Macrotroponin: A Case Series and Review of the Literature

David Makarious; Yehuan Zhou; Jason Z Y Chung; Andrew T L Ong; Gopal Sivagangabalan; A Robert Denniss; Jay B Thakkar; Clara K Chow

doi:10.1016/j.hlc.2025.03.006

Macrotroponin: A Case Series and Review of the Literature

Heart Lung Circ. 2025 Jun 26:S1443-9506(25)00182-9. doi: 10.1016/j.hlc.2025.03.006. Online ahead of print.

Authors

David Makarious¹, Yehuan Zhou², Jason Z Y Chung³, Andrew T L Ong⁴, Gopal Sivagangabalan⁴, A Robert Denniss², Jay B Thakkar⁵, Clara K Chow²

Affiliations

¹ Cardiology Department, Westmead Hospital, Sydney, NSW, Australia; Faculty of Medicine, The University of Sydney, Sydney, NSW, Australia. Electronic address: david.makarious@health.nsw.gov.au.
² Cardiology Department, Westmead Hospital, Sydney, NSW, Australia; Faculty of Medicine, The University of Sydney, Sydney, NSW, Australia.
³ NSW Health Pathology - ICMPR, Westmead Hospital, Sydney, NSW, Australia.
⁴ Cardiology Department, Westmead Hospital, Sydney, NSW, Australia; Faculty of Medicine, University of Notre Dame, Sydney, NSW, Australia.
⁵ Cardiology Department, Westmead Hospital, Sydney, NSW, Australia.

PMID: 40579307
DOI: 10.1016/j.hlc.2025.03.006

Abstract

Cardiac troponin is a cornerstone biomarker in assessing myocardial injury, yet its interpretation is nuanced by conditions such as macrotroponins-benign immunoglobulin-troponin complexes that may result in false increases. This article presents three cases of macrotroponin-associated troponin increase, each demonstrating the diagnostic challenges posed by persistent troponin increases without clinical evidence of myocardial injury. Diagnostic workups, including imaging and immunoglobulin depletion assays, confirmed macrotroponin presence in all cases. A comprehensive literature review highlights the prevalence, mechanisms, and clinical implications of macrotroponins, emphasising the need for careful interpretation of troponin levels in biochemical-clinical discordance. The findings underscore the importance of collaboration between clinicians and laboratories to mitigate unnecessary investigations and optimise patient care.

Keywords: Biochemical-clinical discordance; Cardiac troponin; Immunoglobin complex; Macrotroponin.

Copyright © 2025 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Publication types

Review