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Home > Fitness & Health > Health Library > Acute Coronary Syndrome
Acute coronary syndrome happens when the heart is not getting enough blood. It is an emergency. It includes unstable angina and heart attack.
The coronary arteries supply oxygen-rich blood to the heart muscle. If these arteries are narrowed or blocked, the heart does not get enough oxygen. This can cause angina or a heart attack.
Any type of acute coronary syndrome is very serious and needs to be treated right away.
Acute coronary syndrome happens because blood flow has slowed or stopped in the arteries that supply blood to the heart. Acute coronary syndrome is typically caused by coronary artery disease. Coronary artery disease, also called heart disease, is caused by atherosclerosis, or hardening of the arteries.
Atherosclerosis causes a substance called plaque to build up in the coronary arteries. Plaque causes angina by narrowing the arteries. The narrowing limits blood flow to the heart muscle. A heart attack happens when blood flow is completely blocked.
Call 911 or other emergency services immediately if you have symptoms of acute coronary syndrome. These may include:
After you call 911, the operator may tell you to chew 1 adult-strength or 2 to 4 low-dose aspirin. Wait for an ambulance. Do not try to drive yourself.
A doctor will give you a physical exam and ask about your symptoms and past health. He or she also will ask about your family's health. You will have several tests to find out what is causing your symptoms.
An electrocardiogram can show whether you have angina or have had a heart attack. This test measures the electrical signals that control your heart's rhythm. Small pads or patches will be taped to your chest and other areas of your body. They connect to a machine that traces the signals onto paper. The doctor will look for certain changes on the graph to see if your heart is not getting enough blood or if you are having a heart attack.
A blood test will look for a rise in cardiac enzymes. The heart releases these substances when it is damaged.
In some cases, you might have a test called a cardiac perfusion scan to see if your heart is getting enough blood. It also can be used to check for areas of damage after a heart attack.
If you call 911, treatment will start in the ambulance with aspirin and other medicines.
In the hospital, the doctor will work right away to return blood flow to your heart. You may get medicines to break up and prevent blood clots. You may get nitroglycerin and other medicines that make your arteries wider. This helps improve blood flow and relieve symptoms, such as chest pain or pressure. You also may get pain medicine and oxygen.
Your test results will help your doctor decide about more treatment. You might have angioplasty or bypass surgery to improve blood flow to your heart.
After you get out of the hospital, you will continue to take medicines that lower your risk of a heart attack. Medicine may include beta-blockers, aspirin or other medicines to prevent blood clots, blood pressure medicine, and cholesterol medicine.
Healthy lifestyle changes also lower your chance of having a heart attack. Quitting smoking, eating heart-healthy foods, getting regular exercise, and staying at a healthy weight are important steps you can take.
If your doctor has not set you up with a cardiac rehab program, talk to him or her about whether that is right for you. In cardiac rehab, you will get education and support that help you make new, healthy habits, such as eating healthy food and getting more exercise.
A heart-healthy lifestyle can help prevent heart disease, which can lead to acute coronary syndrome. If you already have heart disease, a heart-healthy lifestyle along with medicine can help prevent a heart attack.
Other Works Consulted
Amsterdam EA, et al. (2014). 2014 AHA/ACC guideline for the management of patients with non-ST-elevation acute coronary syndromes. Circulation, 130(25): e344–e426. DOI: 10.1161/CIR.0000000000000134. Accessed October 24, 2014.
Jneid H, et al. (2017). 2017 AHA/ACC clinical performance and quality measures for adults with ST-elevation and non-ST-elevation myocardial infarction: A report of the American College of Cardiology/American Heart Association Task Force on Performance Measures. Circulation: Cardiovascular Quality and Outcomes, 10(10): e000032. DOI: 10.1161/HCQ.0000000000000032. Accessed September 25, 2017.
Kim MC, et al. (2011). Definitions of acute coronary syndromes. In V Fuster et al., eds., Hurst's the Heart, 13th ed., vol. 2, pp. 1287–1295. New York: McGraw-Hill.
O'Connor RE, et al. (2010). Acute coronary syndromes: 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care. Circulation, 122(18): S787–S817.
Rosendorff C, et al. (2015). Treatment of hypertension in patients with coronary artery disease: A scientific statement from the American Heart Association, American College of Cardiology, and American Society of Hypertension. Circulation, 131(19): e435–e470. DOI: 10.1161/CIR.0000000000000207. Accessed March 31, 2015.
Thygesen K, et al. (2012). Third universal definition of myocardial infarction. Circulation, 126(16): 2020–2035. Also available online: http://circ.ahajournals.org/content/126/16/2020.
Current as of:
December 16, 2019
Author: Healthwise StaffMedical Review: Rakesh K. Pai MD, FACC - Cardiology, ElectrophysiologyE. Gregory Thompson MD - Internal MedicineMartin J. Gabica MD - Family MedicineAdam Husney MD - Family MedicineKathleen Romito MD - Family MedicineGeorge Philippides MD - Cardiology
Current as of: December 16, 2019
Author: Healthwise Staff
Medical Review:Rakesh K. Pai MD, FACC - Cardiology, Electrophysiology & E. Gregory Thompson MD - Internal Medicine & Martin J. Gabica MD - Family Medicine & Adam Husney MD - Family Medicine & Kathleen Romito MD - Family Medicine & George Philippides MD - Cardiology
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