Assessment of Coronary Artery Geometry With Coronary CT Angiography: Evaluation of Atherosclerotic Plaque Burden and Composition

The angulation of the side branch take-off has been reported to influence the severity of atherosclerosis in coronary bifurcations, as larger angles have been associated with increased plaque burden. Data from computational fluid dynamics studies have confirmed this finding by demonstrating that even in the absence of alterations in the amount of branch flow, a wide angle between the side branches intensifies flow perturbations, increases the spatial endothelial shear stress (ESS) variations in the bifurcation region and the low ESS in the lateral walls, thereby augmenting the atherosclerosis-prone environment. The magnitude of reversed flow, the extension of the recirculation zone and the duration of flow separation during the pulse cycle comprise other haemodynamic parameters which are important in atherogenesis and are amplified by an increased bifurcation angle.