An uncommon course of the right superior vena cava in a patient with heterotaxy syndrome

We present the case of an infant with congenital heart disease which includes a partial atrioventricular canal defect with the absence of the atrial septum (common atrium) and an extremely uncommon course of the right-sided superior vena cava (SVC) including an intra-atrial segment coursing intramurally along the right posterolateral atrial wall, with an intracardiac orifice situated low within the right side of the atrium, close to the atrial orifice of the right hepatic veins. This feature of the anatomy was discovered intraoperatively at the time of surgical repair. Systemic venous anatomy also included interrupted inferior vena cava (IVC) with azygos continuation to a left-sided SVC draining directly into the left side of the atrium. The successful surgical procedure included tunneling of the left-sided SVC to the right side of the common atrium and atrial septation with a patch.