Beta
Blockers Save Lives in Long Run
Reduce
deaths years after a heart attack
The
lifesaving effects of beta blocker drugs for many people who have heart
attacks or major heart rhythm disturbances last a lot longer than has
been thought, a recent study finds.
It
is long been known that beta blockers, so called because they reduce
the work of heart muscle by blocking activity of stress-related neurotransmitters
such as epinephrine, lower the death rate in the hours and days after
a heart attack. Now a report in Circulation: Journal of the
American Heart Association shows that lives are saved even
years later, not only for heart attack patients but also for those whose
heart rhythm is irregular enough to raise the risk of sudden, fatal
cardiac arrest.
"What
we have added is that they have ongoing benefits remote from an immediate
myocardial infarction [heart attack]," says Dr. Kristin E. Ellison,
assistant professor of medicine at Brown Medical School and lead author
of the journal report. "The median time of enrollment in our study was
30-something months."
Over
that period, heart attack patients who were given beta blockers consistently
did better than those who were not. The death rate for beta blocker
patients was 16 percent lower after two years and 34 percent lower after
five years, compared to patients who did not get the drugs.
Study
Reinforces Current Recommendations For Beta-Blocker Usage
The
finding will not cause any dramatic change in treatment, but it
adds powerful reinforcement to current recommendations for use of beta
blockers in a specific patient group, Ellison says. "Hopefully, everyone
is prescribing beta blockers to this patient population," she says.
"There are no harmful effects and clear benefits, so the drugs should
not be withheld from this patient population."
All
of the more than 2,000 patients in the study had suffered heart attacks
that substantially reduced the heart's ability to pump blood. Some were
also found to have abnormally fast, irregular heartbeats, or tachycardia,
which can cause sudden death.
The
primary purpose of the study was to see whether careful monitoring of
the heart's activity could save lives, but the researchers also compared
survival rates of patients who did or did not get beta blockers and
came up with the successful results.
Beta
Blockers Help to Prevent Fatal Arrhythmias
One
reason why beta blockers save lives is that they prevent fatal arrhythmias,
Ellison says, but that is not the complete explanation. "It is probably
a combination of all of the effects of beta blockers, since the study
found not just a specific anti-arrhythmia benefit but a total mortality
benefits," she says.
"This
is adding to the body of knowledge we already have," says Dr. Robert
Bonow, professor of medicine at Northwestern University and president
of the American Heart Association. "These drugs are
very helpful in patients who have a damaged heart or weak heart function."
Bonow
says he would be inclined to prescribe a beta blocker for any heart
attack patient. But the evidence of the new study shows that the effect
is strongest in cases when the heart is damaged enough to reduce its
pumping ability by 40 percent, he says.
Always
consult your physician for more information.
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