In as many as 3 million U.S. women with coronary heart disease, cholesterol
plaque may not build up into major blockages, but instead spreads evenly throughout
the artery wall. As a result, diagnostic coronary angiography reveals that these
women have ?clear? arteries — no blockages — incorrectly indicating
low risk. Despite this, many of these women have a high risk for heart attack,
according to newly published research from the National Institutes of Health.
In women with this condition, called coronary microvascular syndrome, plaque
accumulates in very small arteries of the heart, causing narrowing, reduced oxygen
flow to the heart, and pain that can be similar to that of people with blocked
arteries, but the plaque does not show up when physicians use standard tests.
As a result, many women go undiagnosed, according to findings from the National
Heart, Lung, and Blood Institute?s (NHLBI) Women?s Ischemia Syndrome Evaluation
(WISE) study. Insights from the study are published in a special supplement to
the February 6 issue of the Journal of the American College of Cardiology,
available online January 31.
"When a diagnosis of this condition is missed, women are not treated for their
angina and high cholesterol and they remain at high risk for having a heart attack," said
NHLBI Director Elizabeth G. Nabel, M.D. "This study and the high prevalence of
coronary microvascular dysfunction demonstrate that we must think out of the
box when it comes to the evaluation and diagnosis of heart disease in women."
The National Institutes of Health initiated WISE in 1996 to increase scientific
knowledge about ischemic heart disease in women. WISE aimed to develop accurate
diagnostic approaches for ischemic heart disease detection in women, to better
understand the ways in which heart disease develops in women including the significance
of ischemia without coronary blockages in women, and to evaluate the influence
of hormones, on ischemic heart disease development and diagnosis.
'So much of our understanding of the underpinnings of heart disease and heart
attack, and the basis for our standard methods of diagnosis and treatment are
the result of research conducted on men,? said C. Noel Bairey Merz, Cedars-Sinai
Medical Center and the WISE study chairperson. ?Through clinical experience,
many critical questions arose about how the disease may manifest differently
in women, and how diagnostic techniques may need to be used differently in order
to prevent more heart attacks and save lives."
WISE investigators found that the majority of women with ?clear? angiography
who are not diagnosed will continue to have symptoms, a declining quality of
life, and repeated hospitalizations and tests.
"Through WISE, we have made tremendous progress toward better understanding
of heart disease in women. Too often women are tested again and again, go untreated,
and still have high risk for heart attacks," said George Sopko, MD, NHLBI project
officer for WISE. "As clinicians we must systematically examine women for evidence
of any blockages and initiate intensive treatment for their risk factors."
Authors of six review papers providing insight on WISE conclude that the study
has provided the groundwork for additional controlled clinical studies of diagnostic
tools and treatments in women with ischemic heart disease.
Additional study conclusions from WISE appear in the same JACC edition:
- Identifying Candidates for Exercise Stress Testing: Using the evaluative
tool Duke Activity Status Index (DASI) in women with heart disease symptoms
prior to stress testing can help determine who would be eligible for an exercise
stress test versus a stress test using intravenous medications to increase
the heart load instead of exercise. Current guidelines offer physicians little
guidance on how to identify women who would not be able to sufficiently complete
the exercise test. The DASI has been previously validated as a useful tool
for determining functional capacity.
- Low Coronary Flow and Scores on Function Test Indicate Poor Outcomes:
Women who have low DASI scores also have lower coronary flow velocity, a combination
which may explain the poor outcomes seen for women with heart disease but no
- Role of Pre-menopausal Hypertension in Disease Risk: Women who have
high blood pressure before menopause, especially high systolic blood pressure,
should be considered at a higher risk and treated accordingly.
To interview a scientist about this study, contact the NHLBI Communications
Office at (301) 496-4236.
NHLBI is part of the National Institutes of Health (NIH), the Federal Government?s
primary agency for biomedical and behavioral research. NIH is a component of
the U.S. Department of Health and Human Services. NHLBI press releases and
other materials including information about women and heart disease are available
online at www.nhlbi.nih.gov.
The National Institutes of Health (NIH) — The Nation's Medical Research
Agency — includes 27 Institutes and Centers and is a component of
the U. S. Department of Health and Human Services. It is the primary Federal
agency for conducting and supporting basic, clinical, and translational medical
research, and it investigates the causes, treatments, and cures for both common
and rare diseases. For more information about NIH and its programs, visit http://www.nih.gov.