ORLANDO, Nov. 11 -- Many eligible heart attack patients are not receiving appropriate artery opening treatments -- including the powerful clot-busters -- according to a study reported today at the American Heart Association's 70th Scientific Sessions.
The study found that certain groups of people experiencing a heart attack -- women, minorities, elderly, and those suffering from severe heart attacks -- are less likely to receive clot-busting drugs and other medical procedures used to restore blood flow to the heart.
"The inescapable conclusion is that women and those with more health problems get less care. Women, people who are elderly, minorities and those with previous heart attack or stroke appear underserved. With a million heart attacks each year, we're talking about a lot of people who could benefit, but who don't at present," says Hal V. Barron, M.D., assistant clinical professor of medicine/cardiology at the University of California, San Francisco, and clinical scientist at Genetech. He led the research team.
"We don't know the reasons for this," Barron says. "There may be a difference in the attention women receive during their heart attack or a difference in the way their symptoms are reported or perceived by health-care professionals. Perhaps some of these individuals are refusing therapy. Maybe treating physicians perceive that those patients at highest risk for death don't benefit, even though large scale trials have shown that these therapies improve survival for virtually all individuals."
The team also found strong regional variations in the use of clot-busting drugs, angioplasty and bypass surgery. About 70 percent of heart attack sufferers in the Mid-Atlantic States received artery-opening treatment -- the lowest percentage of any region. Individuals living in the Rocky Mountain region were most likely to receive therapy, with 81.5 percent treated.
The study involved 84,663 patients in 1,470 hospitals participating in the second National Registry of Myocardial Infarction trial (NRMI 2), designed to collect, analyze, and report local and national heart attack practice patterns.
The researchers used the registry to describe trends in heart attack treatments in certain populations by examining how often blood flow-restoring therapies -- "clot-busting" drugs, angioplasty and bypass surgery -- are used and in which populations.
In angioplasty, a balloon-tipped catheter is inserted into the artery and the balloon is inflated, compressing the blockages and enlarging the inner diameter of the blood vessel. Coronary artery bypass involves taking a blood vessel from another part of the body and constructing a detour around the blocked area of the coronary artery. The researchers reported that of the 84,663 patients studied, 64,344 received one of the three major forms of "reperfusion" artery-opening treatments after their heart attack and 20,319 did not.
Individuals over age 75, those with prior heart attack, stroke or congestive heart failure, and those with diabetes also were less likely to be treated with clot-dissolving drugs than those without such risk factors, although all were "apparently eligible" for the therapy. "The more likely a person is to die from their heart attack, the less likely that person will receive this type of therapy. An explanation for these observations remains unclear and further investigation is underway," says Barron.
Current guidelines from the American Heart Association and the American College of Cardiology are specific about which individuals should receive thrombolytic drugs, angioplasty or bypass surgery. "The study shows that in many cases the guidelines are not being followed," says Barron.
Co-authors are Laura J. Bowlby, Tim Breen, Genetech Inc, South San Francisco CA; William J. Rogers, John G. Canto, University Of Alabama Medical Center, Birmingham AL; Alan J. Tiefenbrunn, Washington University, St. Louis MO; Nisha C. Chandra, Francis Scott Key Medical Center, Baltimore MD; William J. French, Harbor UCLA Medical Center, Torrance CA; W. Douglas, Henry Ford Medical Center, Detroit MI.
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