Résumé : A 56-day old baby girl referred for recurrent respiratory tract infections and stridor, showed a rare association of a Cor Triatriatum Sinister (CTS) and a right Partial Anomalous Pulmonary Venous Return (PAPVR), in the form of a stenosed Scimitar vein, draining the right pulmonary veins to the subdiaphragmatic inferior vena cava (IVC), on echography and angiography. The baby underwent successful surgical repair of the CTS, by resection of the obstructive false membrane and reconnection of the Scimitar vein to the left atrium. At the age of 5 years, the child is doing well without any evidence of obstruction on the right or the left pulmonary venous drainage.