Natural History of Carotid Plaque as Determined by 3D Ultrasound

Study Overview
=================
Brief Summary
-----------------
This proposed follow-up study aims to recruit participants from the original BioImage cohort for a one-time follow-up examination. The repeat ultrasound scan of the carotid arteries will provide information on the natural history of carotid atherosclerosis and factors that contribute to plaque progression. Renewal of the HIPAA authorization will also be sought for 5 years to continue to monitor claims and other information for major cardiovascular events, other outcomes and healthcare utilization.

Detailed Description
-----------------
The design and objectives of the BioImage study (NCT00738725) have been published in detail. In brief, the BioImage study is investigating whether imaging of target arteries for subclinical atherosclerosis and measurement of ABI and circulating biomarkers add to the predictive value of traditional risk factor scoring systems, namely, the Framingham Risk Score. Enrollment in the BioImage study (January 2008 to June 2009) resulted in inclusion of 7,687 asymptomatic Americans ages 55 to 80 years from the Humana Health System resident in Chicago, Illinois, or Fort Lauderdale, Florida. Of these, 6,104 entered the imaging arm of the study. Analysis of the BioImage study cross- sectional baseline findings has yielded important novel findings related to presence and severity of subclinical atherosclerosis and the role of markers of subclinical disease to identify those at elevated risk for near-term atherothrombotic events. One of the striking novel findings in the BioImage study was the prevalence of subclinical atherosclerotic disease in the carotid arteries as determined by a novel 3D ultrasound method. 3D carotid imaging was used to identify lesions located in the cervical part of the common carotid arteries (CCA) and internal carotid artery. 3D carotid imaging was initially performed using a high- resolution, linear array 2-dimensional transducer and scanning the artery in cross-section, slowly moving the transducer manually in the cranial direction from the proximal CCA into the distal internal carotid artery (i.e., from the clavicle to jawbone). The resulting 10-s digital video clip of this manual 3D cross-sectional sweep was examined in the core ultrasound laboratory for the presence and quantification of plaque. In the second phase of the study an electromechanical transducer was used to accomplish a similar sweep, replacing the manual sweep with a controlled movement of the transducer. This ultrasound technique identified carotid plaques in 78% of cases. Carotid plaque burden was found to correlate stronger with CACS (chi-square 450, p < 0.0001) than did cIMT (chi-square 24, p < 0.0001)15. Analyses have indicated that subclinical atherosclerosis as determined by 3D ultrasound is an important risk factor with marked incremental value over conventional risk-factor based scores such as the Framingham Risk Score.

Official Title
-----------------
BioImage 2: Long-Term Follow-up of BioImage Study Cohort to Investigate Natural History of Carotid Plaque as Determined by 3D Ultrasound

Conditions
-----------------
Atherosclerotic Disease, Plaque, Atherosclerotic, Heart Diseases, Stroke, Cardiovascular Risk Factor

Intervention / Treatment
-----------------
* Device: Ultrasound 3D Imaging


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Participant in BioImage Study cohort with successful completion of carotid ultrasound imaging investigation Ability to travel to the location where the mobile research unit will be located (various locations in the Chicago area or Fort Lauderdale, Florida area) Written informed consent must be obtained before any assessment is performed Exclusion Criteria: Weight > 350 pounds Inability to comply with the visit to the study clinic and other study requirements
Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Ultrasound 3D Imaging<br>To investigate natural history of subclinical atherosclerosis as determined by 3D carotid ultrasound. | Device: Ultrasound 3D Imaging<br>* Carotid artery ultrasound will be used to: Determine plaque presence and plaque burden Presence of stenosis Additionally, Carotid Intima-Media Thickness (IMT) will be measured and aortic diameter will be measured by abdominal aortic ultrasound scanning. Ultrasound of the Abdominal Aorta will be used to determine the presence and severity of stenosis or aneurism.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To investigate natural history of subclinical atherosclerosis as determined by 3D carotid ultrasound. |  | 5 Years | 
| To evaluate the role of risk factors in disease progression of subclinical atherosclerosis. |  | 5 Years | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| To assess persistence of risk factors over an approximately 5-year time span between the baseline and the planned follow-up evaluation. |  | 5 Years | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
carotid atherosclerosis, plaque progression, Framingham Risk Score