DIFFERENTIATING EXERCISE-INDUCED CARDIAC BIOMARKER ELEVATION FROM ACUTE CORONARY SYNDROME: A LITERATURE REVIEW ON RELEASE KINETICS AND WASHOUT DURATION

Background: Cardiac troponin elevation after strenuous exercise can mimic the biochemical profile of acute coronary syndrome (ACS), risking misdiagnosis in athletes and active individuals presenting to the emergency department. This review synthesises 31 sources to establish an evidence base on release kinetics and washout duration of cardiac biomarkers after exercise relative to ACS.
Methods: A narrative synthesis was performed on publications from Circulation, the Journal of the American College of Cardiology, the European Heart Journal, Clinical Chemistry, the Journal of the American Heart Association, the American Journal of Physiology, and BMJ Open Sport & Exercise Medicine, focusing on release mechanisms, modifying factors, differential diagnosis, and clinical management.
Results: Troponin elevation above the 99th-percentile upper reference limit (URL) was observed in approximately 36% of individuals after exercise overall, rising to 57–93% with high-sensitivity assays after endurance exercise lasting 3–6 hours. The kinetic pattern is characteristic: concentrations peak at 2–6 hours and return toward baseline within 24–72 hours, contrasting with ACS, which peaks at 10–24 hours and remains elevated for 4–10 days. Cardiovascular magnetic resonance evidence consistently shows no late gadolinium enhancement after exercise, supporting reversible membrane leakage rather than irreversible necrosis. The relationship between post-exercise troponin elevation and subclinical coronary artery disease remains inconsistent across studies.
Conclusion: Differentiating exercise-induced biomarker elevation from ACS requires integrating clinical history, electrocardiography, serial kinetic patterns, and imaging, rather than a single value above the URL. Athlete-specific reference values, standardised sampling protocols, and long-term cohort studies remain key research gaps.