Context Tissue-type plasminogen activator (tPA) is the only therapy for acute
ischemic stroke approved by the Food and Drug Administration.
Objective To assess the safety profile and to document clinical outcomes and adverse
events in patients treated with intravenous tPA for acute stroke in clinical
practice.
Design and Setting Prospective, multicenter study of consecutive patients enrolled between
February 1997 and December 1998 at 57 medical centers in the United States
(24 academic and 33 community).
Intervention Intravenous tPA (recombinant alteplase).
Patients Three hundred eighty-nine patients with a mean age of 69 years (range,
28-100 years); 55% were men.
Main Outcome Measures Time intervals between stroke symptom onset, hospital arrival, and treatment
with tPA; pretreatment computed tomographic scan results, intracerebral hemorrhage,
and major systemic bleeding. The modified Rankin Scale score was used to assess
clinical outcomes at 30 days.
Results Median time from stroke onset to treatment was 2 hours 44 minutes, and
the median baseline National Institutes of Health Stroke Scale score was 13.
The 30-day mortality rate was 13%. At 30 days after treatment, 35% of patients
had very favorable outcomes (modified Rankin score, 0-1) and 43% were functionally
independent (modified Rankin score, 0-2). Thirteen patients (3.3%) experienced
symptomatic intracerebral hemorrhage, including 7 who died. Twenty-eight patients
(8.2%) had asymptomatic intracerebral hemorrhage within 3 days of treatment
with tPA. Protocol violations were reported for 127 patients (32.6%), and
included treatment with tPA more than 3 hours after symptom onset in 13.4%,
treatment with anticoagulants within 24 hours of tPA administration in 9.3%,
and tPA administration despite systolic blood pressure exceeding 185 mm Hg
in 6.7%. A multivariate analysis found predictors of favorable outcome to
be a less severe baseline National Institutes of Health Stroke Scale score,
absence of specific abnormalities (effacement or hypodensity of >33% of the
middle cerebral artery territory or a hyperdense middle cerebral artery) on
the baseline computed tomographic scan, an age of 85 years or younger, and
a lower mean arterial pressure at baseline.
Conclusions This study, conducted at multiple institutions throughout the United
States, suggests that favorable clinical outcomes and low rates of symptomatic
intracerebral hemorrhage can be achieved using tPA for stroke treatment.