Background: Although platelet activation plays a major role in the pathogenesis of atherothrombotic events, there is no data whether platelet hyper-reactivity constitute a risk factor for cardiovascular (VCS) event in healthy population.
Methods: Platelet reactivity was determined in 89 consecutive healthy subjects [64 (72%) men, mean age 51±11 years]. Platelet aggregation was assessed by conventional aggregometry, and platelet adhesion under flow conditions by cone-and-plate(let) technology (Impact-R).Subjects were prospectively followed for a mean follow-up of 90±6 months (range: 79-102) for the occurrence of major CVS events including all-cause mortality, nonfatal myocardial infarction, stroke, coronary artery bypass grafting, and percutaneous coronary intervention.
Results: During the follow-up period 11 subjects sustained a CVS event. All subjects with- but only 68% without CVS events were males (p=0.02). Moreover, fasting glucose (102± 19 vs. 89±18 mg%, p=0.03) and homocystein levels ( 14± 4 vs. 11±3, p=0.04) were higher in those with compared to without CVS events, but otherwise there were no significant differences in. their age, other CV risk factors, left ventricular ejection fraction and lipoproteins. ADP (79+18 vs. 60±28, p=0.005) and arachidonic acid-induced platelet aggregation (75±31 vs. 51±32, p=0.017) were significantly higher in subjects with compared to those without CVS events. In addition, platelet adhesiveness as reflected by surface coverage of pro-thrombotic surface under flow conditions was greater in those with than without CV events (14±8% vs. 9±6%, p<0.05).
Conclusions: Enhanced intrinsic platelet reactivity, as measured by both platelet aggregation and adhesion under flow conditions, is associated with increased risk of CVS events, along with other classical risk-factors, in healthy subjects with otherwise no evidence ob CVS disease.
