Correlations between high sensitive troponin I and acute myocarditis extent in cardiac magnetic resonance imaging

To assess the correlation between high sensitive troponin I (HsTnI) levels and myocardial damage on cardiac magnetic resonance (CMR) represented by late gadolinium enhancement (LGE) percentage in patients diagnosed with myocarditis.

Retrospective analysis of consecutive patients who underwent CMR following a suspected diagnosis of acute myocarditis, comparing CMR findings viewed as LGE percentage and HsTnI levels.

Between February 2016 and December 2021, 101 patients underwent CMR for suspected myocarditis in Rambam Medical Center. Seventy-six (75.2%) patients with a documented diagnosis of acute myocarditis in the medical records based on clinical history and lab work were included in the final analysis. The median age was 30 years [interquartile range (IQR) 22,42] and 62 patients (81.6%) were male. Thirty-four patients (44.7%) had a history of fever and 26 (34.2%) had upper respiratory tract symptoms. The median maximal HsTnI was 3935 ng/l (1165,10 380) and the median C-reactive protein (CRP) was 7.97 mg/l (2.35,19.28). The median LGE percentage was 4.65% (2.6,8.5) and ventricular ejection fraction 60% (56.00,64.75).Linear association was found between LGE (%) and maximal HsTnI (ng/l) value with r  = 0.49 ( P  < 0.001). After including only patients in whom the CMR was performed within 5 days of the maximal HsTnI the correlation improved to r  = 0.67 ( P  < 0.001).

HsTnI is an indicator for myocardial damage extent resulting from inflammation in patients with acute myocarditis.