Computation of hemodynamics in eccentric coronary stenosis: A morphological parametric study.

Abstract

Flow recirculation occurs in eccentric coronary stenosis, which can lead to adverse outcome. The complex local geodesic patterns of eccentric stenosis are critical factors in determining the flow characteristics in post-stenotic flow. The main objective of this study is to relate the relationship between the detailed morphological parameters in eccentric coronary stenosis and the post-stenotic flow characteristics. Several idealized eccentric coronary stenosis models with variable morphological parameters are created to conduct a series of computational fluid dynamics analysis. The impact of four specific lesion morphological parameters, eccentricity index (EI), diameter stenosis (DS), stenosis length (SL) and shape of lesion, are investigated. When EI is small (< 0.33), the length of recirculation zones would increase as EI increase; while when EI is large (> 0.33), it would decreased as EI increase; Larger magnitude of retrograde flow occurs in models with smaller EIs. Both the recirculation zone length and maximum shear rate increase significantly as DS increases. Increase of SL will lead to increase of recirculation zone length. Higher maximum shear rate and larger recirculation zone are observed in models with sharper stenosis shape. Except DS, the detailed geometry patterns (EI, SL and shape of the stenosis) also have great impact on post-stenotic flow behaviors in eccentric coronary stenosis.