Anticoagulation for cerebral sinus thrombosis

Treatment of cerebral sinus thrombosis with anticoagulants has been controversial. Anticoagulants may prevent new venous infarcts, neurologic deterioration, and pulmonary embolism but may also promote haemorrhages.

To review the available evidence regarding the effectiveness and safety of anticoagulant therapy in patients with confirmed cerebral sinus thrombosis.

We searched the Cochrane Stroke Group Trials Register (last searched 18 March 2002). We also searched MEDLINE (1966-Oct 2001), EMBASE (1980-Feb 2002) and the Cochrane Controlled Trials Register (Cochrane Library, 2002 Issue 1) and contacted authors to identify additional published and unpublished studies.

Unconfounded randomised controlled trials in which anticoagulant therapy was compared with placebo or open control in patients with cerebral sinus thrombosis (confirmed by intra-arterial contrast or magnetic resonance angiography).

Two reviewers independently extracted outcomes for each of the two treatment groups (anticoagulant treatment and control). The outcome data for each patient are analysed in the treatment group to which the patient was originally allocated ('intention to treat' analysis). A weighted estimate of the treatment effects across trials (relative risk, absolute risk reduction) is calculated using the Cochrane statistical software.

Two small trials involving 79 patients fulfilled the inclusion criteria. One trial (20 patients) examined the efficacy of intravenous, adjusted dose unfractionated heparin. The other trial (59 patients) examined high dose, body weight adjusted, subcutaneous, low-molecular weight heparin (Nadroparin). Anticoagulant therapy was associated with a pooled relative risk of death of 0.33 (95 % CI 0.08 to 1.21) and of death or dependency of 0.46 (95 % CI 0.16 to 1.31). No new symptomatic intracerebral haemorrhages were observed. One major gastro-intestinal haemorrhage occurred after anticoagulant treatment. Two control patients (placebo) had a diagnosis of probable pulmonary embolism (one fatal).

Based upon the limited evidence available, anticoagulant treatment for cerebral sinus thrombosis appeared to be safe and was associated with a potentially important reduction in the risk of death or dependency which did not reach statistical significance.