The Relationship Between Plasma Levels Of Homocysteine And Vascular Endothelial Function, VEGF In Patients With Acute Coronary Syndrome

Objective: The acute coronary syndrome (ACS) is a kind of main fatal disease that influence mankind health. It includes acute myocardial infarction (AMI) and unstable angina pectoris (UAP) its common pathologic physiology foundation is coronary artery atherosclerotic plaque rupture, thrombogenesis and/or vasospasm. Homocysteine (Hcy) is a new risk factor of coronary heart disease (CHD). Hcy can promote the occurrence and development of artherosclerosis (AS) in multiple mechanisms. Endothelial cells impairment and dysfunction are important beginning links of AS occurrence, endothelial cells secrete and release vasoactive substance to be out of balance,cause to coronarospasm and atherosclerotic plaque rupture, platelet aggregate and thrombogenesis, meanwhile endothelial cells antithrombotic capability degrade, the hematological coagulability increase, thrombogenesis is promoted, promote the occurrence and development of ACS. The aim of this study is to alter plasma level of homocysteine by folic acid and VitaminB₁₂ and investigate the relationship between Hcy and vascular endothelial growth factor( VEGF) , nitric oxide(NO)and endothelial dependent dilatation(EDD), explore the possible pathogenesis mechanisms of homocystein to cause endothelial impairment and dysfunction in ACS and to provide clinical evidence for treatment . Methods: The study group comprised 96 consecutive patients with ACS in cardiac center of People's Hospital of Hebei Province from Oct. 2003 to Oct. 2004, including 61 patients with unstable angina pectoris, 35 patients with acute myocardial infarction. The diagnostic criteria of ACS refer 1994 AHCPR reference. The subjects were divided in two groups randomly, 49 patients in treatment group, and 47 patients in control group. The patients in treatment group take orally folic acid 5mg/d,and VitB₁₂ 250μg /d. The other conventional medications for CHD are the same in all patients. Exclusion criteria: left ventricular ejection fraction<30%, valvular heart disease, AMI for thrombolysis ,hyperthyroidism, recent operation and injury, renal or liver dysfunction, acute or chronic inflammation, acute leukemia, acute cerebrovasular disease, bronchial asthma, von Willebrand disease, cancer, oral vitamins, lack of estrogen, organ transplantation, self immunity disease 。Age, sex, hypertension, diabetes, TG, TC, HDL-C, LDL-C, VLDL-C, smoking and CHD family history in every subjects,underwent PCI,were recorded in detail. Blood sampling: Peripheral blood samples were taken onthe second day after determination, 4 weeks, 8 weeks and 12weeks respectively. Coded samples were stored at -80℃and analyzed in a single batch for the study, thus, patient management was independent of these results. Levels of Hcy , VEGF were measured with ELISA,and NO were measured with nitrite reductase method. LOGIQα400 diasonography was used to measure the endothelial dependent dilation of brachial artery with Celermajer's method,ultrasound probe frequency 7.0MHz,result were recorded in detail. Statistics analysis: SPSS11.0 software pack was used to make statistical-analysis. Initially the homogeneity of variance between all the groups was analyzed. All the numerical data was shown as mean±standard deviation and students t test was used to establish significance. Linear Correlation analysis was used to measure the coefficient of correlation about the correlation data.We took p<0.05 as statistic significant level. Results: 1 There was no statistical difference between two groups about clinical feature. (attached table 1); The proportion of hyperhomocysteinemia is 48.95% in all subjects, 51.43% in AMI, and 47.54% in UAP. 2 The comparisons parameter in two groups. 2.1 The levels of Hcy ,NO ,VEGF and EDD were no significantly difference between treatment group and control group. Hcy (19.14±8.97μmol/l vs 18.85±10.07 μmol/l ,p=0.883);NO(84.02±16.48μmol/l vs 84.78±14.98μmol/l,p=0.815 ) ; VEGF ( 209.07±87.06pg/ml vs 201.11±92.94pg/ml , p=0.666 ); EDD ( 7.81±2.95 %vs8.15±2.83% p=0.581);( attached table 2,3,4, 5) 2.2 The...