Protecting the Heart:
Cardiovascular risks decline, but vigilence is warranted
In the pursuit of malignant tumor cells, normal tissues and
organs get caught in the crossfire
of cancer treatment. This has been
especialy true of the heart.
In earlier decades, radiation to the chest could
carry deadly cardiovascular risks. Newer treatment
methods, however, are putting the odds
in patients' favor. We talked with Lori Pierce,
M.D., University of Michigan professor of radiation
oncology, about the latest developments.
Dr. Lori Pierce discusses the potential
impact of radiation therapy on the heart.
Technological advances now allow doctors to minimize cardiovascular risks of
radiation therapy.
View Dr. Pierce's
clinical trial.
Q. Who is at risk for radiationassociated
heart disease?
A. Technically, anyone who's getting radiation
to the chest where the heart could be
affected. The most likely person who could
potentially be at risk is someone who has
cancer in the left breast, depending on whether
lymph nodes or internal mammary nodes need
to be treated.
Q. What types of heart problems
might patients experience after
treatment?
A. Arrhythmias, or erratic heartbeats, and
scarring that affects the heart's ability to pump
blood can occur. Pericarditis -- or inflammation
of the lining around the heart -- is sometimes
seen in patients who've been treated for Hodgkin's
disease. Probably the area we're most
concerned about is coronary artery disease,
which has been found in patients who were
treated with older techniques used up through
the 1980s.
Q. Have newer treatment methods
reduced the risk for cardiac side
effects?
A. Current radiation techniques have dramatically
reduced the risk of heart-related toxicity,
but we are always very mindful about the risk,
particularly in left-sided breast cancer. Multiple
recent studies show that there aren't big differences
in incidence of cardiovascular disease
among patients who were treated for left-sided
breast cancer vs. those who were treated for
right-sided breast cancer. It strongly suggests
that the techniques we're using are dramatically
less toxic to the heart than older methods.
Q. How do new techniques
minimize risk?
A. Computerized three-dimensional planning
allows us to see exactly where the heart
is sitting and set up radiation fields so we can
minimize the amount of radiation delivered
to the heart. In this day and age, many of our
patients are receiving other treatments, such
as Adriamycin, that can damage the heart.
The goal is to minimize cardiac exposure to
radiation to prevent further injury. We are
continuing to study the best ways to do that.
Q. How are you studying this?
A. I'm working on a study that is looking at
two methods of radiation delivery to determine
whether we can further reduce radiation exposure
to the heart. The study, which involves
people with left-sided breast cancer, will record
baseline heart and lung tests before treatment
and then compare them with follow-up tests
a year after treatment. However, even if
patients show that their heart has been exposed
to radiation, it does not necessarily mean
symptoms will develop down the road. Usually,
it takes about 10 years for cardiac symptoms
to appear.
Q. Can people who may be at risk
for cardiovascular side effects
do anything to lower their risk?
A. Talk to your primary care physician about
your cardiac health. Find out from your oncologist
whether any of your treatments carry
increased risk for cardiovascular problems and
share this information with your regular doctor.
If you have hypertension, make sure
to treat it. Discuss risks that may be associated
with a family history of heart disease. Exercise,
eat a heart-healthy diet and think in terms
of overall health maintenance.
return to the top of the page
