Investigation of the Causes of Health Disparities in African Americans With Coronary Artery Disease on Clopidogrel

African Americans with coronary artery disease who have been prescribed clopidogrel (also known as Plavix), an antiplatelet drug will be enrolled. The purpose of this study is to help identify why African Americans are at an increased risk of having a major heart attack or stroke after a common procedure to open up blocked arteries with stents. The knowledge to be gained from this study includes: 1. A better understanding of the metabolism of the antiplatelet drug, clopidogrel, and abnormal platelet function in African Americans; this understanding may provide a basis for potential future therapy 2. A better understanding of challenges to taking clopidogrel as prescribed by a doctor and opinions about a genetic test related to this medicine.