Diagnosis of inferior sinus venosus atrial septal defects using transthoracic three-dimensional echocardiography.

The authors report the cases of 2 patients with symptoms and signs related to severe pulmonary hypertension. Two-dimensional echocardiography demonstrated defects in the posterior portion of the atrial septum. Transthoracic three-dimensional echocardiography clearly showed inferior sinus venosus atrial septal defects and their relationships with the inferior vena cava, the pulmonary vein, and the muscular border of the fossa ovalis. These 2 cases not only elucidate the potential value of transthoracic three-dimensional echocardiography in delineating the structural characteristics of unusual interatrial shunting but also remind clinicians to be aware of this potentially treatable cardiac defect during workup for pulmonary hypertension.