Angina

Angina - or angina pectoris (Latin for squeezing of the chest) - is chest pain, discomfort, or tightness that occurs when an area of the heart muscle is receiving decreased blood oxygen supply. It is not a disease itself, but rather a symptom of coronary artery disease, the most common type of heart disease. The lack of oxygen rich blood to the heart is usually a result of narrower coronary arteries due to plaque buildup, a condition called atherosclerosis. Narrow arteries increase the risk of pain, coronary artery disease, heart attack, and death.

Angina may manifest itself in the form of an angina attack, pain or discomfort in the chest that typically lasts from 1 to 15 minutes. The condition is classified by the pattern of attacks into stable, unstable, and variant angina.
  * Stable (or chronic) angina is brought on when the heart is working harder than usual, such as during exercise. It has a regular pattern and can be predicted to happen over months or even years. Symptoms are relieved by rest or medication.

  * Unstable angina does not follow a regular pattern. It can occur when at rest and is considered less common and more serious as it is not relieved by rest or medicine. This version can signal a future heart attack within a short time - hours or weeks.

  * Variant (Prinzmetal's) angina and microvascular (smallest vessels) angina are rare and can occur at rest without any underlying coronary artery disease. This angina is usually due to abnormal narrowing or relaxation (spasm) of the blood vessels, reducing blood flow to the heart. It is relieved by medicine.
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