Diagnosis of deep vein thrombosis and pulmonary embolism.

INTRODUCTION Diagnosing deep vein thrombosis (DVT) and pulmonary embolism (PE) in pregnancy is challenging. Many of the common diagnostic tests, including compression ultrasonography (CUS), ventilation-perfusion scintigraphy (VQ scan) and helical computed tomography (hCT) that have been extensively investigated in non-pregnant patients, have not been appropriately validated in pregnancy. Extrapolating results of diagnostic studies of DVT and PE in non-pregnant patients to those who are pregnant may not be correct because during pregnancy, physiologic and anatomic changes may affect diagnostic test results, presentation and natural history of VTE. METHODS We performed a systematic analysis of published studies addressing accurate diagnostic testing for DVT and PE in pregnancy to determine the accuracy of these tests in pregnancy. RESULTS Our initial search yielded 530 articles of which four remained for inclusion, three studies investigating diagnostic testing in patients with a clinical suspicion of DVT or PE and one study in patients with a clinical suspicion of PE. CONCLUSIONS From our systematic analysis of published studies investigating diagnostic testing for a clinical suspicion of DVT in pregnancy we conclude that; (i) two studies support withholding anticoagulant therapy in pregnant women with a clinical suspicion of DVT and normal results on serial IPG (impedance plethysmography), however, IPG is no longer used; (ii) one study demonstrated that a normal CUS at presentation combined with a normal D-dimer test or an abnormal D-dimer test combined with normal serial CUS appears promising for safely excluding DVT in pregnant patients, but too few patients were included in this pilot-study to draw firm conclusions; and (iii) one study investigated pregnant patients with a clinical suspicion of PE and this study concluded that in patients with normal or non-diagnostic VQ scans, withholding anticoagulant therapy might be safe, but this needs confirmation in larger studies. Recommendations on diagnostic testing of pregnant patients with a clinically suspected DVT or PE are provided.