American Society of Hirudotherapy

Comparison of Screening Scores for Heparin- Induced Thrombocytopenia After Cardiopulmonary Bypass

Research article published in Journal of cardiothoracic and vascular anesthesia (2022)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Research reportClinical TrialsCutler et al. · Journal of cardiothoracic and vascular anesthesia, 2022

Abstract

OBJECTIVES: To compare screening scores for heparin-induced thrombocytopenia (HIT) after cardiopulmonary bypass (CPB). DESIGN: Retrospective cohort study. SETTING: Cardiothoracic surgery units within a large tertiary healthcare facility from September 2010 to January 2020. PARTICIPANTS: All adult patients tested for heparin-induced platelet antibody (HIPA) within 2 weeks after surgery requiring CPB. INTERVENTIONS: Using data available to providers at the time HIPA were checked, the 4T's Score, a modified 4T's Score, and a score proposed by Lillo-Le Louet (LLL) et al. were calculated. A retrospective chart review was performed for each patient to determine actual presence of HIT, and screening scores were compared for accuracy. MEASUREMENTS AND MAIN RESULTS: Criteria for inclusion were met in 266 patients. Of these, 34 (12.8%) were high likelihood of HIT, 16 (6.0%), additional patients were clinically ambiguous, and 216 (81.2%) were high likelihood of alternative cause for thrombocytopenia. HIPA tests done before postoperative day 5 were not associated with any high-likelihood cases of HIT regardless of preoperative heparin exposure. Although traditional 4T's ≥4, modified 4T's ≥3, and LLL ≥2 had statistically similar sensitivity for predicting HIT, the modified 4T's and LLL had superior specificity (p < 0.001). CONCLUSIONS: Appropriate screening for HIT curbed inappropriate HIPA testing, and reduced the need for empirical treatment while awaiting confirmatory test results. Traditional 4T's was statistically inferior to both the LLL score and a modified version of the 4T's to screen for HIT within 2 weeks of CPB.

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

Publication typeJournal Article
Indexed MeSH termsAdultAnticoagulantsBlood PlateletsCardiopulmonary BypassHeparinHumansRetrospective StudiesThrombocytopenia

Summary

Peer-reviewed clinical and outcomes research relevant to medicinal leech therapy and its biology. Indexed in PubMed and verified against the NCBI record.

Why This Matters for Hirudotherapy

This retrospective cohort (266 adults tested for heparin-induced platelet antibodies within two weeks of cardiopulmonary bypass) compared the 4T's, a modified 4T's, and the Lillo-Le Louet score for screening heparin-induced thrombocytopenia (HIT); the abstract reports the traditional 4T's was statistically inferior, while the modified 4T's and LLL had superior specificity (p < 0.001), and that appropriate screening reduced unnecessary antibody testing and empirical treatment. For hirudotherapy this is contextual rather than direct: HIT is precisely the setting where a non-heparin anticoagulant matters, and leech-derived molecules such as hirudin act independently of platelet factor 4, which frames why the medicinal-leech secretome is studied as an anticoagulation alternative. Honest caveat: this study is about heparin-complication screening tools in cardiac-surgery patients and does not examine leeches or any leech-derived therapy, so it informs the surrounding anticoagulation evidence picture only indirectly.

Citation

Comparison of Screening Scores for Heparin- Induced Thrombocytopenia After Cardiopulmonary Bypass.

Cutler et al. · Journal of cardiothoracic and vascular anesthesia, 2022

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

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