Van der Hulle T et al. Simplified diagnostic management of suspected pulmonary embolism (the YEARS study): a prospective, multicentre, cohort study. Lancet. 2017; 390:289-297. PMID: 28549662
Wells’ scores help stratify patients suspected of having a pulmonary embolism, enabling a more selective use of CTPA. Wells’ has been recommended and shown to be safe and accurate, but it’s complexity and differences in clinical practice cause many physicians to skip the algorithm and go straight to advanced imaging. There is evidence of increasing imaging use with diminishing diagnostic rate (<10%). This leads to overdiagnosis of subsegmental PEs, increased radiation exposure, and increased false positive results. This study aims to present a simplified algorithm for evaluation with a two-tiered D-dimer threshold to safely reduce the number of CTPA imaging performed
Prospective cohort study conducted in 12 hospitals across the Netherlands in consecutive hemodynamically stable patients with suspected acute pulmonary embolism from October 5th, 2013 until July 9th, 2015. In these patients, the algorithm was applied by evaluating the presence of the 3 YEARS items: clinical signs of DVT, hemoptysis, and was pulmonary embolism most likely diagnosis, and the result of a quantitative D-dimer test. In patients with no YEARS items and D-dimer <1,000, pulmonary embolism was excluded and no CTPA was performed. In patients with one or more YEARS items and D-dimer <500, pulmonary embolism was excluded and no CTPA was performed. All other patients received CTPA.
When compared to Wells’ Score with a D-dimer cutoff of 500 ng/mL, the YEARS algorithm reduced CTPA by 14%. In this study, 2,946 patients were ruled out for pulmonary embolism using the YEARS algorithm. Of the 1,629 patients who were ruled out without the use of CTPA, 7 had symptomatic VTE during the 3 month follow up period, 2 of which were fatal. 1,317 patients were managed with CTPA and of those patients, 11 had symptomatic VTE during the 3 month follow up period, 4 of which were fatal.
When using the YEARS algorithm, knowledge of the D-dimer results likely influences the already subjective assessment of whether PE was the “most likely diagnosis”. Furthermore, the applicability of this algorithm is limited by the fact that the study population had a higher prevalence of pulmonary embolism than that observed in North American cohorts. Currently, Wells’ is still the preeminent algorithm in the workup of pulmonary embolism and and efforts should be directed towards consistently using it where indicated.