We performed a retrospective analysis of 79 patients with cerebral sinus venous thrombosis, who were treated with a fixed regimen of dose-adjusted intravenous heparin, to determine predictors of a fatal course. The parameters investigated were the state of consciousness and the presence of intracranial haemorrhage (ICH) at the start of heparin treatment, involvement of the internal venous system, mean delay from initial symptom to stupor or coma and from initial symptom to hospital admission, focal neurological deficits, mean intracranial circulation time (ICT) on conventional angiography, and age and sex distribution. Mortality rate was 10% in this series (8/79). There was a strong link between the outcome and the level of vigilance: 53% of the patients with stupor or coma at the start of the heparin therapy died (8/15), whereas all of the 64 patients with no more than mildly impaired vigilance survived (p < 0.00001). Furthermore, mean age and mean ICT were significantly higher in the group of patients who died. There was a statistical trend (p = 0.056) for ICH to be more frequent in cases with fatal outcome, but there was reason to assume that ICH represented an epiphenomenon of a severe course rather than an independent predictor. Other investigated parameters were not linked with a fatal outcome. Copyright (C) 2003 S. KargerAG, Basel.