Differential pulmonary flow in hypoplastic left heart syndrome due to restrictive interatrial communication and partial anomalous pulmonary venous drainage

We report a case of hypoplastic left heart syndrome associated with restric tive interatrial communication and partial anomalous pulmonary venous conne ction via a right lower pulmonary vein draining to the inferior vena cava. We found unequal pulmonary artery pressure and different pulmonary artery s tructure, with the right pulmonary artery being lower in pressure and more tortuous and dilated in ifs peripheral branches than the left. This was att ributed to the variant degrees of pulmonary venous obstruction. The left pu lmonary venous return was severely obstructed by the restrictive interatria l communication, whereas the anomalous right lower pulmonary vein drained i nto the inferior vena cava, with less obstruction. To the best of our knowl edge there has never before been a report of differential pulmonary flow as sociated with a partial anomalous pulmonary vein, in a case of hypoplastic left heart syndrome.