Final answer:
A suspected myocardial infarction (MI) can be confirmed by blood tests measuring levels of creatine kinase MB (CK-MB) and cardiac troponin, which are released into the blood in response to heart muscle damage.
Step-by-step explanation:
A suspected myocardial infarction (MI), commonly known as a heart attack, can be confirmed with various diagnostic tests. Blood tests are essential in confirming an MI, particularly when looking for elevated levels of certain enzymes and proteins. Two key substances tested in the blood that indicate an MI are creatine kinase MB (CK-MB) and cardiac troponin. CK-MB is an enzyme involved in energy production within the heart muscle and is released into the blood when cardiac muscle cells are damaged. Cardiac troponin, a regulatory protein for muscle contraction, also increases in the blood following damage to the heart muscle. Both of these are released into circulation soon after myocardial tissue damage occurs, and their elevated levels can confirm an MI. Additionally, an electrocardiogram (ECG) showing alterations in the ST and Q components can be indicative of an MI, with specific mention of ST-elevation MI (STEMI) and non-ST-elevation MI (non-STEMI), but this is supported and complemented by the mentioned blood tests.