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 .
Randomized Trial of Warfarin, Aspirin, and Clopidogrel in Patients With Chronic Heart Failure: The Warfarin and Antiplatelet Therapy in Chronic Heart Failure (WATCH) Trial
Background — Chronic heart failure remains a major cause of mortality and morbidity . The role of antithrombotic therapy in patients with chronic heart failure has long been debated . The objective of this study was to determine the optimal antithrombotic agent for heart failure patients with reduced ejection fractions who are in sinus rhythm . Methods and Results — This prospect i ve , r and omized clinical trial of open-label warfarin ( target international normalized ratio of 2.5 to 3.0 ) and double-blind treatment with either aspirin ( 162 mg once daily ) or clopidogrel ( 75 mg once daily ) had a 30-month enrollment period and a minimum of 12 months of treatment . We enrolled 1587 men and women ≥18 years of age with symptomatic heart failure for at least 3 months who were in sinus rhythm and had left ventricular ejection fraction of ≤35 % . The primary outcome was the time to first occurrence of death , nonfatal myocardial infa rct ion , or nonfatal stroke . For the primary composite end point , the hazard ratios were as follows : for warfarin versus aspirin , 0.98 ( 95 % CI , 0.86 to 1.12 ; P=0.77 ) ; for clopidogrel versus aspirin , 1.08 ( 95 % CI , 0.83 to 1.40 ; P=0.57 ) ; and for warfarin versus clopidogrel , 0.89 ( 95 % CI , 0.68 to 1.16 ; P=0.39 ) . Warfarin was associated with fewer nonfatal strokes than aspirin or clopidogrel  . Hospitalization for worsening heart failure occurred in 116 ( 22.2 % ) , 97 ( 18.5 % ) , and 89 ( 16.5 % ) patients treated with aspirin , clopidogrel , and warfarin , respectively ( P=0.02 for warfarin versus aspirin ) . Conclusion — The primary outcome measure and the mortality data do not support the primary hypotheses that warfarin is superior to aspirin and that clopidogrel is superior to aspirin
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 .