Assessing recurrence risk following acute venous thromboembolism: use of algorithms

Purpose of reviewVenous thromboembolism (VTE) is a chronic disease, associated with a significant rate of recurrence, lower in patients with events provoked by transient risk factors and higher in unprovoked cases. Short-term treatment is indicated for provoked VTE, long-term treatment should be considered for unprovoked. The aim of this review is to evaluate the risk factors for recurrence and the decisional algorithms available to guide patients' management.Recent findingsTo identify patients who carry a high recurrent risk and require long-term treatment, three algorithms have been proposed: the HERDOO2, the Vienna prediction model, and the DASH score. All identify male sex and elevated D-dimer levels as important risk factors for recurrence. However, important differences among the models should be outlined: in the HERDOO2 model, D-dimer levels are measured during anticoagulation and not after its withdrawal; furthermore, it indicates age greater than 65 as a risk factor for recurrence, whereas the DASH score attributes a higher risk to age less than 50. The Vienna model is complex for routine use.SummaryFurther studies are needed to clarify these discrepancies. A management study based on D-dimer levels after anticoagulation withdrawal is ongoing and could indicate a simple way to safely manage these patients.