Troponin
A serum troponin level is something that is checked by the ER, not to rule out active cardiac ischemia but to guarantee admission. A troponin should be checked in a patient whose troponin level shouldn't be checked (i.e. foot pain). As it is ultimately going to be slightly positive, it is a quick and dirty way to get a patient transitioned to the inpatient setting. When checking a troponin, the main etiologies of concern are STEMI and NSTEMI. However, there are numerous other causes of an elevated troponin and they encompass both the significant (sympathomimetic use, recent chest trauma, demand ischemia from sepsis or arrhythmia, and renal failure) and the insignificant (yawning, one cough, thinking, chewing, working,[1] and waving hello).
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