Angina

Summary
Angina is chest pain or discomfort you feel when there is not enough blood flow to your heart muscle. Your heart muscle needs the oxygen that the blood carries. Angina may feel like pressure or a squeezing pain in your chest. It may feel like indigestion. You may also feel pain in your shoulders, arms, neck, jaw, or back.

Angina is a symptom of coronary artery disease (CAD), the most common heart disease. CAD happens when a sticky substance called plaque builds up in the arteries that supply blood to the heart, reducing blood flow.

There are three types of angina:

Stable angina is the most common type. It happens when the heart is working harder than usual. Stable angina has a regular pattern. Rest and medicines usually help.
Unstable angina is the most dangerous. It does not follow a pattern and can happen without physical exertion. It does not go away with rest or medicine. It is a sign that you could have a heart attack soon.
Variant angina is rare. It happens when you are resting. Medicines can help.
Not all chest pain or discomfort is angina. If you have chest pain, you should see your health care provider.

NIH: National Heart, Lung, and Blood Institute

Start Here
Angina (American Academy of Family Physicians)
Also in Spanish
Angina (Mayo Foundation for Medical Education and Research)
Angina From the National Institutes of Health (National Heart, Lung, and Blood Institute)
Also in Spanish
Angina (Chest Pain) (American Heart Association)
Also in Spanish
Angina Pectoris (Stable Angina) (American Heart Association)
Diagnosis and Tests
Chest Pain (Mayo Foundation for Medical Education and Research)
Also in Spanish
CK-MB Test (American Association for Clinical Chemistry)
Heart Health Tests: MedlinePlus Health Topic From the National Institutes of Health (National Library of Medicine)
Also in Spanish
Radionuclide Ventriculography or Radionuclide Angiography (MUGA Scan) (American Heart Association)
Troponins Test (American Association for Clinical Chemistry)
Prevention and Risk Factors
Who Is at Risk for Angina? From the National Institutes of Health (National Heart, Lung, and Blood Institute)
Treatments and Therapies
Angina Treatment -- Medical Versus Interventional Therapy (Beyond the Basics) (UpToDate)
Angina Treatment: Stents, Drugs, Lifestyle Changes -- What's Best? (Mayo Foundation for Medical Education and Research)
Also in Spanish
Calcium Channel Blockers (Mayo Foundation for Medical Education and Research)
Also in Spanish
Medications for Angina (Beyond the Basics) (UpToDate)
Nitrates (Texas Heart Institute)
Also in Spanish
Transmyocardial Laser Revascularization (Texas Heart Institute)
Also in Spanish
Specifics
Acute Coronary Syndrome (American Heart Association)
Microvascular Angina (American Heart Association)
Prinzmetal's Angina, Variant Angina and Angina Inversa (American Heart Association)
Unstable Angina (American Heart Association)
What Is a Coronary Artery Spasm? (Mayo Foundation for Medical Education and Research)