RESUMO
The significance of low-molecular-weight heparins [LMWHs] in the management of acute stroke remains controversial. One hundred patients with acute ischemic stroke in evolution were enrolled [with symptoms of stroke within eight hours of randomization]. Patients were randomized to receive Unfractionated Heparin [UFH] at a dose 5000 IU by IV bolus, followed by a continuous IV infusion; or to Enoxaparin [ENOX] at a dose of 0.5 mg per kilogram body weight. Therapy was continued for 10 days. National Institutes of Health Stroke Scale [NIHSS] and Computed Tomography [CT] scan were performed in all patients at the time of admission, and after 48 hours of randomization. It was found that, the mean baseline National Institutes of Health Stroke Score [NIHSS] was 9.14 +/- 0.62 among patients randomized to UFH, vs. 7.86 +/- 0.54 among patients randomized to ENOX [p = 0.2]. At discharge, the mean NIHSS showed a statistically significant difference in favor of the ENOX group [7.9 +/- 0.82 for the UFH arm versus 4.96 +/- 0.54 for the ENOX arm; p = 0.002]. The mean NIHSS after therapy in patients who demonstrated neurological improvement was 5.6 +/- 0.46 in the UFH arm, as opposed to 3.65 +/- 0.39 in the ENOX arm [p = 0.001]. A deterioration in the clinical neurological condition [progressive stroke symptoms] inspite of treatment with anticoagulant therapy was seen in 20% [n = 10] of the patients in the UFH treatment arm and no patients in the ENOX treatment arm showed this condition [p = 0.005]. No statistically significant differences were observed for pulmonary embolism, deep venous thrombosis, recurrent strokes, or death. It was concluded that, Enoxaparin [+ aspirin] was superior to UFH [+ aspirin] in reducing adverse neurological disability after acute ischemic stroke in evolution. This superiority was not associated with reductions in mortality, and could be explained by blunting of von Willebrand factor release by Enoxaparin