Background: The clinical diagnosis of pulmonary embolism (PE) can be challenging given its variable presentation, thus requiring dependence on objective testing. Decision instruments such as PERC and the Wells’ score help stratify patients to low or high probability, enabling focused use of CT pulmonary angiography (CTPA) for diagnosis. However, despite these algorithms, there is evidence of increasing use of CTPA along with diminishing diagnostic rate (less than 10%). This combination results in the overdiagnosis of subsegmental PEs, unnecessary exposure to radiation and false positive results. These issues are compounded in patients with pregnancy. While we know that pregnancy increases risk of venous thromboembolism (VTE) our testing rates far exceed the added risk exposing thousands of women to the afore mentioned potential harms.
In 2017, the YEARS algorithm established a simplified algorithm for evaluation with a two-tiered D-dimer threshold in an effort to reduce the number of patients getting CTPA (van der Hulle 2017). The YEARS algorithm asks three questions: 1) Are there clinical signs of DVT? 2) Does the patient have hemoptysis? and 3) is PE the most likely diagnosis. If the answer to all 3 questions is no, the D-dimer threshold is set at 1000 ng/mL FEU (500 ng/mL DDU) and if the answer is “yes” to any of the 3 questions, the D-dimer threshold is set at 500 ng/mL (250 ng/mL DDU). However, this study had very few pregnant women enrolled....Read More