Acute myocarditis is a potentially life-threatening condition, but confirming the diagnosis often requires cardiac magnetic resonance (CMR), which is not always readily available. A retrospective cohort study published in Open Heart assessed whether high-sensitivity troponin T (hsTnT) could act as a reliable biomarker to guide decision-making in suspected cases.

The analysis included 244 consecutive patients with clinical suspicion of myocarditis, who underwent CMR, with acute myocarditis confirmed in 72 individuals. Significant differences in age, cardiac function, and biomarker levels were observed between those with and without confirmed disease.

Receiver operating characteristics analysis showed that hsTnT had strong diagnostic value, with sensitivity of 0.92 and a negative predictive value of 0.96. A threshold cut-off of ≤18 pg/mL hsTnT was identified as a safe rule-out threshold, suggesting that patients below this level have a very low likelihood of myocarditis.

The findings suggest that while CMR remains the non-invasive gold standard, hsTnT testing may streamline triage and reduce unnecessary imaging in patients with suspected acute myocarditis.