Pilot Study-Magnetic Resonance Imaging for Global Atherosclerosis Risk Assessment

Overview

Cardiovascular disease (CVD) remains the leading cause of death in the United States, and improved CVD risk assessment is needed for personalized medicine. Atherosclerosis measures including plaque volume and adverse plaque features have prognostic value. Novel techniques have been developed for assessing carotid, coronary, and femoral atherosclerosis using magnetic resonance imaging (MRI) methods that are rapid and reproducible, have improved spatial resolution, and do not require contrast media, making atherosclerosis assessment in multiple vascular beds feasible during a single MRI session. This pilot research will provide preliminary data to develop an innovative global atherosclerosis measure including carotid, coronary, and femoral vascular beds, for assessing cardiovascular risk and for monitoring atherosclerosis response to therapy. 20 participants will be recruited in one year.

Description

There are up to 2 study visits in this study.

During the first visit, the investigators will obtain non-contrast MRI (carotid, coronary, and femoral) in 20 subjects with known coronary atherosclerosis but varying degrees of CVD risk.

1. 5 asymptomatic subjects with lower CVD risk (recent coronary artery calcium score [CACS] 10-299)
2. 5 asymptomatic subjects with higher CVD risk (CACS 300-1000)
3. 5 subjects with known coronary atherosclerosis and stable angina
4. 5 subjects with known atherosclerosis and recent acute myocardial infarction

The investigators will measure plaque volume and assess adverse plaque features (intra-plaque hemorrhage, positive remodeling, lesion eccentricity) in the three vascular beds.

Eight of these subjects with evidence of large plaque burden by MRI will be asked to return for a simultaneous positron emission tomography (PET)-MRI imaging with 18F-sodium fluoride (18F-NaF) of their carotid, coronary, and femoral arteries, in which 18F-NaF uptake in plaque will represent micro-calcifications, which is associated with high-risk plaque.

In all 20 subjects, the investigators will also measure the following biomarkers which have been shown to be useful for CVD risk assessment of atherosclerosis: LDL, HDL, lipoprotein(a), apolipoprotein B/A-1 ratio, hemoglobin A1c, adiponectin, and highly sensitive C-reactive protein. The investigators will also calculate their estimated 10-year and lifetime atherosclerotic CVD risk (American Heart Association), Framingham 10-year CVD risk, and Reynolds 10-year CVD risk scores.

We aim to obtain the second scan within 3 months of the first visit; thus, the subjects will participate in the study for approximately 3 months.

All the procedures are research-related. The research visit will take approximately 3 hours, and there will be maximum two visits. There are no collaborations with other sites.

Eligibility

Inclusion Criteria:

1. Men and women with evidence of coronary atherosclerosis based on a recent CACS 10-1000 or an invasive or CT coronary angiogram (within 6 weeks of recruitment)
2. No planned revascularization procedures

Exclusion Criteria:

1. Contraindications to MRI
2. Pregnant and lactating women
3. Body mass index (BMI)>40
4. Active smoking
5. Resting heart rate>75 beats per minute
6. Arrhythmia
7. Prior carotid/coronary/peripheral revascularization
8. Life expectancy <5 years
9. Allergy to animal dander
10. Severe asthma