Effect of Stent Geometry on Phase Shift between Pressure and Flow Waveforms in Stented Human Coronary Artery

Shear stress is known to play a central role in restenosis formation and is sensitive to stent geometry. Alterations of the phase shift between pressure and flow waveform created by a different stents were studied to compare the hemodynamic effects of stent design properties on restenosis in stented human coronary artery. Blood pressure waveforms were computed in three different sites, pre-stent, middle of stented arterial segment, and post-stent regions using computational fluid dynamics. Blood flow was assumed as pulsatile, incompressible, and Newtonian flow. Rigid boundary conditions were assumed for all models. The governing Navier-Stokes equations were solved using commercial software package (Fluent V6.0.12). Stents were assumed with real structure and modeled using the commercial software package (Gambit, V2.0). The alterations of the phase shift between pressure and flow waveform created by a different stents were investigated in three major regions using commercial software package (Matlab, V7.0). It is concluded that stent geometry changes the phase shift between pressure and flow waveforms in stented human coronary artery, and wall shear stress between stent struts was sensitive to these variations. The results show that variation in the phase shift is sensitive to stent geometry.