Unstable angina is a condition in which your heart doesn't get enough blood flow and oxygen. It may lead to a heart attack.
Angina is a type of chest discomfort caused by poor blood flow through the blood vessels (coronary vessels) of the heart muscle (myocardium).
Coronary artery disease due to atherosclerosis is by far 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 increased risk of having a heart attack.
Rare causes of angina are:
Risk factors for coronary artery disease include:
Symptoms of angina may include:
With stable angina, the chest pain or other symptom only occurs with a certain amount of activity or stress. The pain does not occur more often or get worse over time.
Unstable angina is chest pain that is sudden and often gets worse over time. You may be developing unstable angina if the chest pain:
Unstable angina is a warning sign that a heart attack may happen soon. It needs to be treated right away. If you have any type of chest pain, see your doctor.
The doctor will perform a physical examination and check your blood pressure. The doctor may hear abnormal sounds, such as a heart murmur or irregular heartbeat, when listening to your chest with a stethoscope.
Tests for angina include:
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, unless they would be unsafe for you to take. These medicines include aspirin and the prescription drug clopidogrel. Aspirin (and sometimes clopidogrel) may reduce the chance of a heart attack in certain patients.
During an unstable angina event:
Often if a blood vessel is found to be narrowed or blocked, a procedure called angioplasty and stenting can be done to open the artery.
Heart bypass surgery may be done for some people. Whether this surgery is done depends on which arteries, how many arteries, and what parts of their coronary arteries are narrowed, and how severe the narrowings are.
Unstable angina is a sign of more severe heart disease.
How well you do depends on many different things, including:
Abnormal heart rhythms and heart attacks can cause sudden death.
Unstable angina may lead to:
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:
Call your doctor if:
If you think you are having a heart attack, get medical treatment right away.
Lifestyle changes can help prevent some angina attacks. Your doctor may tell you to:
Also keep strict control of your blood pressure, diabetes, and cholesterol levels. Some studies have shown that making a few lifestyle changes can prevent blockages from getting worse and may actually improve them.
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 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.
Accelerating angina; New-onset angina; Angina - unstable; Progressive angina
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Lange RA, Hillis LD. Acute coronary syndrome: unstable angina and non-ST elevation myocardial infarction. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 72.
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.
Wright RS, Anderson JL, Adams CD, et al. ACCF/AHA Focused Update of the Guidelines for the Management of Patients with Unstable Angina/Non-ST-Elevation Myocardial Infarction (Updating the 2007 Guideline) A Report of the American College of Cardiology Foundation/American Heart Association Task Force on Practice Guidelines Developed in Collaboration With the American College of Emergency Physicians Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. J Am Coll Cardiol. 2011;57:1920-1959
Updated by: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Michael A. Chen, MD, PhD, Assistant Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.
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