Regadenoson R-T Perfusion Imaging Trial

Inclusion Criteria:

• Male or female. Age ≥30 years.
• Resting Left Ventricular Ejection Fraction > 40% using Simpson's biplane measurement.
• Scheduled for coronary angiography within 30 days of the Regadenoson stress test.
• Negative urine pregnancy test within 2 hours of ultrasound contrast administration required of females of childbearing age unless post-menopausal or with evidence of surgical sterilization.
• Be conscious and coherent, and able to communicate effectively with trial personnel.
• Agreeable to undergo the additional stress test and coronary angiography
• Have at least an intermediate likelihood of coronary disease based on the following clinical profile
• Good apical echo images with at least 50% of each coronary artery territory well visualized.

Exclusion Criteria:

• Known or suspected hypersensitivity to ultrasound contrast agent used for the study.
• Pregnancy or lactation.
• Complicated hemodynamic instability (i.e., NYHA Class IV heart failure, unstable angina at rest despite medical therapy).
• Life expectancy of less than two months or terminally ill.
• Congestive (idiopathic) or hypertrophic cardiomyopathy.
• Known left main disease.
• Heart transplant recipient, hypertrophic cardiomyopathy, acute myo- or pericarditis.
• Resting Left Ventricular Ejection Fraction < 40%
• Large inducible perfusion defects or wall motion abnormalities during prior stress imaging study associated with left ventricular cavity dilatation.
• Early positive treadmill EKG within the first stage of the test.
• History of >1st degree heart block, sick sinus syndrome or high grade AV block without a pacemaker.
• Dipyridamole use within 30 hours of stress test, or consumption of methylxanthines within 12 hours, or use of sublingual nitroglycerin within two hours.
• Participation In another investigational study within one month of this study.