No added value of the age-adjusted D-dimer cut-off to the YEARS algorithm in patients with suspected pulmonary embolism

Background The YEARS algorithm was designed to simplify the diagnostic work-up of pulmonary embolism (PE) and to reduce the number of necessary computed tomography pulmonary angiography (CTPA) scans. An alternative strategy to reduce the number of CTPAs is the age-adjusted D-dimer cut-off (ADJUST) in patients aged 50 years or older. We aimed to investigate whether a combination of both diagnostic strategies might save additional CTPAs. Methods The YEARS algorithm consists of three items (clinical signs of deep venous thrombosis, hemoptysis, “PE most likely diagnosis”) with simultaneous D-dimer testing using a pre-test dependent threshold. We performed a post hoc analysis in 3465 patients managed according to YEARS to compare the number of patients managed without CTPA scans and associated diagnostic failures in hypothetical scenarios with different YEARS-ADJUST combinations. Results Following the YEARS algorithm, 1651 patients (48%) were managed without CTPA; PE was diagnosed in 456 (13%) patients at baseline and 18 patients with initial normal testing suffered venous thrombo-embolism (VTE) during 3-month follow-up (failure rate 0.61%, 95%CI 0.36-0.96). When ADJUST would have been fully integrated in YEARS, 1627 patients (47%) would have been managed without CTPA (absolute decrease of 0.69%; 95%CI -1.7-3.0), at cost of 4 additional missed PE diagnoses at baseline, for a projected 3-month VTE failure rate of 0.75% (95%CI 0.49-1.13). None of the other studied scenario's showed relevant improvements in efficiency as well, but all led to more missed diagnoses. Conclusion In our cohort, there was no added value of implementing ADJUST in the YEARS algorithm. This article is protected by copyright. All rights reserved.