Introduction: Persistent left superior vena cava (PLSVC) is a venous anomaly with an incidence around 0.5% in the general population. It is often discovered incidentally during vascular surgeries or in critical care settings during central line placement. It is essential for intensivists to be aware of this anomaly and its complications. We present two cases of PLSVC variations incidentally found during left sided central venous cannulation and our approach to verify the diagnosis and evaluate for complications. Description: Case 1 is a 37-year-old male with end-stage renal disease, who presented with encephalopathy and was admitted for emergent dialysis. The patient decompensated warranting placement of a left internal jugular (IJ) central line. The procedure was uncomplicated; however chest x-ray showed the line coursing along the left heart border. A central venous waveform and blood gas was confirmed. A bedside echocardiogram showed a dilated coronary sinus and no shunt. The line was ultimately removed due to thrombus potential. Case 2 is a 26-year-old male who presented in a sickle cell crisis. An echocardiogram showed concerns for cardiogenic shock, so a left subclavian pulmonary artery catheter was inserted. A central venous waveform was present at 45cm, but it was not able to be wedged. The line was left in place while a right IJ catheter was inserted and successfully wedged. A chest x-ray confirmed the normally positioned right IJ catheter and the left subclavian line coursing down the left hemithorax and terminating at the right atrium. The assessment of bilateral SVC was made, and the left catheter was removed. Discussion: PLSVC is a congenital anomaly that arises from persistence of the left anterior cardinal vein. PLSVC can be asymptomatic, however some can drain into the left atrium causing right to left shunt physiology. PLSVC can occur with co-existing right-sided SVC as well as less commonly in the absence of a right-sided SVC. Catheter placement into the dilated coronary sinus may lead to complications; however, case reports have shown safe use of these vessels. Further investigation should determine where the vessel terminates and complications such as presence of a shunt. We aimed to show our approach to confirm the finding and potential complications in these two cases.
Gonzalez et al. (Sun,) studied this question.