Microvascular Flow Assessment Repeatability Study: The MARS Study

Microvascular Flow Assessment of the Periadventitial Adipose Tissue, Subcutaneous Adipose Tissue and Skeletal Muscle Using Contrast Enhanced Ultrasound (CEU); A Repeatability Study

The purpose of this study is to test a method of imaging (taking a picture) of the abdomen (belly), neck, thigh and calf (lower leg) areas of the body, using ultrasound along with a drug which makes the pictures look clearer. Ultrasound is a type of imaging that uses sound waves to create a picture of the inside of the human body. Two sets of pictures will be taken on two different days to see if the results are the same each time.

DEFINITY® is a drug given intravenously (through the vein). DEFINITY® is approved by the FDA to be used as an ultrasound contrast agent (makes the pictures look clearer) while taking pictures of the heart. In this study, DEFINITY® will be used while taking pictures of blood vessels in your abdomen (belly), neck, thigh and calf (lower leg). Since this use of DEFINITY® is different than the use approved by the FDA, this study will be performed under an FDA Investigational New Drug (IND) application.

Inclusion Criteria:

1. Men and non-pregnant/lactating women between the ages of 18 and 45;
2. Lean (BMI ≥18 and ≤25) or Obese grade I-II(BMI>30 and ≤35)
3. Provide written informed consent and sign HIPAA Waiver of Authorization
4. Be able and willing to follow all instructions and attend all study visits

Exclusion Criteria:

Subjects must not have been diagnosed with:

1. Coronary artery disease
2. Congestive heart failure
3. Congenital heart disease (Right-to-left, bi-directional, or transient right-to-left cardiac shunts)
4. Hypersensitivity to perflutren
5. Renal disease
6. Chronic obstructive pulmonary disease or Asthma
7. Primary or secondary pulmonary hypertension
8. Obstructive sleep apnea
9. Thyroid disease
10. Vasculitis
11. Peripheral arterial disease.
12. Cancer
13. Any type of immunosuppression
14. Any active infection (systemic or of the underlying skin or subcutaneous tissue).
15. Taking any prescribed medication for hypertension, dyslipidemia or diabetes.
16. Current or past smoking in the last 12 months.
17. Positive urine pregnancy test
18. Creatinine (Cr) above 1.4 mg/dl on screening evaluation
19. Hemoglobin (Hb) less than 10 mg/dl on screening evaluation
20. Aspartate Transaminase (AST) or Alanine Transaminase (ALT) two fold above upper limit of normal on screening evaluation