What is a myocardial infarction (MI)?

A myocardial infarction (MI), commonly known as a heart attack, occurs when there is a blockage of blood supply to the heart muscle. This blockage is usually due to the buildup of fatty deposits, also known as plaques, within the coronary arteries. When these arteries become narrowed or completely blocked, the heart muscle does not receive the oxygen and nutrients it needs to function properly, leading to tissue damage or death.

The significance of timely intervention during an MI cannot be overstated; restoring blood flow is crucial to minimize heart muscle damage and improve patient outcomes. Recognizing the symptoms of an MI, such as chest pain, shortness of breath, and radiating discomfort to the arms or jaw, is vital for prompt medical attention.

Other options describe conditions related to the heart but do not accurately define a myocardial infarction. Malfunctions of heart valves affect blood flow through the heart but are different from the blockage that defines an MI. Electrical disturbances in heart rhythm relate to arrhythmias, while inflammation of the heart lining pertains to conditions like pericarditis. These distinctions clarify why the blockage of blood supply to the heart muscle is the correct definition of a myocardial infarction.