Isolated Persistent Left Superior Vena Cava Causing Hemodialysis Catheter Dysfunction: An Uncommon Challenge in Vascular Access.

A persistent left superior vena cava (PLSVC) is the most common congenital anomaly of the thoracic venous system. Complete absence of the right superior vena cava (SVC) is rare but may complicate central venous catheter placement and hemodialysis access if unrecognized. We report the case of a 76-year-old man with dilated cardiomyopathy, heart failure with reduced ejection fraction, and end-stage kidney disease who was admitted with volume overload and metabolic acidosis requiring urgent hemodialysis. A tunneled central venous catheter inserted via the right internal jugular vein showed an atypical leftward guidewire course on fluoroscopy, and digital subtraction angiography revealed a PLSVC. Computed tomography angiography confirmed a large-caliber PLSVC draining into a markedly dilated coronary sinus with complete absence of a right-sided SVC. Based on these findings, vascular access was re-established via the left internal jugular vein with the catheter positioned deeper to ensure correct placement, which restored effective dialysis flow. This case underscores that an isolated PLSVC, although uncommon, can significantly affect vascular access procedures. Early recognition of an atypical guidewire trajectory and prompt imaging are essential for safe and functional hemodialysis catheter placement.