291 ISSN 1479-6678 Future Cardiol. (2014) 10(2), 291–300 REVIEW Aspirin for acute coronary syndrome prior to the percutaneous coronary intervention era The quest for the most favorable aspirin dose in acute coronary syndromes (ACS) has perplexed investigators and clinicians for many years. This discussion dates back to the early 1980s after the first positive randomized studies in patients with ACS were published. These small studies showed that aspirin, at doses from 75 mg/day up to 1300 mg/day, significantly reduced the incidence of cardiovascular (CV) death and myocardial infarction (MI) compared with placebo [1–5] . The first official guideline recommendation for aspirin use in the ACS patient population resulted from the ISIS-2 study, which was the first to demonstrate a significant reduction in mor- tality with aspirin following MI [6] . This was a prospective, placebo-controlled, randomized trial of 17,187 post-MI patients that demonstrated aspirin, at a dose of 162 mg/day, resulted in a 23% reduction in the odds of death within 5 weeks and a 42% reduction when combined with streptoki- nase when compared with placebo. Major bleeding with aspirin was not significantly different from the placebo group. The ISIS-2 trial studied aspirin with or without thrombolytic therapy. It did part of 10.2217/FCA.14.7 © 2014 Future Medicine Ltd REVIEW Optimal aspirin dose in acute coronary syndromes: an emerging consensus James J DiNicolantonio* ,1 , Nicholas B Norgard 2 , Pascal Meier 3,4 , Carl J Lavie 5,6 , James H O’Keefe 1,7 , Asfandyar K Niazi 8 , Saurav Chatterjee 9 , Kathleen A Packard 10 , Fabrizio D’Ascenzo 11 , Enrico Cerrato 11 , Giuseppe Biondi-Zoccai 12 , Sripal Bangalore 13 , Flavio D Fuchs 14 & Victor L Serebruany 15 1 Saint Luke’s Mid America Heart Institute, Kansas City, MO, USA 2 University of Buffalo, School of Pharmacy & Pharmaceutical Sciences, Buffalo, NY, USA 3 The Heart Hospital, University College London Hospitals, London, UK 4 Yale Medical School, New Haven, CT, USA 5 John Ochsner Heart & Vascular Institute, Ochsner Clinical School, The University of Queensland School of Medicine, New Orleans, LA, USA 6 The Department of Preventive Medicine, Pennington Biomedical Research Center, Baton Rouge, LA, USA 7 University of Missouri, Kansas City, Kansas City, MO, USA 8 Shifa College of Medicine, Islamabad, Pakistan 9 St Luke’s Roosevelt Hospital Center, Division of Cardiology, New York, NY, USA 10 Creighton University, School of Pharmacy & Health Professions, Omaha, NE, USA 11 University of Turin, Division of Cardiology, Citta Della Salute e Della Scienza, Torino, Italy 12 Sapienza University of Rome, Department of Medico-Surgical Sciences & Biotechnologies, Latina, Italy 13 New York University School of Medicine, New York City, NY, USA 14 Hospital de Clinicas de Porto Alegre, Universidade Federal do Rio Grande do Sul, Porto Alegre, Division of Cardiology & Postgraduate Studies Program in Cardiology, Rio Grande do Sul, Brazil 15 HeartDrug ™ Research Laboratories, Johns Hopkins University, Towson, MD, USA *Author for correspondence: Tel.: +1 607 738 8853; jjdinicol@gmail.com ABSTRACT: Numerous clinical trials testing the eicacy of aspirin for the secondary prevention of cardiovascular disease have been published. We reviewed the literature pertaining to aspirin dose in acute coronary syndrome patients. Clinical trials assessing the comparative eicacy of diferent doses of aspirin are scarce. This complex antiplatelet therapy landscape makes it diicult to identify the best aspirin dose for optimizing eicacy and minimizing risk of adverse events, while complying with the various guidelines and recommendations. Despite this fact, current evidence suggests that aspirin doses of 75–100 mg/day may ofer the optimal beneit:risk ratio in acute coronary syndrome patients. KEYWORDS • acute coronary syndrome • aspirin • bleeding • clopidogrel For reprint orders, please contact: reprints@futuremedicine.com