Table 2.

Biomarkers for the detection and diagnosis of myocardial injury in patients with COVID-19.

Potential mechanism of myocardial injury in COVID-19	Biomarkers of diagnosis
Acute coronary syndrome; Myocardial infarction condition	Trajectory of TnT concentration, and ECG changes (defined as ST segment elevation/ST-T0); coronary angiography Haemodynamic stress, quantified by BNP, and NT-proBNP concentrations Raised serum CK-MB levels are correlated with injury size, but are predictors of poor prognosis in COVID-19 patient [52]
Heart failure [43]	Elevated d-dimer, TnT, LDH, and IL plasma levels
Cytokine storm: myocardial dysfunction	Inflammatory, and cardiac biomarker testing (often need to exclude coexisting cardiac diagnoses) TnT, NT-pro BNP tests (for the analysis of potential myocardial injury, myocarditis, and cardiac dysfunction).
Myocarditis	Triple elevation in cardiac TnT (over 0.12 ng/mL) plus abnormalities on echocardiography, and/or ECG [60]. Cardiac MRI for tissue characterisation (Lake Louise criteria); endomyocardial biopsy in selected cases [61]
Stress cardiomyopathy	Cardiac imaging patterns; diagnosis of exclusion (typically after excluding coronary artery disease) POCUS: assessment of the left ventricle in a case of cardiomyopathy [62].

TnT, troponin; ECG, electrocardiogram; BNP, B-type natriuretic peptide; NT-proBNP, N-terminal B type natriuretic peptide; CK-MB, creatine Kinase-MB; COVID-19, corona virus disease 2019; LDH, lactate dehydrogenase; IL, interleukin; MRI, magnetic resonance imaging; Point-of-care ultrasound, POCUS.