Introduction
For chest pain, we must first determine the likely source of the pain from history and examination. Possible sources of pain: Cardiovascular (heart, vessels), Respiratory (lungs), Gastrointestinal (oesophagus, stomach), Musculoskeletal (ribs, muscles).
Gastrointestinal and musculoskeletal chest pain (including suspected rib fractures) generally do not require imaging.
Chest pain from a respiratory source (e.g. pulmonary embolism, pneumonia) is usually pleuritic in nature (sharp, worse on inspiration). Chest X-rays are the first line investigation for diagnosis in most cases. Exceptions are a suspected tension pneumothorax (which must be treated immediately before doing any investigations), and suspected pulmonary embolism (investigated with CTPA or VQ scan as first line).
Chest pain from a vascular source (e,g. aortic dissection) is rare, but extremely important not to miss. It may be described as tearing pain. Thoracic trauma and connective tissue disorders predispose to this. If the patient is stable enough, they may be investigated with CT. A widened mediastinum on CXR is a less reliable sign.
Cough and breathlessness can have a respiratory or cardiac cause.
- Dry cough, fine crackles – pulmonary fibrosis
- Productive cough, coarse crackles – pneumonia or heart failure
Heart failure is not a radiological diagnosis, i.e. we do not do CXRs to diagnose heart failure. However, the signs of heart failure can be seen on CXR.
Pneumonias can be seen on CXR as inflammatory changes or frank consolidation, there is seldom any need to do CT for this unless an atypical pneumonia is suspected.
HRCT (high resolution CT) thorax is used to investigate interstitial lung disease and pulmonary fibrosis.
Haemoptysis, especially in a smoker, is concerning for lung cancer and is investigated initially with a CXR. If the CXR appears normal but the symptoms persist, a CT thorax may be indicated. Infections (e.g. TB) and chronic coughing may also cause haemoptysis.