American Society of Hirudotherapy

Bivalirudin or Unfractionated Heparin in Acute Coronary Syndromes

Randomized controlled trial published in N Engl J Med (2015)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Randomized controlled trialDrug DevelopmentClinical TrialsValgimigli M et al. · N Engl J Med, 2015

Abstract

BACKGROUND: Conflicting evidence exists on the efficacy and safety of bivalirudin administered as part of percutaneous coronary intervention (PCI) in patients with an acute coronary syndrome. METHODS: We randomly assigned 7213 patients with an acute coronary syndrome for whom PCI was anticipated to receive either bivalirudin or unfractionated heparin. Patients in the bivalirudin group were subsequently randomly assigned to receive or not to receive a post-PCI bivalirudin infusion. Primary outcomes for the comparison between bivalirudin and heparin were the occurrence of major adverse cardiovascular events (a composite of death, myocardial infarction, or stroke) and net adverse clinical events (a composite of major bleeding or a major adverse cardiovascular event). The primary outcome for the comparison of a post-PCI bivalirudin infusion with no post-PCI infusion was a composite of urgent target-vessel revascularization, definite stent thrombosis, or net adverse clinical events. RESULTS: The rate of major adverse cardiovascular events was not significantly lower with bivalirudin than with heparin (10.3% and 10.9%, respectively; relative risk, 0.94; 95% confidence interval [CI], 0.81 to 1.09; P=0.44), nor was the rate of net adverse clinical events (11.2% and 12.4%, respectively; relative risk, 0.89; 95% CI, 0.78 to 1.03; P=0.12). Post-PCI bivalirudin infusion, as compared with no infusion, did not significantly decrease the rate of urgent target-vessel revascularization, definite stent thrombosis, or net adverse clinical events (11.0% and 11.9%, respectively; relative risk, 0.91; 95% CI, 0.74 to 1.11; P=0.34). CONCLUSIONS: In patients with an acute coronary syndrome, the rates of major adverse cardiovascular events and net adverse clinical events were not significantly lower with bivalirudin than with unfractionated heparin. The rate of the composite of urgent target-vessel revascularization, definite stent thrombosis, or net adverse clinical events was not significantly lower with a post-PCI bivalirudin infusion than with no post-PCI infusion. (Funded by the Medicines Company and Terumo Medical; MATRIX ClinicalTrials.gov number, NCT01433627.).

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

Publication typeJournal ArticleMulticenter StudyRandomized Controlled TrialResearch Support, Non-U.S. Gov't
Indexed MeSH termsAcute Coronary SyndromeAgedAnticoagulantsCombined Modality TherapyCoronary ThrombosisFemaleHeparinHirudinsHumansIncidenceInfusions, IntravenousMale

Summary

MATRIX trial randomized 7213 patients with ACS to bivalirudin vs UFH; no significant difference in major adverse cardiovascular events or net adverse clinical events.

Why This Matters for Hirudotherapy

This randomized controlled trial (MATRIX; N=7,213) compared bivalirudin versus unfractionated heparin in patients with acute coronary syndromes for whom PCI was anticipated, finding no significant differences in major adverse cardiovascular events (10.3% vs. 10.9%) or net adverse clinical events between groups, and no significant benefit from a post-PCI bivalirudin infusion. The abstract describes bivalirudin as an anticoagulant but does not mention leeches, hirudin, hirudotherapy, or any leech-derived origin for the drug. Accordingly, the article's relevance to ASH's domain is not established by the abstract.

Citation

Bivalirudin or Unfractionated Heparin in Acute Coronary Syndromes.

Valgimigli M et al. · N Engl J Med, 2015

Added to ASH library: May 27, 2026 · Site last updated: June 18, 2026

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