Why does angina occur?

As a medical professional with expertise in cardiology, I can explain that angina pectoris is a condition that manifests as chest pain or discomfort, typically arising from coronary heart disease. Angina occurs when the heart muscle is not receiving an adequate supply of blood. This is often due to the narrowing or blockage of one or more of the arteries that supply the heart, a condition known as ischemia. The blockage can be caused by a buildup of fatty deposits, or plaque, within the coronary arteries, a process known as atherosclerosis. When these plaques rupture, they can cause blood clots to form, which further restrict blood flow. The reduced blood flow means that the heart muscle does not get the necessary oxygen and nutrients it needs to function properly, leading to the pain characteristic of angina. Angina can be classified into two main types: stable angina and unstable angina. Stable angina is predictable and usually occurs during physical exertion or emotional stress when the heart's demand for oxygen increases. Unstable angina, on the other hand, can occur at rest or with minimal exertion, and it is considered a more serious form that may precede a heart attack.

Angina pectoris is the medical term for chest pain or discomfort due to coronary heart disease. It occurs when the heart muscle doesn't get as much blood as it needs. This usually happens because one or more of the heart's arteries is narrowed or blocked, also called ischemia.