NICE guidance - warfarin (vitamin K antagonists) post myocardial infarction (MI)

Last reviewed 01/2018

NICE have issued guidance as to the use of vitamin K antagonists post myocardial infarction (1):

  • high-intensity warfarin (INR >3) should not be considered as an alternative to aspirin in first-line treatment, for patients who have had an MI
  • for patients who have had an MI and are unable to tolerate either aspirin or clopidogrel
    • treatment with moderate-intensity warfarin (INR 2-3) should be considered for up to 4 years, and possibly longer
  • for patients who have had an acute MI, are intolerant to clopidogrel and have a low risk of bleeding, treatment with aspirin and moderate-intensity warfarin (INR 2-3) combined should be considered
  • for patients already being treated for another indication (mechanical valve, recurrent deep vein thrombosis, atrial fibrillation, left ventricular thrombus), warfarin should be continued
    • if a patient is being treated with moderate-intensity warfarin (INR 2-3) and who is at low risk of bleeding, then the addition of aspirin should be considered
  • combination treatment with warfarin and clopidogrel is not routinely recommended


  1. NICE (May 2007). Secondary prevention in primary and secondary care for patients following a myocardial infarction