Myocardial infarction occurs when:

Myocardial infarction, commonly known as a heart attack, is primarily characterized by damage to the heart muscle due to a significant reduction or complete cessation of blood flow, which is typically caused by a blockage in a coronary artery. When blood flow is restricted, the heart muscle does not receive sufficient oxygen, leading to ischemia and subsequent necrosis (death) of the heart tissue. This process results in the muscle being classified as "dead" due to the lack of necessary oxygen and nutrients required for its survival and function.

While the concept of the heart muscle being dead due to lack of oxygen is integral to understanding myocardial infarction, it is crucial to note that the initial event leading to this condition is often the blockage of a coronary artery. The oxygen deprivation itself is a critical event that ultimately results in a section of the heart muscle dying.

Recognizing these pathological processes allows for better insight into the critical nature of timely medical interventions during a myocardial infarction to restore blood flow and potentially salvage heart muscle that is still viable but at risk of dying due to insufficient oxygen.