title: Hemodynamics in Idealized Stented Coronary Arteries: Important Stent Design Considerations.
abstract: Stent induced hemodynamic changes in the coronary arteries are associated with higher risk of adverse clinical outcome. The purpose of this study was to evaluate the impact of stent design on wall shear stress (WSS), time average WSS, and WSS gradient (WSSG), in idealized stent geometries using computational fluid dynamics. Strut spacing, thickness, luminal protrusion, and malapposition were systematically investigated and a comparison made between two commercially available stents (Omega and Biomatrix). Narrower strut spacing led to larger areas of adverse low WSS and high WSSG but these effects were mitigated when strut size was reduced, particularly for WSSG. Local hemodynamics worsened with luminal protrusion of the stent and with stent malapposition, adverse high WSS and WSSG were identified around peak flow and throughout the cardiac cycle respectively. For the Biomatrix stent, the adverse effect of thicker struts was mitigated by greater strut spacing, radial cell offset and flow-aligned struts. In conclusion, adverse hemodynamic effects of specific design features (such as strut size and narrow spacing) can be mitigated when combined with other hemodynamically beneficial design features but increased luminal protrusion can worsen the stent's hemodynamic profile significantly.
authors.affiliation: Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand. s.beier@auckland.ac.nz.
authors.forename: Susann
authors.initials: S
authors.lastname: Beier
authors.affiliation: Mercy Angiography, 98 Mountain Rd, Mt Eden, Auckland, 1023, New Zealand. Johno@mercyangiography.co.nz.
authors.forename: John
authors.initials: J
authors.lastname: Ormiston
authors.affiliation: Green Lane Cardiovascular Service, Auckland City Hospital, Park Rd, Auckland, 1030, New Zealand. MWebster@adhb.govt.nz.
authors.forename: Mark
authors.initials: M
authors.lastname: Webster
authors.affiliation: Faculty of Engineering, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand. j.cater@auckland.ac.nz.
authors.forename: John
authors.initials: J
authors.lastname: Cater
authors.affiliation: Faculty of Engineering, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand. s.norris@auckland.ac.nz.
authors.forename: Stuart
authors.initials: S
authors.lastname: Norris
authors.affiliation: Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand. p.medrano@auckland.ac.nz.
authors.forename: Pau
authors.initials: P
authors.lastname: Medrano-Gracia
authors.affiliation: Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand. a.young@auckland.ac.nz.
authors.forename: Alistair
authors.initials: A
authors.lastname: Young
authors.affiliation: Faculty of Medical and Health Sciences, University of Auckland, Private Bag 92019, Auckland, 1142, New Zealand. b.cowan@auckland.ac.nz.
authors.forename: Brett
authors.initials: B
authors.lastname: Cowan
mesh_terms: D003326:Coronary Circulation; D003331:Coronary Vessels / Q000503:physiopathology*; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008875:Middle Aged; D008955:Models, Cardiovascular; D011474:Prosthesis Design; D015607:Stents
keywords: Computational fluid dynamics (CFD); Coronary artery disease; Hemodynamics; Stent; Stent design; Wall shear stress (WSS)