Troponin I (highly sensitive)
Why this test?
Most often a troponin I analysis is necessary to confirm or exclude a myocardial infarction in patients with acute heart pain or other symptoms. It is usually given along with other markers of heart muscle damage, such as creatine kinase MV and myoglobin. However, troponin I is the «gold standard» in the definition of a heart attack, as it is more specific than other indicators (which can increase even with skeletal muscle damage) and remains elevated for a long time.
In addition, this test is used to assess the degree of damage to the heart muscle, as well as to distinguish chest pain caused by non-cardiac causes. If a person feels pain or discomfort in the chest, as well as other symptoms associated with an exacerbation of coronary heart disease, and at the same time does not consult a doctor for several days, and troponin I is still elevated, then damage to the heart muscle is occurred.
In what cases is it prescribed?
This study is carried out when acute myocardial infarction is suspected. The analysis is carried out immediately when the patient enters the hospital and 6 and 12 hours after the first sample.
The troponin I assay is usually used in conjunction with other markers of myocardial damage, such as creatine kinase MV and myoglobin, to more accurately judge the presence or absence of acute myocardial damage.
This test is prescribed to patients with stable angina when the condition worsens, when symptoms occur at rest and / or do not decrease with treatment. Consequently, angina becomes unstable, which increases the risk of myocardial infarction.
A test for troponin I is also prescribed: if inflammation of the heart muscle tissue is suspected - myocarditis - and other diseases that cause damage to the myocardium,
before and after X-ray surgery (angioplasty and stenting) and cardiosurgery (coronary bypass surgery) on the heart to detect possible myocardial damage.
Troponins are proteins contained in skeletal muscles and heart muscle - myocardium. There are three types of troponin: troponin C, troponin I, and troponin T. Together, they are involved in muscle contraction. Troponin I and troponin T are found only in the heart muscle. These cardiospecific troponins (also referred to as cTnI and cTnT) are normally not found in the blood. When myocardial damage occurs, cardiac troponins I and T enter the bloodstream in large quantities. The amount of troponins that entered the bloodstream depends directly on the extent of myocardial damage.
The most sensitive and specific for damage to the heart muscle is troponin I. If a person has a myocardial infarction, that is, the death of a part of the heart muscle, the level of troponins in the blood rises 3-4 hours after the damage and can remain elevated for 10- 14 days.