Total anomalous pulmonary venous connection to azygos vein: echocardiographic recognition of a rare variant.

Total anomalous pulmonary venous connection to the azygos vein is a rare congenital malformation in which all the pulmonary veins drain anomalously to the azygous vein. Among 55 consecutive patients diagnosed as isolated total anomalous pulmonary venous connection by echocardiography at our institute between 1995 and January 2005, this anomaly was diagnosed in two patients. The malformation was diagnosed correctly in both the patients by echocardiography and the findings were confirmed on surgery. The importance of differentiating this condition from total anomalous pulmonary venous connection to superior vena cava by echocardiography and the differential diagnosis are discussed here.