What is the initial treatment for cerebral sinus venous thrombosis?

Initial Treatment for Cerebral Sinus Venous Thrombosis

Immediate anticoagulation with either intravenous unfractionated heparin or subcutaneous low-molecular-weight heparin should be started as soon as the diagnosis is confirmed, and the presence of intracranial hemorrhage is explicitly NOT a contraindication to anticoagulation. 1, 2

Diagnostic Confirmation Before Treatment

• Confirm the diagnosis with MRI plus MR venography as the preferred imaging modality 1, 3
• Use CT venography if MRI is unavailable or contraindicated 1, 3
• Consider catheter angiography only if initial imaging is negative but clinical suspicion remains high 1, 3

Immediate Anticoagulation Protocol

Low-molecular-weight heparin (LMWH) is the preferred initial anticoagulant due to superior efficacy compared to unfractionated heparin 2:

• Enoxaparin: 1.0 mg/kg subcutaneously twice daily OR 1.5 mg/kg once daily 2
• Dalteparin: 200 U/kg subcutaneously once daily 2

Unfractionated heparin (UFH) is an appropriate alternative when LMWH is contraindicated, unavailable, in severe renal failure (creatinine clearance <30 mL/min), or when thrombolytic therapy may be needed 2:

• Initial bolus: 5000 IU intravenously 2
• Continuous infusion: approximately 30,000 IU over 24 hours 2
• Adjust to maintain aPTT at 1.5-2.5 times baseline 2

Critical Management Principle: Anticoagulation Despite Hemorrhage

The presence of intracerebral hemorrhage related to CVST is NOT a contraindication to anticoagulation 1, 2, 3. This is a high-strength recommendation based on the understanding that hemorrhagic transformation in CVST results from venous congestion, and the risk of thrombus propagation outweighs bleeding concerns 2. Historical data from randomized trials showed no new symptomatic intracerebral hemorrhages with anticoagulation, and retrospective analysis demonstrated lower mortality (15% vs 69%) in hemorrhagic CVST patients treated with heparin compared to those who were not 4.

Acute Care Setting and Monitoring

• Admit all patients to a stroke unit or neurocritical care setting for close monitoring 1, 3
• Monitor neurological status every 2-4 hours for signs of deterioration including worsening consciousness, new focal deficits, or seizures 2, 3
• Treat seizures aggressively with antiepileptic medications if they occur 3

Transition to Oral Anticoagulation

Begin oral anticoagulants early while continuing parenteral anticoagulation 2:

• Continue parenteral anticoagulation for a minimum of 5 days AND until INR ≥2.0 for at least 24 hours 2
• Target INR range of 2.0-3.0 (target 2.5) for vitamin K antagonists 2
• In patients with mechanical heart valves, antiphospholipid syndrome, or severe renal impairment, warfarin is preferred over direct oral anticoagulants 2

Duration of Anticoagulation

The minimum duration is 3 months, with extension based on underlying etiology 1, 2:

• Provoked CVST (transient risk factors like pregnancy or infection): 3-6 months 1, 2
• Idiopathic CVST or mild thrombophilia: 6-12 months 3
• Severe thrombophilia (antiphospholipid syndrome, two or more prothrombotic abnormalities) or recurrent thrombosis: Indefinite (lifelong) anticoagulation 1, 2
• Cancer-associated CVST: Continue anticoagulation as long as anti-cancer treatment is given 2

Escalation for Treatment Failure

Consider mechanical thrombectomy or endovascular thrombolysis in patients with absolute contraindications to anticoagulation or failure of initial therapeutic anticoagulation 2

Decompressive hemicraniectomy may be lifesaving in patients with severe mass effect, large intracerebral hemorrhage, or impending herniation causing progressive neurological deterioration 2, 3

Follow-Up Imaging

• Perform follow-up CT venography or MR venography at 3-6 months after diagnosis to assess recanalization in stable patients 2, 3
• Earlier imaging (every 1-3 months) is indicated if persistent or evolving symptoms occur despite medical treatment 3

Investigation of Underlying Causes

Investigate prothrombotic conditions as this directly affects anticoagulation duration 1, 3. Recommended testing includes factor V Leiden, prothrombin G20210A, antiphospholipid antibodies, and other thrombophilia screening 3.