Correlation between wall shear and intimal thickness at a coronary artery branch.

Pulsatile velocities were measured by laser Doppler anemometry at fourteen sites near the walls of a cast of a minimally diseased human left coronary artery bifurcation. The flow wave used in the experiments was physiologically realistic. The sites selected for hemodynamic measurement were at the outer walls of the left main artery and its anterior descending and circumflex branches, and along the flow divider. The intimal and medial thicknesses at corresponding sites in the original branch were also measured. Wall shear rates were derived from the velocity data. The correlations between time-average or maximum instantaneous wall shear rate and intimal thickness had negative slopes (P less than 0.005); that is, the intima was generally thicker at sites exposed to lower shears. These results are consistent with those obtained earlier using other human arterial bifurcations.