Myocardial ischemia (also known as angina) is a heart condition caused by a temporary lack of oxygen-rich blood to the heart. There are three types, each of which is signified by pain. The stable type occurs when the heart is working harder than usual and generally goes away with rest; unstable myocardial ischemia is dangerous and requires emergency treatment; variant (also called Prinzmetal's angina) occurs at rest and can be relieved by medicine.
More than 6 million Americans live with myocardial ischemia, or angina. The term refers to chest pain or discomfort that occurs when the heart muscle is not getting enough oxygen-rich blood for a short period of time. The inadequate blood flow is caused by narrowed coronary arteries, which are the vessels that supply blood to the heart. A bout of myocardial ischemia is not a heart attack, but it means that you're more likely to have a heart attack than someone who doesn't have myocardial ischemia.
In order to understand the cause of myocardial ischemia, it is often helpful to understand the heart and the coronary arteries. Like any muscle, the heart needs a constant supply of oxygen and nutrients, which are carried to it by the blood in the coronary arteries. Similar to other muscles, the harder the heart is working, the more oxygen and nutrients it needs. However, the coronary arteries can become narrowed or clogged, which can decrease the amount of blood that goes to the heart muscle. When the coronary arteries cannot supply enough oxygen-rich blood to the heart, symptoms of myocardial ischemia can occur.
There are three types of myocardial ischemia:
- Variant (also known as Prinzmetal's angina).
Stable Myocardial Ischemia
Stable myocardial ischemia is the most common type. It occurs when the heart is working harder than usual. There is a regular pattern to this condition. After several episodes, you learn to recognize the pattern and can predict when it will occur. The pain usually goes away in a few minutes after you rest or take your medicine.