How's Your Heart? What You Need to Know About Coronary Disease

By now we all know that the symptoms of heart disease are—dangerously—far more subtle in women than in men. Instead of the crushing chest pain and cold sweat that would make a man grasp for the phone, women might notice simply indigestion or fatigue. For about two out of five of us who have heart disease, “the first symptom is death,” says Lori Mosca, MD, PhD, director of preventive cardiology at New York–Presbyterian Hospital.

Medicine is only just learning that the difference in symptoms reflects differences in the disease itself. For example, men tend to form big, easily observed clumps of plaque (the buildup of cholesterol, calcium, and other deposits that narrows blood vessels and causes clots). But as many as three million women have a condition called microvascular disease, in which the plaque spreads evenly throughout the artery walls and accumulates in the tiny tributaries—often making them rigid—at the end of the stream of arteries feeding the heart, where it's frequently not picked up by traditional angiograms, according to WISE (Women's Ischemia Syndrome Evaluation), an ongoing study launched by the National Institutes of Health in 1996. This is partly why the gold standards for catching heart disease in men—like the angiogram and the treadmill stress test—just don't work as well in women.

Fortunately, new insights are leading to better high-tech scans for us. One thing about heart disease that's the same for both sexes: It's the number one cause of death.
 
So here's what you need to know if...

You're perfectly healthy
For women age 20 and over, the American Heart Association recommends the following:

• At least every two years, measure blood pressure, pulse, waist size, and body mass index.
  
  
• At least every five years, get both your blood sugar and fasting blood lipids (total cholesterol, HDL, LDL, and triglycerides) tested.

You feel fine but have risk factors
Estrogen helps protect the heart during childbearing years, giving women a definite advantage over men before menopause, says Robert Bonow, MD, chief of the division of cardiology at Northwestern Memorial Hospital in Chicago—an edge that can be erased by risk factors including:

• High blood pressure,abnormal cholesterol levels, diabetes, a waist larger than 35 inches, a BMI of 25 or greater, or inactivity.
  
  
• Smoking—it cranks up risk as much as an extra 92 pounds would, according to the WISE study.
  
  
• Family history of stroke or heart disease, especially in a father or brother before age 55 or mother or sister before age 65.

If you have any of these risk factors, you may want to talk to your doctor about getting one of the relatively new blood or imaging tests that can offer a clearer picture of your heart health—and whether you should start taking drugs or make lifestyle changes. Keep in mind that at this point, the tests are more suggestive than definitive.

Blood tests: C-reactive protein (CRP) is the most established of the blood tests and the one you should probably get if you're not showing any symptoms yet. It can pick up problems even in women with low levels of LDL, or “bad,” cholesterol (up to half of all heart attacks occur in people with normal LDL levels).

Imaging tests: A new technique called a CT angiogram (or cardiac CT) is another test you might consider, says Mehmet Oz, MD, director of the Cardiovascular Institute at Columbia University Medical Center in New York City, especially if you have risk factors—like smoking or obesity—that you're willing to change. An image constructed from 64 pictures, or slices, presents a fairly precise idea of how blood is flowing through the arteries and whether calcified or soft plaque is causing restrictions.

Other imaging tests that may be offered at this stage are an ultrasound of the carotid artery or electron beam computed tomography (EBCT), an X-ray procedure that scans for calcium in the heart's vessels. Oz believes the CT angiogram is superior to both, pointing out that another difference between the sexes is that unlike men, women tend not to deposit calcium in their plaque (which actually makes it more likely to rupture)—so the danger for us would be less visible on an EBCT. A recent review in the Journal of the American Medical Association found scant evidence that this scan leads to better outcomes.  

What to do if you have symptoms
When carrying groceries up one flight of stairs prompts out-of-the-ordinary breathlessness or a burning pain anywhere, front or back, between your belly button and chin, you may be noticing signs of heart disease. Other symptoms include unusual fatigue, dizziness, nausea, or a tightness in the chest.   For women, cardiologists are turning to a new generation of diagnostic techniques. You should always start with either an echocardiogram or nuclear stress test, says Oz.

Echocardiogram: This is basically an ultrasound of the heart, usually conducted by passing a wand across your chest.

Nuclear stress test (also called cardiac or myocardial perfusion imaging or SPECT): With a small amount of an injected radioactive substance, a camera shows if the heart is receiving adequate blood supply when you're both at rest and at peak exercise on a treadmill or bicycle. The beauty of this test is that it can pick up evidence of small vessel disease.

CT angiogram: This test is becoming increasingly useful at the symptom stage as well, says Jennifer Mieres, MD, director of nuclear cardiology at New York University School of Medicine and chair of the American Heart Association's Cardiac Imaging committee. “The CT angiogram is especially good for looking at hidden plaque without calcium,” adds Oz.

Cardiac MRI: Another promising up-and-comer that uses a strong magnetic field and radio waves to create images of your heart. It's mostly available at big academic centers and may prove especially helpful in younger, perimenopausal women, says Mieres. “Ultimately, these tests are not going to save your life,” says Mosca. “You are going to save your life, because you are going to be committed to a heart-healthy lifestyle.” While a recent national survey pointed out that a mere 3 percent of American adults fully follow heart-healthy habits, we all know the drill. Give up smoking. Choose foods wisely. Stay at a healthy weight. And be active for at least 30 minutes on most days. Says Mieres: “Small steps make a difference.”

If persistent symptoms go undiagnosed, don't give up. “Everybody's looking for the magic test, and we don't have that,” says Nieca Goldberg, MD, chief of women's cardiac care at New York's Lenox Hill Hospital. “Find a doctor who's listening.”

Alison Motluk is the Toronto correspondent for The New Scientist magazine.