CT Chest Without IV Contrast There is no relevant literature to support the use of CT chest without IV contrast for suspected PE in a pregnant patient. CTA Chest With IV Contrast with CTV Lower Extremities Older literature shows that the field of view for CTA can be extended to include the lower extremities so that both the pulmonary arteries and the deep veins of the leg can be imaged during the same imaging session [25,26]. However, this protocol is very rarely used at present, owing to the accuracy of performing US for DVT and the increased burden of contrast and radiation for the associated extended craniocaudal field of view [27]. CTA Triple Rule Out There is no relevant literature to support the use of CTA triple rule out for suspected PE in a pregnant patient. Arteriography Pulmonary with Right Heart Catheterization There is no relevant literature to support diagnostic catheterization for PE in pregnant patients. This invasive procedure has an estimated morbidity and mortality of 3.5% to 6% and 0.2% to 0.5%, respectively [32,33]. If IV contrast is used, CTPA should be performed for diagnosis. The role of catheterization in intervention is not considered in this document. MRA Pulmonary Arteries Without and With IV Contrast In general, gadolinium-based contrast agents should be administered with caution to pregnant or potentially pregnant patients [66]. Because there are alternative methods to evaluate for PE in pregnancy that have greater benefit to the patient or fetus when compared with possible but unknown risk of fetal exposure to free gadolinium ions, MRA without and with IV contrast is rarely, if ever, performed. MRA Pulmonary Arteries Without IV Contrast Noncontrast MRA sequences alone for PE have been reported but remain investigational [43]. There is limited literature to support the use of noncontrast MRA of the pulmonary arteries for the evaluation of PE, including among pregnant patients [24,34].
Suspected Pulmonary Embolism PCAs. CT Chest Without IV Contrast There is no relevant literature to support the use of CT chest without IV contrast for suspected PE in a pregnant patient. CTA Chest With IV Contrast with CTV Lower Extremities Older literature shows that the field of view for CTA can be extended to include the lower extremities so that both the pulmonary arteries and the deep veins of the leg can be imaged during the same imaging session [25,26]. However, this protocol is very rarely used at present, owing to the accuracy of performing US for DVT and the increased burden of contrast and radiation for the associated extended craniocaudal field of view [27]. CTA Triple Rule Out There is no relevant literature to support the use of CTA triple rule out for suspected PE in a pregnant patient. Arteriography Pulmonary with Right Heart Catheterization There is no relevant literature to support diagnostic catheterization for PE in pregnant patients. This invasive procedure has an estimated morbidity and mortality of 3.5% to 6% and 0.2% to 0.5%, respectively [32,33]. If IV contrast is used, CTPA should be performed for diagnosis. The role of catheterization in intervention is not considered in this document. MRA Pulmonary Arteries Without and With IV Contrast In general, gadolinium-based contrast agents should be administered with caution to pregnant or potentially pregnant patients [66]. Because there are alternative methods to evaluate for PE in pregnancy that have greater benefit to the patient or fetus when compared with possible but unknown risk of fetal exposure to free gadolinium ions, MRA without and with IV contrast is rarely, if ever, performed. MRA Pulmonary Arteries Without IV Contrast Noncontrast MRA sequences alone for PE have been reported but remain investigational [43]. There is limited literature to support the use of noncontrast MRA of the pulmonary arteries for the evaluation of PE, including among pregnant patients [24,34].