American Society of Hirudotherapy

Anticoagulation management and poor clinical outcomes in tamariki and rangatahi with rheumatic heart disease following mechanical valve replacement surgery in Counties Manukau.

Research article published in The New Zealand medical journal (2025)

Last Updated: June 18, 2026Reviewed by: ASH Editorial Board
Research article — evidence reviewArticle reference
Evidence: Observational studyClinical TrialsDrug DevelopmentTangirala et al. · The New Zealand medical journal, 2025

Abstract

AIM: Rheumatic heart disease (RHD) causes significant cardiovascular morbidity and mortality, with persisting inequitably high rates in Māori and Pacific tamariki and rangatahi. Mechanical valve replacement surgery is required for people with severe RHD and requires lifetime anticoagulation. Contemporary data regarding anticoagulation management and outcomes for tamariki and rangatahi following mechanical valve replacement surgery for RHD are lacking. We aimed to describe patient characteristics, anticoagulation management practices and complications in a cohort of tamariki and rangatahi ≤25 years of age. METHODS: A retrospective observational study of patients aged ≤25 years with RHD and mechanical valves, living in Counties Manukau, South Auckland, 2016-2021, was conducted. RESULTS: A total of 53 patients were identified. The median age at time of first mechanical valve surgery was 15 years (range 4-23 years). Nineteen percent of the cohort were Māori and 81% were Pacific peoples. The median duration of anticoagulation was 4 years (range 0.5-18 years). The most common method of monitoring was via the community laboratory service and general practitioner. There were 38 individuals who had ≥1 anticoagulation-related hospitalisation. There were 80 anticoagulation-related hospitalisations: 52% were due to a subtherapeutic international normalised ratio (INR) without clinical complication; 15% had a supratherapeutic INR without clinical complication; 14% haemorrhage; 9% stroke; 6% other thromboembolic events; and 4% prosthetic valve thrombosis. Five deaths occurred between 2016 and 2021. CONCLUSION: The majority of the cohort had serious anticoagulation-related hospitalisation events, and 10% died. Urgent efforts are required to improve services for anticoagulation monitoring and management and clinical outcomes in young adults following mechanical valve surgery for RHD.

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

Publication typeJournal ArticleObservational Study
Indexed MeSH termsHumansRheumatic Heart DiseaseAnticoagulantsRetrospective StudiesMaleFemaleNew ZealandAdolescentYoung AdultChildHeart Valve Prosthesis ImplantationChild, Preschool

Summary

Rheumatic heart disease (RHD) causes significant cardiovascular morbidity and mortality, with persisting inequitably high rates in Māori and Pacific tamariki and rangatahi. Mechanical valve replacement surgery is required for people with severe RHD and requires lifetime anticoagulation.

Why This Matters for Hirudotherapy

This retrospective observational study described anticoagulation management and outcomes in 53 patients aged ≤25 years with rheumatic heart disease and mechanical valves in South Auckland (2016–2021), finding that the majority had anticoagulation-related hospitalizations and 10% died. It is relevant to ASH's domain broadly through its focus on anticoagulation management and its complications—the therapeutic context shared by hirudin-based anticoagulants. However, the abstract makes no reference to leeches, hirudotherapy, or hirudin derivatives. Its relevance is indirect, limited to the general anticoagulation management landscape.

Citation

Anticoagulation management and poor clinical outcomes in tamariki and rangatahi with rheumatic heart disease following mechanical valve replacement surgery in Counties Manukau.

Tangirala et al. · The New Zealand medical journal, 2025

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

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