Key Points
ÎÎElevated troponin is a sensitive and specific indication of cardiac
myonecrosis, which releases troponin from myocytes into the systemic
circulation.
ÎÎIn and of itself, elevated troponin does not indicate myocardial infarction
(MI) (myonecrosis due to ischemia). Rather, it is nonspecific relative to the
etiology of cardiac myonecrosis.
• Troponin elevation occurs in many nonischemic clinical conditions.
• As assays become more sensitive, more conditions that result in low-level troponin
elevations will be identified.
ÎÎAn elevated troponin level must always be interpreted in the context of the
clinical presentation and pre-test likelihood that it represents MI.
ÎÎTroponin testing is recommended for diagnosis of MI in chronic kidney
disease (CKD) patients with symptoms of MI (regardless of the severity of
renal impairment). Dynamic changes in troponin values of ≥20% over
6-9 h should be used to define acute MI in end-stage renal disease (ESRD)
patients.
ÎÎIn the absence of specific interventions based on the results, routine
troponin testing is NOT recommended for nonischemic clinical conditions
except:
• FDA-approved troponin testing for prognosis in CKD patients.
• Treatment of patients undergoing chemotherapy who have drug-induced cardiac injury.
ÎÎTroponin elevation is associated with a worse prognosis, irrespective of the
underlying etiology.
ÎÎFor patients with non–ST-segment elevation acute coronary syndrome
(ACS), global risk assessment rather than any single risk marker best
informs prognosis and is preferred to guide therapeutic decisions.
ÎÎThe major challenge of troponin testing in clinical practice, as for any
other laboratory test, is often an inappropriate request and improper
interpretation of the results, not the marker itself.
When to Perform Troponin Testing
ÎÎTroponin evaluation should be performed only if clinically indicated.
Elevated troponin must always be interpreted in the context of the clinical
presentation. Only by doing so will troponin evaluation allow for optimal
interpretation, diagnosis, risk stratification, and patient management.
