Reference Values

 <20 ng/L

Elevated cTnT is diagnostic of myocardial necrosis but does not identify the mechanism. Myocardial necrosis can be present in a number of clinical scenarios. 

The term myocardial infarction (MI) should only be used when there is evidence of myocardial necrosis in a clinical setting consistent with acute myocardial ischemia.  Under these conditions MI may be defined as:

Detection of a rise and/or fall of cTnT with at least one value > 19 ng/L and with at least one of the following:

1. Symptoms of ischemia (i.e. chest pain)
2. New or presumed new significant ST-T changes or new LBBB or Q waves on EKG
3. Imaging evidence of new loss of viable myocardium or new regional wall motion abnormality
4. Identification of intracoronary thrombus

* Third Universal Definition of MI. Circulation. 2012;126:2020-2035

Critical value:  >99 ng/L (Huntsville Hospital Emergency Department Patients, all Madison Hospital patients and Reference Lab patients.)