Cardiovascular Study of Lisdexamfetamine in Healthy and Hypertensive Attention Deficit Hyperactivity Disorder Adults

The purpose of this research study is to learn about the effects of a medication called Vyvanse on the heart (cardiovascular system). The U.S. Food and Drug Administration (FDA) has approved Vyvanse for the treatment of Attention Deficit Hyperactivity Disorder (ADHD). People who have ADHD have trouble paying attention, organizing, and planning; these symptoms can cause problems at work, socially and at home. Vyvanse (also known as Lisdexamfetamine) is a stimulant class medication. There have been reports of serious cardiovascular effects in children and adults treated with stimulants. While there is no definite evidence that these events were related to the use of stimulants, the deaths have raised questions about the cardiovascular safety of stimulants. The study will involve in-depth cardiovascular tests, namely echocardiograph (ultrasound of the heart) and cardiopulmonary exercise test (also called stress test; subjects exercise on a bicycle while measuring their heart activity and breathing is monitored by cardiologists). The investigators predict to see changes in blood pressure and heart rate as shown in previous clinical studies, and that the in-depth cardiovascular tests will provide new insights into the cardiovascular impact of stimulants.