ATRIAL-PACING LEADS - THE CLINICAL CONTRIBUTION OF STEROID ELUTION

Although the original atrial pacing leads were passive fixation and J shaped for right atrial appendage placement, the subsequent development of the active fixation screw-in lead found favor because of a perceived low incidence of lead dislodgment and a wider selection of atrial pacing sites. A bipolar atrial lead study was undertaken to compare the long-term atrial implant data in 225 patients. Study leads comprised one passive fixation, steroid-eluting lead (Medtronic CapSure(R) SP, 119 patients) and three nonsteroid-eluting leads; two active fixation (Medtronic BISPING(R) model 4058, 30 patients; and Telectronics ACCUFIX(R) model 330-801, 44 patients) and one passive fixation (Telectronics ENCOR(R) model 330-854, 22 patients). Bipolar atrial voltage stimulation thresholds and electrograms were measured using the Telectronics META(R) DDDR immediately postimplantation, and at 1-, 3-, 6-, 22-, and 18-month follow-up. There were 135 males and the mean age 68 years. The incidence of lead dislodgment was 4% for active fixation and 2% for passive fixation. All nonsteroid leads showed a typical rise in stimulation thresh old with the highest being the ACCUFIX followed by the BISPING and ENCOR. The steroid-eluting CapSure SP, however, demonstrated a flat response with 98% of leads at 18 months having a value less than or equal to 1.3 volts allowing voltage programming to 2.5 volts (2:1 safety ratio). Telemeted electrograms showed no differences for all leads at all visits. For low voltage atrial pacing with a low incidence of dislodgment and satisfactory atrial sensing, the steroid-eluting passive fixation lead is superior to all nonsteroid-eluting leads.