Coronary atherosclerotic heart disease is a type of heart disease in which atherosclerosis causes stenosis or occlusion of the lumen of the coronary arteries, leading to myocardial ischemia, hypoxia and even necrosis. In China, the proportion of deaths due to coronary atherosclerotic heart disease in the total number of deaths increased significantly, from 8.6% in 1990 to 15.2% in 2013. It is estimated that the total number of coronary heart disease deaths in China in 2013 was 1.394 million, which was 90% higher than that in 1990. At present, coronary atherosclerotic heart disease has become the first cause of death in six provinces, autonomous regions and municipalities in China[1]. The etiology of coronary atherosclerotic heart disease is complex, and the common risk factors include hypertension, diabetes, hyperlipidemia, smoking, obesity, etc. Meanwhile, abnormal coagulation and fibrinolysis play an important role in the occurrence and development of the disease. Unstable atherosclerotic plaque rupture is the initiating factor for the occurrence of acute myocardial infarction, which further causes platelet aggregation and fibrinogen activation, accelerates thrombosis, and leads to stenosis and occlusion of vascular lumen and acute myocardial ischemia. Therefore, to understand the coagulation and platelet functions of patients with acute myocardial infarction has an important role and significance for the diagnosis of the disease. Thromboelastic graph(TEG) is a new technique for evaluating blood clotting function in recent years, which can dynamically record the interaction among blood components such as coagulation factors, platelets and fibrinogen, as well as the whole process from blood clot formation to fibrinolysis. Thromboelastic graph(TEG) has nearly 20 standardized parameters, and more mature parameters in clinical application include: R time (min) : the time required for coagulation factor to fully activate fibrin formation, reflecting the activity of coagulation factor; K time (min), Angle(°) : the rate at which the blood clot strength reaches a certain level, which is mainly used to reflect the functional activity of fibrinogen; MA values(mm) : maximum blood clot strength and stability after formation, mainly used to reflect the function of platelets; LY30(%): the percentage of attenuation of blood clot amplitude within 30min after the occurrence of maximum amplitude of MA values, which is mainly used to evaluate fibrinolysis function. When LY30(%) exceeds 8%, hyperfibrinolysis is indicated. The above indicators have been widely used in different clinical fields, such as perioperative coagulation function monitoring, anticoagulant and antiplatelet drugs efficacy monitoring and blood transfusion guidance. However, it is rarely used to evaluate the condition of patients with acute myocardial infarction(AMI). Based on the pathological mechanism of AMI, the author used thromboelastic graph(TEG) related indicators to evaluate the severity of coronary artery lesions in patients with AMI, so as to provide effective guidance and reference for clinical diagnosis and treatment.
In this study, R time(min), K time(min) and LY30(%) in the STEMI group were lower than those in the NSTEMI group. The Angle(°) and MA values(mm) in the STEMI group were higher than those in the NSTEMI group, and there were significant differences in the thromboelastic graph(TEG) related indicators between the two groups. These results indicated that patients with STEMI had higher clotting activity and higher fibrin and platelet thrombus loads than those with NSTEMI.《Guidelines for the Diagnosis and Treatment of acute ST-segment Elevation Myocardial Infarction (2019)》[2] clearly indicate that the treatment principle for STEMI patients is to restore myocardial perfusion as soon as possible, and antithrombotic therapy (including antiplatelet and anticoagulant therapy) is necessary. Aspirin combined with one of the P2Y12 receptor inhibitors, dual antiplatelet therapy (DAPT) is the basis of antithrombotic therapy. For coronary angiography showed that thrombus burden in patients with severe, can be used by intravenous GPⅡb/Ⅲa receptor antagonist Tirofiban, help reduce slow flow or no reflow, improve myocardial microcirculation perfusion. In addition, anticoagulants such as heparin, enoxaparin, or pivastatin should be administered intraoperatively to STEMI patients undergoing percutaneous coronary intervention(PCI). Therefore,thromboelastic graph(TEG) can effectively reflect the condition of patients with acute myocardial infarction (AMI), and provide reference for individual medication.
At present, there are three main methods for scoring coronary angiography: Leaman scoring, Gensini scoring and SYNTAX scoring. Compared with Leaman score, Gensini score was more accurate in evaluating the possibility of cardiovascular and cerebrovascular adverse events in patients with acute coronary syndrome [8]. SYNTAX score seldom used in evaluation of patients with acute myocardial infarction(AMI), and for patients with stable coronary heart disease, it can assist to guide patients with multivessel lesions or left main disease to choose reasonable way of reascularization, and the higher the SYNTAX score, will predict who suffer coronary artery intervention(PCI) worse after the short-term clinical results of [9]. Therefore, Gensini scoring system was used to score coronary angiography in this study. The study showed that the Angle(°) and MA values(mm) gradually increased while the R time (min), K time (min) and LY30(%) gradually decreased with multi-vessel lesion or high Gensini score. Correlation analysis showed that R time (min), K time (min) and LY30(%) were negatively correlated with Gensini score, while Angle(°) and MA values(mm) were positively correlated with Gensini score.It further indicates that thromboelastic graph(TEG) related indicators is closely related to the severity of patients with acute myocardial infarction(AMI). The more severe the coagulation and fibrinolytic dysfunction, the more the number of coronary lesions and the more severe the stenosis. Therefore, thromboelastic graph(TEG) can be used as an effective indicator for predicting the condition of patients with acute myocardial infarction(AMI), evaluating coronary artery lesions, and guiding clinical treatment.