Gender-based medicine conceals women’s heart
failure
Toronto - When it comes to heart failure in women, the
disease spectrum is different - very different, Dr. Peter
Liu told the Canadian Cardiovascular Congress 2008, co-
hosted by the Heart and Stroke Foundation and the Canadian
Cardiovascular Society.
As a consequence, the majority of women with heart failure
may be treated too late or not at all, he says. "Heart
failure in women looks radically different from heart
failure in men. As a result it is often under-diagnosed."
Heart failure in most men is usually due to systolic
dysfunction. The heart is weakened and markedly dilated and
cannot adequately pump the blood through the body. It is
often described as "floppy" heart.
On the other hand, female patients with heart failure are
usually older but have diastolic dysfunction. This is
characterized by a small and "stiff" heart, rather than
dilated ("floppy") heart. The heart`s ability to relax
between beats is impaired. The symptoms are often not well
recognized and, in the presence of a small heart, physicians
often will miss the diagnosis of heart failure.
"It is now thought that more than half of the patients who
come to emergency rooms with episodes of acute heart failure
today actually have diastolic heart failure," says Dr. Liu,
Heart & Stroke/Polo Chair of Medicine and Physiology at the
University of Toronto and Scientific Director of the
Institute of Circulatory and Respiratory Health at the
Canadian Institutes of Health Research.
"We can expect a seismic change over the next decade as
women with heart failure begin to swell the patient
population," he warns.
"Because diastolic heart failure is not always preceded by
symptoms such as angina or a heart attack, many women are
surprised to hear they have a heart problem at all," says
Dr. Liu, The only way of diagnosing the beginnings of
diastolic heart failure is by clinical suspicion, an
echocardiogram, and a blood test to check the levels of
markers such as brain natriuretic peptide (BNP).
Diastolic heart failure is often preceded by common risk
factors such as hypertension and diabetes. "We have learned
recently that diastolic heart failure is the result of heart
cell stiffness and poor blood flow in the small vessels of
the heart. This is akin to encasing the heart in strands of
cement, while starving it of blood supply through shrinkage
of the blood vessels," says Dr. Liu. "There is also new
evidence to suggest that defective protein clearance is
contributing to the disease, akin to abnormal protein
deposition seen in Alzheimer's disease."
"Because of this gender difference, cardiologists used to
think these may be separate forms of heart disease. We know
better now," says Dr. Liu. However, because the definitive
treatment for diastolic heart failure is yet to evolve,
effective prevention may turn out to be the best treatment,
he says.
"The problem with diastolic heart failure, especially in
women, is that it has a lifetime prevalence of 20 per cent -
or roughly double the likelihood of breast cancer," says Dr.
Jonathan Howlett, spokesperson for the Canadian
Cardiovascular Society and chair of the CCS national heart
failure guidelines initiative. "Because of a lack of studies
outlining effective therapies for this common condition, we
are left with few guidelines to follow and resort to
treating the conditions that give rise to it. New research
in this area is among our most important needs."
Dr. Liu cautions that because high blood pressure, diabetes,
and shortage of blood flow are the contributing risk factors
for diastolic heart failure, these risks must be addressed
proactively. Therefore, it is most important that the
patient's blood pressure is checked annually, and if
elevated, must be treated effectively to target. The blood
sugar should also be checked, and diabetes can often indeed
be prevented by regular exercise, maintenance of ideal
weight, and following a healthy diet with plenty of fruits
and vegetables.
"We are concerned that women at risk of heart failure may
miss out on the most effective opportunity to prevent it
altogether - lifestyle change and early detection," says Dr.
Liu. "Therefore, we must call to action the increased
awareness of heart failure in our women patients and the
effective prevention of heart failure by addressing risk
factors up front."
"Dr. Liu's data underscores the challenges that the medical
profession and women often face in the diagnosis and
treatment of heart disease," says Heart and Stroke
Foundation spokesperson Dr. Beth Abramson. "Evaluation and
awareness of any gender difference is the key to reversing
this trend.
"While advances in research, prevention, and treatment
continue, medical professionals need to make sure with
ongoing assessment that there is no disparity in care
regarding gender differences. This will help to ensure
that all Canadians have access to optimal cardiovascular
care."
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Statements and conclusions of study authors are solely those
of the study authors and do not necessarily reflect
Foundation or CCS policy or position. The Heart and Stroke
Foundation of Canada and the Canadian Cardiovascular Society
make no representation or warranty as to their accuracy or
reliability.
The Heart and Stroke Foundation (heartandstroke.ca), a
volunteer-based health charity, leads in eliminating heart
disease and stroke and reducing their impact through the
advancement of research and its application, the promotion
of healthy living, and advocacy.
The Canadian Cardiovascular Society (ccs.ca) is the national
voice for cardiovascular physicians and scientists. Its
mission is to promote cardiovascular health and care through
knowledge translation, professional development, and
leadership in health policy.
