Multicenter Evaluation of the YEARS Criteria in Emergency Department Patients Evaluated for Pulmonary Embolism

BackgroundIt may be possible to safely rule out pulmonary embolism (PE) in patients with low pretest probability (PTP) using a higher than standard D-dimer threshold. The YEARS criteria, which include three questions from the Wells PE score to identify low-PTP patients and a variable D-dimer threshold, was recently shown to decrease the need for imaging to rule out PE by 14% in a multicenter study in the Netherlands. However, the YEARS approach has not been studied in the United States. MethodsThis study was a prospective, observational study of consecutive adult patients evaluated for PE in 17 U.S. emergency departments. Prior to diagnostic testing, we collected the YEARS criteria: Does the patient have clinical signs or symptoms of DVT? Does the patient have hemoptysis? Are alternative diagnoses less likely than PE? with YEARS (+) being any yes response. A negative D-dimer was<1000 mg/dL for YEARS (-) patients and<500 mg/dL for YEARS (+) patients. We calculated test characteristics and used Fisher's exact test to compare proportions of patients who would have been referred for imaging and patients who would have had PE missed. ResultsOf 1,789 patients, 84 (4%) had PE, 1,134 (63%) were female, 1,038 (58%) were white, and mean (SD) age was 48 (+/- 16) years. Using the standard D-dimer threshold, 940 (53%) would not have had imaging, with two (0.2%, 95% confidence interval [CI]= 0.02%-0.60%) missed PE. Using YEARS adjustment, 1,204 (67%, 95% CI= 65%-69%) would not have been referred for imaging, with six (0.5%, 95% CI= 0.18%-1.1%) missed PE, and using alternative diagnoses less likely than PE adjustment, 1,237 (69%, 95% CI= 67%-71%) would not have had imaging with six (0.49%, 95% CI= 0.18%-1.05%) missed PE. Sensitivity was 97.6% (95% CI= 91.7%-99.7%) for the standard threshold and 92.9% (95% CI= 85%-97%) for both adjusted thresholds. Negative predictive value (NPV) was nearly 100% for all approaches. ConclusionsD-dimer adjustment based on PTP may result in a reduced need for imaging to evaluate possible PE, with some additional missed PE but no decrease in NPV.