Experience with a New Epimyocardial Pacing Lead in Children

A new permanent epimyocardial Medtronic 4951 "stab-in" or "fishhook" pacing electrode was implanted in 16 children. Identical technique, with particular attention to the direction of the coronary circulation, was utilized to implant the leads. There were 10 atrial implantations (5 active, 5 redundant) and 18 ventricular implantations (15 active, 3 redundant). Pacing modes were VVI (12), VDD (1), DVI (2), and DDD (1). Experience with the lead covers 280 patient months (3 days to 21.8 months, mean 14 months). Patients were followed monthly via telephonic transmission. With the exception of the single patient who expired three days after implantation, each patient has returned for follow-up analysis including chronic threshold determinations using the programming capabilities of the pulse generators. Only one lead required more than the minimum obtainable voltage output from the pulse generator to effect capture. No other lead required more than 5.0 volts at 0.5 ms pulse width. There have been no lead fractures or dislodgements. In this evaluation the Medtronic 4951 lead performed well in both atrium and ventricle in a group of children with diverse cardiac pathology. The small diameter of the lead and the low profile of the electrode are advantageous for use in pediatric patients.