How is a Pulmonary Embolism (PE) typically diagnosed?

A Pulmonary Embolism (PE) is typically diagnosed using a CT Angiogram (CTA) of the chest, which is the most sensitive and specific imaging modality for this condition. The CTA provides detailed images of the blood vessels in the lungs and can directly visualize the presence of any emboli obstructing blood flow in the pulmonary arteries.

While a chest X-ray may be part of the initial evaluation, it is generally not definitive for diagnosing PE and may appear normal in many cases of embolism. Cardiac MRI is less common in the acute setting and is primarily used for other cardiac conditions. Blood tests, such as D-dimer testing, can help rule out PE, as elevated levels may indicate clot formation; however, these tests are not diagnostic on their own and are generally used in conjunction with imaging studies.

In summary, the CTA is preferred due to its ability to provide clear images of the pulmonary vasculature and directly identify any pulmonary emboli.