Horseshoe lung with left lung hypoplasia and critical pulmonary venous stenosis.

Horseshoe lung is a rare congenital anomaly characterized by an isthmus of the pulmonary parenchyma that extends posterior to the pericardial reflection at the cardiac apex and across the midline. There is unilateral, usually right-lung hypoplasia and most cases are associated with the scimitar syndrome. We present the case of an infant with horseshoe lung but with hypoplasia of the left lung and levocardia that was not associated with the scimitar syndrome.