The American Heart Association/American College of Cardiology in 2014 published a focused update of the 2007 and 2012 guidelines for non–ST-segment elevation acute coronary syndrome (NSTE-ACS). The management of ST-segment elevation myocardial infarction (STEMI) is described in a separate guideline published in 2013. The focused updates to the guidelines contain updated recommendations for dual antiplatelet therapy, including use of the P2Y12 inhibitor ticagrelor, which was recently approved by the Food and Drug Administration. Nurses caring for patients with acute coronary syndrome must have a good understanding of the current treatment guidelines for such patients, to help ensure delivery of evidence-based care. This review article uses a case study–based approach to describe how the new guidelines affect clinical decision making when choosing appropriate antiplatelet therapy for patients with NSTE-ACS or STEMI, depending on the patient’s clinical history and presenting characteristics.