Implantation of pacemaker for sick sinus syndrome in a patient with persistent left superior vena cava and absent right superior vena cava.

Absent right superior vena cava with persistent left superior vena cava in normal situs is an exceedingly rare congenital anomaly. In such cases, pacemaker implantation (PMI) is very difficult or even impossible. We report the case of a patient with sick sinus syndrome in whom PMI was easily performed via the left superior vena cava by using a steerable stylet.