The Influence of Endocardial Electrode Fixation Status on Acute and Chronic Atrial Stimulation Threshold and Atrial Endocardial Electrogram Amplitude

Abstract

(1) A significantly higher endocardial PWA occurs at the time of lead implantation in nonscrew versus screw-in lead groups, but the chronic PWA does not differ between the two groups. (2) A transient but marked early (mean approximately 31 days) attenuation of the PWA occurs only with nonscrew-in leads. (3) Atrial threshold stimulation energies do not differ between the two lead groups acutely or during follow-up.

European Clinical Experience with a Dual Chamber Single Pass Sensing and Pacing Defibrillation Lead

“…In comparison to single pass VDD pacing leads and additional active or passive atrial fixation pacing leads without steroid elution, comparable atrial sensing values could be achieved with the atrial electrode of the quadripolar lead, which also had no steroid deposit. [26][27][28] However, single atrial leads with a steroid deposit demonstrated somewhat better sensing values independently of the fixation mode. 29,30 Nevertheless, an improved cardiac output, stroke volume, and maximal oxygen uptake could be achieved comparing VDD pacing to VVIR pacing in patients with an AV conduction disease and a normal left ventricular function.…”

Covalent surface chemical modification of electrodes for cardiac pacing applications

“…As for most steroid-free electrodes, an increase in stimulation threshold was observed within days after pacemaker implantation, subsiding typically within the first 2-3 weeks. This rise in stimulation threshold was a direct result of inflammation at the electrode-tissue interface, 20,21 and common for active-fixation electrodes. The fixation mechanism for screw-helix electrodes was highly traumatic; tissue disruption and injury were an intrinsic and necessary part of implantation.…”

“…Comparison of the threshold behavior of control noble metal electrodes with the behavior of the experimental Au-dodecanethiol group showed certain striking differences in both the early and chronic phases of pacing. Episodes of early phase increase in stimulation threshold to Ն0.4 ms (the value at which surveillance would be intensified in humans 18,[20][21][22] ) at 2.5 V amplitude output were observed in only one of the four experimental Au-dodecanethiol electrodes (excluding the one with mechanical microdislodgement) but in six of seven controls (p ∼ .08). Severe threshold rises to ±1.0 ms were observed in none of four such experimental but in four of seven noble metal control electrodes.…”