Actively adhering endocardial leads for pacing in children

Cardiac pacing in children still presents problems concerning the most favorable placement of the generator and, in particular, the growth-induced electrode complications. Whereas in infants epicardial implantation is unavoidable, one would prefer transvenous placement in older children to permit replacement or removal without extensive operative measures. The use of actively anchorable endocardial leads seems advantageous because of the possibility of placing long electrode loops in the cavity of the right atrium without increasing the risk of dislodgement. In this way overextension of the lead during growth may be avoided. Since June 1975 we have performed ventricular pacing in 10 children, aged 2 to 9 years, by using a transvenous screw-in electrode (surface 6 mm2). Acute threshold values ranged from 0.4 to 0.7 mA ap a pulse duration of 1.0 msec and sensitivity between 6.5 and 8.7 mV. Electrode function has been without complications up to now. In 6 patients we implanted programmable pacemaker systems which allowed postoperative threshold measurements. The chronic threshold value has not increased above 2.3 mA in any of these cases. In our opinion, actively anchorable endocardial leads present significant advantages for pacing in childhood.