Troponin I test is an important blood test that can help you detect a heart attack. Usually, troponin remains within the cells of the heart muscle. However, damage to these cells, such as that caused by a heart attack, leads to the leakage of troponin into the bloodstream. As the damage to the heart progresses, larger quantities of troponin can be detected. In cases where a heart attack is suspected, doctors often perform multiple troponin-level tests within 24 hours. These tests may also be conducted to assess heart injury resulting from specific medical procedures. Higher levels of troponin in the blood indicate more extensive heart damage, which helps assist doctors in determining the severity of a heart attack.