Coronary artery disease due to atherosclerosis is the most common cause of unstable angina. Atherosclerosis is the buildup of fatty material, called plaque, along the walls of the arteries. This causes arteries to become narrowed and less flexible. The narrowing interrupts blood flow to the heart, causing chest pain.
People with unstable angina are at higher risk of having a heart attack.
Coronary angiography. This test involves taking pictures of the heart arteries using x-rays and dye. It is the most direct test to diagnose heart artery narrowing and find clots
Your doctor may want you to check into the hospital to get some rest, have more tests, and prevent complications.
Blood thinners (antiplatelet drugs) are used to treat and prevent unstable angina. You will receive these drugs as soon as possible if you can take them safely. Medicines include aspirin and the prescription drug clopidogrel or something similar. These medicines may be able to reduce the chance of a heart attack or the severity of a heart attack that occurs.
During an unstable angina event:
You may get heparin (or another blood thinner) and nitroglycerin (under the tongue or through an IV)
Other treatments may include medicines to control blood pressure, anxiety, abnormal heart rhythms, and cholesterol (such as a statin drug)
A procedure called angioplasty and stenting can often be done to open a blocked or narrowed artery
Angioplasty is a procedure to open narrowed or blocked blood vessels that supply blood to the heart.
A coronary artery stent is a small, metal mesh tube that opens up (expands) inside a coronary artery. A stent is often placed after angioplasty. It helps prevent the artery from closing up again. A drug-eluting stent has medicine in it that helps prevent the artery from closing.
Unstable angina is a sign of more severe heart disease.
How well you do depends on many different things, including:
How many and which arteries in your heart are blocked, and how severe the blockage is
If you have ever had a heart attack
How well your heart muscle is able to pump blood out to your body
Abnormal heart rhythms and heart attacks can cause sudden death.
Unstable angina may lead to:
Abnormal heart rhythms (arrhythmias)
A heart attack
When to Contact a Medical Professional
Seek medical attention if you have new, unexplained chest pain or pressure. If you have had angina before, call your doctor.
Call 911 if your angina pain:
Is not better 5 minutes after you take nitroglycerin (your health care provider may tell you to take three total doses)
Does not go away after three doses of nitroglycerin
Is getting worse
Returns after the nitroglycerin helped at first
Call your doctor if:
You are having angina symptoms more often
You are having angina when you are sitting (rest angina)
You are feeling tired more often
You are feeling faint or light-headed, or you pass out
Your heart is beating very slowly (less than 60 beats a minute) or very fast (more than 120 beats a minute), or it is not steady
You are having trouble taking your heart medicines
You have any other unusual symptoms
If you think you are having a heart attack, get medical treatment right away.
Some studies have shown that making a few lifestyle changes can prevent blockages from getting worse and may actually improve them. Lifestyle changes can also help prevent some angina attacks. Your doctor may tell you to:
Lose weight if you are overweight.
Drink alcohol in moderation only.
Eat a healthy diet that is high in vegetables, fruits, whole grains, fish, and lean meats.
Your doctor will also recommend that you keep other health conditions such as high blood pressure, diabetes, and high cholesterol levels under control.
If you have one or more risk factors for heart disease, talk to your doctor about taking aspirin or other medicines to help prevent a heart attack. Aspirin therapy (75 - 325 mg a day) or drugs such as clopidogrel, ticagrelor or prasugrel may help prevent heart attacks in some people. Aspirin therapy is recommended if the benefit is likely to outweigh the risk of side effects.
Cannon CP, Braunwald E. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, PA: Saunders Elsevier; 2011:chap 56.
Montalescot G, Cayla G, Collet JP, Elhadad S, Beyqui F, Le Breton H, et al. Immediate vs. delayed intervention for acute coronary syndromes: a randomized clinical trial. JAMA. 2009;302:947-954.
Anderson JL, Adams CD, Antman EM, et al. 2012 ACCF/AHA focused update incorporated into the ACCF/AHA 2007 guidelines for the management of patients with unstable angina/non-ST-elevation myocardial infarction. J Am Coll Cardiol. 2013;61(23):e179-347.
Michael A. Chen, MD, PhD, Associate Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.