cTnI (troponin)

Rapid CDIA^TM cTnI kits are intended for the diagnosis of heart

The 3-unit troponin complex (troponin I, T and C) is located on the actin filament and is essential for the calcium-mediated regulation of skeletal and cardiac muscle contraction. Troponin T binds the troponin complex to tropomyosin. Troponin I inhibits actomyosin ATPase. Troponin C contains four binding sites for Ca2+ that helps initiate contraction. Both Troponin T and Troponin I have specific isoforms in cardiac tissue. These proteins are released when the heart muscle has been damaged, such as occurs with a heart attack. Troponin is more specific for heart injury than other tests and remains elevated for a longer period of time. Increased troponin levels should not be used by themselves to diagnose or rule out a heart attack. A physical exam, clinical history, and ECG are also important. Elevated cTn without clinical evidence of ACS should prompt a search for other possible myocardial injuries.