Effects of different antithrombotic interventions on platelet activation in patients with atrial fibrillation

Objective To observe the effects of different antithrombotic interventions on the changes of plasma lysophosphatidic acid （LPA） level in patients with nonvalvular atrial fibrillation （NVAF） and to provide the basis for clinical antithrombotic therapy. Methads A total of 235 patients with NVAF who did not receive antithrombotic therapy diagnosed by clinical and auxiliary examinations were randomly allocated to receive aspirin （100mg/d） plus dipyridamole （100mg/d） （n = 76）, aspirin （100 rag/d） plus fixed-dose warfarin （1.25 mg/d） （n =79）, and dose-adjusted warfarin （international normalized ratio （INR） range of 1.5 to 2. 1） （n =80）. They were redivided into 〈60, 60-75, and ≥76 year-old groups according to their age. The plasma LPA levels were measured and compared before treatment and 2 and 6 weeks after treatment. Results The plasma LPA levels were decreased more significantly in the aspirin plus fixed-dose group than those in the aspirin plus dipyridamole and dose-adjusted warfarin groups （all P 〈 0.01 ）. Two and 6 weeks after treatment with aspirin plus dipyridamole in the 〈 60 year-old group, the plasma LPA levels were significantly lower than those before treatment （all P 〈0.01）. Two and6 weeks after treatment with aspirin plus fixed-dose warfarin in the 〈 60 year-old group, the plasma LPA levels were significantly lower than those before treatment （all P 〈 0.01 ）. Two and 6 weeks after treatment with aspirin plus fixed-dose warfarin in the 60-75 year-old group, the plasma LPA levels were significantly lower than those before treatment （all P 〈0.01）. Two and 6 weeks after the treatment with dose-adjusted warfarin （INR 1.5-2. 1 ） in patients in each age group, the plasma LPA levels were significantly lower than those before treatment. Conclusion The different antithrombotic therapeutic modalities have different effects on platelet activation in patients with NVAF in different age groups, The patients in the 〈 60 year-old group can receive aspirin plus dipyridamole, the patients in the 〈 75 year-old group can receive aspirin plus fix-dose warfarin, and the patients 〉 75 year-old, dose-adjusted warfarin （INR 1.5-2.1 ） should be recommend. Key words: atrial fibrillation;  platelet activation;  lysophosphatidic acid;  ischemic stroke