Abstract
Isolated persistent left superior vena cava (PLSVC) is a very rare congenital thoracic venous system anomaly and is commonly an incidental finding, usually detected during central venous access, cardiac catheterization, or cardiothoracic surgeries. This is a rare case report wherein the patient is a known case of ischemic heart disease with s/p percutaneous transluminal coronary angioplasty (PTCA) with a stent to left anterior descending (LAD) artery with in-stent re-stenosis presented with complete heart block and had an unanticipated discovery of isolated PLSVC on facing difficulty during the transvenous approach of permanent pacemaker implantation (PPI). In this case report, we inspect the challenges associated with and various clinical implications of isolated PLSVC.