INITIAL EXPERIENCE WITH A HIGH-IMPEDANCE LINED ENDOCARDIAL PACEMAKER LEAD - EVIDENCE FOR INCREASED LEAD FAILURE

We report our initial clinical experience with a new tined ventricular endocardial pacemaker lead, the Medtronic model 5034. This lead has a reduced electrode tip size, which provides a higher impedance. Based on early evidence of elevation of pacing lead threshold, we compared o ur clinical experience with the performance of this lead with that of other similar models with larger surface area (Medtronic models 4024 a nd 5024). Of 17 implant procedures performed at our institution with t he model 5034 lead, two (11.2%) developed high thresholds, versus 0% i n 121 implant procedures with models 4024 or 5024 leads (p = 0.014). W e conclude that there is evidence of increased failure caused by eleva tion of pacing threshold in this lead. This increased failure rate nee ds to be confirmed in a multicenter observational study or randomized trial.