Partial anomalous pulmonary venous connection with anomalous connection of the superior vena cava to the left atrium

Abstract

Partial anomalous pulmonary venous connection (PAPVC) is a very rare congenital anomaly that was first described by Winslow in 1789. Pathologic studies suggest that this anomaly occurs in 0.7% of the population, which is a higher rate than reported in clinical series. Most cases are associated with a sinus venosus defect. PAPVC from the right lung is twice as common as PAPVC from the left lung. Most commonly, the anomalous connection is to the right superior vena cava (SVC) or the right atrium. Isolated PAPVC with intact atrial septum is even less common and usually involves drainage of the right upper pulmonary vein into the SVC. In this report, we present a case in which preoperative echocardiography suggested a superior sinus venosus atrial septal defect with anomalous drainage of the right upper lobe to the SVC. Intraoperatively, no atrial septal defect was found. An anomalous vessel was attached to the SVC at the level of multiple small anomalous right upper pulmonary veins to the SVC and was connecting the SVC to the roof of the left atrium. Surgical correction was established by disconnection of the right PAPVC and the anomalous vessel from the SVC, with reconstitution of the SVC by direct anastomosis.