Tracy Solomon Clark is outgoing and energetic — a former fundraiser for big companies and big causes. As she charged through her 40s she had "no clue," she says, that there might be a problem with her heart.

It was about six years ago — when she was 44 — that she first suffered severe shortness of breath, along with dizziness. She figured she was overweight and overworked, but never considered heart disease.

"That was the furthest thing from my mind," Solomon Clark says. "I was young!"

But it was her heart. Her doctor sent her to the hospital emergency room, where physicians diagnosed a blockage in a key artery. They inserted a stent to open it up and ease blood flow to her heart.

Ultimately Solomon Clark, who lives in Gardena, Calif., got several more stents to treat what turned out to be serious cardiovascular disease. Last year she had double-bypass surgery to replace the left main artery of her heart.

She's not alone, according to Dr. Noel Bairey Merz, who directs the Barbra Streisand Women's Heart Center at Cedars-Sinai Medical Center in Los Angeles, says she's not surprised by Solomon Clark's experience. Bairey Merz often meets young and middle-aged women who have no idea they are at risk for heart disease and a heart attack.

She and colleagues recently surveyed 1,011 women ages 25 to 60, a random sampling from across the U.S. Only about half of those interviewed knew that heart disease is the leading threat to women's lives, the scientists found. Many thought breast cancer poses a bigger risk. They were wrong.

Every year in the U.S. about 40,000 women die from breast cancer, according to statistics from the Centers for Disease Control and Prevention. Meanwhile, roughly 10 times that number die from heart disease.

Greater awareness and advances in detection and treatment have dramatically decreased breast cancer deaths over the past few decades, Bairey Merz explains. But heart disease now claims the life of 1 in every 4 women.

Many women with heart disease could benefit from effective treatment, including aspirin, statins, beta blockers and the like, says Dr. Laxmi Mehta, a cardiologist at the Ohio State Wexler Medical Center. But they can be helped only if they are diagnosed.

After the stent was placed, Solomon Clark continued to have periodic bouts of dizziness, shortness of breath and even a little pain. The symptoms were eventually traced back to continuing heart trouble.

But not right away. When she returned to an ER to have the symptoms checked out, tests suggested no new blockages, and the emergency room doctors told her she might just be suffering an anxiety attack.

Mehta chaired a committee of the American Heart Association that this year released the organization's first scientific statement on the problem of heart attacks among women.

Even after a heart attack, Mehta says, women are less likely than men to be referred to cardiac rehabilitation programs, though these programs significantly reduce the chances of a second heart attack.

Part of the reason women are misdiagnosed or not diagnosed at all is because heart disease looks a lot different in women than it does in men, she says. And men have been the focus of most heart disease research.

For example, men are more prone to blockages in major arteries — these are relatively easy to spot on an angiogram, and are more likely to prompt timely diagnosis, Mehta says.

Women, on the other hand, are more likely to have problems with tiny arteries embedded in the heart, she says. These smaller blood vessels often are not visible on angiograms, and also don't fill up with plaque.

"They don't have enough of a wall to build up plaque," says Bairy Merz. "That's how tiny they are." But these small arteries can lose flexibility and run into problems — constricting too much and cutting off blood flow to the heart.

In her survey, Bairey Merz found that 74 percent of the women had at least one heart disease risk factor, such as high blood pressure, high cholesterol, diabetes, irregular menstrual periods, early menopause or a family history of heart disease. Yet only 16 percent reported having been told by a doctor that they had an elevated risk.

Instead, Bairey Merz says, the doctors, who also were surveyed by the researchers, were more concerned about their patients' weight and breast health than heart disease.

All primary care doctors should routinely assess a woman's risk for heart disease, Mehta says. And if they don't, women should take the lead and bring up the subject of heart disease and their individual risk. (You can start by using this online risk calculator.)

Pay attention to your body, Mehta tells her patients. "If something seems out of the ordinary, it's best to seek medical attention, especially if something is occurring only with exertion — or worsening with exertion.

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