[The effect of low dose aspirin on the platelet function in patients with acute myocardial infarction]

To assess the appropriate dose of aspirin in the treatment of patients with acute myocardial infarction (AMI), 60 cases of AMI were randomized into 2 groups, 30 cases each; one with conventional therapy, another with conventional therapy combined with daily oral aspirin 100mg. The second group was further divided into subgroup I with serum peak CK < 1000 U/L and subgroup II with serum peak CK > 1000U/L. The parameters of platelet function including plasma TXB2, TXB2/6-keto-PGF1 alpha, platelet aggregation induced by 5-HT and epinephrine were studied on different days for 3 weeks. The results revealed that there was a successful inhibition of platelet function as assessed by significant decrease of plasma TXB2 and TXB2/6-keto-PGF1 alpha ratio and inhibition of platelet aggregation in the subgroup I, but little effect on subgroup II. It is shown that in the treatment of AMI, a daily dose of 100mg of aspirin is insufficient for severe cases, and according to the observation in ISIS-2 study, a daily dose of aspirin around 160mg may be appropriate.