A patient with aortic valve endocarditis presented with severe aortic regurgitation, large vegetation, and a periannular cavity at transesophageal echocardiography consistent with an abscess. At surgery a common coronary ostium was found, which was responsible for the abnormal periannular image. Such congenital abnormality, although unusual, is an echocardiographic pitfall in the case of endocarditis.