Article

Pulmonary embolism after acute ischemic stroke (AIS) is associated
with a high in-hospital mortality. The benefit from pharmacological prophylaxis
for venous thromboembolism (VTE) is uncertain probably due to doubts about the
optimal agent and dose. We evaluated the benefit/risk ratio of different
anticoagulant regimens in the prevention of VTE in patients with AIS. METHODS:
The MEDLINE, EMBASE, and Cochrane Library databases were searched up to January
2005. Randomized controlled trials (RCT) comparing early administration of either
low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) with control
were included. Endpoints were objectively diagnosed deep-vein thrombosis (DVT),
pulmonary embolism, intracranial hemorrhage (ICH), and extracranial hemorrhage
(ECH). Low-dose UFH was arbitrarily defined as < or =15,000 IU/day, low-dose LMWH
as < or =6000 IU/day or weight-adjusted dose of < or =86 IU/kg/day. RESULTS:
Sixteen trials involving 23,043 patients with AIS met the inclusion criteria. The
number of events was small and different doses of anticoagulant treatment were
used. Compared to control, high-dose UFH was associated with a reduction in
pulmonary embolism (OR=0.49, 95% confidence interval
(CI)=0.29-0.83), but also
with an increased risk of ICH (OR=3.86, 95% CI=2.41-6.19) and ECH (OR=4.74, 95%
CI=2.88-7.78). Low-dose UFH decreased the thrombosis risk (OR=0.17, 95%
CI=0.11-0.26), but had no influence on pulmonary embolism (OR=0.83, 95%
CI=0.53-1.31); the risk of ICH or ECH was not statistically significant increased
(OR=1.67, 95% CI=0.97-2.87 for ICH; and OR=1.58, 95% CI=0.89-2.81 for ECH,
respectively). High-dose LMWH decreased both DVT (OR=0.07, 95% CI=0.02-0.29) and
pulmonary embolism (0.44, 95% CI=0.18-1.11), but this benefit was offset by an
increased risk for ICH (OR=2.01, 95% CI=1.02-3.96) and ECH (OR=1.78, 95%
CI=0.99-3.17). Low-dose LMWH reduced the incidence of both DVT (OR=0.34, 95%
CI=0.19-0.59) and pulmonary embolism (OR=0.36, 95% CI=0.15-0.87), without an
increased risk of ICH (OR=1.39, 95% CI=0.53-3.67) or ECH
(OR=1.44, 95%
CI=0.13-16). For low-dose LMWH, the numbers needed to treat were 7 and 38 for DVT
and pulmonary embolism, respectively. CONCLUSIONS: Indirect comparison of low and
high doses of UFH and LMWH suggests that low-dose LMWH have the best benefit/risk
ratio in patients with acute ischemic stroke by decreasing the risk of both DVT
and pulmonary embolism, without a clear increase in ICH or ECH.

Langue : ANGLAIS

Tiré à part : OUI