Anticoagulation in the prevention of stroke

• NICE state (1):
  • anticoagulation treatment should not be used routinely for the treatment of acute stroke
  • people with disabling ischaemic stroke who are in atrial fibrillation should be treated with aspirin 300 mg for the first 2 weeks before considering anticoagulation treatment
  • in people with prosthetic valves who have disabling cerebral infarction and who are at significant risk of haemorrhagic transformation, anticoagulation treatment should be stopped for 1 week and aspirin 300 mg substituted
  • people with ischaemic stroke and symptomatic proximal deep vein thrombosis or pulmonary embolism should receive anticoagulation treatment in preference to treatment with aspirin unless there are other contraindications to anticoagulation
  • people with haemorrhagic stroke and symptomatic deep vein thrombosis or pulmonary embolism should have treatment to prevent the development of further pulmonary emboli using either anticoagulation or a caval filter

In patients with non-cardioembolic stroke, warfarin was not more effective than aspirin and increased the rates of all cause death, major haemorrhage, and myocardial infarction or death (2

A systematic review found that anticoagulants increase intracerebral bleeding and do not reduce death or disability in acute cardioembolic stroke (3)

Reversal of anticoagulation treatment in people with haemorrhagic stroke

• return clotting levels to normal as soon as possible in people with a primary intracerebral haemorrhage who were receiving warfarin before their stroke (and have elevated international normalised ratio). Do this by reversing the effects of the warfarin using a combination of prothrombin complex concentrate and intravenous vitamin K

Reference:

• (1) NICE (May 2019). The diagnosis and acute management of stroke and transient ischaemic attacks
• (2) Chimowitz MI et al. Comparison of warfarin and aspirin for symptomatic intracranial arterial stenosis. NEJM 2005; 352:1305-16.
• (3) Paciaroni M et al. Efficacy and safety of anticoagulant treatment in acute cardioembolic stroke: a meta-analysis of randomized controlled trials. Stroke. 2007 Feb;38(2):423-30.