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Cyclic velocity and acceleration of coronary arteries

The location of atheromatous plaques in arteries is closely associated to the presence of low and oscillatory wall shear stress. In order to investigate with finite elements computer techniques where oscillatory components might be present in coronary arteries, the normal physiologic movement of these vessels due to the systolic contraction and subsequent relaxation of the heart has to be taken into account because it may contribute significantly to oscillatory wall shear stress. In this contribution, the authors describe a technique developed for regional and temporal quantification of the velocities and accelerations experienced by the coronary arteries during the cardiac cycle. This method is based on 3-D reconstruction of arterial segments of interest from pairs of angiographic images and analysis of the spatial trajectories of the vessel centrelines. Feasibility results obtained with a rotating phantom and first velocity and acceleration values determined in a patient are presented.