Correlation of Endothelial Function and Early Coronary Artery Disease in Humans

Endothelin in the Coronary Circulation in Early Atherosclerosis in Humans

Qualifying patients who are scheduled for angiogram with endothelial function testing are approached to participate in this protocol (consent form reviewed with patient). Those who are willing to participate will have additional measurements taken during their angiogram as part of this protocol. Patients who are diagnosed with Endothelial Dysfunction as a result of a clinically indicated angiogram will be eligible to participate in a 6 month medication trial (Atrasentan vs. placebo - randomized, blinded trial). Patients are monitored closely during the 6 month trial via phone calls and blood testing for assessment. At the end of the 6 months they return to Mayo for a repeat angiogram to assess endothelial function for any changes or improvements.

Aim I: To determine the activity of the endogenous endothelin system in the coronary circulation in humans with coronary endothelial dysfunction and atherosclerosis risk factors. Aim II: To assess the potential of chronic endothelin receptor antagonists to improve preexisting coronary endothelial dysfunction and myocardial perfusion in humans and Aim III: To assess the effect of chronic endothelin receptor antagonism on the endogenous nitric oxide system in association with oxidative stress in humans with early coronary disease risk factors.

Inclusion Criteria:

• Age > 18 years and < 85 years
• Male or female

Exclusion criteria:

• Left dominant circulation
• Heart failure with EF <40%
• Unstable angina
• MI or angioplasty of the LAD or circumflex with 6 months prior to entry into the study
• Use of radiographic contrast agent within 12 hours of entry into the study
• Use of investigational agents within one month of entry into the study
• Patients who require treatment with positive inotropic agents other than digoxin during the study
• Patients with cerebrovascular accident within 6 months prior to entry into the study
• Significant endocrine, hepatic, renal disorders; local or systemic infectious disease within 4 weeks prior to entry into study
• Pregnancy or lactation
• Mental instability
• Federal Medical Center patients