Chest pain
ECG within 10 minutes, then think of the six killers: heart attack, aortic dissection, PE, tension pneumothorax, tamponade and oesophageal rupture. "Gas" is a diagnosis of exclusion.
A 38-year-old man has had central chest heaviness for 40 minutes, spreading to his left arm, with sweating. He smokes and has diabetes. He says it is "gas" and wants an injection for the pain.
What do you do in the first 10 minutes?
- ECG within 10 minutesCompare with any old ECG. Repeat it if the pain changes or continues.
- ObservationsPulse, BP in both arms, SpO₂, RR, temperature.
- STEMI?Activate the STEMI pathway now: primary PCI or thrombolysis. See Acute coronary syndrome.
- Think of the six killersHeart attack, aortic dissection, PE, tension pneumothorax, tamponade, oesophageal rupture.
- Aspirin if ACS is likely300 mg chewed, unless dissection is suspected or there is a true allergy.
- BloodsTroponin (and repeat per protocol), CBC, urea, creatinine, electrolytes, sugar, lipids.
- Chest X-rayPneumothorax, wide mediastinum, consolidation, free air.
- Treat the painGTN if BP allows, then IV morphine if needed. No IM injections.
- ST elevation or new left bundle branch block
- Pain with low BP, new murmur or BP difference between arms
- Tearing pain to the back
- Low SpO₂ or one-sided absent breath sounds
- Ongoing pain despite treatment
- Rising troponin
- STEMI with subtle changes (posterior, high lateral)
- Aortic dissection
- Pulmonary embolism
- Tension pneumothorax
- Cardiac tamponade
- Oesophageal rupture
| ECG | Within 10 minutes of arrival |
| Aspirin | 300 mg chewed if ACS likely and no sign of dissection |
| GTN | Sublingual, only if systolic BP above 90 and no sildenafil or tadalafil in the last 24–48 hours |
| Oxygen | Only if SpO₂ below 94% |
| Troponin | At arrival and repeated per your lab's protocol (often 1–3 hours) |
Check every dose against a current drug reference and your hospital protocol.
On this page
The six killers
Most chest pain in the emergency department is not dangerous. Your job is to find the patients whose pain is. Go through these six every time, even when the patient is sure it is "gas" or "acidity".
- Heavy, pressing, central
- Spreads to arm, jaw, neck
- Sweating, nausea, breathless
- ECG changes, rising troponin
- Sudden, tearing, to the back
- BP difference between arms
- Pulse deficit, new murmur, stroke signs
- Wide mediastinum
- Sudden breathlessness, pleuritic pain
- Fast pulse, low SpO₂
- Calf swelling, recent surgery or travel
- Sudden pain and breathlessness
- Absent breath sounds one side
- Low BP, distended neck veins
- Low BP, distended neck veins, quiet heart sounds
- Recent MI, cancer, renal failure, TB, trauma
- Pain after heavy vomiting
- Unwell, fever, air under the skin of the neck
History
- Character: pressure, heaviness, tightness (cardiac); sharp and worse on breathing (pleura, pericardium); tearing to the back (dissection); burning after food (reflux, but only once the others are excluded).
- Onset: sudden and maximal at the start suggests dissection, PE or pneumothorax.
- Radiation: arm, jaw, neck (cardiac); between the shoulder blades (dissection).
- With: sweating, vomiting, breathlessness, fainting.
- Risk factors: smoking, diabetes, high BP, high cholesterol, family history of early heart disease. Heart attacks happen at younger ages in South Asians: a 35-year-old smoker with diabetes is not "too young".
- Women, diabetics and the elderly often have atypical symptoms: breathlessness, tiredness, epigastric pain, no pain at all.
- Medicines: sildenafil or tadalafil (no GTN), cocaine, recent long travel or surgery (PE).
Examination
- Pulse, BP in both arms (a difference of more than 20 mmHg suggests dissection), SpO₂, RR, temperature.
- Heart sounds, new murmur (aortic regurgitation in dissection, mitral regurgitation after MI), pericardial rub.
- Neck veins, chest air entry, calf swelling.
- Tenderness of the chest wall does not exclude a heart attack.
Investigations
| Test | Why | What to look for |
|---|---|---|
| ECG | Within 10 minutes, repeat if pain continues | ST elevation, ST depression, T wave inversion, new LBBB, posterior changes |
| Troponin | Heart muscle damage | Use your lab's high-sensitivity protocol: a rise between samples matters |
| Chest X-ray | Other causes | Pneumothorax, wide mediastinum, consolidation, free gas under the diaphragm |
| CBC, urea, creatinine, electrolytes, sugar | Baseline, before contrast and anticoagulants | Anaemia, kidney function, potassium |
| D-dimer | Only if PE probability is low by Wells score | A negative result helps exclude PE |
| CT aortogram | Suspected dissection | Do not wait: call your senior |
| Echo | Tamponade, wall motion, valves | Pericardial effusion |
Aspirin, oxygen and pain relief
Do not give intramuscular diclofenac or other painkiller injections for chest pain. They mask the pain, add bleeding risk if the patient later needs thrombolysis or anticoagulation, and NSAIDs harm the heart and kidneys.
- Oxygen only if SpO₂ is below 94%. Routine oxygen in a patient with normal saturations does not help.
- "GI cocktails" (antacids) do not prove the pain is from the stomach. Cardiac pain can also ease by chance.
Risk after the first troponin
The HEART score (History, ECG, Age, Risk factors, Troponin) helps your senior decide who can go home after a negative troponin protocol.
| Score | Risk | Usual plan |
|---|---|---|
| 0–3 | Low | May be discharged after negative troponins with outpatient follow-up |
| 4–6 | Moderate | Admit or observe, cardiology review |
| 7–10 | High | Admit, treat as ACS, early invasive strategy |
Common causes that are not killers
| Cause | Clues |
|---|---|
| Musculoskeletal | Sharp, reproduced by pressing or moving, after strain |
| Reflux or gastritis | Burning, related to food or lying flat (only after excluding the killers) |
| Pericarditis | Sharp, better sitting forward, rub, widespread saddle-shaped ST elevation |
| Pneumonia or pleurisy | Fever, cough, pleuritic pain, crackles |
| Shingles | Burning band of pain, rash appears days later |
| Anxiety | Diagnosis of exclusion only |
Common mistakes
- Labelling chest pain as "gas" or "acidity" before an ECG and troponin.
- One normal ECG and sending the patient home while the pain continues.
- Thinking a young South Asian man is too young for a heart attack.
- Giving aspirin and heparin to a patient with tearing pain to the back.
- Giving IM diclofenac for chest pain.
- Missing a posterior MI (tall R and ST depression in V1–V3): do posterior leads V7–V9.
Frequently asked questions
What should be done first for chest pain in the emergency department?
An ECG within 10 minutes of arrival, observations including BP in both arms, and assessment for the six life-threatening causes.
When should aspirin be given for chest pain?
300 mg chewed when acute coronary syndrome is likely, unless aortic dissection is suspected, there is a true allergy, or active bleeding.
What are the signs of aortic dissection?
Sudden tearing or ripping pain going to the back, BP difference of more than 20 mmHg between the arms, pulse deficit, new aortic regurgitation murmur, stroke symptoms, and a wide mediastinum on X-ray.
Can a normal ECG rule out a heart attack?
No. The first ECG can be normal. Repeat it if the pain continues and use serial troponins.
Test yourself
Exam-style questions on this guide, from our two question banks. Choose an answer to see why each option is right or wrong.
1. A 40-year-old man has sudden tearing chest pain radiating to the back. BP is 170/90 in the right arm and 132/80 in the left. What should you avoid?
Answer: Antithrombotic drugs. Aortic dissection must be considered before giving antiplatelets, anticoagulants or thrombolytics, which can be fatal. Arrange urgent CT aortogram and control heart rate and BP.
- CT aortogram: This is the key investigation.
- IV morphine: Pain relief is appropriate.
- Calling the senior: Call early.
- IV labetalol: Used to control heart rate and BP in dissection.
2. A 58-year-old has heavy central chest pain. ECG shows ST elevation in II, III and aVF. What should be done before giving GTN?
Answer: Record right-sided leads (V4R) and check the BP. Inferior STEMI may involve the right ventricle. ST elevation in V4R means RV infarction: avoid nitrates and diuretics, give fluids if hypotensive, and activate the STEMI pathway.
- Wait for troponin: STEMI is diagnosed on the ECG.
- Exercise ECG: Contraindicated.
- Give GTN immediately at double dose: Right ventricular infarction makes GTN dangerous.
- Give furosemide: Harmful in RV infarction.
3. A man with chest pain took sildenafil last night. Can he have GTN?
Answer: No, risk of severe hypotension. Nitrates are contraindicated within 24 hours of sildenafil or vardenafil and 48 hours of tadalafil.
- Yes, at half dose: Still dangerous.
- Only if the ECG is normal: Irrelevant to the interaction.
- Yes, if BP is above 100: The interaction can still cause collapse.
- Yes, IV only: Route doesn't remove the interaction.
4. Which ECG pattern favours acute pericarditis over STEMI?
Answer: Widespread saddle ST elevation + PR depression. Pericarditis ECG: diffuse concave (saddle-shaped) ST elevation across multiple territories, PR depression (PR elevation in aVR), no reciprocal ST depression (except aVR, V1), no Q waves; evolves through stages over days. STEMI: convex ST elevation in a coronary territory with reciprocal depression, Q waves later. Echo looks for effusion; troponin may rise in myopericarditis.
- Regional ST elevation with reciprocal depression: Regional ST elevation with reciprocal depression indicates STEMI.
- New left bundle branch block: New LBBB is treated as an MI equivalent.
- Q waves in the inferior leads: Inferior Q waves indicate infarction.
5. A 55-year-old hypertensive man has sudden tearing chest pain radiating to the back, BP 190/100 in the right arm and 140/80 in the left. CT shows a dissection involving the ascending aorta. What is the management?
Answer: Emergency surgical repair. Stanford type A (ascending aorta involved) needs emergency surgery — risk of rupture, tamponade, coronary occlusion, aortic regurgitation. Type B (descending only) is managed medically (IV beta-blocker to HR < 60, SBP 100–120) unless complicated (malperfusion, rupture) → TEVAR. Risk factors: hypertension, Marfan/Ehlers–Danlos, bicuspid valve, pregnancy, cocaine. Never thrombolyse a possible dissection.
- Thrombolysis: Thrombolysis in dissection is catastrophic.
- Medical therapy alone: Medical therapy alone is for uncomplicated type B dissection.
- Elective repair in 6 weeks: Type A dissection needs emergency, not elective, repair.
6. A middle-aged hypertensive man has sudden tearing chest pain radiating to the back, then collapses. At autopsy, which finding is most likely?
Answer: Aortic dissection. Aortic dissection begins with an intimal tear; blood tracks through the weakened media (cystic medial degeneration), commonly in hypertension and Marfan syndrome. It causes tearing pain radiating to the back, unequal arm pulses and death by rupture into the pericardium (tamponade).
- Ruptured berry aneurysm: Causes sudden severe headache (subarachnoid haemorrhage).
- Saddle pulmonary embolus: Causes sudden breathlessness and collapse, not tearing back pain.
- Ruptured abdominal aortic aneurysm: Causes abdominal and back pain with a pulsatile mass.
- Left ventricular free-wall rupture: Occurs 3–7 days after an MI.
7. A man with end-stage renal failure has chest pain and a pericardial friction rub. What type of pericarditis is most typical?
Answer: Fibrinous pericarditis. Uraemia, early after myocardial infarction, rheumatic fever and SLE cause fibrinous pericarditis: a 'bread and butter' fibrin coat that rubs and causes a friction rub. Purulent is bacterial, caseous is tuberculous, and haemorrhagic is usually from cancer or TB.
- Purulent pericarditis: Caused by bacteria.
- Caseous pericarditis: Caused by tuberculosis.
- Haemorrhagic pericarditis: Typical of tumour spread or TB.
- Constrictive pericarditis from the start: A late result of TB or radiation, not the usual acute form.
References and dose sources
- NICE CG95: Recent-onset chest pain of suspected cardiac origin
- ESC 2023 guidelines for acute coronary syndromes
- HEART score
- NICE NG185 (ACS)
- ESC 2023
- NICE NG158 (VTE)
- BTS pleural disease
- Aspirin dosing: Drugs.com: Aspirin dosage (see also our aspirin dose page)
- Glyceryl trinitrate (GTN) dosing: Drugs.com: Nitroglycerin dosage (see also our glyceryl trinitrate (gtn) dose page)
- Morphine dosing: Drugs.com: Morphine dosage (see also our morphine dose page)
International guidance is linked where it reflects good practice. Where your hospital’s protocol differs, follow your hospital.