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 .
Prevention of thromboembolism with ticlopidine shortly after valve repair or replacement with a bioprosthesis.
BACKGROUND AND AIMS OF THE STUDY This study investigated the efficacy of postoperative ticlopidine as antiplatelet therapy in patients shortly after heart valve repair or replacement . METHODS Between 1990 and 1995 , 235 consecutive patients underwent either valve repair ( n = 67 ) or replacement with a bioprosthesis ( n = 168 ) . The bioprostheses used were Carpentier-Edwards porcine or pericardial ( n = 158 ) valves , Prima stentless valves ( n = 3 ) and cryopreserved homografts ( n = 7 ) . Types of repair were aortic ( one ) , mitral annuloplasty with Carpentier ring ( 65 ) and tricuspid repair ( one ) . Mean patient age was 67 ( range : 16 to 83 ) years for valve replacement and 57 ( range : 32 to 74 ) years for repair ( p < 0.01 ) .  Atrial fibrillation  occurred in 34 % of patients . The hospital mortality rate was 11 % ( 26 patients ) . Of the 209 survivors , 137 were assigned to antiplatelet treatment with ticlopidine for the first three months of follow up . The other 72 received either oral anticoagulation ( coumadin ; n = 40 ) , aspirin ( n = 14 ) or no medication ( n = 18 ) . In 15 patients , ticlopidine treatment was interrupted due to diarrhea ( 13 cases ) , mild allergic reaction ( one ) or anemia ( one ) . The mean follow up was 3.2 years ( range : 1 month to 6 years ) ; cumulative follow up was 684 patient-years ( pt-yr ) and was complete in 96 % of cases . RESULTS There were two episodes of thromboembolism in the ticlopidine group at 1 month and 6 months respectively , with a linearized incidence of 0.5 % pt-yr . In the coumadin group there were four episodes of thromboembolism , three within the first three months of follow up . The linearized incidence was 3 % pt-yr ( p < 0.01 ) . There were three episodes of hemorrhage in the ticlopidine group in the first three months of follow up and one in the coumadin group . The linearized incidence was 0.75 % pt-yr . CONCLUSIONS Following heart valve repair or replacement with a bioprosthesis , the first three months is a high-risk period for thromboembolism . Ticlopidine seems to prevent this complication better than conventional therapy with oral anticoagulants . Nevertheless , hemorrhage continues to be a problem with ticlopidine therapy
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 .