Strategies for evaluating patients with acute pulmonary embolism

Based on the results of the Prospective Investigation of Pulmonary Embolism Diagnosis II (PIOPED II), Stein and colleagues have made recommendations for the assessment of patients with suspected pulmonary embolism (PE). The clinical highlights are summarized as follows:

•An objective assessment of the clinical probability of PE is warranted in all patients in whom PE is suspected, and it should be done before imaging studies.

•If this assessment suggests that the probability of PE is low or intermediate, d-dimer testing is warranted. d-Dimer should be measured by the quantitative rapid enzyme-linked immunosorbent assay.

•The combination of a negative d-dimer result and low or moderate clinical probability often safely excludes the diagnosis of PE.

•An abnormal d-dimer finding indicates the need for further diagnostic testing. Contrast-enhanced CT angiography and CT venography are recommended.

•If the assessment indicates that the clinical probability of PE is high, d-dimer testing is not helpful, and the patient should be evaluated with CT angiography/CT venography. Anticoagulant therapy should be administered while awaiting the results of diagnostic studies.

Stein and colleagues note that venous ultrasonography before CT angiography/CT venography is optional. They also say that ventilation/perfusion lung scanning may be the preferred imaging method in pregnant women.