When does angina pectoris turn into a myocardial infarction?

Angina pectoris refers to chest pain or discomfort due to inadequate blood supply (and thus oxygen) to the heart muscle, typically during physical exertion or emotional stress. It is a signal that the heart is not receiving enough oxygen to meet its demands but does not usually result in permanent damage if the oxygen supply is restored.

The transition from angina pectoris to a myocardial infarction occurs when the heart is deprived of oxygen for an extended period, leading to irreversible damage to the heart muscle. If a blockage, such as that caused by a blood clot, restricts blood flow to a part of the heart for too long, the muscle cells begin to die due to oxygen deprivation, culminating in a heart attack (myocardial infarction). This underlines the necessity of prompt treatment for angina, as it can escalate to a more serious condition when the oxygen supply is not restored.

In contrast, while excessive exercise, a sudden drop in blood pressure, or severe anxiety can exacerbate the circumstances surrounding cardiovascular issues, they do not directly cause the shift from angina pectoris to myocardial infarction in the same definitive way that prolonged oxygen deprivation does.