What is angina?

Angina is usually a symptom of a serious condition called coronary heart disease (CHD), also known as coronary artery disease (CAD).²

The heart's job is to pump oxygen-rich blood throughout your body. To do its job, the heart needs a steady supply of blood. The vessels that supply blood to your heart are called coronary arteries. These very important vessels are located on your heart.^2,3

In a healthy heart, blood flows freely through the coronary arteries providing the heart with the oxygen it needs. In coronary heart disease, the vessels may become stiff and narrow making it difficult for oxygen-rich blood to reach your heart. Reduced blood flow that occurs following exercise or emotional stress can lead to discomfort or pain in the chest or surrounding areas (arm, shoulder, back, neck or jaw) known as chronic stable angina, which is often relieved by rest or nitroglycerin.^2,3

If a clot develops in the coronary artery, blood flow may be reduced more severely. This can lead to chest pain known as unstable angina, which usually occurs at rest and it requires immediate medical attention.^2,3

In summary, when blood flow is reduced, your heart does not get as much oxygen as it needs so 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 your heart’s way of telling you that it needs more oxygen.^2,3

Types of angina

There are three types of angina:^2,3

• Chronic angina
• Chronic angina occurs during physical activity or emotional stress because the heart is working harder during those times, than when the body is at rest. Because chronic angina is triggered by activity, this type of angina is often predictable. Chronic angina usually lasts a short time of five minutes or less.
  • Common triggers: physical activity such as climbing stairs or lifting heavy objects; emotional stress; exposure to extreme temperatures; eating large meals; smoking
  • Relieved by: resting or nitroglycerin*
    
    
• Unstable angina
• Unstable angina happens with or without physical activity — sometimes while at rest or sleeping. Unstable angina means you are at immediate risk of a heart attack and should seek emergency help. This type of angina is unpredictable, 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; seek medical attention immediately
    
    
• Variant angina
• Variant angina is a rare type of angina. This type of angina occurs without warning. It is caused by sudden tightening of a coronary artery. It usually occurs while at rest, between midnight and early morning. During an episode of variant angina, the pain can be severe and there can be disruptions in your heart's rhythm.
  • No common triggers: occurs while at rest or sleeping
  • Relieved by: medicine; seek medical attention immediately

Learn about what angina feels like