Objective: To study platelet reactivity at different times while on dual antiplatelet
therapy (DAPT) with aspirin (ASA) and clopidogrel in patients treated with bioactive
stents (TITAN2
®) or everolimus-coated stents (XIENCE V®) and one month after
clopidogrel cessation.
Background: Coronary intervention damages the endothelium and causes platelet
response leading to thrombotic occlusion, which is prevented with DAPT.
Methods: We studied 20 patients with bioactive stent and stable ischemia (BAS-SI
group); 31 patients with bioactive stent and acute coronary syndrome (BAS-ACS
group) and 31 patients with stable ischemia and everolimus-coated stent (EVE group).
DAPT was administered (ASA 100 mg/day and clopidogrel 75 mg/day) for one year in
BAS-ACS and EVE groups and for 1 month in BAS-SI group. Platelet aggregation
induced by different agonists and platelet recruitment were analyzed at different times
of DAPT and 1 month after clopidogrel cessation.
Results: After one month of DAPT, platelet aggregation showed no difference between
groups; at 12 months of DAPT, the response to collagen and ADP increased in EVE
group. Platelet recruitment at 1 month was higher in the BAS-ACS than the other
groups; after 12 months, recruitment increased in the EVE group with respect to BASACS.
Platelet aggregation and recruitment in diabetics were significantly higher in all
situations than in non-diabetic patients. Clopidogrel withdrawal increased ADPinduced
aggregation and collagen-induced aggregation and recruitment.
Conclusion: Platelet reactivity in patients with DAPT varies with time, depending on
the subset of patients, the type of the stent implanted and the time after implantation.
Keywords: Platelet Activity, Stent, Recruitment, Aggregation, Dual Antiplatelet
Therapy, Clopidogrel Withdrawal.
