Pitfalls in the diagnostic management of pulmonary embolism in pregnancy

Women are at increased risk of venous thromboembolism (VTE) during pregnancy and VTE remains one of the main causes of maternal mortality in developed countries (Konstantinides SV, et al. Eur Heart J 2014; 35(43):3033-69, 69a-69k). Although an accurate diagnosis of acute pulmonary embolism (PE) in pregnant patients is thus of crucial importance, the diagnostic management of suspected PE is challenging for this specific patient category. As D-dimer levels increase physiologically throughout pregnancy, the optimal D-dimer threshold to rule out PE during pregnancy remains unknown. Available clinical decision rules, such as the Wells score and the revised Geneva rule, have not been evaluated in pregnant patients. Also, although ventilation-perfusion (V-Q) lung scan and computed tomography pulmonary angiography (CTPA) can be used in the pregnant population, both modalities have disadvantages of radiation exposure to both mother and foetus. Because of these uncertainties, clinical guidelines provide contradicting recommendations with weak levels of evidence. In this review, we illustrate these dilemmas and provide practice recommendation for the diagnostic management of suspected PE in pregnancy using two real-life patient cases.