luminal obstructions in the coronary arteries; there was a small shunt from the aorta to the right atrium. The ascending aorta and the aortic root were replaced with a Dacron graft. Right and left sinuses were reimplanted to the graft. The fistula was repaired with 4-0 pledgeted Prolene sutures. The surgeon's diagnosis was "type A aortic dissection in a patient with an ascending aorta aneurysm and an old ascending aorta-right atrium fistula".