STEROID ELUTION IMPROVES THE STIMULATION THRESHOLD IN AN ACTIVE-FIXATION ATRIAL PERMANENT PACING LEAD - A RANDOMIZED, CONTROLLED-STUDY

Background Prior work suggests that the addition of a steroid-eluting reservoir to a passive-fixation permanent pace maker lead improves the stimulation threshold; however, no large randomized study has address ed this issue. Over the last several years, there has been an increase in enthusiasm for the use of active-fixation permanent pacemaker lead s for various reasons in spite of the generally accepted notion that a ctive-fixation leads have higher stimulation thresholds. Methods and R esults This multicenter, randomized, controlled study examined the dif ference in performance between a standard active-fixation atrial lead (Medtronic model 4058) and a steroid-eluting lead (Medtronic model 406 8). Stimulation thresholds were obtained in a four-point strength-dura tion fashion. Evaluations of sensing and impedance were performed as w ell. These evaluations were performed at implantation, at weeks 1 thro ugh 4, and at weeks 6, 12, 24, and 52. Stimulation thresholds were sig nificantly better in the steroid lead than in the nonsteroid lead at e ach measurement point from 1 week to 12 months. The mean 1.6-V stimula tion threshold at 12 months was 0.19+/-0.2 ms in the steroid lead and 0.41+/-0.30 ms in the control lead. No acute peaking was observed with the steroid lead, whereas significant peaking was observed with the c ontrol lead. There was no difference in long-term sensing or impedance . Conclusions Inclusion of a steroid-eluting reservoir in an active-fi xation permanent pacing lead improved stimulation thresholds in both t he subacute and chronic periods and therefore should extend pulse-gene rator longevity.