American Society of Hirudotherapy

Antithrombotic Therapy for VTE Disease: Second Update of the CHEST Guideline and Expert Panel Report.

Research article published in Chest (2021)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Practice guidelineClinical TrialsDrug DevelopmentStevens et al. · Chest, 2021

Abstract

BACKGROUND: This is the 2nd update to the 9th edition of these guidelines. We provide recommendations on 17 PICO (Population, Intervention, Comparator, Outcome) questions, four of which have not been addressed previously. METHODS: We generate strong and weak recommendations based on high-, moderate-, and low-certainty evidence, using GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) methodology. RESULTS: The panel generated 29 guidance statements, 13 of which are graded as strong recommendations, covering aspects of antithrombotic management of VTE from initial management through secondary prevention and risk reduction of postthrombotic syndrome. Four new guidance statements have been added that did not appear in the 9th edition (2012) or 1st update (2016). Eight statements have been substantially modified from the 1st update. CONCLUSION: New evidence has emerged since 2016 that further informs the standard of care for patients with VTE. Substantial uncertainty remains regarding important management questions, particularly in limited disease and special patient populations.

Abstract sourced from PubMed (NCBI) for the cited record. See the original publication for the authoritative version.

Publication typeJournal ArticlePractice GuidelineResearch Support, Non-U.S. Gov't
Indexed MeSH termsAnticoagulantsAntiphospholipid SyndromeDrug Therapy, CombinationEvidence-Based MedicineFibrinolytic AgentsHumansHypotensionNeoplasmsPulmonary EmbolismVenous Thrombosis

Summary

This is the 2nd update to the 9th edition of these guidelines. We provide recommendations on 17 PICO (Population, Intervention, Comparator, Outcome) questions, four of which have not been addressed previously.

Why This Matters for Hirudotherapy

This practice guideline provides 29 guidance statements—13 graded as strong recommendations—on antithrombotic therapy for VTE disease, covering initial management through secondary prevention and post-thrombotic syndrome risk reduction, using GRADE methodology with four new statements added since the prior update. The relevance to ASH's domain is indirect: while hirudin is an anticoagulant, these guidelines address modern pharmacological anticoagulation for VTE. No leeches, hirudin products, or hirudotherapy are mentioned in the abstract. The guideline's focus on evidence-based antithrombotic drug selection and management bears no demonstrated connection to therapeutic leeching or the leech secretome.

Citation

Antithrombotic Therapy for VTE Disease: Second Update of the CHEST Guideline and Expert Panel Report.

Stevens et al. · Chest, 2021

Added to ASH library: May 28, 2026 · Site last updated: June 18, 2026

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