As a resident doctor, you will also often assess patients complaining of chest pain in the acute admissions setting and on the wards. Reviewing a patient with chest pain can be daunting whatever stage of training you are at.

The seriousness of chest pain varies from less concerning pain (i.e musculoskeletal pain) to life-threatening events. Always consider whether this might be a medical emergency & start with an ABCDE assessment. This article will focus on the clinical features that help differentiate cardiac and non-cardiac chest pain, the basic chest pain ‘work-up’ and when to escalate to the medical/cardiology registrar.

For the purpose of this article, chest pain secondary to coronary artery disease (CAD) will be referred to as ‘cardiac chest pain’. Other chest pain of cardiac origin is less common and will be covered in brief.

Common causes of chest pain

• Cardiac – Coronary artery disease, Aortic stenosis, Pericarditis, Aortic dissection.
• Pulmonary – Pneumonia with pleurisy, Pneumothorax, Pulmonary embolism.
• GI – GORD, Peptic ulcer disease, Oesophageal rupture.
• MSK – Costochondritis, Muscle strain, Rib fracture, Lytic bone lesions, Paget’s disease.

Clinical features helping differentiate cardiac and non-cardiac chest pain
In most cases, you will have enough time to take a focussed chest pain history. Get the particulars of the history by using SOCRATES. Specific features in the history of presenting complaint (HPC) make cardiac chest pain more or less likely. In most cases, patients with true cardiac chest pain will have a history of progressive angina. This is consistent with the coronary arteries narrowing over time and is a key aspect of the history to explore.

Focussed questions to help identify true cardiac chest pain should include:

• Before this episode, did you frequently get chest pain?
• Is this chest pain like your usual chest pain? If yes, is your usual pain on exertion? (i.e. angina).
• Does the pain occur EVERY time you exert yourself up to a particular level? (if yes, this is more likely to be cardiac).
• How long does it usually take the pain to disappear when you stop exerting yourself? (angina is typically relieved by rest or GTN within 5 minutes. Pain lasting hours/days makes cardiac chest pain less likely). Do not use GTN as a test for whether the pain is cardiac or not – it may help via the placebo effect or may not work in severe stenosis
• How has the pain progressed over time? – has it been occurring at progressively lower levels of exertion/more often? (i.e. due to progressive coronary artery narrowing).
• These questions also help assess ‘referred’ cardiac pain (e.g. shoulder, jaw and epigastric pain), presenting in isolation with no overt chest pain. Such cases are most often seen in female patients, the elderly and diabetics.

The second important aspect is assessing cardiac risk factors. The patient demographic (i.e. age, gender), PMH (i.e. diabetes, hypertension, hypercholesterolaemia, stroke disease), FH (i.e. cardiac events and stroke in first degree relatives) and social history (i.e smoking, obesity, sedentary lifestyle) all help build a picture of a patient’s cardiac risk factors.

Finally, establish the likelihood of true cardiac chest pain by placing the HPC into the context of the patient’s cardiac risk factors. For example, a cardiac event is highly likely in a patient with hypertension/diabetes/smoking excess, presenting with chest pain at rest on the background of the same pain on progressively less exertion. Conversely, a young patient with no cardiac risk factors may present with a first episode of chest pain lasting for hours/day with no correlation to exertion. This is less likely to be cardiac chest pain.

Although less commonly seen, it’s worth knowing some basic features of other causes of cardiac origin chest pain.

Aortic stenosis most commonly presents in elderly patients with progressive shortness of breath +/- chest pain on exertion, an ejection systolic murmur and clinical features of heart failure in the late stages.

Aortic dissection classically presents with acute onset ‘tearing’ chest pain radiating to the back, circulatory collapse and is more likely in connective tissue diseases (e.g. Marfans/Ehlers-Danlos).

Pericarditis presents as sharp chest pain worse on lying flat and there may be a preceding viral illness.

Non-cardiac chest pain
The commonly encountered non-cardiac causes of chest pain can broadly be divided anatomically into Pulmonary, GI and MSK causes.

Pulmonary causes usually present as pleuritic chest pain. This is classically a sharp pain on deep breathing. Causes include Pneumonia, PE and Pneumothorax. Beyond a careful history, a detailed respiratory examination is particularly important. Specifically remember to examine for signs of a DVT, calculate a Wells’ score and measure O2 saturation (+/- ABG if desaturating) when suspecting a PE.

The main GI cause to be aware of is GORD. You may commonly be asked to prescribe an antacid for ‘heartburn’. It is important to assess the patient to ensure there are no sinister features to suggest a cardiac event. Beware of the patient with ‘a bit of indigestion’ looking pale, sweaty and clammy! Patients with cardiac chest pain may have pain associated with food.

MSK pain is a diagnosis of exclusion after a detailed history, examination and investigations. It may affect anyone and usually, there is no explanation. Pain tends to be focal, present on chest movement & associated with tenderness. Sometimes patients with a chronic cough present with rib cage pain. Rib fractures are also a cause, especially in trauma patients and in elderly patients after a fall. In these patients, it’s important to rule out a pneumothorax and manage the pain adequately to help prevent pneumonia due to inadequate lung expansion because of pain.

Basic chest pain workup
ECG – A quick and easy investigation done in every patient. You should have a good reason to not do one. Look for ST interval changes, T wave inversions, pathological Q waves and new left bundle branch block. Changes that are dynamic or group to different areas of the heart are more suspicious therefore comparing against old ECGs & requesting serial ECGs is important.

Troponin – Consider discussing with seniors before sending one. They are high sensitivity tests which may be positive for a variety of reasons (other illnesses, renal impairment etc.) & are commonly mildly positive making interpretation difficult. Follow local guidelines on when best to repeat & how to interpret. Repeats are usually at 4,6 or 12 hours after the first sample or onset of chest pain.

Blood gas – If they are hypoxic or have shortness of breath, consider whether an ABG might be helpful. It is easiest to interpret when patients are off oxygen but if not possible, do note the number of litres or percentage the patient is receiving. This could point towards PE or a VBG may show lactic acidosis in sepsis.

Blood glucose – Hypoglycaemia can present non-specifically & acute cardiac events are at higher risk in those with hyperglycaemia (with diagnosed or undiagnosed diabetes).

Chest X-ray – Essential if suspecting pneumonia or pneumothorax. Consider whether a portable x-ray is needed (do you think the patient is well enough for you to leave them for 30 minutes?). Consider aortic dissection if a widened mediastinum is seen but urgent escalation to seniors for consideration of CT aortogram is best.

‘Routine’ blood tests – FBC, U&E’s, LFT’s, CRP and Coagulation. Look out for anaemia causing myocardial hypoperfusion. In such cases, you may see ECG changes across multiple coronary artery territories indicating global ischaemia.

Escalating care
Have a low threshold to escalate if at any point you’re concerned. Most new FY1s will escalate the first few chest pains they encounter & definitely escalate any patients with any features that concern you to seniors. ST elevation or new LBBB is usually urgently discussed with the cardiology registrar at the closest PCI centre, but even NSTEMI patients are frequently discussed with PCI centres. Patients with acute coronary syndrome that are medically managed, are usually seen by cardiology for risk stratification, modification of risk factors & further investigations e.g. coronary angiogram.

Take home points:

• Start with an ABCDE assessment when assessing a patient with chest pain.
• Take a focussed history concentrating on the nature of the chest pain and cardiac risk factors to help differentiate cardiac and non-cardiac chest pain.
• Interpret the ECG in the context of your focussed history and not in isolation.
• Compare ECG changes with previous ECGs & serial ECGs are useful in showing ‘dynamic changes’
• If your patient is acutely unwell escalate early to the medical registrar and the critical care/ITU team.
• Cardiac chest pain with new ST elevation or LBBB on the ECG requires immediate discussion with the cardiology registrar on call. Don’t wait for the troponin!

Dr Khudaim Mobeen FY3