Research On Hemodynamics Of Abnormal Origin Of Right Coronary Artery

The right and left coronary arteries normally originate from the left and right coronary sinuses,but some people may have abnormal origin of coronary artery.Congenital coronary artery abnormality is the general term for a group of congenital coronary artery diseases.The Anomalous origin of the Right Coronary Artery(RCA)from the Left Coronary artery sinus(AORL)is one of the abnormal origins of the coronary arteries.Congenital coronary artery abnormalities are rare in clinical practice.The vast majority of patients are asymptomatic,but there are still a few patients with clinical symptoms such as myocardial ischemia,myocardial infarction and even sudden death.In recent years,researchers mostly studied AORL through human anatomy and clinical cases,and found that AORL had acute take-off Angle,slit-like orifice and other anatomical features.At present,the abnormal origin of coronary artery is mainly morphological examination,which has obvious deficiency in the evaluation of abnormal distal hemodynamic changes.It is not reliable to judge whether there is myocardial ischemia only by the degree of stenosis,so the study of its blood flow characteristics based on computational fluid dynamics(CFD)is particularly important for the clinical risk assessment and prognosis assessment of the origin of coronary artery abnormalities.This paper mainly compares the numerical simulation results to understand the changes in blood flow characteristics of AORL distortion.Based on medical imaging data,three dimensional reconstruction was performed in a normal and an AORL’s case.The steady-state hemodynamic analysis was carried out.The transient two-way fluid-structure coupling is used to make the numerical simulation conditions conform to the real environment of human body.In order to eliminate individual differences,16 normal models and 26 AORL models were simulated,and the data were collected for statistical analysis.The blood was assumed to be incompressible Newtonian fluid,and the vessel was assumed to be an isotropic,linear elastic material.The models are printed by 3D printing technology.Preliminary in vitro fluid experiment was designed and carried out to verify the correctness of the numerical simulation conclusion.The results of numerical simulation showed that the flow and wall pressure of right coronary artery in AORL decreased,and there is little difference in WSS.In the transient simulation,it was found that the change of AORL’s blood flow characteristics is the same as that of the steady-state simulation,while the deformation of the vessel wall increases.Through a large number of model numerical statistics,it was found that the cross-sectional area of the right coronary artery in the abnormal group is significantly smaller.In the systolic period,the wall pressure in the abnormal group was significantly reduced,and WSS was increased.The acute take-off angle was small in patients with clinical symptoms.In the symptomatic group,pressure was negatively correlated with an acute take-off angle.Finally,in vitro fluid experiments showed that AORL had a small blood flow into the right coronary artery.Fluid simulation and physical experiments show that AORL does affect the blood flow characteristics of human body,and may cause dizziness,myocardial ischemia,even sudden death and other symptoms.The results of this analysis are in accordance with the existing clinical medical research results.The study of hemodynamics provides a quantitative theoretical basis for clinical diagnosis.