In this condition a membrane divides the left atrium in two. The pulmonary veins are typically separated from the mitral valve. The presence of hole in the membrane ensures survival; however, when the hole is small there is severe pulmonary hypertension.
The features are those of mitral stenosis.
Diagnosis is by echocardiography.
Treatment is by excision of the membrane on cardiopulmonary bypass.
Last reviewed 01/2018