PURPOSE: Pulmonary embolism is a major cause of maternal mortality. The use of multidetector row CT pulmonary angiogram (MDCTPA) has been increasing in the general population and in pregnancy. However, the use of CT has not been validated in pregnancy and its accuracy is questioned especially that some of the physiologic changes associated with pregnancy may affect technical adequacy. The purpose of this study is to evaluate the accuracy of MDCTPA in the diagnosis of pulmonary embolism in pregnancy.
METHODS: A retrospective review of 225 reports of MDCTPA performed on pregnant women was done for the workup of pulmonary embolism. Negative studies were divided into technically adequate or technically limited. The records were reviewed for ultrasound Doppler studies that were performed in the following 24 hours and chest radiographs performed within 24-48 hours.
RESULTS: Of 225 studies reviewed so far, 166 were technically adequate and were negative for pulmonary embolism. Seventy eight patients had leg Doppler studies performed and one patient also had upper extremity Dopplers done. Of those, 76/78 studies were negative for deep venous thrombi (DVT), resulting in a negative predictive value of 97.4%. Of the two positive studies, one was an upper extremity clot associated with a line. The remaining 88 had no further testing. Out of 48 technically limited studies that showed no evidence of pulmonary embolism, 28 had leg Doppler studies that were negative. Forty-seven out of 214 CT studies showed an alternative diagnosis; in 16/47, the chest radiograph was normal, 10/47 did not have a chest radiograph prior to the CT and in 12/47, the findings of the chest radiograph and CT correlated.
CONCLUSION: Technically adequate MDCTPA has a good negative predictive value for pulmonary embolism in pregnancy. Further studies need to be done to assess its accuracy and technical limitations in pregnancy.
CLINICAL IMPLICATIONS: MDCTPA is a promising technique in pregnancy. When compared to ventilation perfusion scans, it offers the advantage of alternative diagnoses and a likely lower amount of fetal radiation exposure.
DISCLOSURE: Ghada Bourjeily, No Financial Disclosure Information; No Product/Research Disclosure Information