Compared with aspirin , thienopyridines significantly reduced gastrointestinal adverse effects .
However , thienopyridines increased the odds of skin rash and diarrhoea , ticlopidine more than clopidogrel .
Allocation to ticlopidine , but not clopidogrel , significantly increased the odds of neutropenia .
The thienopyridine derivatives are at least as effective as aspirin in preventing serious vascular events in patients at high risk , and possibly somewhat more so .
However , the size of any additional benefit is uncertain and could be negligible .
Clopidogrel has a more favourable adverse effects profile than ticlopidine and so is the thienopyridine of choice .
BACKGROUND Aspirin is the most widely studied and prescribed antiplatelet agent for preventing serious vascular events , reducing the odds of such events among high vascular risk patients by about a quarter .
Thienopyridine derivatives inhibit platelet activation by a different mechanism and so may be more effective .
OBJECTIVES To determine the effectiveness and safety of thienopyridine derivatives ( ticlopidine and clopidogrel ) versus aspirin for preventing serious vascular events ( stroke , myocardial infa rct ion ( MI ) or vascular death ) in patients at high risk , and specifically in patients with a previous TIA or ischaemic stroke .
Comparison of antiplatelet effects of aspirin, ticlopidine, or their combination after stent implantation.
BACKGROUND This study was performed to analyze the influence of either aspirin , ticlopidine , or their combination on platelet activation and aggregation parameters after stent implantation . METHODS AND RESULTS Sixty-one patients with successful implantation of a single Palmaz-Schatz stent in a native coronary artery were r and omly assigned to either group A ( aspirin 300 mg/d+ticlopidine 2X250 mg/d ) , group B ( ticlopidine 2X250 mg/d ) , or group C ( aspirin 300 mg/d ) . Platelet activation was evaluated on days 1 , 7 , and 14 by flow cytometry measurement of expression of CD62p ( p-selectin ) and the binding of fibrinogen to the platelet surface glycoprotein IIb/IIIa receptor . Platelet aggregation was induced by addition of ADP or collagen . Differences between treatment groups were compared by ANOVA . Between days 1 and 14 , we observed a significant decrease in collagen-induced platelet aggregation in group A ( 62.2+/-2.5 % versus 36.9+/-3.1 % ) , whereas an increase was seen in group B ( 58.3+/-2.5 % versus 67.7+/-3.2 % ) and no change was seen in group C ( P<.0001 ) . The ADP-induced aggregation declined significantly in group A ( 74.7+/-1.4 % versus 55.3+/-2.6 % ) , whereas a delayed reduction was seen in group B ( 72.0+/-3.0 % versus 52.6+/-4.2 % ) and no change was seen in group C ( P=.0017 ) . The CD62p expression declined significantly in groups A ( 68.2+/-2.7 % versus 41.3+/-2.7 % ) and B ( 64.8+/-2.9 % versus 39.3+/-3.5 % ) but not in group C ( P<.0001 ) . Moreover , the fibrinogen binding decreased significantly in group A ( 61.0+/-4.3 % versus 36.3+/-4.2 % ) and with delay in group B ( 58.3+/-2.2 % versus 39.4+/-3.0 % ) , whereas no alterations were seen in group C ( P=.012 ) . CONCLUSIONS Our results demonstrate synergistic and accelerated platelet inhibitory effects of ticlopidine plus aspirin in patients after stent implantation compared with a monotherapy with either ticlopidine or aspirin alone
Compared with aspirin , thienopyridines significantly reduced gastrointestinal adverse effects .
However , thienopyridines increased the odds of skin rash and diarrhoea , ticlopidine more than clopidogrel .
Allocation to ticlopidine , but not clopidogrel , significantly increased the odds of neutropenia .
The thienopyridine derivatives are at least as effective as aspirin in preventing serious vascular events in patients at high risk , and possibly somewhat more so .
However , the size of any additional benefit is uncertain and could be negligible .
Clopidogrel has a more favourable adverse effects profile than ticlopidine and so is the thienopyridine of choice .
BACKGROUND Aspirin is the most widely studied and prescribed antiplatelet agent for preventing serious vascular events , reducing the odds of such events among high vascular risk patients by about a quarter .
Thienopyridine derivatives inhibit platelet activation by a different mechanism and so may be more effective .
OBJECTIVES To determine the effectiveness and safety of thienopyridine derivatives ( ticlopidine and clopidogrel ) versus aspirin for preventing serious vascular events ( stroke , myocardial infa rct ion ( MI ) or vascular death ) in patients at high risk , and specifically in patients with a previous TIA or ischaemic stroke .