Coronary artery disease patients who tested positive for C. pneumoniae showed improved blood flow in the brachial artery (in the arm) and reduced blood levels of two known markers for endothelial dysfunction after five weeks of daily treatment with azithromycin. Patients given placebo did not improve.
Damage to the endothelium, the delicate lining inside arteries and other blood vessels, may lead to atherosclerotic plaques forming and eventually to chest pain (angina) and heart attacks. For several years heart researchers have tried to identify a specific bacterium or virus that might damage the endothelium. Once a microbe was identified, researchers tried to find an antibiotic that could eradicate it, says Juan Carlos Kaski, M.D., a co-author of the study and a professor of cardiovascular science at St. Georges Hospital Medical School, London. He says that C. pneumoniae proved to be a good candidate for this approach because it is a common infection and evidence of it has been discovered in plaque removed from arteries of people with coronary artery disease.
We have found in this study that treatment with azithromycin, an antibiotic used to treat C. pneumoniae infections, improved the function of the endothelium, says Kaski. The antibiotic thus appears to allow the artery to increase its caliber. This caliber change means the vessel widens in response to appropriate stimuli.
Forty males, average age 55, were enrolled in the study. All had documented coronary artery disease. They were randomly assigned to receive either azithromycin or placebo for five weeks. Flow-mediated dilation (FMD) of the brachial artery was measured at study entry an
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Contact: Carole Bullock
carole.bullock@heart.org
214-706-1279
American Heart Association
25-Feb-2002