Using positron emission tomography (PET), the medical isotope 15O-water and cold pressor tests, Japanese researchers were able to detect the beginnings of atherosclerosis - before the disease became clinically evident.
These results were released during Society of Nuclear Medicine's 53rd Annual Meeting in San Diego.
This revelation will allow physicians to advise high-risk patients--who show no cardiovascular symptoms--to make lifestyle changes modifications or to undergo medical treatment, said Masanao Naya, a physician at Hokkaido University Graduate School of Medicine in Sapporo, Japan. In addition, researchers determined that elevated levels of interleukin-6--one of the inflammatory chemicals produced by endothelial cells and that has been associated with an increased risk of heart disease--is "a major determinant" of coronary endothelial dysfunction, especially in individuals with high blood pressure.
Atherosclerosis is a slow, progressive disease that begins with damage to the innermost layer of the artery--the endothelium--and buildup of fatty substances, cholesterol and cellular waste products in the inner linings of arteries, which carry oxygen-rich blood to the heart, brain and other parts of the body. The endothelium can be damaged by such factors as elevated levels of cholesterol, high blood pressure (hypertension), smoking and obesity. Over time, plaques can narrow coronary arteries, allowing less blood to flow to the heart muscle. Rupture of these plaques may result in heart attack and death, said the co-author of "Determinants of Coronary Endothelial Dysfunction in Hypertensive Patients."
Coronary endothelial dysfunction--which occurs when blood vessels aren't flexible enough to expand in response to increased blood flow--is the central feature of this dreaded disease. Coronary endothelial dysfunction precedes cardiovascular events and is reversible, making its early detection important, said Naya. He explained, "We can select high-risk patients with endothelial dysfunction using blood sample analysis at an early stage of atherosclerosis, then start medical treatment or lifestyle modification." More than 71 million Americans have one or more forms of cardiovascular disease, the single leading cause of death in this country.