Patients presenting to the emergency department with chest discomfort who are being administered aspirin will be offered enrollment in this study. At the time of their zero and two hour troponin we will also draw platelet aggregration studies to determine the effects of aspirin upon platelets. Narcotic medicines slow the absorption of aspirin. Morphine has therefore been shown to decrease the effectiveness of aspirin. Many providers therefore use fentanyl instead, however little is known about the effects of fentanyl upon aspirin. We will therefore compare the platelet reactivity of patients receiving morphine, fentanyl, or no narcotics
