Tricuspid atresia (TA) is a rare cyanotic congenital heart disease. A persistent left superior vena cava (LSVC) may be associated with TA. The presence of LSVC raises important considerations for eventual repair, in that it may lead to persistent arterial desaturation even after corrective surgery, if associated with an unroofed coronary sinus. Here, we present the case of a 4-month-old child who was diagnosed with TA type 1B, LSVC and a dilated coronary sinus by transthoracic echocardiography.