Abstract & Commentary
Source: Ferro JM, et al, for the ISCVT Investigators. Prognosis of cerebral vein and dural sinus thrombosis. Stroke. 2004;35:664-670.
In contrast to arterial thrombo-embolic ischemic stroke, cerebral venous sinus thrombosis (CVST) is unique in its clinical presentation and treatment algorithm. CVST often presents with headache as a result of increased intracranial pressure (ICP) and frequently produces a hemorrhagic component with seizures. CVST is also benign in comparison with ischemic stroke. As reported by Ferro and associates on behalf of the multicenter international ISCVT study, venous stroke, typically treated with heparin, has a good outcome in the vast majority of cases.
Ferro et al report on 624 cases of CVST. Patients were analyzed for the presence of thrombophilia and for risk factors such as malignancy, pregnancy, and oral contraceptive use. Many patients (43.6%) had more than one risk factor. Diagnoses were made by MR venography in the majority of patients, with many undergoing formal angiography as well. Lumbar puncture was done in 224 patients, with 83.5% showing an elevated opening pressure (> 180 mm H20). There was evidence of an infarct on CT or MRI in 46.5% of patients, with findings of a hemorrhage in 39.3%. Either intravenous or low-molecular-weight heparin was given in 83.3% of patients. Local endovascular thrombolysis was performed in only 2.1% of patients. Anti-epileptic drugs were used in 44.4%.
Outcome analysis was based on a follow-up of 16 months (median time). On average, patients were kept on anti-coagulation for 7.7 months. The majority of patients (57.1%) had a Modified Rankin Scale of zero (no symptoms or signs) at final follow-up, with 22% having minor residual symptoms. Small numbers of patients were left with severe impairments (2.2%), and the total mortality was 8.3%. Roughly half of the deaths were not related to the CVST but rather to an underlying condition, such as cancer. Multivariate predictors of death or disability were age older than 37 years, male sex, coma, hemorrhage on admission CT scan, thrombosis of the deep cerebral venous system, central nervous system infection, and cancer.
Not surprisingly, patients with a syndrome of isolated intracranial hypertension, without focal neurological signs, had the best outcomes. There was a trend in favor of those patients treated with therapeutic doses of anticoagulation in the acute phase, but this did not reach statistical significance. In cases of CVST related to pregnancy (n = 77), 8 women went on to have uncomplicated births.
This large study confirms that heparin should be the standard of care for patients with CVST. Treated appropriately, the majority of patients have an excellent outcome, often producing no permanent neurologic deficits. The presence of clinical features such as coma or deep-vein involvement predict more serious outcomes. While such high-risk findings may suggest a need for more aggressive management, such as endovascular thrombolysis, data from randomized studies would be needed to validate their efficacy. Finally, identification of risk factors (which may often be multiple) is important in identifying those patients at risk for CVST recurrence. — Alan Z. Segal, MD, Assistant Professor, Department of Neurology, Weill-Cornell Medical College, Attending Neurologist, New York Presbyterian Hospital and Assistant Editor of Neurology Alert.