Affiliations: Mechanical Engineering Department, University of Cincinnati, Cincinnati, OH 45221, USA | Biomedical Engineering Department, University of Cincinnati, Cincinnati, OH 45221, USA | Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, USA
Note: [] Address for correspondence: R.K. Banerjee, Dept. of Mechanical, Industrial and Nuclear Engineering, 688 Rhodes Hall, PO Box 210072, Cincinnati, OH 45221-0072, USA. Tel.: +1 513 556 2124; Fax: +1 513 556 3390; E-mail: Rupak.Banerjee@UC.Edu.
Abstract: The patho-physiologic process of restenosis and tissue growth may not be completely eliminated and is the primary concern of clinicians performing angioplasty and stent implantation procedures. Recent evidence suggests that the restenosis process is influenced by several factors: (1) geometry and size of vessel; (2) stent design; and (3) it's location that alter hemodynamic parameters, including local wall shear stress (WSS) distributions. The present three-dimensional (3D) analysis of pulsatile flow in a deployed coronary stent: (1) shows complex 3D variation of hemodynamic parameters; and (2) quantifies the changes in local WSS distributions for developed flow and compares with recently published WSS data for developing flow. Higher order of magnitude of WSS of 290 dyn/cm2 is observed on the surface of cross-link intersections at the entrance of the stent for developed flow, which is about half of that for developing flow. Low WSS of 0.8 dyn/cm2 and negative WSS of −8 dyn/cm2 are seen at the immediate upstream and downstream regions of strut intersections. Persistent recirculation is observed at the downstream region of each strut cross-link and the regions of low and negative WSS may lead to patho-physiologic conditions near the stented region. The key finding of this study is that the location of stent in the coronary artery determines the developing or developed nature of the flow, which in turn, results in varied level of WSS.
