Partial or total anomalous pulmonary venous drainage caused by malposition of septum primum: echocardiographic description of a rare variant of anomalous pulmonary venous drainage.

We describe the echocardiographic findings in 9 patients, a rare variant of partial and total anomalous pulmonary venous drainage directly to the morphologic right atrium, caused by malposition of septum primum. Displacement of septum primum to the morphologic left atrium was present in all 9 cases leading to partial or complete anomalous drainage of pulmonary veins to the morphologic right atrium. However, all pulmonary veins were connecting normally to the morphologic left atrium. The views that best demonstrated the deviation of septum primum were subxiphoid coronal, apical 4-chamber, and parasternal long-axis.