Comparison of haemodynamics in carotid endarterectomy: primary closure versus patch angioplasty

Abstract

We investigated differences in haemodynamic forces between carotid arteries that underwent primary closure (PC) or patch angioplasty (PA) using computational fluid dynamics (CFD). A total of 30 subjects were enrolled in this study, consisting of 10 subjects who underwent PC, 10 who underwent PA and 10 healthy subjects. Three-dimensional models of carotid arteries were reconstructed using patient-specific computed tomography angiography images. The conventional Navier-Stokes, continuity equation and constitutive stress-strain law with a stabilized Petrov-Galerkin scheme were solved with Newtonian and incompressible assumptions. The boundary conditions employed patient-specific velocity profiles as the inflow and lumped parameters of the three-element Windkessel model as the outflow with a rigid wall assumption. Thus, the CFD results exhibited good agreement with measurements from the subjects (r = .78). The carotid arteries of the PC group were exposed to abnormal haemodynamic forces related to building atherosclerosis in a smaller (p .05) to healthy arteries. The morphological characteristics of the carotid artery were significantly associated with the area exposed to abnormal haemodynamic forces. We identified that abnormal haemodynamic forces could be avoided by selecting appropriate surgical techniques that produce less bifurcation expansion.

Keywords

• Carotid endarterectomy
• haemodynamics
• computational fluid dynamics (CFD)
• wall shear stress (WSS)
• atherosclerosis
• carotid artery