Purpose: In-stent restenosis (ISR) is related to local haemodynamics in the arteries after stent intervention. However, the haemodynamics of stents implanted into tapered vessels is rarely studied and remains unclear. This study aimed to study the haemodynamic performance of a stent in a tapered artery to reveal the haemodynamic differences between tapered and cylindrical stents after stent implantation and guide the stent selection for the treatment of coronary artery stenosis.
Methods: Cylindrical and tapered stents were implanted into the tapered arteries. A model of a cylindrical stent implanted into a cylindrical artery was established as the contrast model. Using the finite element method, the flow velocity and wall shear stress distribution of the three models were compared.
Results: At t1, t2, t3 and t4, the flow rate of the tapered artery with tapered stents (TT) after the implantation increased by 8.59, 3.80, 12.81 and 3.66%, respectively. In addition, the wall shear stress in the tapered arteries of TT was 23.48, 36.67, 13.00 and 8.06% higher than that of the tapered arteries with cylindrical stents (TC).
Conclusions: The implantation of a tapered stent in the tapered artery can effectively improve intravascular haemodynamics. The tapered stent allows the tapered artery to obtain better haemodynamics and reduces the probability of ISR.
Keywords: Cylindrical stent; Haemodynamics; Numerical simulation; Tapered arteries; Tapered stent.