Regadenoson Real Time Perfusion Imaging Trial-Optison

The purpose if this study is to examine how effective Regadenoson is in detecting coronary artery disease during a stress echocardiogram when Optison is administered. Optison is a contrast agent that improves the images of the heart on the echocardiogram (echo) machine. Optison is approved by the Food and Drug Administration (FDA) to use during stress echocardiograms. Regadenoson is a commercially available rapid acting stress agent that is used to chemically increase the heart rate and is approved for nuclear imaging tests. Regadenoson is a FDA approved drug but not for the intended use in this study.