SIGMOID SEPTUM CAUSING AORTIC REGURGITATION 1 A CASE REPORT

Abstract

An 86-year-old woman with a sigmoid septum that caused aortic regurgita- tion (AR) is described. The patient visited our hospital because of dyspnea and leg edema. On auscultation, a characteristic Levine 3/6 diastolic musical murmur was head in Erb's area. A 12-lead electrocardigram showed atrial fibrillation (heart rate=68/min) but no evidence of ischemic change. Chest radiography showed cardiomegaly but no pulmonary congestion. Two-dimensional echocardiography revealed a basal interventricular septum (IVS) markedly protruding into the left ventricular outflow tract (sigmoid septum). The angle formed by the aorta and the IVS (aorto-septal angle) was about 70 degrees. Furthermore, prolapse of the right coronary cusp toward the left ventricle accompanied by paradoxical motion of the basal IVS during diastole was also observed. Color Doppler echocardiography detected a localized and distinct regurgitant jet flow from the right coronary cusp toward the base of the anterior mitral leaflet. According to Seller's classifi- cation, the AR was grade 2. These findings suggest that AR may develop in patients with a sigmoid septum due to prolapse of the right coronary cusp leading to paradoxical motion of the basal lVS.