American Society of Hirudotherapy

Cardiopulmonary bypass in humans: bypassing unfractionated heparin.

Review published in The Annals of thoracic surgery (2000)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Narrative reviewClinical TrialsDrug DevelopmentFrederiksen · The Annals of thoracic surgery, 2000

Abstract

Seven anticoagulants besides unfractionated heparin have been used for human cardiopulmonary bypass (CPB), mainly in patients with heparin-induced thrombocytopenia. The collective experience with these alternative anticoagulants provides a perspective on current efforts aimed at improving CPB anticoagulation. Unfortunately, each alternative currently lacks a standard dosing schedule and a reliable method of monitoring the adequacy of its anticoagulant effect during CPB. Most also lack proven antidotes. Thus, unfractionated heparin remains the anticoagulant of choice for standard CPB.

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

Publication typeJournal ArticleReview
Indexed MeSH termsAnticoagulantsCardiopulmonary BypassDose-Response Relationship, DrugDrug Administration ScheduleHeparinHumansThrombocytopenia

Summary

Seven anticoagulants besides unfractionated heparin have been used for human cardiopulmonary bypass (CPB), mainly in patients with heparin-induced thrombocytopenia. The collective experience with these alternative anticoagulants provides a perspective on current efforts aimed at improving CPB anticoagulation.

Why This Matters for Hirudotherapy

This article examined seven non-heparin anticoagulants used in human cardiopulmonary bypass, primarily in patients with heparin-induced thrombocytopenia, and reported that each lacks a standard dosing schedule, reliable intraoperative monitoring, and for most a proven antidote, so unfractionated heparin remains the anticoagulant of choice. For ASH, the topic is relevant because the alternative agents used in this setting include direct thrombin inhibitors such as lepirudin (recombinant hirudin) and bivalirudin (a hirudin analog), both derived from or modeled on the medicinal-leech anticoagulant hirudin, illustrating how leech-secretome compounds have entered clinical practice. An honest caveat is that the abstract does not name the individual seven agents or present new primary trial data, so it provides no direct efficacy or safety evidence for any single hirudin-related drug in CPB.

Citation

Cardiopulmonary bypass in humans: bypassing unfractionated heparin.

Frederiksen · The Annals of thoracic surgery, 2000

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

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