VDD pacing from the middle cardiac vein via a persistent left superior vena cava

We report a combination of unusual features demonstrating a permanent pacem aker implantation of a single-pass VDD lead by way of an anomalous persiste nt left superior vena cava in the middle cardiac vein. The ventricular stim ulation resembled a right bundle branch block QRS morphology and was succes sfully synchronized by spontaneous atrial activity. This case illustrates a n alternative approach of effective VDD pacing and sensing in patients with such a venous anomaly when other standard implantation sites fail.