Clinical surveillance of a tined, bipolar, J-shaped, steroid-eluting, silicone-insulated atrial pacing lead

Since 1990, 558 Medtronic 5524 bipolar, silicone-insulated, J-shaped, fined , steroid-eluting atrial leads have been implanted at the Mayo Clinic (Roch ester, MN, USA) and the Midelfort Clinic (Eau Claire, WI, USA). Implantatio n data were favorable, with pacing thresholds at implantation (median thres hold, 0.6 V) better than most published data on other atrial leads. The rat e of acute lead-related complications (dislodgment and diaphragmatic pacing ) necessitating reoperation or electrical abandonment of the atrial lead wa s 0.9%. This rate is lower than that in most published series of atrial lea ds. Over a median follow-up time of 17.5 months (up to 69 months), there we re no chronic lead-related complications and no definite or suspected failu res of lead material. This rate is much lower than that with other atrial l eads studied previously. We conclude that the Medtronic 5524 atrial lead co mbines the reliability of silicone insulation with a lack of chronic compli cations and high thresholds due to its steroid elution and with stability i n the atrium due to ifs J shape despite a passive fixation mechanism. There is no evidence of lead material failure during up to 6 years of follow-up.