The cytoplasm of heart cells comprises of free and bound forms of troponin. Troponin consists of three protein subunits: troponin T, troponin I, and troponin C.
In the initial stage of the damage to the heart, the free troponin T is released in the blood. The bound troponin T is released at a later stage-matching the myofibrils degradation happening duringirreversible myocardial damage. Two to three hours after the onset of myocardial myofibrils destruction or necrosis, the levels of troponin elevate and remain elevated for up to 15 days. A troponin T test measures the levels of troponin in the blood.
Why is the test ordered?
A troponin test is used as a marker of choice for assessing individuals with a possible cardiac injury. The test may be helpful in the diagnosis of heart attack and to rule out other conditions. The test may also help in monitoring acute coronary syndrome and individuals with a non-ischemic cardiac injury.
When is the test ordered?
The test is mainly prescribed to ensure if a heart attack has occurred when a person complains of chest pain with other signs of heart attack. The test may also be recommended ifa person has angina which is getting worse and to detect and assess other causes of heart injury. The test may also be recommended along with other tests like myoglobin or CPK.
How is the sample collected?
A blood sample is drawn from a vein in the arm.
How to prepare for the test?
No special preparation is required for the test.