Heart disease silently kills women: Why?

(CBS/AP) Heart disease may stand out as America's leading cause of death, but the No. 1 killer may be a silent killer among women. Nearly two-thirds of women who die suddenly from heart disease report no previous symptoms, compared with half of men. Women are also more likely to die the year after a first heart attack.

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More than 40 percent of women also don't realize that heart disease is the number one female killer - it strikes one in three women every year.

Why the gender gap?

A new report claims not enough progress has been made studying gender differences in heart disease. According to the report, only a third of heart-related studies focus on how each gender responds, even though federal policy states all should.

"A woman's heart is her major health threat, and everyone who takes care of a woman has to realize that," says Emory University cardiologist Dr. Nanette Wenger, who co-authored the report.

Make no mistake: Heart disease is the leading killer of men, too. The illness is more prevalent in men, and tends to hit them about a decade earlier than is usual for women. But women face some unique issues, according to the report from the nonprofit Society for Women's Health Research and WomenHeart: The National Coalition for Women with Heart Disease. While chest pain is the most common symptom among men and women, women are more likely than men to experience other symptoms such as shortness of breath, nausea and pain in the back or jaw.

As far as triggers go - being a couch potato and eating lots of junk food is just as bad for a woman's heart as a man's. High cholesterol will clog arteries, and high blood pressure can cause a stroke.

But here's one problem: Even if a test of major heart arteries finds no blockages, at-risk women can still have coronary microvascular disease - a serious problem that's less common in men, in which small blood vessels that feed the heart become damaged so that they spasm or squeeze shut, Wenger explains.

Doctors who suspect microvascular disease prescribe medications designed to make blood vessels relax and blood flow a bit better, while also intensively treating the woman's other cardiac risk factors. But Wenger says it's not clear what the best treatments are.

Another issue: There's been a slight increase in deaths among women younger than 45. Plus, high blood pressure, diabetes or related complications during pregnancy - a growing worry as more women start their pregnancies already overweight - aren't just a temporary problem but increase those mothers' risk of heart disease once they reach middle age. The report says too few doctors consider these risks.

One young patient says women need to know more about heart disease - and to get pushy about any symptoms.

Essence Harris of New Orleans was only 30 when she started experiencing shortness of breath and feeling chest pains during daily workouts. Her primary care doctor thought it was panic attacks. A cardiologist found no obvious risk either - her cholesterol and blood pressure were normal - but ordered a stress test that signaled her heart fears were right. A further exam found severe blockages in two arteries that required stents to prop open.

Now 37, Harris says doctors' best guess is that a stressful lifestyle - a single mother, a full-time job, a part-time personal trainer, and studying for an advanced degree all at the same time - left her vulnerable even without obvious risk factors. Had she not been so fit, they said, her heart might not have held out as long before symptoms appeared. She's learned to be more laid-back, along with a healthier diet and keeping up that exercise.

"Listen to your body," she advises other women. "Nobody knows you better than you."