Dual antiplatelet therapy for NSTEACS

For patients with confirmed NSTEACS, give a P2Y12 inhibitor (clopidogrel, prasugrel, ticagrelor) with aspirin.

The P2Y12 inhibitor can either be administered at the time of diagnosis (ie as pretreatment before invasive management), after invasive coronary angiography (ie once the coronary anatomy is known), or as part of medical management (when coronary angiography is not planned). The timing and type of P2Y12 inhibitor should be determined in consultation with the cardiology team, with consideration of bleeding risk, the likely time to invasive coronary angiography and the coronary anatomy.

Evidence suggests that there is no benefit (and possibly an increased risk of bleeding) with routine pretreatment if invasive coronary angiography is likely to occur within 72 hoursDawson, 2021Dworeck, 2020Montalescot, 2013Schupke, 2019. However, in practice, pretreatment is commonly used unless invasive management will occur on the day of presentation or there is a high clinical suspicion that urgent coronary artery bypass grafting is needed.

For patients with low-risk unstable angina (see Overview of management of non-ST elevation acute coronary syndrome (NSTEACS)), a P2Y12 inhibitor may be indicated, depending on the findings of further investigations. See Low-risk unstable angina.

If dual antiplatelet therapy for NSTEACS is appropriate, use:

aspirin 300 mg orally, chewed or dissolved before swallowing, for the first dose, then 100 to 150 mg orally, daily1 aspirin aspirin aspirin

PLUS ONE OF THE FOLLOWING

1prasugrel 60 mg orally, for the first dose, then 10 mg daily23 prasugrel prasugrel prasugrel

OR

1ticagrelor 180 mg orally, for the first dose, then 90 mg twice daily ticagrelor ticagrelor ticagrelor

OR

2clopidogrel 300 to 600 mg orally, for the first dose, then 75 mg daily. clopidogrel clopidogrel clopidogrel

The preferred P2Y12 inhibitors are ticagrelor and prasugrel; these have more rapid onset of action, less variable platelet inhibition and better clinical outcomes than clopidogrelCollet, 2021Wallentin, 2009Wiviott, 2007.

Clopidogrel is used if ticagrelor and prasugrel are not available or are contraindicated4, including if the patient:

  • has a separate indication for oral anticoagulation
  • has a high or very high bleeding risk (eg a PRECISE-DAPT score of more than 25 or a HAS-BLED score of more than 3)
  • has had prior intracranial haemorrhage or stroke, or recent gastrointestinal bleeding or anaemia, or has a coagulopathy
  • has liver failure, or severe kidney failure (estimated glomerular filtration rate [eGFR] less than 15 mL/min or requiring dialysis)
  • is of extreme old age or frail.
1 If the patient has already received a 300 mg dose of aspirin, do not repeat the initial 300 mg dose.Return
2 Do not use prasugrel for patients who weigh less than 60 kg, are aged 75 years or older, or who have had a previous stroke or transient ischaemic attack. Only give prasugrel once coronary anatomy has been defined and PCI is intended.Return
3 At the time of writing, prasugrel is not available on the Pharmaceutical Benefits Scheme (PBS). See the PBS website for current information.Return
4 Do not use prasugrel for patients who weigh less than 60 kg, are aged 75 years or older, or who have had a previous stroke or transient ischaemic attack. Only give prasugrel once coronary anatomy has been defined and PCI is intended. Do not use ticagrelor for patients who have second- or third-degree atrioventricular (AV) block.Return