Atherosclerosis in the Coronary and Carotid Arteries

Under the general hypothesis that atherosclerosis is a systemic disease; the purpose of this protocol is to compare coronary artery atherosclerotic abnormalities with carotid artery abnormalities. This is an NHLBI sponsored sub study to the Pfizer sponsored trial comparing atorvastatin or the combination of atorvastatin/CETP inhibitor as treatments for patients with coronary heart disease. The primary study is a multicenter, randomized, double blind, active-controlled study which uses intracoronary ultrasound to measure coronary plaque volume during the course of treatment. The scientific value of the NHLBI sub study will be the comparison of atherosclerotic abnormalities in two different vascular beds, the coronary artery and the carotid arteries. This study will examine correlations between invasive coronary measurements by intravascular ultrasound (IVUS), with 2-dimensional measurements of wall thickness by carotid intimal medial wall thickness (IMT), and with 3-dimensional measurements of carotid wall volume by MRI and 3D ultrasound. Secondary analysis will probe whether carotid plaque characteristics can predict atheroma regression. Secondary analysis will also assess the ability of noninvasive carotid measures to predict the degree of coronary regression determined in the coronary arteries by IVUS. It is important to note that the NHLBI study design remains blinded to the treatment group a subject is enrolled in since the sample size for a single center study is too small to detect the conservatively estimated additional benefit of combination atorvastatin/CETP inhibitor treatment over the already effective atorvastatin alone. Thus, the NHLBI sub study is primarily a pathophysiological study correlating carotid and coronary atherosclerotic changes as well as a technological comparison of IVU, carotid IMT, and carotid vessel wall volume by MRI. If successful, this study could provide the framework for following treatment trials of this nature with noninvasive tools, either ultrasound or MRI, in place of the accurate but invasive IVUS.

Inclusion criteria

Patients will be a subset of patients participating in the multicenter IVUS protocol.

Willingness to travel to the NIH to participate in the NHLBI MRI/IMT study.

Exclusion criteria

Pacemaker

Defibrillator

Brain aneurysm clips

Implanted active medical devices (neural stimulators, cochlear implants, insulin pumps, etc.)

Severe claustrophobia

Allergy to gadolinium based contrast agents (only excludes the gadolinium portion of the test)