Incremental value of three-dimensional over two-dimensional transthoracic echocardiography in the assessment of cor triatriatum sinister in a child.

A 2.5-year-old boy presented with frequent hospitalizations due to recurrent respiratory tract infections with dyspnea. A fibromuscular membrane dividing the left atrium with obstruction of left atrial inflow to the left ventricle was documented by two-dimensional transthoracic echocardiography (2DTTE).