A person who’s diagnosed with a heart attack in the ER based on an elevated troponin result may not have had a heart attack after all.
The European Heart Journal has a 2018 study (Thygesen et al) that says “many doctors have not understood that elevated troponin levels in the blood are not sufficient to diagnose a heart attack.”
The paper explains that a heart attack causes injury to cardiac muscle. The protein troponin is used for cardiac muscle contraction.
But it’s released into the bloodstream upon injury to that specialized muscle.
A highly sensitive blood test will tell if there’s even the must subtle rise in troponin.
The reason that an abnormal level of troponin doesn’t always mean a heart attack is because there are other situations that injure cardiac muscle.
• Infection, sepsis
• Kidney disease
• Heart surgery
• Strenuous exercise – such as CrossFit training
Correct identification for the reason of a rising troponin level is crucial because even different types of ischemia to the heart have different causes. Different causes mean different treatments.
One type might require antiplatelet drugs, while another treatment (for a different cause) may require beta blocker drugs.
Currently, the International Classification of Diseases (ICD) does not have diagnosis codes for the subtypes of heart attack.
“The incorporation of type 2 [heart attack] into the ICD codes is another step towards accurate recognition followed by appropriate treatment,” states the paper. “A code for myocardial injury will be added to the ICD next year.”