When Bronx resident Carolyn Brown, 64, went to the hospital complaining of shortness of breath, a heart attack was the last thing on her mind.
"I thought I had a cold," she told ABCnews.com. "I always look for the signs of heart attack, chest pain, pain in your shoulder ... but I didn't have that," she says.
Even the doctors were unsure of whether Brown had suffered a heart attack. Blood tests suggested she may have had one, but an angiogram -- the imaging test that has been the gold standard for detecting heart attacks -- showed that her coronary arteries were clear. Her doctors sent her home without any of the medication -- such as statins to lower cholesterol and aspirin to thin the blood -- usually given to patients who have had a confirmed heart attack.
When Brown returned to the ER with much more severe symptoms in April 2010, the angiogram yet again revealed clear arteries, but this time doctors used a different kind of test -- an intravascular ultrasound, or IVUS -- that was more suited to detecting arterial plaque in women. Thanks to the IVUS, doctors found a dangerous block in Brown's neck, and she has since received the heart medication she needed all along.
Brown's case is not that unusual. Anywhere from 40,000 to 100,000 women every year with arteries that show up as clear on an angiogram suffer from a heart attack. Thirty-eight percent of the time, like Brown, they have the kind of plaque that doesn't show up on an angiogram, according to new research from the Cardiac and Vascular Institute at New York University Langone Medical Center. In these women, a rupture or ulcer in the plaque of their coronary arteries is behind their heart attack, but this rupture would not show up in standard angiogram.
"When a woman comes in with heart attack symptoms, but the angiogram is clear, doctors will sometimes turn around and tell them they didn't have a heart attack at all," says l Dr. Harmony Reynolds, the lead author of the study and an associate director of the Cardiovascular Clinical Research Center. "This is a big deal, because these patients are not getting the medication they need."
In the past, cardiologists have suspected that women with heart attack symptoms but clear angiogram results had the kind of plaque rupture identified in this study, but this research is the first to suggest that using additional ultrasound imaging testing could help determine that these women are in fact suffering from a heart attack, Reynolds says.
For years it seemed that heart disease was more of a health problem for men, but now doctors know that once women go through menopause, they are even more likely than men to have a heart attack. The way their heart disease and heart attack symptoms show up can be very different than in men, however, and this can make it difficult to detect these heart attacks using the standard tests.
"There is no place in cardiology that we fall farther short than in diagnosing heart disease in women," says Dr. Cam Patterson, chief of the division of cardiology at the University Carolina at Chapel Hill. "We ... know that women have different manifestations of heart disease than men do and the present study helps us to understand why -- the arteries of women's hearts can be affected by atherosclerosis that is not detectable on a stress test or angiogram, and yet can still lead to a heart attack," he adds.
"This is important because it helps us understand the gender gap in heart disease, but it is also scary because we don't have any easy way to identify these lesions in women before they rupture and cause a heart attack. It's fair to say that some women have diseased arteries in their hearts that are invisible ticking time bombs," he says.
It's too early in the research to suggest that all women with heart attack symptoms and clear angiograms should get tested with IVUS, Reynolds says.
What cardiologists and women should take from this research, however, is that "even if the 'regular' test shows no blockages, you are not totally out of the woods," says Dr. Christopher Cannon, a cardiologist at Brigham and Women's Hospital. Instead, doctors should treat these women's risk factors to lower their risk of a repeat cardiac event, he says.
"Women in Brown's situation should also make sure to ask their doctors if they should be put on medication to lower their cardiovascular risk," Reynolds says.