TWe present the case of a 64 years old male patient who had recently suffered an infective aortic valve endocarditis (Streptococcus agalactiae) complicated by embolic arthritis of the right hip. Initial echocardiography revealed moderate aortic insufficiency developed on a tricuspid aortic valve with a small vegetation (5 mm × 4 mm) on the left coronary cusp. Furthermore, an aneurysmal dilatation of the ascending aorta (maximal diameter, 54 mm) was noted. Other heart valves and left ventricular function were considered normal. The patient completed a 4 weeks course of antibiotherapy, and the right hip arthritis was treated by drainage and synovectomy. The patient was subsequently referred to surgery on an outpatient basis for the aneurysm of the ascending aorta. Preoperative computed tomography showed localized aortic dissection of the tubular ascending aorta characterized by an intimal tear without medial hematoma but excentric bulging of the aortic wall. This lesion was initially considered a penetrating ulcer of the aortic wall The operative specimen allowed to make differential diagnosis with a penetrating aortic ulcer by showing that the lesion did not develop within an atherosclerotic plaque. However, downstream extension of the dissection was probably limited by the presence of transmural calcifications on its distal side. The patient underwent successful complete aortic root replacement using a stentless Freestyle bioprosthesis with Dacron graft extension as reported previously.