Effects Of Anti-platelet Drug Clopidogrel On The Pletelet Function And Fibrinolytic System In Patients With Acute Coronary Syndrom Undergoing Therapy

BACKGROUND: Acute coronary syndrome (ACS), which includes unstable angina, ST-segment elevation myocardia infarction (STEMI), non-ST-segment elevation myocardia infarction (NSTEMI), is a special group of coronary heart diseases (CHD) .It is caused mainly by thrombosis based on coronary atherosclerosis rupture. It has been testified that platelet and fibrinolytic system play an improtant role in the pathogenesis of ACS.The anti-platelet medicine and thrombolysitic treatments have been proved to have definite theraputic effect on ACS. Now,according to the data of pharmacodynamics and pharmacokinetics,the availability of a new antiplatelet agent clopidogrel, with a proven efficacy in the prevention of cardiovascular events , suggests the opportunity of reviewing the mechanisms of instability and the therapeutic strategies in patients with ACS. It onsets more quickly and is more powerful but with fewer side effects.So it is recommended in the cure strategy of ACS, especially for the patients undergoing PCI.In this preasent study, we aim to 〆xamine the-3-effect of a loading dose clopidogrel on the platelet function and fibrinolytic system of patients with ACS , ヽompare the effectiveness of different dosage and administration ways on the platelet function and fibrinolytic system of patients with ACS, and also to exemine the recent -effect of antiplatelet drugs on patients with ACS undergoing PCI. METHOD: From June 2002 to March 2003, 135 patients with ACS are enrolled in this study.All patients are given aspirin 300mg ?d-1 and are divided into 5 groups depending on the dosage and administration way as followed: ㎜oading dosage group (n=30): patients received clopidogrel 300mg bolus and were phlebotomized 2 hours later.㏑outine dosage group(n=30): patients received clopidogrel 75mg ?d1-1 continuously and were phlebotomized 3 days later?Ticlopidine group (n=25) : patients received ticlopidine 250mg ?d-1 continuously and were phlebotomized 3 days later ?blank control group (n=25): patients received the basic drug of aspirin only as the way described initially,and were phlebotomize 2 hours and 3 days later respectively?AMI combination group(n=25): patients received clopidogrel 300mg bolus plus low-molecular-weight heparin 40mg and were phlebotomize 2 hours later﹉ealth control group(n=20): no medicine are administrated.Plasma GMP-140, TXB2, PagF, t-PA activity, PAI activity and D-dimer antigen were measured at pre-treatment and post-treatment.RESULT: ㊣n ACS at pre-treatment, the level of plasma GMP-140, TXBa, PagF, PAI activity and D-dimer are higher than that of health control group, but t-PA activity lower (P<0.01) , and the changes of these markers are more significantly in AMI patients than UAP patients(P<0.05 );〢fter the therapy, in loading dosage group and routine dosage group, Plasma GMP-140, PagF, PAI activity are lower than that of blank control group (P<0.05 );in loading dosage group,routine dosage group and ticlopidine group plasma GMP-140, PagF, PAI activity are lower than pre-treatment (P<0.05) ;in routine dosage group and ticlopidine group ,-4-D-dimer is lower and t-PA activity is highter than pre-treatment (P<0.05) ; ?There is no significant difference of these markers of platelet founction and PAI activity among loading dosage group,routine dosage group and ticlopidine group (P>0.05);?After the therapy, in AMI combination group, Plasma GMP-140, PagF, PAI activity are lower than pre-treatment(P<0.05) .CONCLUSION: ?ACS patients have platelet activation and fibrinolytic system function repression, and it is more serious in AMI patients than UAP patients ? Loading dosage clopidogrel can inhibite the platelet activation effectively 2h later after drug administration?Loading dosage clopidogrel can achieve the effect of continuous adminstration of clopidogrel 75mg ?d-1 3 days and Ticlopidine 250 mg ?d-1 3 days 2 hours later after drug administration. ?The long-time use of routine dosage colpidogrel may improve the activity of fibrin...