Tests for Heart Disease
Many tests measure cardiac health, but some are better at detecting disease in women. If your symptoms or risk factors warrant a workup, ask your doctor about these three assessments.
Conventional stress testing, which uses electrodes and a blood pressure cuff to measure how well your heart works while exercising, can lead to false positive results in women. These abnormal results may be explained by differences in female heart rhythms as well as estrogen levels. A stress echocardiogram uses ultrasound to show the heart’s motion at rest and at peak exercise and is more accurate for women, says Marianne J. Legato, MD, founder of the Foundation for Gender-Specific Medicine, in New York City. This test is widely available.
CT Scan for Coronary Calcification
A CT (computed tomography) scan uses x-rays to produce multiple images of the heart and its vessels to determine how much calcium, a component of plaque, has accumulated. This noninvasive test can detect calcium buildup before it starts to significantly narrow the arteries, says cardiologist Sharonne Hayes, MD, of the Mayo Clinic in Rochester, Minnesota. That’s especially important for women, who don’t develop plaque as early or as extensively as men. The scan results are reported as a number known as a calcium score. Your score will be evaluated based on your age and gender; if it’s high, you may need treatment. This test is available at many large hospitals.
Screening Vascular Ultrasound
Another tool for detecting plaque, this test can identify patients with cardiovascular disease before they show any symptoms, according to recent research. A screening vascular ultrasound (SVU) enables doctors to zoom in and see the blood vessels at a resolution of .2 millimeters, versus two millimeters for an angiogram. SVU may even be able to detect problems in women who were cleared by the Framingham Risk Score, the traditional method for measuring heart disease risk, in time to prevent it. John E. Postley, MD, of Columbia University, uses this noninvasive test on female patients, because, he says, it "can pick up early atherosclerotic disease." Ask your doctor if you’re a candidate for this promising new test.
The Reynolds Risk Score
Many doctors use online tools to assess your risk of heart attack or stroke. But the traditional Framingham score is not as accurate for women. Forty to 50 percent of women classified as intermediate risk by Framingham turn out to be at higher or lower risk when assessed by the new, more woman-centered Reynolds Risk Score (www.reynoldsriskscore.org). And 80 to 90 percent of asymptomatic women are classified as low risk by Framingham although they have a one in two chance of dying from cardiovascular disease.
Both models take into account traditional risk factors, such as high cholesterol, high blood pressure, and smoking that predict heart disease in most men and women, but the Reynolds Score incorporates two additional factors (c-reactive protein and parents’ history of premature heart disease) that are not part of Framingham. The reason? Not all women have traditional risk factors — and the women who do may be affected by them more severely than men are. "Smoking, low HDL, high triglycerides, and obesity are worse for us," notes New York cardiologist Nieca Goldberg, MD. The reason may lie in basic physiological differences, such as women’s narrower arteries, says Rajat Sethi, PhD, of Texas A&M Health Science Center. These subtle differences can dramatically affect the accuracy of risk assessments.
"The point is not to diagnose heart disease but to prevent it," explains New York cardiologist Suzanne Steinbaum, DO, "so ask to be tested for the risk factors that are part of the Reynolds Score."
More on Heart Disease
Originally published in MORE magazine, September 2007.