Atherosclerosis is the fundamental process in coronary artery disease, stroke, and many other vascular diseases. It is responsible for more than half of the disease burden of the United States, with an annual cost of over $100 billion. This includes over 1.5 million myocardial infarctions annually. Atherosclerosis technically occurs in everyone 25 and over, but most remain asymptomatic for decades. This underscores the need to identify people at imminent risk for complications, since medication and lifestyle modification can reduce that risk. Well-established risk factors include hypertension, serum cholesterol and lipid levels, diabetes, obesity, diet, tobacco use, and a sedentary lifestyle. Serum levels of homocystine and C-reactive protein also predict risk. More recently, carotid intima-media thickness (CIMT) and the brachial artery reactivity test (BART), both obtained by ultrasound, have been shown to be powerful independent risk factors. Meanwhile, a skin sterol test called PREVU(x) provides a convenient, non-invasive, Point-of-Care assay.
At the root of atherosclerosis is a disturbance of the inner (intimal) wall of the artery. The process is complex, but one component is usually hypertension, which contributes to turbulent blood flow that traumatizes the intimal surface. Another component is inflammation, which combines with lipid, cholesterol, and calcium deposition to form plaques. These plaques accumulate over time, narrow the lumen inside the artery, and limit blood flow to distal structures such as the myocardium and brain. A plaque may also break and liberate pieces that block distal arterial branches. The final common pathway is insufficient blood supply to end organs, which may be acute or chronic.
Despite the central role of the artery in coronary and cerebrovascular disease, it has not been