What is angina?

Angina is pain or discomfort that comes when your heart does not get enough oxygen. Angina is most often a symptom of a heart problem known as coronary heart disease (CHD), also called coronary artery disease (CAD).²

Your heart is a muscle. It pumps oxygen-rich blood to your whole body. Your heart also needs oxygen to work. Blood vessels called coronary arteries carry blood with oxygen to your heart. These arteries are on the surface of your heart.^2,3

In healthy coronary arteries, blood flows freely to bring oxygen to the heart. In coronary heart disease, these arteries become stiff and narrow. This lowers blood flow and the amount of oxygen that gets to the heart. With exercise or emotional stress, the heart works harder and needs more oxygen. Lower blood flow can lead to angina. You could feel discomfort or pain in the chest, arm, shoulder, back, neck or jaw. When angina has been present for months or years without much change, it is called chronic stable angina. It most often goes away with rest or nitroglycerin*.^2,3

If a clot forms in a coronary artery, it can further block blood flow. This can lead to chest pain known as unstable angina. It most often occurs at rest. Unstable angina is a medical emergency and requires medical help right away.^2,3

In summary, when blood flow is reduced, your heart does not get as much oxygen as it needs. It cannot pump blood like it should. This lack of oxygen can cause the pain and discomfort of angina. If you have coronary heart disease, angina is the way your heart tells you it needs more oxygen.^2,3

Types of angina

There are three types of angina:^2,3

• Chronic angina
• Chronic angina can occur during physical activity or emotional stress. These are times when the heart is working harder. An episode of chronic angina usually lasts five minutes or less. Certain activities can trigger angina. People usually know what things will cause them to have angina.
  • Common triggers: physical activity such as climbing stairs or lifting heavy objects; emotional stress; extreme heat or cold; eating large meals; smoking
  • Relieved by: resting or nitroglycerin*
    
    
• Unstable angina
• Unstable angina happens with or without physical activity — even while you are at rest or sleeping. If you have unstable angina, you could be at risk of a heart attack. If you have pain that is getting worse or does not go away with rest or nitroglycerin, you could be having a heart attack. You should get emergency medical help right away. In this type of angina, you cannot tell what will trigger an attack. Unstable angina is more severe and usually lasts as long as 30 minutes.
  • No common triggers: can occur with little or no physical activity; at rest or while sleeping
  • Relieved by: nothing reliably relieves unstable angina. You should get emergency medical help right away.
    
    
• Variant angina
• Variant angina is a rare type of angina. It happens without warning. The pain is caused by sudden tightening or spasm of a coronary artery. It most often happens at rest, between midnight and early morning. The pain can be severe. With this type of angina, your heart rhythm can become dangerously abnormal.
  • No common triggers: occurs while at rest or sleeping
  • Relieved by: medicine; seek medical attention immediately