Possible mechanisms behind cardiac troponin elevations

Abstract

Cardiac-specific troponins are elevated in blood following cardiac injury and are the preferred diagnostic biomarkers when acute myocardial infarction is suspected clinically. Cardiac troponin (cTn) elevations are also observed in clinical conditions without obvious connection to cardiac injury. Irrespective of the underlying condition, cTn elevation is linked to a poor prognosis, even if the elevation is stable over time. Here, we explore mechanisms that may lead to cTn elevations, including necrosis, apoptosis, necroptosis, cell wounds and decreased clearance. The aim is to broaden the perspective of how we interpret unexpected cTn elevations in patients. The cTn elevations may not be able to serve as direct proof of myocardial necrosis especially in the absence of a clear-cut reason for its release. Abbreviations: AMI: acute myocardial infarction; cTn: cardiac troponin; cTnI: cardiac troponin I; cTnT: cardiac troponin T; MLKL: mixed lineage kinase domain-like; TUNEL: terminal deoxynucleotidyl transferase nick end labeling.

Keywords: Cardiac troponin I; apoptosis; cardiac troponin T; clearance; myocardial injury; necrosis; release; reversible.