At 32 weeks’ gestation, PE remains likely after a negative leg ultrasound. Chest radiography is normal; timely V/Q SPECT and pregnancy-adapted CTPA

Question

At 32 weeks’ gestation, PE remains likely after a negative leg ultrasound. Chest radiography is normal; timely V/Q SPECT and pregnancy-adapted CTPA are both available. Which next test best balances diagnostic performance and radiation?

Accepted Answer

Proceed with V/Q imaging after informed discussion, while recognizing pregnancy-adapted CTPA is also acceptable

Answer

Choose conventional pulmonary angiography because non-invasive tests are unreliable in pregnancy

Answer

Repeat leg ultrasound daily until delivery and treat only if a proximal DVT appears

Answer

Use an unadjusted D-dimer alone because a negative leg ultrasound makes PE probability low

Answer

Avoid thoracic imaging until delivery because fetal radiation from either test exceeds teratogenic thresholds

Pulmonary embolism in pregnancy — RCPSC EM MCQ

At 32 weeks’ gestation, PE remains likely after a negative leg ultrasound. Chest radiography is normal; timely V/Q SPECT and pregnancy-adapted CTPA are both available. Which next test best balances diagnostic performance and radiation?