Heart disease is the top killer of women in the United States, killing even more women than men.

But when researchers asked women to name the most common cause of death for women, many said breast cancer.

Jane Gianino, 63, of Novato, California, had already survived breast cancer when she learned she had cardiovascular disease.

Gianino was gearing up to participate in a breast cancer awareness walk. She thought she had strained muscles in her legs, which grew sore when she walked.

Gianino was lucky in at least one sense. Her general practitioner recognized immediately the problem was blood flow. She was diagnosed with peripheral artery disease (PAD), which is often a precursor to coronary artery disease.

She had stents put into the arteries in her legs to bypass blockages at Stanford Medical Center in Palo Alto. On a recent afternoon, she said she was feeling fine as she prepared to make biscotti — though she still worries her cancer may come back.

Learn more: What is PAD? »

Women and their doctors, so aware of breast cancer, often fail to recognize symptoms of heart disease. February is American Heart Month.

“For a long time, PAD as well as coronary heart disease weren’t in line in terms of thinking that it’s a disease that we need to think about for women,” said Dr. Venita Chandra, the Stanford surgeon who operated on Gianino.

Culturally, we’ve been taught to think of heart disease as a man’s problem. But the consequences of those misperceptions are deadly.

Since 1984, death rates from heart disease have been higher among women than men.

Women wait longer to get diagnosed with PAD and heart disease, including angina and heart attack. They are less likely to receive drugs to treat angina or a heart attack. And they’re less likely to be referred for an ECG, a bypass, or stenting surgeries.

“When women are coming in with heart attacks often times they’re missed, there’s a delay in diagnosis. People think a 40-year-old woman is not supposed to have a heart attack,” said Dr. Abha Khandelwal, a cardiologist at the Stanford Women’s Heart Health Clinic.

Dr. Nisha Parikh, an assistant professor of cardiology at the University of California, San Francisco (UCSF), tells the story of a fit woman in her mid-30s who came into the emergency room with nausea and chest pain — a classic symptom of a heart attack.

Doctors attributed her troubles to her stomach. But when she came back later that day insisting it was more than indigestion, they saw she had angina, a precursor to a full-blown heart attack.

Khandelwal tells a similar story of a woman who had a rare type of heart attack called a spontaneous coronary artery dissection, in which the artery ruptures.

Patients like these remind Parikh and Khandelwal that doctors need to do better at recognizing and treating heart conditions in women. Because the patients were young, fit, and female, doctors failed to consider heart disease as a possible diagnosis.

Women Report Different Symptoms

The patients Parikh and Khandelwal remember both complained of nausea. Although chest pain is the most common symptom for both men and women, for women it’s not always their main complaint.

“With women oftentimes it’s not the first or most prevalent symptom,” Khandelwal said.

Heart disease also generally shows up in women about 10 years later than it does in men, doctors said.

“This may be another reason why we’re getting to them a little later,” Parikh said.

Women are more likely to tell doctors they feel nauseous, are tired, feel tingling in the jaw, or are short of breath. These symptoms can lead doctors down the path to a faulty diagnosis. Some women with PAD are simply ignored, Chandra said.

Keep Reading: How Heart Disease Affects Women »

Cultural Perceptions Are Changing

But cultural bias is also a big part of the problem. Doctors just don’t put cardiovascular disease on the short list of diagnoses when they’re treating female patients.

“Historically we sort of labeled it as a man’s disease,” said Parikh. “Back in the ‘Mad Men’ days, public health pamphlets geared toward women would be like ‘Here’s how you can help take care of your husband’s heart disease,’ when in fact heart disease is and was also the number one cause of death in women.”

Doctors need to be educated that heart conditions should be high on their list of possible diagnoses for women, like Gianino, who come to their offices with precursor complaints, and for women like the two Parikh and Khandelwal described, who come to the hospital in distress.

In the past decade, since influential studies on hormone replacement showed that estrogen doesn’t protect women from heart disease, as previously thought, doctors have begun to rethink women’s heart health.

At top-tier medical centers like UCSF and Stanford, doctors know to look for heart disease in women.

“But there’s still work to be done,” Khandelwal said.

For instance, the imaging tests that look for blockages in major arteries near the heart often miss blockages in smaller arteries, which are more common among women.

“When our women come into the hospital with angina, a lot of times when they do get these procedures, their arteries will look normal, or open. They are told they don’t have heart disease, but they still keep coming into the hospital, they keep experiencing chest pain,” Khandelwal said. “Oftentimes it’s not the large arteries that are blocked. It’s the small arteries, the microvasculature. Again, because our tests were developed for disease in men, they’re not as good at diagnosing all the causes that can occur in women.”

Women: Listen to Your Heart

So what can women do? Especially those over 50, who are at highest risk, need to remember that heart disease can affect them and seek medical attention immediately for any discomfort in the chest.

“Chest pain is something to be taken seriously. Older women still don’t recognize that they could be having a heart attack,” said Parikh. “That’s the age group that was probably newly married and getting those pamphlets in the 60s.”

But the best thing to do is to manage risk factors. Heart attacks can kill without any prior symptoms. Among men who die of sudden heart attacks, half have had no symptoms. Among women, that figure jumps to 65 percent. 

The good news is that the risk factors are the same for men and women, and are well known. They include a family history of heart disease, excess weight, poor diet, high LDL or “bad” cholesterol, diabetes, and lack of exercise.

Women who have premature or low birth-weight babies are also at increased risk for heart disease, Parikh told Healthline.

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