Endovascular occlusion of right to left arteriovenous shunt associated with persistent left superior vena cava

Left-sided superior vena cava (SVC) as the result of persistence of the left superior cardinal vein in postnatal life is a rare congenital anomaly, is usually associated with other cardiac defects, and can cause symptoms of right to left shunt. We report the case of a 58-year-old Asian man with a history of end-stage renal disease and Ebstein anomaly that was corrected surgically who presented with progressively worsening disabling dyspnea. An echocardiogram with concomitant intravenous saline injection raised the suspicion of right to left shunt, a finding that was confirmed with contrast injection of the left SVC that rapidly filled the left heart chambers and subsequently the aortic arch. To treat this anomaly, we accessed the left basilic vein under ultrasound guidance and inserted a 14F sheath into the left subclavian vein. A covered stent was then prepared at the back table with three Prolene 4-0 sutures that were wrapped around the middle portion of the graft to achieve a controlled area of stenosis after deployment. The stent graft was placed along the proximal innominate vein and the contiguous part of the left SVC. Coil embolization was then performed with coils that were positioned at the stenotic area of the covered stent. An immediate venogram demonstrated residual flow into the left SVC; however, a delayed venogram 2 weeks after the procedure showed occlusion of the left SVC and the development of collaterals to the right innominate vein that was draining to a normal right SVC. The patient remained marginally hypotensive after surgery, but he soon noted a substantial improvement in his symptoms. A repeat echocardiogram with intravenous saline injection confirmed the correction of the right to left shunt. Endovascular repair of persistent left SVC is feasible and safe and can be performed with minimal morbidity.