Non-ST-elevation myocardial infarction

Overview 
Theory 
Diagnosis 
Management 
Follow up 
Resources 

Your Organisational Guidance

ebpracticenet urges you to prioritise the following organisational guidance:

Behandeling acuut coronair syndroom in een urgente situatie (in afwachting van hospitalisatie)Published by: Werkgroep Ontwikkeling Richtlijnen Eerste Lijn (Worel)Last published: 2022La prise en charge du syndrome coronarien aigu (SCA) en situation d'urgence (en attente d'hospilatisation)Published by: Groupe de Travail Développement de recommmandations de première ligneLast published: 2022

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups: see disclaimer

ACUTE

very high-risk or high-risk features (suspected or confirmed NSTEMI)

1st line – refer for invasive coronary angiography ± revascularisation

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1st line –

refer for invasive coronary angiography ± revascularisation

Get urgent input from a senior colleague or cardiology if the patient is clinically unstable or has any very high-risk features (as outlined below) to arrange immediate invasive coronary angiography (with the intent to perform revascularisation).[5] Do not wait for the results of troponin testing.[5] This includes any patient with:[72][73]

Ongoing or recurrent pain despite treatment
Haemodynamic instability (low blood pressure or shock) or cardiogenic shock; see Shock
Recurrent dynamic ECG changes
Acute left ventricular failure, presumed secondary to ongoing myocardial ischaemia; see Acute heart failure
A life-threatening arrhythmia (ventricular tachycardia or ventricular fibrillation) or cardiac arrest after presentation; see Sustained ventricular tachycardias[5]
Mechanical complications such as new-onset mitral regurgitation.[5]

An inpatient invasive management strategy is recommended for most patients presenting with non-ST-elevation acute coronary syndrome (NSTE-ACS); the timing of this is guided by an early risk assessment, which divides patients into very high risk, high risk, or non-high risk.[5] High-risk patients should have invasive coronary angiography (ICA) within 24 hours.[5]

Offer ICA within 24 hours of admission to hospital if the patient has at least one 'high-risk' criteria:

A confirmed diagnosis of NSTEMI based on current recommended European Society of Cardiology (ESC) high-sensitivity cardiac troponin (hs-cTn) algorithms
Dynamic ST-segment or T-wave changes
Transient ST-segment elevation
A GRACE risk score >140.

Choice of revascularisation strategy (either percutaneous coronary intervention [PCI] or coronary artery bypass graft [CABG]) should be made based on an informed discussion with the patient and, if needed, with the multidisciplinary team.[72]

Plus – aspirin

Back

Plus –

aspirin

Treatment recommended for ALL patients in selected patient group

Give all patients with suspected NSTEMI a single loading dose of aspirin as soon as possible, unless they have significant bleeding risk or hypersensitivity to aspirin.[5][72][74]

In practice, assess the patient’s risk of bleeding using the HAS-BLED score.[1] [ HAS-BLED Bleeding Risk Score Opens in new window ] Ensure the patient has intravenous access and discuss them with a senior colleague if they have significant bleeding risk or are actively bleeding.
Check your local protocol or discuss the patient with a senior colleague if they have hypersensitivity to aspirin.
- In practice, monotherapy with a P2Y₁₂ inhibitor may be used (see below).[1]

Primary options

aspirin: 300 mg orally (chewed or dispersed in water) as a loading dose, followed by 75-100 mg once daily thereafter

Consider – oxygen

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Consider –

oxygen

Additional treatment recommended for SOME patients in selected patient group

Do not give oxygen routinely. Offer oxygen only if the patient has oxygen saturations <90% or respiratory distress.[5]

Evidence: Oxygen therapy in patients with acute myocardial infarction

There is no evidence from randomised controlled trials (RCTs) to support the routine use of inhaled oxygen in people with acute myocardial infarction (MI) without hypoxia, but guidelines vary on their specific recommendations.

There are different recommendations in guidelines on the thresholds for starting oxygen therapy. Guidelines also vary on recommended upper limits for oxygen saturation once oxygen has been started.

The 2023 European Society of Cardiology guidelines for the management of acute coronary syndromes (ACS) recommends that routine oxygen is not given if the arterial oxygen saturation is ≥90%.[5] The evidence underpinning this recommendation, the AVOID study, is indirect evidence from people with STEMI. However, the study authors concluded there was some evidence that oxygen therapy given to people with “uncomplicated acute MI” may increase myocardial injury.[114] This guideline recommends oxygen therapy for hypoxic patients with an oxygen saturation <90% (based on limited evidence).
A 2018 BMJ Rapid Recommendation also recommends that oxygen therapy is not initiated in patients with acute MI if the oxygen saturation is ≥90%.[115] This is based on the findings from a large systematic review and meta-analysis that liberal oxygen therapy was associated with higher mortality than conservative oxygen therapy in adults with acute illness (see below).[116]
The National Institute of Health and Care Excellence (NICE) guideline on chest pain of recent onset, last updated in 2016, recommends that supplemental oxygen is not routinely offered to patients with suspected acute coronary syndrome.[74] It recommends oxygen therapy if the patient has an oxygen saturation <94% and is not at risk of hypercapnic respiratory failure, aiming for a saturation of 94% to 98%. For patients with COPD who are at risk of hypercapnic respiratory failure, it recommends a target oxygen saturation of 88% to 92%, until blood gas analysis is available.
The 2016 Scottish Intercollegiate Guideline Network (SIGN) guideline on ACS does not include a specific recommendation on the use of oxygen but does refer to a Cochrane review stating that it found no conclusive evidence to support the routine use of inhaled oxygen in patients with acute MI.[117][118]

There is a lack of evidence to support the routine use of oxygen in patients with acute MI when there is no hypoxia, although oxygen therapy has commonly been used as part of the initial management of patients with acute MI.

A 2018 systematic review and meta-analysis of seven RCTs (including the AVOID study and the large multicentre DETO2X-AMI trial) and a total of 7702 patients with acute MI without hypoxaemia found that routine supplemental oxygen did not reduce:[119]
- Mortality
- Arrhythmias
- Heart failure
- Recurrent ischaemic events.
The systematic review excluded one RCT (n=72) as it included all people with non-ST-segment elevation ACS without hypoxia, not just NSTEMI.[120]
- They found that oxygen therapy made no difference to any outcomes including frequency of angina or need for opioid analgesia during the second 24 hours of hospitalisation, or length of hospital stay.

Regarding the upper limit for target oxygen saturation once oxygen has been started, evidence from a large systematic review and meta-analysis on oxygen use in acutely unwell adults not at risk of hypercapnic respiratory failure (including those with MI) supports a 96% upper limit for target oxygen saturation.

One large systematic review (published in 2018) of 25 RCTs and over 16,000 patients, including one meta-analysis, found that in adults with acute illness (including MI, but also including sepsis, critical illness, stroke, trauma, cardiac arrest, and emergency surgery), liberal oxygen therapy (broadly equivalent to a target saturation >96%) is associated with higher mortality than conservative oxygen therapy (broadly equivalent to a target saturation ≤96%).[116]
In-hospital mortality was 11 per 1000 higher with liberal oxygen therapy versus conservative oxygen therapy (95% CI 2 to 22 per 1000 more). Mortality at 30 days was also higher with liberal oxygen (risk ratio [RR] 1.14, 95% confidence interval [CI] 1.01 to 1.29). Studies that were limited to people with chronic respiratory illness or psychiatric illness, on extracorporeal life support, receiving hyperbaric oxygen therapy, or having elective surgery were all excluded from the review.[116]

A lower target oxygen saturation of 88% to 92% is appropriate if the patient is at risk of hypercapnic respiratory failure.[74][121]

Consider – glyceryl trinitrate

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Consider –

glyceryl trinitrate

Additional treatment recommended for SOME patients in selected patient group

Offer pain relief with glyceryl trinitrate as soon as possible.[74]

Give up to three doses of translingual/sublingual glyceryl trinitrate before considering an intravenous glyceryl trinitrate infusion.[1]
Monitor blood pressure carefully when giving glyceryl trinitrate because it can cause hypotension.[122]

Practical tip

Do not give intravenous glyceryl trinitrate if there is:[5]

Hypotension
Marked bradycardia or tachycardia
Known severe aortic stenosis
Right ventricular infarction
Use of a phosphodiesterase-5 inhibitor (e.g., avanafil, sildenafil, tadalafil, vardenafil) for erectile dysfunction within the last 48 hours.

Primary options

glyceryl trinitrate translingual: 400-800 micrograms administered under the tongue via aerosol spray as a single dose, may repeat every 5 minutes if required, maximum 3 doses; 300-600 micrograms sublingually as a single dose, may repeat every 5 minutes if required, maximum 3 doses

Secondary options

glyceryl trinitrate: 10 micrograms/minute intravenous infusion initially, adjust dose according to response, maximum 400 micrograms/minute

Consider – morphine

Consider – anti-emetic

Plus – P2Y12 inhibitor

Back

Plus –

P2Y12 inhibitor

Treatment recommended for ALL patients in selected patient group

Seek advice from cardiology about use of a P2Y₁₂ inhibitor to determine the type, dose, and timing.

The UK National Institute for Health and Care Excellence (NICE) recommends the following:[72]

Prasugrel if the patient is undergoing percutaneous coronary intervention (PCI), the coronary anatomy has been defined, and the patient has no separate indication for ongoing anticoagulation. In practice this is usually prescribed by the cardiologist at the time of invasive coronary angiography (ICA).
- For patients aged 75 years and over, the bleeding risk of using prasugrel needs to be weighed up against its effectiveness.
Ticagrelor if the patient is undergoing PCI and has no separate indication for ongoing anticoagulation OR if the patient is not undergoing PCI and does not have a high bleeding risk.
Clopidogrel if the patient is undergoing PCI and has a separate indication for ongoing anticoagulation OR if the patient is not undergoing PCI and has a high bleeding risk.
- NICE also recommends aspirin alone as an alternative if the patient is not undergoing PCI and has a high bleeding risk.

The European Society of Cardiology does not recommend routine pretreatment with a P2Y₁₂ inhibitor if the coronary anatomy is unknown and ICA is planned within 24 hours.[5][113] However, in our expert’s opinion, a P2Y₁₂ inhibitor may be given to a clinically unstable patient before ICA if the coronary anatomy is known; if the patient deteriorates they may be unable to swallow tablets.

Primary options

prasugrel: <75 years of age and body weight <60 kg: 60 mg orally as a loading dose, followed by 5 mg once daily thereafter; <75 years of age and body weight ≥60 kg: 60 mg orally as a loading dose, followed by 10 mg once daily thereafter; ≥75 years of age: 60 mg orally as a loading dose, followed by 5 mg once daily thereafter

ticagrelor: 180 mg orally as a loading dose, followed by 90 mg twice daily thereafter

clopidogrel: 300 mg orally as a loading dose, followed by 75 mg once daily thereafter

Plus – anticoagulation

Back

Plus –

anticoagulation

Treatment recommended for ALL patients in selected patient group

Discuss the patient with the cardiology team before starting anticoagulation; take into account factors such as bleeding risk, contraindications, likelihood and timing of invasive coronary angiography (ICA), and degree of renal impairment when making decisions about type and dose of anticoagulation.[1][5][72]

Unfractionated heparin is used if the patient is going for immediate ICA but is generally given in the cardiac catheter laboratory by a cardiologist.[72]

In practice, always assess the patient’s bleeding risk using HAS-BLED before giving an anticoagulant. [ HAS-BLED Bleeding Risk Score Opens in new window ] Carefully consider the choice and dose of anticoagulant for patients with a high risk of bleeding associated with:[72]

Advancing age
Known bleeding complications
Renal impairment
Low body weight.

Primary options

heparin: 75 units/kg (or 5000 units) intravenously as a loading dose, followed by 18 units/kg/hour intravenous infusion; adjust dose according to aPTT

no high-risk features (suspected or confirmed NSTEMI)

1st line – aspirin

Back

1st line –

aspirin

Give all patients with suspected NSTEMI a single loading dose of aspirin as soon as possible, unless they have significant bleeding risk or hypersensitivity to aspirin.[5][72][74]

In practice, assess the patient’s risk of bleeding using the HAS-BLED score.[1] [ HAS-BLED Bleeding Risk Score Opens in new window ] Ensure the patient has intravenous access and discuss them with a senior colleague if they have significant bleeding risk or are actively bleeding.
Check your local protocol or discuss the patient with a senior colleague if they have hypersensitivity to aspirin.
- In practice, monotherapy with a P2Y₁₂ inhibitor may be used (see below).[1]

Primary options

aspirin: 300 mg orally (chewed or dispersed in water) as a loading dose, followed by 75-100 mg once daily thereafter

Consider – referral for invasive coronary angiography ± revascularisation

Back

Consider –

referral for invasive coronary angiography ± revascularisation

Additional treatment recommended for SOME patients in selected patient group

For patients who do not have very high-risk or high-risk criteria, the strategy can be tailored based on the degree of clinical suspicion. Note that the European Society of Cardiology (ESC) recommends that all patients presenting with confirmed NSTEMI should have an invasive strategy, unless there is a contraindication to angiography, such as significant comorbidities or terminal cancer.[5] The UK National Institute of Health and Care Excellence (NICE), however, recommends that conservative management can be considered for patients with a low risk of adverse cardiovascular events (<3.0% 6-month mortality).[72]

Be aware that some younger people who score as 'low' risk may still be at high risk of adverse cardiovascular events and may benefit from early invasive coronary angiography (ICA).[72]

If the patient is having conservative management but subsequently develops symptoms of ischaemia, or if ischaemia is demonstrated by further testing (e.g., stress testing), ICA should be offered.[72]

Consider – oxygen

Back

Consider –

oxygen

Additional treatment recommended for SOME patients in selected patient group

Do not give oxygen routinely. Offer oxygen only if the patient has oxygen saturations <90% or respiratory distress.[5]

Evidence: Oxygen therapy in patients with acute myocardial infarction

The 2023 European Society of Cardiology guidelines for the management of acute coronary syndromes (ACS) recommends that routine oxygen is not given if the arterial oxygen saturation is ≥90%.[5] The evidence underpinning this recommendation, the AVOID study, is indirect evidence from people with STEMI. However, the study authors concluded there was some evidence that oxygen therapy given to people with “uncomplicated acute MI” may increase myocardial injury.[114] This guideline recommends oxygen therapy for hypoxic patients with an oxygen saturation <90% (based on limited evidence).
A 2018 BMJ Rapid Recommendation also recommends that oxygen therapy is not initiated in patients with acute MI if the oxygen saturation is ≥90%.[115] This is based on the findings from a large systematic review and meta-analysis that liberal oxygen therapy was associated with higher mortality than conservative oxygen therapy in adults with acute illness (see below).[116]
The National Institute of Health and Care Excellence (NICE) guideline on chest pain of recent onset, last updated in 2016, recommends that supplemental oxygen is not routinely offered to patients with suspected acute coronary syndrome.[74] It recommends oxygen therapy if the patient has an oxygen saturation <94% and is not at risk of hypercapnic respiratory failure, aiming for a saturation of 94% to 98%. For patients with COPD who are at risk of hypercapnic respiratory failure, it recommends a target oxygen saturation of 88% to 92%, until blood gas analysis is available.
The 2016 Scottish Intercollegiate Guideline Network (SIGN) guideline on ACS does not include a specific recommendation on the use of oxygen but does refer to a Cochrane review stating that it found no conclusive evidence to support the routine use of inhaled oxygen in patients with acute MI.[117][118]

A 2018 systematic review and meta-analysis of seven RCTs (including the AVOID study and the large multicentre DETO2X-AMI trial) and a total of 7702 patients with acute MI without hypoxaemia found that routine supplemental oxygen did not reduce:[119]
- Mortality
- Arrhythmias
- Heart failure
- Recurrent ischaemic events.
The systematic review excluded one RCT (n=72) as it included all people with non-ST-segment elevation ACS without hypoxia, not just NSTEMI.[120]
- They found that oxygen therapy made no difference to any outcomes including frequency of angina or need for opioid analgesia during the second 24 hours of hospitalisation, or length of hospital stay.

One large systematic review (published in 2018) of 25 RCTs and over 16,000 patients, including one meta-analysis, found that in adults with acute illness (including MI, but also including sepsis, critical illness, stroke, trauma, cardiac arrest, and emergency surgery), liberal oxygen therapy (broadly equivalent to a target saturation >96%) is associated with higher mortality than conservative oxygen therapy (broadly equivalent to a target saturation ≤96%).[116]
In-hospital mortality was 11 per 1000 higher with liberal oxygen therapy versus conservative oxygen therapy (95% CI 2 to 22 per 1000 more). Mortality at 30 days was also higher with liberal oxygen (RR 1.14, 95% CI 1.01 to 1.29). Studies that were limited to people with chronic respiratory illness or psychiatric illness, on extracorporeal life support, receiving hyperbaric oxygen therapy, or having elective surgery were all excluded from the review.[116]

A lower target oxygen saturation of 88% to 92% is appropriate if the patient is at risk of hypercapnic respiratory failure.[74][121]

Consider – glyceryl trinitrate

Back

Consider –

glyceryl trinitrate

Additional treatment recommended for SOME patients in selected patient group

Offer pain relief with glyceryl trinitrate as soon as possible.[74]

Give up to three doses of translingual/sublingual glyceryl trinitrate before considering an intravenous glyceryl trinitrate infusion.[1]
Monitor blood pressure carefully when giving glyceryl trinitrate because it can cause hypotension.[122]

Practical tip

Do not give intravenous glyceryl trinitrate if there is:[5]

Hypotension
Marked bradycardia or tachycardia
Known severe aortic stenosis
Right ventricular infarction
Use of a phosphodiesterase-5 inhibitor (e.g., avanafil, sildenafil, tadalafil, vardenafil) for erectile dysfunction within the last 48 hours.

Primary options

Secondary options

glyceryl trinitrate: 10 micrograms/minute intravenous infusion initially, adjust dose according to response, maximum 400 micrograms/minute

Consider – morphine

Consider – anti-emetic

Plus – P2Y12 inhibitor

Back

Plus –

P2Y12 inhibitor

Treatment recommended for ALL patients in selected patient group

Give a P2Y₁₂ inhibitor in addition to aspirin as part of dual antiplatelet therapy once NSTEMI is confirmed.[72] Check your local protocol when deciding which P2Y₁₂inhibitor to use and the timing of this.

The UK National Institute for Health and Care Excellence (NICE) recommends the following:[72]

Prasugrel if the patient is undergoing percutaneous coronary intervention (PCI), the coronary anatomy has been defined, and the patient has no separate indication for ongoing anticoagulation. In practice this is usually prescribed by the cardiologist at the time of invasive coronary angiography (ICA).
- For patients aged 75 years and over, the bleeding risk of using prasugrel needs to be weighed up against its effectiveness.
Ticagrelor if the patient is undergoing PCI and has no separate indication for ongoing anticoagulation OR if the patient is not undergoing PCI and does not have a high bleeding risk.
Clopidogrel if the patient is undergoing PCI and has a separate indication for ongoing anticoagulation OR if the patient is not undergoing PCI and has a high bleeding risk.
- NICE also recommends aspirin alone as an alternative if the patient is not undergoing PCI and has a high bleeding risk.
The European Society of Cardiology does not recommend routine pretreatment with a P2Y₁₂ inhibitor if the coronary anatomy is unknown and ICA is planned within 24 hours.[5][113]

Primary options

ticagrelor: 180 mg orally as a loading dose, followed by 90 mg twice daily thereafter

clopidogrel: 300 mg orally as a loading dose, followed by 75 mg once daily thereafter

Plus – anticoagulation

Back

Plus –

anticoagulation

Treatment recommended for ALL patients in selected patient group

Give fondaparinux if the patient does not have a high bleeding risk unless they are undergoing immediate ICA.[72]
Consider unfractionated heparin as an alternative to fondaparinux if the patient has significant renal impairment (creatinine >265 micromol/L [>3 mg/dL]).[72] Unfractionated heparin is also used if the patient is going for immediate ICA but is generally given in the cardiac catheter laboratory by a cardiologist.[72]
- Adjust the dose according to monitoring of clotting function.[72]
Bivalirudin may be an alternative to heparin, though it is not routinely used in the UK.[124]

Advancing age
Known bleeding complications
Renal impairment
Low body weight

Primary options

fondaparinux: 2.5 mg subcutaneously once daily for up to 8 days (or hospital discharge if sooner)

Secondary options

heparin: 75 units/kg (or 5000 units) intravenously as a loading dose, followed by 18 units/kg/hour intravenous infusion; adjust dose according to aPTT

Tertiary options

bivalirudin: 100 micrograms/kg intravenously for 1 dose, followed by 500 micrograms/kg for 1 dose, then 1.75 mg/kg/hour intravenous infusion for the duration of the procedure, reduce to 250 micrograms/kg/hour for 4-12 hours as necessary following percutaneous coronary intervention

Consider – beta-blocker

Plus – ACE inhibitor or angiotensin-II receptor antagonist

Back

Plus –

ACE inhibitor or angiotensin-II receptor antagonist

Treatment recommended for ALL patients in selected patient group

Start an ACE inhibitor as soon as a patient with NSTEMI is haemodynamically stable.[72]

Give an angiotensin-II receptor antagonist instead of an ACE inhibitor to patients who are intolerant to ACE inhibitors.[72]
Measure renal function, serum electrolytes, and blood pressure before starting an ACE inhibitor or angiotensin-II receptor antagonist.[72] In practice, if the patient has abnormal renal function or blood pressure, start with a low dose and titrate this carefully with close monitoring.

Primary options

enalapril: 2.5 mg orally once daily initially, increase gradually according to response, usual dose 10-20 mg twice daily, maximum 40 mg/day

ramipril: 2.5 mg orally twice daily for 3 days, increase gradually according to response, maximum 10 mg/day

lisinopril: 2.5 to 5 mg orally once daily initially, increase gradually according to response, maximum 10 mg/day

Secondary options

valsartan: 20 mg orally twice daily initially, increase gradually according to response, maximum 320 mg/day

losartan: 12.5 mg orally once daily initially, increase gradually according to response, maximum 150 mg/day

candesartan: 4 mg orally once daily initially, increase gradually according to response, maximum 32 mg/day

Plus – manage hyperglycaemia

ONGOING

post-NSTEMI

1st line – continue dual antiplatelet therapy

Back

1st line –

continue dual antiplatelet therapy

Ensure all patients are given dual antiplatelet therapy with aspirin and a P2Y₁₂ inhibitor (while taking into account any contraindications; seek specialist advice if the patient has a separate indication for anticoagulation).[5][72]

Check your local protocol or discuss the patient with a senior colleague if the patient has hypersensitivity to aspirin. In practice, monotherapy with a P2Y₁₂ inhibitor may be used; the UK National Institute of Health and Care Excellence recommends clopidogrel.[72]

The European Society of Cardiology recommends 12 months of dual antiplatelet therapy as the default strategy, although alternative regimens can be considered in certain circumstances depending on bleeding and ischaemic risks:[5]

Single antiplatelet therapy (preferably with a P2Y₁₂ inhibitor) for patients who are event-free after 3 to 6 months of dual antiplatelet therapy and who are not high ischaemic risk
Aspirin or P2Y₁₂ inhibitor monotherapy after 1 month of dual antiplatelet therapy in patients with high bleeding risk
Abbreviated dual antiplatelet therapy strategies and de-escalation of dual antiplatelet therapy can be considered in patients at high risk of bleeding.[5]

Practical tip

Evidence on the selection and duration of antiplatelet therapy following coronary revascularisation is evolving rapidly, with studies showing potential benefits from different strategies.[125][126]

In the UK, you should check the patient’s clinical report for an individualised plan written by the interventional cardiology team. This should specify what antiplatelet therapy is advised for long-term management, based on current evidence, individual patient factors, and the specific interventions undertaken for each patient.

Primary options

aspirin: 75-100 mg once daily thereafter

-- AND --

prasugrel: <75 years of age and body weight <60 kg: 5 mg orally once daily; <75 years of age and body weight ≥60 kg: 10 mg orally once daily; ≥75 years of age: 5 mg orally once daily

ticagrelor: 90 mg orally twice daily

clopidogrel: 75 mg orally once daily

Secondary options

clopidogrel: 75 mg orally once daily

Plus – start or continue beta-blocker

Plus – start or continue ACE inhibitor or angiotensin-II receptor antagonist

Back

Plus –

start or continue ACE inhibitor or angiotensin-II receptor antagonist

Treatment recommended for ALL patients in selected patient group

Ensure all patients are given an ACE inhibitor (while taking into account any contraindications).[72]

Start this as soon as the patient is haemodynamically stable and continue it indefinitely.[72]
In patients with heart failure, long-term use of ramipril improves survival.[127]
Offer an angiotensin-II receptor antagonist as an alternative if the patient is intolerant to an ACE inhibitor.[72]
Measure renal function, serum electrolytes, and blood pressure before starting an ACE inhibitor or angiotensin-II receptor antagonist.[72] In practice, if the patient has abnormal renal function or blood pressure, start with a low dose and titrate this carefully with close monitoring.

Primary options

enalapril: 2.5 mg orally once daily initially, increase gradually according to response, usual dose 10-20 mg twice daily, maximum 40 mg/day

ramipril: 2.5 mg orally twice daily for 3 days, increase gradually according to response, maximum 10 mg/day

lisinopril: 2.5 to 5 mg orally once daily initially, increase gradually according to response, maximum 10 mg/day

Secondary options

valsartan: 20 mg orally twice daily initially, increase gradually according to response, maximum 320 mg/day

losartan: 12.5 mg orally once daily initially, increase gradually according to response, maximum 150 mg/day

candesartan: 4 mg orally once daily initially, increase gradually according to response, maximum 32 mg/day

Plus – statin

Consider – ezetimibe

Consider – proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor

Back

Consider –

proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitor

Additional treatment recommended for SOME patients in selected patient group

A PCSK9 inhibitor monoclonal antibody may be added to statin and ezetimibe therapy if LDL-cholesterol targets are not achieved despite maximal statin and ezetimibe therapy.[5][46][65][134][135] Treatment can be started during ACS admission or at outpatient follow-up 4-6 weeks later.

Primary options

evolocumab: 140 mg subcutaneously every 2 weeks; or 420 mg subcutaneously once monthly

alirocumab: 75-150 mg subcutaneously every 2 weeks; or 300 mg subcutaneously every 4 weeks

Consider – aldosterone antagonist

Consider – sodium-glucose cotransporter-2 (SGLT2) inhibitor

Plus – cardiac rehabilitation

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Non-ST-elevation myocardial infarction

Treatment algorithm

Your Organisational Guidance

very high-risk or high-risk features (suspected or confirmed NSTEMI)

refer for invasive coronary angiography ± revascularisation

aspirin

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

oxygen

Evidence: Oxygen therapy in patients with acute myocardial infarction

glyceryl trinitrate

Practical tip

Primary options

Secondary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Secondary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

Secondary options

morphine

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

anti-emetic

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

P2Y12 inhibitor

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

anticoagulation

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

no high-risk features (suspected or confirmed NSTEMI)

aspirin

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

referral for invasive coronary angiography ± revascularisation

oxygen

Evidence: Oxygen therapy in patients with acute myocardial infarction

glyceryl trinitrate

Practical tip

Primary options

Secondary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Secondary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

Secondary options

morphine

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

anti-emetic

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

P2Y12 inhibitor