Suspected Pulmonary Embolism in Pregnant Patient (1)

Figure: Transverse ultrasound image of the right femoral vein shows no evidence of deep vein thrombosis in a pregnant patient (7-week gestational age) presenting with acute dyspnea. Her subsequent CT pulmonary angiography shows multiple subsegmental pulmonary emboli.

Pulmonary Embolism in Pregnancy

• One in 1,000 to 10,000 pregnancies in prenatal period
• Risk of PE increases five fold during pregnancy
• Risk of PE increases with successive trimester and puerperal period (some studies demonstrated equal risks among different trimesters)
• Mortality up to 15-30%
• PE is a preventable cause of maternal death

Clinical Problems

• Difficult clinical diagnosis because of several conditions can mimic PE in pregnant patients, including normal physiologic change of pregnancy
• D-dimer assay not helpful if positive

Imaging Diagnosis

• No current standard guideline for imaging of PE in pregnant patients
• Algorithm depends on institutional preference, resource availability and individual radiologist/physician practice pattern
• Usual first-line imaging tests are chest radiography and lower extremity ultrasound

Reference:

Pahade JK, et al. Imaging pregnant patients with suspected pulmonary embolism: what the radiologist needs to know. Radiographics 2009; 10.1148/rg.293085226 (published online ahead of print on March 30, 2009)