Unexpected persistent left superior vena cava and absent right superior vena cava in situs solitus patient.

We, herein, report a patient with persistent left superior vena cava with enlarged coronary sinus and absent right superior vena cava. This anomaly, diagnosed intraoperatively during the third open-heart surgery in the course of transesophageal echocardiography examination, was not mentioned during the patient's previous two cardiac operations. Challenges in intraoperative management and implications for subsequent treatments are discussed.