The YEARS Algorithm: A clinical decision tool that incorporates differential D-Dimer cutoff values at presenation, developed to be fast and reduce the number of CTPA investigations

Three YEARS Items:

• clinical signs of DVT
• Hemoptysis
• Is Pulmonary Embolsim the most likely diagnosis?

D-Dimer Thresholds

• Any YEARS items = 500 ng/mL
• No YEARS items = 1000 ng/mL

Study Design: prospective, multi-center, cohort study

Study Outcomes: 

• Primary: Number of indepedently adjudicated events of VTE during 3 months of follow up
• Secondary: Number of required CTPA in the YEARS algorithm compared to Well's diagnostic algorithm

Exclusions: 1. Age < 18    2. Initiation of therapeutic anticoagulation 24 hours or more before evaluation    3. Life expectancy < 3 months   4. Pregnancy    5. Allergy to IV contrast

Findings: 

• 3465 patients were assessed of whom 456 (13%) were diagnosed with pulmonary embolism at baseline
• Of the 2946 (85%) patients who pulmonary embolism were ruled out at baseline and remained untreated, 18 patients were diagnosed with symptomatic VTE during 3 month follow up, of whom, six had fatal pulmonary embolism
• CTP was ont indicated in 1651 patients (48%) with the YEARS algorithm compared with 1174 (34%) of patients, if Wells rule and fixed D-Dimer threshold of less than 500 would have been applied

Author's Conclusion: The use of YEARS diagnostic algorithm can safely exclude patients with suspected PE and may decrease use of CTPA studies as compared to Wells' criteria

Of Note:

• Age adjusted D-Dimer (defined as age * 10 in patients > 50 years) has been prospectively validated to be safe and reduce the number of CTPA in patients low risk for PE
• if age adjusted D-Dimer was applied, the YEARS algorithm would have led to an absolute reduction of CTPA by only 8.7% compared to 14% as the study showed. 

References: Van der Hulle T, Cheung WY, Kooij S, et al. Simplified diagnostic management of suspected pulmonary embolism (the YEARS study): a prospective, multicentre, cohort study. Lancet. 2017; Van der Pol LM, Van der Hulle T, Cheung YW, et al. No added value of the age-adjusted D-dimer cut-off to the YEARS algorithm in patients with suspected pulmonary embolism. J Thromb Haemost. 2017;15(12):2317-2324. Righini M, Van es J, Den exter PL, et al. Age-adjusted D-dimer cutoff levels to rule out pulmonary embolism: the ADJUST-PE study. JAMA. 2014;311(11):1117-24.