Hemodynamic analysis of sequential graft from right coronary system to left coronary system

Abstract

BackgroundSequential and single grafting are two surgical procedures of coronary artery bypass grafting. However, it remains unclear if the sequential graft can be used between the right and left coronary artery system. The purpose of this paper is to clarify the possibility of right coronary artery system anastomosis to left coronary system.MethodsA patient-specific 3D model was first reconstructed based on coronary computed tomography angiography (CCTA) images. Two different grafts, the normal multi-graft (Model 1) and the novel multi-graft (Model 2), were then implemented on this patient-specific model using virtual surgery techniques. In Model 1, the single graft was anastomosed to right coronary artery (RCA) and the sequential graft was adopted to anastomose left anterior descending (LAD) and left circumflex artery (LCX). While in Model 2, the single graft was anastomosed to LAD and the sequential graft was adopted to anastomose RCA and LCX. A zero-dimensional/three-dimensional (0D/3D) coupling method was used to realize the multi-scale simulation of both the pre-operative and two post-operative models.ResultsFlow rates in the coronary artery and grafts were obtained. The hemodynamic parameters were also showed, including wall shear stress (WSS) and oscillatory shear index (OSI). The area of low WSS and OSI in Model 1 was much less than that in Model 2.ConclusionsModel 1 shows optimistic hemodynamic modifications which may enhance the long-term patency of grafts. The anterior segments of sequential graft have better long-term patency than the posterior segments. With rational spatial position of the heart vessels, the last anastomosis of sequential graft should be connected to the main branch.

A predictive patient-specific computational model of coronary artery bypass grafts for potential use by cardiac surgeons to guide selection of graft configurations

“…Previous research studies have employed a variety of computational models to investigate coronary artery bypass grafting strategies. These have varied in complexity from simpler 0D lumped parameter models ( 92 , 93 ) to more sophisticated multi-scale 3D-0D models ( 81 , 94 ). A significant limitation of models employing only a lumped parameter approach is the oversimplification in representing wave propagation along the larger vessels ( 84 ); however, their advantage over 3D models is their relative computational efficiency and ease of implementation.…”

A vessel length-based method to compute coronary fractional flow reserve from optical coherence tomography images

“…OCT as an imaging modality can accurately generate lumen geometry of coronary arteries, and so has a strong potential for use in coronary hemodynamics simulation. Although there have been several computational methods of coronary arterial hemodynamics for patient-specific model reconstructed from CT images [ 2 – 4 , 32 – 34 ], their methods were not extended to OCT–FFR simulation. Recently, Wang et al [ 32 ] proposed a patient-specific model of coronary hemodynamics by coupling CFD with LPM.…”

“…Although there have been several computational methods of coronary arterial hemodynamics for patient-specific model reconstructed from CT images [ 2 – 4 , 32 – 34 ], their methods were not extended to OCT–FFR simulation. Recently, Wang et al [ 32 ] proposed a patient-specific model of coronary hemodynamics by coupling CFD with LPM. This method was applied to coronary hemodynamic simulations having bypass graft between coronary arteries [ 33 , 34 ].…”

Patient-Specific Hemodynamics of New Coronary Artery Bypass Configurations

“…As investigated in here, the stenosis sites of the left anterior descending artery ( LAD ) is particularly critical for surgical planning as almost half of the left ventricle flow is supplied through this branch [12].…”