Associations between High Sensitivity Troponin in the Emergency Department and Diagnosis of Myocarditis

Background: The diagnosis of myocarditis is challenging, and typically relies on clinical presentation, non-invasive imaging, and serum biomarkers. We examine if implementation of hsTnT has affected recognition of myocarditis and patient outcomes. Methods: Retrospective analysis of >18-year-old patients diagnosed with myocarditis in Meir Medical Center since January 2000 to the end of April 2020. Patients were divided based on their diagnosis date - up to January 2014, for which there was a regular troponin test (REG group) and starting February 2014 for which there was a hsTnT test (HS group). We examined the difference in the rate of myocarditis diagnosis, mortality, and hospitalizations due to heart failure. Results: We identified 262 patients who were diagnosed with myocarditis. There were no significant differences between the groups. After the implementation of hsTnT there was a two-fold increase in the diagnosis rate (0.0366 vs. 0.0625 cases per day; P<0.0001). The REG group presented with more ST changes (51% vs. 29%; p=0.006) and less cases of normal heart function (69% vs. 79%; P=0.048). There was a higher mortality rate in HS group (6 deaths vs. 2; p=0.011). Conclusions: hsTnT test leads to increase in myocarditis diagnosis and allows for diagnosing more mild case.