Does the Difference in Realistic Waveform Before and After Stenting Affect Hemodynamics in Stenosed Coronary Artery?

Abstract

Vascular hemodynamic forces influence the focal development of atherosclerosis. Atherogenesis has been linked to low and oscillating wall shear stress (WSS) driven by the pulsatile nature of blood flow [1, 2]. Strong evidence has emerged that time-averaged WSS (TAWSS) and oscillating shear index (OSI) are important measures of the atherogenic nature of blood flow. Recently it was reported that the phase-angle between oscillating WSS and circumferential strain in arterial wall (stress phase angle: SPA) may also influence endothelial cell function and contribute to atherosclerosis [3]. In stenosed, curved or bifurcated arteries, the blood flow pattern is complex because of flow separation, which is highly sensitive to the local velocity waveform [4]. Although the effects of waveform on coronary blood flow has been studied by comparing physiological and idealised waveforms [5], the effects of variation in physiological waveforms and their impact on SPA are still unclear. In this study we investigated computationally the influence of physiological flow velocity and pressure waveforms on coronary hemodynamic parameters (e.g. TAWSS, OSI and SPA) using waveforms acquired before and after coronary artery stenting.