Angina pectoris is the medical term for chest pain or discomfort due to coronary heart disease. Angina is a symptom of a condition called myocardial ischemia. It occurs when the heart muscle (myocardium) doesn't get as much blood (hence as much oxygen) as it needs. This usually happens because one or more of the heart's arteries (blood vessels that supply blood to the heart muscle) is narrowed or blocked. Insufficient blood supply is called ischemia.
Angina also can occur in people with valvular heart disease, hypertrophic cardiomyopathy (this is an enlarged heart due to disease) or uncontrolled high blood pressure. These cases are rare, though.
Typical angina is uncomfortable pressure, fullness, squeezing or pain in the center of the chest. The discomfort also may be felt in the neck, jaw, shoulder, back or arm. Many types of chest discomfort aren't related to angina. Acid reflux (heartburn) and lung infection or inflammation are examples.
In people with unstable angina, the chest pain is unexpected and usually occurs while at rest. The discomfort may be more severe and prolonged than typical angina or be the first time a person has angina. The most common cause is reduced blood flow to the heart muscle because the coronary arteries are narrowed by fatty buildups (atherosclerosis). An artery may be abnormally constricted or partially blocked by a blood clot. Inflammation, infection and secondary causes also can lead to unstable angina. In a form of unstable angina called variant or Prinzmetal's angina, the cause is coronary artery spasm. |
