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Chest pain

Asked to see

12-lead ECG straight away. Do not exclude ACS on a normal ECG.

Act now

  1. 1

    12-lead ECG and continuous monitoring. Compare with old ECGs.

  2. 2

    Suspected ACS: aspirin 300 mg loading dose unless clearly allergic.

  3. 3

    Oxygen only if SpO₂ <94% (88–92% if hypercapnic risk).

  4. 4

    Pain relief: GTN, IV opioid if needed.

Assess

  • Character, onset, radiation, associated symptoms, risk factors, previous ECGs.
  • Life-threatening differentials: ACS, aortic dissection, PE, tension pneumothorax, oesophageal rupture, tamponade.

Investigations

  • Troponin per local high-sensitivity protocol (timed repeat).
  • FBC, U&E, glucose, lipids, CXR. CTPA or CT aortogram if PE or dissection suspected.

Manage

  • STEMI: immediate reperfusion pathway — call the cardiology/PCI team.
  • NSTEMI/unstable angina: fondaparinux unless high bleeding risk or immediate angiography planned; risk-score and discuss DAPT with cardiology.
  • Unequal arm BPs, tearing pain to the back, or new aortic regurgitation: suspect dissection — do not give antithrombotics until excluded.

Escalate when

  • ST elevation, haemodynamic instability, arrhythmia, ongoing pain despite treatment, or suspected dissection: senior and cardiology immediately.

Doses and prescribing

Aspirin

300 mg orally (chewed or dispersed).

GTN

400 micrograms sublingual spray; avoid if systolic BP <90 or recent PDE5 inhibitor.

Fondaparinux

2.5 mg SC daily for NSTEMI (check renal function).

Check the BNF and your local formulary before prescribing.

Written to current guidance (NICE CG95, NG185) · sources checked 14 Nov 2026. We watch NICE for updates weekly.

Sources (4)

Reviewed by Aboodee Alhasso, MPharm MRCPharm IP on 14 Nov 2026

Calculators for this

For healthcare professionals, as an aid to clinical judgement — not a substitute for it. Follow your local policy and ask a senior when in doubt.