Distribution of Rubidium-82, Nitrogen-13 Ammonia, and Florine-18 Fluorodeoxyglucose in Normal Volunteers

Establish the normal distributions of Rb-82, N-13 ammonia, and F-18 FDG in the heart using PET imaging for subsequent use in the evaluation of U of M clinical patient studies using these procedures. Normal healthy volunteers will be extensively screened for this study. Subjects will be given IV administration of Rb-82 and N-13 to acquire rest/stress imaging. Patients not excluded by any abnormality during the Rb-82 and N-13 rest/stress studies will be given 100 grams of dextrose orally and when glucose levels are below 120mg/dl, the F-18 FDG imaging will be administered IV per protocol.

Cardiac rubidium-82(Rb-82)and N-13 ammonia heart perfusion (blood flow) studies and florine-18 fluorodeoxyglucose (F-18FDG)heart PET glucose metabolism studies are important tools for the evaluation of patients with coronary heart disease. This includes patients with known or suspected heart disease and patients with congestive heart failure following myocardial infarction (heart attack)with indeterminant assessments of cardiac health from other imaging modalities, for example SPECT perfusion imaging and echocardiography. These studies help physicians plan potentially life saving procedures to re-establish coronary blood flow to living but severly compromised heart muscle. Rb-82 and N-13 ammonia studies can tell if there is reduced blood flow to the heart muscle either at rest or during stress. FDG studies can tell whether there is any chance of a beneficial effect from coronary revascularization procedures, for example coronary angioplasties and stents or coronary artery bypass. Revascularization procedures in patients like these may be technically difficult, risky and costly. Unfortunately the normal cardiac distributions of Rb-82, N-13 and ammonia, and F-18FDG for computer analysis of human studies are not well known and what is known is not widely available for clinical use. The latest imaging guidelines from the American Society of Nuclear Cardiology recommend that Rb-82, N-13 ammonia, and FDG cardiac studies be compared to normal distributions or patterns of these radiotracers in the heart developed from a series of normal individuals. The purpose for these studies is to generate databases of normal Rb-82, N-13 ammonia, and F-18FDG cardiac distributions so that they can be used in the analysis of clinical patient studies at the University of Michigan Hospital.

• Procedure: Rb-82 and N-13 ammonia imaging
  Intravenous administration of Rb-82 and N-13. Images will be acquired according to standard clinical imaging protocol and reviewed. Patient will be connected to an EKG machine to monitor the heart and blood pressure will be monitored as well. For Rb-82 images, 40 mCi(millicuries/a measurement of radioactivity) will be used. For N-13 ammonia images, 20 mCi (millicuries)will be used. Acquisition time for both rest and stress studies to be completed should take approximately 30 min.
• Procedure: F-18 FDG imaging
  Volunteers undergoing the F-18 FDG protocols will undergo: (1) glucose loading protocol for "viability protocol imaging" with the hyperinsulinemic euglycemic clamp according to standard procedures in our laboratory, and (2) "inflammation protocol imaging" using a high fat preparatory diet and three sub-therapeutic heparin doses (10 units / kg each) according to standard procedure in our laboratory. When metabolically prepared with the viability protocol and the inflammation protocol (two separate days), 10 mCi (millicuries) of F-18 FDG will be administered IV per FDG protocols, via heparin lock. 40-60 minutes following FDG injections PET imaging will be performed according to standard clinical imaging protocol.

• Rb-82 or N-13 images acquired
  Rest and vasodilator stress Rb-82 images or N-13 ammonia images will be acquired according to standard clinical imaging protocol and reviewed. Each of these two studies require the injection of Rb-82 by intravenous administration (IV)which will be started in the patient's arm.
  Intervention: Procedure: Rb-82 and N-13 ammonia imaging
• F-18 FDG Imaging
  Volunteers not excluded by abnormal rest/stress Rb-82 or N-13 ammonia imaging will begin F-18 FDG protocol.
  Intervention: Procedure: F-18 FDG imaging

Inclusion Criteria:

• Healthy normal volunteers

Exclusion Criteria:

1. Prior participation in a study with significant radiation exposure
2. Significant radiation exposure for other reasons, example: routine medical care
3. Medical history of physical or treadmill exercise stress EKG evidence of heart or vascular disease.
4. Cardiac A-V conduction abnormalities
5. Diabetes Mellitus
6. Liver Disease
7. Kidney Disease
8. Other chronic debilitating illnesses ( Example: Rheumatoid Arthritis, Emphysema, Parkinson's Disease).
9. Tobacco use, hypertension, diabetes, family history of coronary artery disease before age 45 in males and 55 in females or other coronary risks factors of more than mild severity
10. Claustrophobia (fear of tight spaces)
11. Pregnancy
12. Inability to lay flat with your arms positioned next to your head for approximately 20 minutes.
13. Morbid Obesity
14. Asthma
15. Breasts Implants
16. Use of anabolic steroids
17. Use of recreational drugs