Chronic cyanosis due to persistent left superior vena cava draining into the left atrium in the absence of a coronary sinus.

We report a rare case of a 5-year-old child who presented with chronic hypoxemia and a normal cardiac examination, and was found to have a persistent left superior vena cava draining directly into the left atrium. The coronary sinus was absent. This case introduces a contradiction to the generally accepted concept that this anomalous connection can only occur in the presence of a partly or completely unroofed coronary sinus. High index of suspicion is required to include this pathology in the differential diagnosis for a patient with persistent cyanosis with normal cardiac examination.