[Accessory mitral valve: report of four cases and literature review].

OBJECTIVE: To describe the echocardiographic and clinical findings of patients with accessory mitral valve (AMV). METHODS: Four adult patients were diagnosed to have AMV by Doppler echocardiography. RESULTS: All the four patients had cardiac murmur but 2 were asymptomatic. Echocardiogram showed that two cases had isolated AMV with significant left ventricular outflow tract (LVOT) obstruction. Another patient was complicated by idiopathic hypertrophic subaortic stenosis and his systolic pressure gradient across the LVOT reduced to normal after taking negative inotropic drugs. The fourth patient was associated with complex congenital cardiac anomalies but without LVOT obstruction. CONCLUSIONS: AMV may not be very rare as previously reported. An echocardiographic examination can detect AMV and differentiate it from other causes of LVOT obstruction.