A method of assessing peripheral stent abrasiveness under cyclic deformations experienced during limb movement

Authors

Courtney Keiser, University of Nebraska-Lincoln
Kaspars Maleckis, University of Nebraska OmahaFollow
Pauline Struczewska, University of Nebraska Omaha
Majid Jadidi, University of Nebraska OmahaFollow
Jason N. MacTaggart, University of Nebraska-Medical Center,Follow
Alexey Kamenskiy, University of Nebraska OmahaFollow

Date of this Version

11-2022

Citation

Acta Biomater. 2022 November ; 153: 331–341. doi:10.1016/j.actbio.2022.09.044.

Comments

HHS Public Access.

Abstract

Poor outcomes of peripheral arterial disease stenting are often attributed to the inability of stents to accommodate the complex biomechanics of the flexed lower limb. Abrasion damage caused by rubbing of the stent against the artery wall during limb movement plays a significant role in reconstruction failure but has not been characterized. Our goals were to develop a method of assessing the abrasiveness of peripheral nitinol stents and apply it to several commercial devices. Misago, AbsolutePro, Innova, Zilver, SmartControl, SmartFlex, and Supera stents were deployed inside electrospun nanofibrillar tubes with femoropopliteal artery-mimicking mechanical properties and subjected to cyclic axial compression (25%), bending (90°), and torsion (26°/cm) equivalent to five life-years of severe limb flexions. Abrasion was assessed using an abrasion damage score (ADS, range 1–7) for each deformation mode. Misago produced the least abrasion and no stent fractures (ADS 3). Innova caused small abrasion under compression and torsion but large damage under bending (ADS 7). Supera performed well under bending and compression but caused damage under torsion (ADS 8). AbsolutePro produced significant abrasion under bending and compression but less damage under torsion (ADS 12). Zilver fractured under all three deformations and severely abraded the tube under bending and compression (ADS 15). SmartControl and SmartFlex fractured under all three deformations and produced significant abrasion due to strut penetration (ADS 20 and 21). ADS strongly correlated with clinical 12- month primary patency and target lesion revascularization rates, and the described method of assessing peripheral stent abrasiveness can guide device selection and development.