Stroke patients with mild symptoms
may still need clot-dissolving drug
MGH study finds lack of treatment
in eligible patients raises risk of death and disability
BOSTON - October 6, 2005 - Although use of the clot-dissolving
drug tissue plasminogen activator (tPA) has revolutionized the treatment
of acute stroke patients, many of those who could receive the drug
do not because their initial symptoms appear mild or improve soon
after they arrive at the hospital. Now a study from Massachusetts
General Hospital (MGH) confirms previous observations that eligible
patients who do not receive tPA face a significant risk of disability.
The report will appear in the November issue of Stoke and
is receiving early online release.
"Our primary finding was that about 30 percent of those patients
judged 'too good to treat' either died or were discharged to a rehabilitation
facility," says Eric Smith, MD, FRCPC, of MGH Neurology, the
study's lead author. "Unfortunately we were not able to find
any features that could predict which of the untreated patients
would have problems."
When a stroke is caused by a blocked blood vessel, tPA can safely
dissolve the clot if given within three hours of symptom onset,
sometimes completely reversing the effects of the stroke. Many patients
do not arrive at a hospital soon enough to receive the drug, but
even when they do, physicians must weigh the small but significant
risk that tPA treatment could cause a brain hemorrhage, a potentially
devastating complication. Because of this risk, patients with less
severe symptoms may not receive tPA in the hopes that they will
get better on their own. An observation from an earlier study suggested
that many of those patients would not do well and led to the current
The research team reviewed records on more than 400 patients with
ischemic (clot-related) stroke that came to the MGH Emergency Department
from 2002 to 2004. Of 128 patients who arrived within the three-hour
safe treatment window, 71 did not receive tPA. More than half the
untreated patients had been considered "too good to treat,"
primarily because their symptoms were stable and mild or improved
rapidly. Out of those 41 patients, two died during their hospitalization
and nine were discharged to a rehabilitation facility because of
continuing neurological problems.
Smith explains that rapid symptom improvement seen early in the
course of a stroke could reflect the affected area of the brain
"borrowing" blood from nearby areas. But if the initial
blockage affects the primary blood supply and is not removed, symptoms
may eventually worsen.
"Right now we can only recommend that physicians be a little
more cautious in deciding against tPA treatment," he adds.
"We can suggest that more attention be paid to patients' ability
to walk - something that often is not evaluated - since gait disturbance
was a reason why several could not go home. But we really need to
find ways to predict who will do poorly without tPA, and for that
we'll need larger trials involving several institutions." Smith
is an instructor in Neurology at Harvard Medical School.
The senior author of the Stroke report is Lee Schwamm, MD,
associate director of the MGH
Acute Stroke Service. Other co-authors are Abdul Abdullah, MD,
and Walter Koroshetz, MD, of the MGH; Iva Petrovska, MD, University
of California at Los Angeles, and Eric Rosenthal, MD, Beth Israel-Deaconess
Medical Center. The study was supported by grants from the National
Institutes of Health and the Centers for Disease Control and Prevention.
Massachusetts General Hospital, established in 1811, is the original
and largest teaching hospital of Harvard Medical School. The MGH
conducts the largest hospital-based research program in the United
States, with an annual research budget of more than $450 million
and major research centers in AIDS, cardiovascular research, cancer,
cutaneous biology, medical imaging, neurodegenerative disorders,
transplantation biology and photomedicine. In 1994, MGH and Brigham
and Women's Hospital joined to form Partners HealthCare System,
an integrated health care delivery system comprising the two academic
medical centers, specialty and community hospitals, a network of
physician groups, and nonacute and home health services.
Media Contact: Sue
McGreevey, MGH Public Affairs
Physician Referral Service: 1-800-388-4644
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