Persistence of the left superior vena cava (
PLSVC) is a congenital anomaly reported in 0.3-0.5% of patients. Due to the multiple and complex anatomical variations, transvenous lead placement can become challenging. We report the case of a 47-year-old patient diagnosed with non-ischemic
dilated cardiomyopathy with reduced left ventricular ejection fraction (LVEF-27%), who was referred to our clinic for implantation of a dual-chamber cardioverter
defibrillator for primary prevention of
sudden cardiac death. During the procedure we encountered an abnormal guidewire trajectory and after venographic examination we established the diagnosis of
persistent left superior vena cava. After difficult implantation of a 7F defibrillation lead through the coronary sinus, we managed to place the atrial lead through a narrow brachiocephalic vein into the right atrial appendage. In this paper, we aim to illustrate the medical and technical implications of implanting a cardioverter
defibrillator in patients with
PLSVC, highlighting the benefit of identifying and utilizing both the innominate vein, and the left superior vena cava and coronary sinus for placement of multiple leads, which would otherwise have been impossible.