Acute coronary syndrome: guidelines for anti-platelets and anti-coagulants

Warfarin, aspirin, clopidogrel, prasugrel, ticagrelor, DOACs enoxaparin and fondaparinux

Direct oral anticoagulants (DOACs) - Apixaban, Edoxaban, Rivaroxaban and Dabigatran

*If Aspirin 300mg has been given by SAS (Scottish Ambulance Service) do not repeat

If a patient is admitted with ACS and is already taking warfarin and INR is therapeutic:

• Do not give enoxaparin or fondaparinux
• Give admission dose of aspirin 300mg* and clopidogrel 300mg if troponin positive
• Give admission dose of aspirin 300mg* but not clopidogrel if troponin negative
• Early senior decision as to whether to continue aspirin and/or add clopidogrel

If a patient is admitted with ACS and is already taking warfarin and INR is sub-therapeutic and there is a definite ongoing indication for warfarin:

• Start Enoxaparin treatment dose according to patient's weight as per local guidelines
• Give admission dose of aspirin 300mg* and clopidogrel 300mg if troponin positive
• Give admission dose of aspirin 300mg* but not clopidogrel if troponin negative
• Early senior decision as to whether to continue aspirin and/or add clopidogrel

If a patient is admitted with ACS and is already taking warfarin and INR is supra-therapeutic more than 4:

• Senior review before additional antiplatelet therapy

If a patient is admitted with ACS and warfarin needs to be stopped temporarily (e.g. if patient needs angiography):

• If need for ongoing anticoagulation, start treatment dose enoxaparin.
• If patient undergoing angiography with view to PCI, start aspirin 75mg once daily give Clopidogrel 300mg stat loading, then 75mg once daily thereafter - in addition to enoxaparin.
• If not for angiography/PCI, senior decision whether to give antiplatelet treatment

If patient is already on anti-platelet therapy and needs to start warfarin:

• Start warfarin and treatment dose enoxaparin until INR therapeutic
• Senior review whether need for concomitant anti-platelet therapy – indication and duration for concomitant therapy must be documented on warfarin prescription form and in the patient’s notes.

If patient is admitted with ACS and is taking a DOAC:

• Do not give enoxaparin or fondaparinux
• Give admission dose of aspirin 300mg* and clopidogrel 300mg if troponin positive
• Give admission dose of aspirin 300mg* but not clopidogrel if troponin negative
• Ensure senior review before next dose of DOAC If patient is already on anti-platelet therapy and needs to start a DOAC:
• Start DOAC (apixaban preferable as per East region formulary).
• Senior medic to review whether there is need for concomitant anti-platelet therapy-indication for concomitant therapy must be documented clearly in patient’s notes.

• All patients on dual antiplatelets/anticoagulant therapy should be considered for PPI (Lansoprazole is preferred).
• Durations of concomitant therapy (anti-coagulation and anti-platelets) should be clearly documented in patient notes.
• If in doubt about combination therapy ask cardiologist or senior medic
• Review need for all these agents regularly