WASHINGTON -- Each year 80 to 100,000 Americans die suddenly from heart attacks without ever having had any symptoms of heart disease. In some cases, the victims of these unheralded sudden cardiac deaths had been taking dietary supplements containing ephedrine. In a new study in the Oct. 26, 2004 issue of the Journal of the American College of Cardiology, researchers show how ephedrine can cause sudden cardiac death in an animal model of asymptomatic heart disease.

"For our experiment, we went to the local health food store, bought ephedrine supplements and gave our animals the dose recommended on the label," said Philip B. Adamson, M.D., associate professor in the department of physiology and the department of medicine - cardiovascular diseases at the University of Oklahoma Health Sciences Center in Oklahoma City, Okla. and lead author of the study. "Ephedrine mimics the sympathetic nervous system, the part of the nervous system that makes the heart beat stronger and faster. In past experiments on obese, otherwise healthy individuals ephedrine did not raise their heart rates when they were either at rest or exercising." Dr. Adamson spoke today at the American Medical Association's 23rd Annual Science Reporters Conference in Washington D.C.

"When we gave healthy animals ephedrine, we found exactly the same thing," Dr. Adamson said. "But the moment they developed a blockage in their heart artery, which we are able to cause reversibly, their heart rates went through the roof. It was the response to ischemia, a condition where there is a blockage of the heart's blood supply that was exaggerated by ephedrine."

"In ischemic heart disease, the blood supply to the heart becomes constricted, causing damage to the heart muscle and heart disease. However, sometimes the condition develops without any symptoms, leading to a sudden heart attack. Death can be the first symptom people with ischemic heart disease experience," Dr. Adamson said. "We wanted
'"/>

Contact: Christine M. Feheley
cfeheley@acc.org
301-581-3425
American Medical Association
14-Oct-2004

Page: 1 2
Related medicine news :

1. Rheumatoid arthritis patients at higher risk for unrecognized heart disease and cardiac sudden death
2. Least protection offered to those most at risk of sudden cardiac death
3. Study confirms ICDs more effective in preventing sudden cardiac death than medical therapies
4. Pacemakers could protect patients with epilepsy from sudden unexplained death
5. Protection from sudden cardiac death in women may be linked with a diet rich in alpha-linolenic acid
6. OHSU researcher finds genetic explanations for some previously unexplained sudden cardiac deaths
7. New drug prevents arrhythmias that cause sudden cardiac death
8. Major risk factors identified for sudden infant death syndrome
9. Genomics research: New genetic hit list may underlie susceptibility to sudden cardiac death
10. Study shows younger women dont die a sudden cardiac death for the same reasons as men
11. Estrogen replacement increases risk factors for arrhythmia and sudden death