Angina is usually a sign of coronary artery disease (CAD). It happens when the blood vessels leading to the heart are narrowed or blocked. The blockage decreases blood and oxygen flow to the heart. The lack of oxygen results in chest pain and other symptoms.

Coronary Artery Disease
Coronary Artery plaque
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Stable or Unstable Angina

Angina happens when the heart's need for blood and oxygen is increased by:

  • Exercise or exertion
  • Cold weather
  • A large meal
  • Emotional stress

Stable angina becomes unstable when symptoms:

  • Happen more often
  • Last longer
  • Are triggered more easily

Variant or Prinzmetal Angina

This type of angina is usually caused by a spasm of a heart vessel. It may be a sign of:

  • CAD
  • Extremely high blood pressure
  • Hypertrophic cardiomyopathy
  • Diseases of the heart valves

Risk Factors

CAD is more common in older men. Other things that may raise the risk of CAD include:

  • Strong family history of heart disease
  • Obesity and overweight
  • Smoking
  • High blood pressure
  • Sedentary lifestyle
  • High blood cholesterol—specifically:
  • High low-density lipoprotein (LDL) cholesterol, and
  • Low high-density lipoprotein (HDL) cholesterol
  • Diabetes
  • Stress
  • Excessive alcohol intake



Symptoms may include:

  • Pressure or squeezing chest pain
    • Chest pain or discomfort is the key symptom of angina
    • Some people do not have the pain as badly
    • Older people, women, and people with diabetes are more apt to have milder symptoms and pain in other areas
    • Some people have silent ischemia (lack of blood supply to the heart) and do not have chest pain

A heart attack is more likely when chest discomfort is severe, lasts more than 15 minutes, and there are symptoms, such as:

  • Pain in the shoulder(s) or arm(s), or into the jaw(s)
  • Weakness
  • Sweating
  • Nausea
  • Shortness of breath


The doctor will ask about symptoms and personal and family health. Tests will be done right away. The tests will see if the person is having angina or a heart attack. Some tests may be used to rule out other causes.

For stable patterns of angina, other tests may be done. These tests will check the extent of disease. That way it can be properly treated.

Images may be taken of the heart with:

  • Echocardiogram
  • Nuclear scanning
  • Electron-beam CT scan (coronary calcium scan, heart scan, CT angiography)
    • Heart scans are not for everyone. They are more likely to benefit those with an average risk of CAD.
  • Coronary angiography

Heart activity may be tested with:

  • Electrocardiogram (ECG)
  • Exercise stress test
    • Some people cannot exercise. To take this test, they will need a special medicine during the test. The medicine will create the effect of physical activity.



Treatment will help to improve blood flow to the heart. Some may be longer acting. Others may be used when an attack happens. Treatment may include:


Medicine may be given to:

  • Stop an angina attack—May be taken as a pill that dissolves under the tongue or as a spray.
  • Prevent angina before activity—May be taken as pills or applied as patches or ointments.
  • Thin the blood—To decrease the risk of heart attack.
  • Reduce the number of angina attacks.
  • Lower cholesterol—May prevent CAD from getting worse; or may even improve existing CAD.
  • Lower blood pressure and decrease the workload on the heart.
  • Treat long term angina.


Some people have severe angina or unstable, worsening angina. If so, the doctor may advise:

  • Coronary artery bypass graft—Uses arteries from other areas of the body to bypass blocked heart arteries.
  • Coronary angioplasty—Uses a balloon to open blocked arteries.


Steps to prevent CAD include:

  • Maintain a healthy weight.
  • Begin a safe exercise program with the advice of your doctor.
  • Do not smoke or vape.
  • Eat a healthy diet that is:
  • Low in saturated fat
  • Rich in whole grains, fruits, and vegetables
  • Manage high blood pressure and diabetes.
  • Manage abnormal cholesterol levels or high triglycerides.

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.

Edits to original content made by Denver Health.