Troponin is a regulatory protein complex found in cardiac and skeletal muscle fibres that controls muscle contraction by modulating the interaction between actin and myosin in response to calcium levels. Clinically, measurement of cardiac-specific troponin isoforms is essential for diagnosing myocardial injury, particularly acute myocardial infarction. Elevated troponin levels indicate cardiac muscle damage and are crucial for guiding timely treatment and risk stratification in patients with suspected acute coronary syndromes.