Feature Article

Investigation for pulmonary embolism: it all depends on the risk

Adrian Selim, Abdullah Omari



The presentation of pulmonary embolism is variable, which can lead to delays in diagnosis and treatment. A high level of clinical suspicion and the ability to stratify patients according to their level of risk are therefore needed to prevent potentially fatal outcomes. This article provides a framework for the investigative approach to patients with suspected pulmonary embolism.

Key Points

  • In most patients, pulmonary embolism is suspected based on the presence of dyspnoea, chest pain, presyncope or syncope, and/or haemoptysis.
  • A negative D-dimer assay in a nonhigh-risk outpatient can safely exclude pulmonary embolism.
  • If a pregnant woman is suspected of having a pulmonary embolism and the chest x-ray is normal, ventilation perfusion scintigraphy scan may be preferable to computed tomographic pulmonary angiography because of lower maternal radiation exposure.
  • The finding of a proximal lower limb deep vein thrombosis on compression ultrasonography in a patient suspected of having a pulmonary embolism is sufficient to diagnose pulmonary embolism when further imaging modalities are not readily available or their use is prohibited.
  • Use of the simplified Pulmonary Embolism Severity Index may help select patients with pulmonary embolism who may be suitable for outpatient care or early hospital discharge.

    Picture credit: © John Bavosi/SPL.