Ischemic heart disease is what happens when the heart is deprived of oxygen. When this happens, one of the ways it manifests is known as angina. Coronary blood vessels supply blood, along with nutrients and oxygen, to the heart. Angina occurs when there is significant narrowing or obstruction of the walls of the coronary blood vessels, which happens due to several causes. According to the National Heart Lung and Blood Institute, there are about 7 million people who suffer from angina in the United States.There are three types of angina: stable angina, Prinzmetal's variant and unstable angina.
Stable Angina
Stable angina is the most common form of angina. It usually happens when there is narrowing or obstruction in the coronary blood vessels, which can be due to fat deposition, smoking, hypertension or diabetes. It can also be seen in the elderly, where more force is needed to eject blood from the left side of the heart to the rest of the body. It causes a decreased blood flow, which is only evident after strenuous activity, such as exercise. There is usually chest pain felt behind the breast bone that lasts from 30 seconds to about 30 minutes. This pain can be relieved by resting or by taking medication known as nitrates, which help relax the blood vessels.
Prinzmetal's Angina
Prinzmetal's angina happens between midnight and the early morning hours, and it also occurs at rest, even without evidence of strenuous activity. There is a spasm of the coronary artery, which results in decreased blood flow to the heart. Prinzmetal's angina can be treated with nitrates or calcium channel blockers, both of which are medications that relax the coronary artery.
Unstable Angina
Unstable angina, unlike stable angina, is unpredictable and does not have a regular pattern. It happens due to severe blockage in the coronary arteries, which is caused by a rupture of fatty materials, known as plaque, from the walls of the coronary arteries. It can happen at any time, either during exercise or at rest. There are frequent bouts of chest pain that are not relieved by rest or medication. Unstable angina can easily progress to a heart attack and is considered to be an emergency situation.
