Antiplatelet Therapy Resistance in Patients With Acute Coronary Syndrome With St-Segment Elevation

Aim. To evaluate the incidence of acetylsalicylic acid (ASA) and clopidogrel resistance in patients with acute coronary syndrome with ST-segment elevation and to find out possible clinical factors, contributing to this state. Material and methods. 58 patients with acute coronary syndrome with ST-segment elevation (49 men, 9 women) were included into the study. Age of patients ranged from 37 tо 84 y.o. (60,8±12,3 y.o. in average). Platelet aggregation was assessed by the Born’s method. Level of arachidonic acidinduced aggregation ≥20% considered as ASA resistance. Decreasing of ADP-induced platelet aggregation ≥20% considered as ASA resistance. Decreasing of ADP-induced platelet aggregation <10%, 10-29%, and ≥30% compared to the basal level considered as clopidogrel resistance, “partial clopidogrel resistance” or clopidogrel sensitiveness, respectively. Results . ASA and clopidogrel decreased arachidonic acid-induced and ADP-induced aggregation after 7 days of the therapy compared to the basal levels (р<0,05). The highest incidence of resistance was registered in patients with diabetes mellitus (71,1% to ASA, 57,1% to clopidogrel) and obe-sity (42,9% to clopidogrel). Conclusion. The incidence of ASA and clopidogrel resistance reached to 28,9% and 24,4% respectively in patients with acute coronary syndrome with ST-segment elevation. The prevalence of antiplatelet therapy resistance is significantly higher in patients with diabetes mellitus and obesity (р<0,05). The incidence of early complications of acute myocardial infarction is higher in patients resistant to ASA and clopidogrel.