In evaluating suspected PE, a positive D-Dimer most commonly leads to which next test?

In evaluating suspected PE, a positive D-Dimer most commonly leads to which next test?

• A. D-Dimer
• B. CTA
• C. CXR
• D. EKG

Answer: (B)

D-dimer is a sensitive screening test for suspected PE: a negative result makes PE unlikely, but a positive result isn’t specific and needs imaging to confirm. The next test chosen is CT pulmonary angiography because it directly visualizes the pulmonary arteries and can detect emboli, providing both confirmation and information on location and extent. It’s fast, widely available, and generally the most informative imaging modality in this scenario. Chest X-ray and EKG can be abnormal with PE but do not confirm it, and repeating the D-dimer won’t establish the diagnosis. If CTA isn’t possible, alternatives like a ventilation-perfusion scan or other imaging may be considered.

D-dimer is a sensitive screening test for suspected PE: a negative result makes PE unlikely, but a positive result isn’t specific and needs imaging to confirm. The next test chosen is CT pulmonary angiography because it directly visualizes the pulmonary arteries and can detect emboli, providing both confirmation and information on location and extent. It’s fast, widely available, and generally the most informative imaging modality in this scenario. Chest X-ray and EKG can be abnormal with PE but do not confirm it, and repeating the D-dimer won’t establish the diagnosis. If CTA isn’t possible, alternatives like a ventilation-perfusion scan or other imaging may be considered.