Cardiac resynchronization therapy defibrillator upgrade with the atrial and left ventricular leads introduction through the persistent left superior vena cava facilitated by the balloon angioplasty

The persistent left superior vena cava is the systemic venous system malformation observed in 0.1–0.5% of the general population. It can result in many obstacles in pacemaker implantation. The report presents a case of a 62-year-old male patient who underwent an upgrade of his implantable cardioverter-defibrillator to a cardiac resynchronization therapy defibrillator. The patient initially had a one- -chamber cardioverter-defibrillator implanted in 2014. Due to advanced symptomatic dilated cardiomyopathy co-existing with significant nonspecific intraventricular conduction delay, the patient was qualified for a device upgrade in 2023, i.e. implantation of additional atrial and left ventricular electrodes. The obstruction in the brachiocephalic vein and the presence of the persistent left superior vena cava were revealed in the course of the procedure. The result was a successful upgrade to cardiac resynchronization therapy defibrillator with the combination of the defibrillation right ventricular lead implanted originally through the right superior vena cava and the atrial and left ventricular electrodes implanted through the persistent left superior vena cava. The presented case describes the acceptable approach in the course of implantable cardioverter-defibrillator upgrade to cardiac resynchronization therapy defibrillator in the case of the persistent left superior vena cava and the brachiocephalic vein obstruction.