Isolated persistent left superior vena cava

A persistent left-sided superior vena cava is an anatomic variation of the venous system which is seen in 0.3-0.5% of the normal population. In the absence of vena cava on the right, it is called isolated left superior vena cava and seen very rare (0.09-0.013%). It is observed in isolation but can be associated with other cardiovascular abnormalities including atrial septal defect, single atrium, ventricular septal defect, tetralogy of Fallot, coarctation of the aorta, pulmonary stenosis. The vast majority of cases are asymptomatic and diagnosed incidentally during CT scanning of the chest, or as a result of line placement. Awareness about this condition is important to avoid complications stems from central venous access, cardiothoracic surgeries, and pacemaker implantation