We report the case of acquired left ventricle (LV) to right atrial (RA) communication through an aneurysm of the atrioventricular septum caused by infectious endocarditis. A severe aortic valve regurgitation and destruction of the aortic valve was detected by echocardiography. Transesophageal echocardiography revealed a flail aortic valve with vegetation and abnormal shunt flow from the LV to RA with ruptured aneurysm of the membranous septum. An abscess cavity of the aortic ring was introduced. Because of worsening congestive heart failure, the patient underwent emergency aortic valve replacement and patch closure of the communication of the membranous septum. The patient's postoperative course was uneventful.
Keywords: Aortic root abscess; Infective endocarditis; LV–RA communication; Perforation of an aneurysm of the atrioventricular septum.