heart monitor may increase risks
Illinois (AP) -- A heart-monitoring procedure used more than a million
times a year during major operations appears to serve no benefit
and may actually raise the risk of heart attacks, a study found.
Right heart catheterization -- in which a thin, flexible tube is
inserted into a neck vein and guided into the right side of the
heart -- is used during major, non-cardiac operations such as hip
replacements and gall bladder removal on patients with a history
of heart trouble.
has been used on patients for 30 years to monitor the heart for
everything from fluid pressure to oxygen content.
researchers at Brigham and Women's Hospital in Boston found no benefit
to the procedure and said the risk of heart attacks and other cardiac
problems was three times greater among patients who had it than
among those who did not.
procedure should be re-evaluated, the researchers said. Their study,
which appeared in Wednesday's Journal of the American Medical Association,
supports earlier findings.
is unclear whether the procedure itself causes problems or whether
information provided by the monitoring leads to overly aggressive
corrective treatments that may harm patients, said Dr. Thomas Lee,
an associate professor at Harvard Medical School who led the study.
old-time clinicians feel that younger doctors get hypnotized by
the numbers from high-tech monitoring devices, and overreact and
treat minor fluctuations in numbers from the catheter," Lee
is also possible that patients who underwent catheterization simply
were sicker than the study's data indicated, he said.
National Heart, Lung and Blood Institute is now conducting two studies
on the use of right heart catheterization.
don't think it's dangerous, but the study shows we have some real
work to do to say which patients can really benefit from it,"
said there are no other safer procedures that monitor heart function
to the same extent. Without a catheter, doctors simply keep track
of blood pressure and heart rate, as well as oxygen saturation.
study involved 4,059 patients -- 221 had the monitoring procedure
and 3,838 did not -- 50 and older who underwent major elective non-cardiac
operations at Brigham and Women's Hospital between 1989 and 1994.
came up with 215 matched pairs of patients who did and did not undergo
the procedure but had similar medical risks. Those who underwent
the procedure had a threefold greater risk of cardiac problems.
The findings appear to support a 1996 study that found patients
who underwent right heart catheterization had a 21 percent greater
risk of death in the succeeding 30 days. That study prompted calls
for more research and a government moratorium on the procedure.
The Food and Drug Administration did not issue a moratorium but
did recommend clinical trials.
an editorial accompanying Lee's study, Dr. James Dalen of the University
of Arizona Health Sciences Center, editor of the Archives of Internal
Medicine, said that given the risks and expense of right heart catheterization,
it should not be used routinely.
Ann Thompson, president of the Society of Critical Care Medicine,
said the study could have missed crucial differences between patients
in the matched pairs.
just don't believe that the problem, with rare exceptions, is with
the catheter," said Thompson, a professor of anesthesiology,
critical care medicine and pediatrics at the University of Pittsburgh.
She said it is possible that the fault lies with the surgeons using