Final answer:
Cardiac markers relevant to a myocardial infarction include creatine kinase MB (CK-MB), cardiac troponin, and the LDH1 form of lactate dehydrogenase. These substances are released into the blood when cardiac muscle cells are damaged.
Step-by-step explanation:
Cardiac markers are specific substances released into the bloodstream when the heart is damaged or stressed.
Characteristic markers that are released during a myocardial infarction (MI), commonly known as a heart attack, include creatine kinase MB (CK-MB), cardiac troponin, and certain isoenzymes of lactate dehydrogenase (LDH), especially the LDH1 isoenzyme form.
CK-MB is an enzyme involved in energy production in cells and is one of the first markers to show elevated levels in the blood following an MI. The elevation happens within a few hours and peaks at 18-24 hours, making it a valuable early indicator of MI.
Cardiac troponin, which is a protein that helps control muscular contractions, remains elevated for an extended period of up to 7-10 days; thus, it is especially useful for diagnosing MI after the onset of symptoms.
Lastly, LDH1 increases in concentration in the plasma during myocardial infarction and its peak levels are maintained for about 6 days, providing another diagnostic tool for MI confirmation.
In addition to biochemical markers, an electrocardiogram (ECG) revealing alterations in the ST and Q components can be indicative of MI, classifying them into either ST-elevated MI (STEMI) or non-ST-elevated MI (non-STEMI).
Echocardiography and cardiac magnetic resonance imaging are also employed to assess heart structure and function after a suspected MI.