Troponin

Troponin is a protein of key importance in the functioning of skeletal and cardiac muscle. It forms part of the contractile mechanism, and comprises three main subunits: troponin C, troponin I, and troponin T.

Troponin elevation

Elevation of serum troponin can occur from a number of causes and it is useful for the radiologist to have a basic understanding of this, especially when interpreting imaging findings in the context of hypertroponinemia.

Etiology

The list includes:

• cardiac causes
  • acute myocardial infarction
  • post cardiac surgery: open heart surgery, cardiac transplantation
  • following certain cardiac procedures
    • percutaneous coronary intervention (PCI)
    • high frequency ablation
    • external current cardioversion
    • defibrillator shocks
  • cardiac failure
    • acute cardiac failure
    • chronic cardiac failure
  • acute myocarditis
  • acute pericarditis 
  • cardiotoxic chemotherapy
  • direct cardiac trauma: myocardial contusion
  • cardiac infiltrative conditions
    • cardiac amyloidosis
  • takotsubo cardiomyopathy
• non-cardiac causes
  • systemic inflammatory response syndrome (SIRS)
    • etiologies including viral infections, e.g. COVID-19
  • septic shock
  • pulmonary embolism: may be elevated in up to half of cases
  • strenuous exercise
  • renal failure
    • end stage renal failure
  • strokes
    • subarachnoid hemorrhage (SAH)
  • chronic obstructive pulmonary disease (COPD)