title: Simulation of mechanical environment in active lead fixation: effect of fixation helix size.
abstract: The risk of myocardial penetration due to active-fixation screw-in type pacing leads has been reported to increase as the helix electrodes become smaller. In order to understand the contributing factors for lead penetration, we conducted finite element analyses of acute myocardial micro-damage induced by a pacemaker lead screw-in helix electrode. We compared the propensity for myocardial micro-damage of seven lead designs including a baseline model, three modified designs with various helix wire cross-sectional diameters, and three modified designs with different helix diameters. The comparisons show that electrodes with a smaller helix wire diameter cause more severe micro-damage to the myocardium in the early stage. The damage severity, represented by the volume of failed elements, is roughly the same in the middle stage, whereas in the later stage the larger helix wire diameter generally causes more severe damage. The onset of myocardial damage is not significantly affected by the helix diameter. As the helix diameter increases, however, the extent of myocardial damage increases accordingly. The present findings identified several of the major risk factors for myocardial damage whose consideration for lead use and design might improve acute and chronic lead performance.
authors: Department of Biomedical Engineering, Indiana University-Purdue University Indianapolis, Indianapolis, IN 46202, USA.
authors: Xuefeng
authors: X
authors: Zhao
authors: Jonathan F
authors: JF
authors: Wenk
authors: Mike
authors: M
authors: Burger
authors: Yi
authors: Y
authors: Liu
authors: Mithilesh K
authors: MK
authors: Das
authors: William
authors: W
authors: Combs
authors: Liang
authors: L
authors: Ge
authors: Julius M
authors: JM
authors: Guccione
authors: Ghassan S
authors: GS
authors: Kassab
mesh_terms: D001696:Biomechanical Phenomena; D001698:Biomedical Engineering; D003198:Computer Simulation; D017147:Defibrillators, Implantable / Q000009:adverse effects; D004567:Electrodes, Implanted / Q000009:adverse effects; D004867:Equipment Design; D020342:Finite Element Analysis; D006335:Heart Injuries / Q000209:etiology; D006801:Humans; D008955:Models, Cardiovascular; D010138:Pacemaker, Artificial / Q000009:adverse effects; D012307:Risk Factors