Congenital aortocaval fistula between right aortic sinus of Valsalva and superior vena cava: A rare case report.

Thoracic aortocaval fistula is a very rare cause of left to right shunt. Drainage of fistula into the superior vena cava (SVC) is very uncommon. Clinical symptoms depend on the size of the shunt. We report a rare case of an asymptomatic 27-year-old woman with congenital aortocaval fistula to the SVC with a small amount of left to right shunt that was considered for serial medical follow-up.