Inhibition of platelet aggregation by aspirin alone and by aspirinin combination with clopidogrel: synergy, incompatibility and additivity

摘要

The results of combined anti-platelet therapy for aspirin followedby aspirin plus ticlopidine were previously reported in terms ofinhibition of platelet aggregation in patients with history of ischemicstroke. Another anti-platelet agent, considered to be safer and said tohave the same platelet inhibitory effects, clopidogrel has now replacedticlopidine. We sought to study again the effects of combinationaspirin-clopidogrel therapy in a different group of patients withischemic stroke. We wanted to expand our experience with a fuzzy theorysolution to the search for synergy, incompatibility and additivity inindividual patients taking combination anti-platelet therapy. Weevaluated 56 patients receiving combination aspirin-clopidogrel therapyfor prevention of recurrent arterial (vascular) occlusion, i.e.,prevention of stroke, myocardial infarction and lower extremityischemia. Platelet aggregation studies were performed ex-vivo on blooddrawn from each patient while taking aspirin alone and later whiletaking aspirin plus clopidogrel. The methodology for performance ofplatelet aggregation studies has been published elsewhere and in no waydeviates from that original protocol