Permanent cardiac pacing in a patient with persistent left superior vena cava and concomitant agenesis of the right-sided superior vena cava.

Persistent left superior vena cava (PLSVC) can be incidentally detected during pacemaker implantation from the left pectoral side. Optimal site pacing is technically difficult, and lead stability of the right ventricle (RV) can lead to such a situation. We describe a case of successful single-chamber pacemaker implantation in a 76-year-old woman with a PLSVC and concomitant agenesis of the right-sided superior vena cava, after failed attempts with the conventional procedure. The pacemaker had been working well after 12 months of follow-up.