Cor triatriatum. Diagnosis by echocardiography.

A case of cor triatriatum is reported in which the left atrial diaphragm was shown by a preoperative echo-cardiogram, but not by angiocardiography. Echocardiography may be a useful diagnostic procedure in this uncommon form of congenital heart disease. Cor triatriatum can be readily corrected surgically. Adult patients present with signs of pulmonary venous and arterial hypertension, and the condition must be distinguished from mitral valve disease which it closely resembles and from less common left-sided obstructive lesions. Though some of the characteristic clinical, radiological, and electro-cardiographic signs of mitral stenosis may be absent, the distinction is usually made preoperatively by angiocardiography, or occasionally by recording a low left atrial pressure distal to the obstructing diaphragm.