Possible Benefits of Catheters With Lateral Holes in Coronary Thrombus Aspiration: A Computational Study for Different Clot Viscosities and Vacuum Pressures

Abstract

According to a number of clinical studies, coronary aspiration catheters are useful tools to remove a thrombus (blood clot) blocking a coronary artery. However, these thrombectomy devices may fail to remove the blood clot entirely. Few studies have been devoted to a systematic analysis of factors affecting clot aspiration. The geometric characteristics of the aspiration catheter, the physical properties of the thrombus, and the applied vacuum pressure are crucial parameters. In this study, the aspiration of a blood clot blocking a coronary bifurcation is computationally simulated. The clot is modeled as a highly viscous fluid, and a two-phase (blood and clot) problem is solved. The effects of geometric variations in the tip of the coronary catheter, including lateral hole size and location, are investigated considering different aspiration pressures and clot viscosities. A Bird-Carreau model is adopted for blood viscosity, while a power law model is used to describe the clot rheology. Computational results for blood clot aspiration show that the presence of holes in the lateral part of the tip of the catheter can be beneficial depending on clot viscosity, hole features, and applied aspiration pressure. In general, the holes are beneficial when the clot viscosity is low, while aspiration catheters without any extra lateral holes exhibit better performance for higher clot viscosity. However, when higher aspiration pressures are applied, the catheters tend to behave relatively similarly in removing clots with various viscosities, reducing the role of the clot viscosity.

Three‐Dimensional Numerical Simulations of Aspiration Process: Evaluation of Two Penumbra Aspiration Catheters Performance

“…In order to simulate the hemodynamic situation in the occluded middle cerebral artery, 10 kPa pressure is set at inlet 1 and 2 . The vacuum pressure applied to the tip of the catheter is reduced along the catheter.…”

“…Two‐phase flow was adapted to model the clot as a viscous fluid immersed in fluid phase of blood. In this model, Newtonian and non‐Newtonian models (power law) were chosen to describe clot rheology. In this study, the relation between geometric parameters of the aspiration catheter, rate of the aspirated clot, time of aspiration, the age of thrombus, and suction pressure was analyzed .…”

“…In this model, Newtonian and non‐Newtonian models (power law) were chosen to describe clot rheology. In this study, the relation between geometric parameters of the aspiration catheter, rate of the aspirated clot, time of aspiration, the age of thrombus, and suction pressure was analyzed . Furthermore, a numerical framework was developed by Neidlein et al to investigate the flow pattern of the Circle of Willis (CoW) during aspiration in acute stroke.…”

Artificial Organs 2014: A Year in Review

“…Sajjad Soleimani et al. of the Politecnico di Milano, Milan, Italy, evaluated the benefits of catheters with lateral holes in coronary thrombus aspiration. The aspiration of a blood clot blocking a coronary bifurcation was computationally simulated.…”

Performance of a thrombectomy device for aspiration of thrombus with various sizes based on a computational fluid dynamic modeling

“…Moreover the thrombectomy aspiration catheter along with the blood thrombus were located at the bifurcation area of the vessel. A more realistic thrombus mechanical characteristic regarding the viscosity of the thrombus was applied [13]. In the current study we follow the more recent approach [13] and the CFD method is used to investigate the behaviour of thrombectomy aspiration devices in the presence of thrombus with various sizes.…”