Accessory mitral valve associated with aortic and mitral regurgitation and left ventricular outflow tract obstruction in an elderly patient: a case report.

A 65-year-old man was admitted to our hospital because of exertional dyspnea. Transthoracic and transesophageal echocardiography showed a parachute-like structure measuring 20 x 16 mm, which projected into the left ventricular outflow tract (LVOT) and passed through the aortic valve in systole, and prolapsed back into the left ventricular cavity in diastole. Moderate aortic and mitral regurgitation were also observed, as well as LVOT obstruction with a peak gradient of 30 mmHg. There were no other congenital cardiac abnormalities. In addition, real-time three-dimensional transthoracic echocardiography showed that the parachute-like structure in the LVOT was attached to the anterior mitral leaflet and left ventricular lateral wall by a chorda tendineae-like structure. The diagnosis of accessory mitral valve was based on the echocardiographic characteristics. Surgical treatment was performed because of the presence of accessory mitral valve, moderate aortic and mitral regurgitation, and LVOT obstruction. The postoperative course was uneventful, and the patient has been asymptomatic during a follow-up period of 24 months. Echocardiographic examination proved to be useful for the detection of accessory mitral valve.