High shear stress on the background of clinical restenosis at the site of step-down phenomenon after drug eluting stent implantation

A retrospective modeling was performed in a case with restenosis after 6 months of a DES implantation to investigate the effect of the step-down at the distal edge of the stent on the wall shear stress (WSS) using 3D coronary angiography reconstruction and the intracoronary pressure traces during a cardiac cycle. The kinetics of the WSS was calculated through the cardiac cycle along the reconstructed vessel by fluid dynamic analysis. Contrary to the previous reports the greatest amplitude and average of the arterial WSS was detected where the restenosis developed later at the site of the step-down.