Acute Coronary Syndrome

(ACS; Unstable Angina)


Acute coronary syndrome (ACS) is a set of features related to poor blood flow to the heart muscle that leads to a heart attack. This results in chest pain or angina pectoris. ACS is a serious, life-threatening condition. If you think you have ACS, seek emergency medical treatment.


ACS is caused by a sudden blockage of the coronary arteries. These blood vessels carry blood to the heart muscle. The blood flow to the heart muscle is either greatly reduced or completely blocked. This leads to heart muscle damage or death from a heart attack.
The narrowing most often happens from years of plaque buildup in an artery. This is called atherosclerosis. Blood clots may often cause the narrowing arteries.
Coronary Artery
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Risk Factors

ACS is more common in men over 45 years old and women over 55 years old.
Factors that increase your risk of developing ACS include:


ACS is serious. It requires emergency medical treatment. Contact your doctor if you have any of these symptoms:


You will be asked about your symptoms and medical history. A physical exam will be done. If you suspect ACS, call for emergency medical services.
Your bodily fluids may need to be tested. This can be done with blood tests.
Your heart function may need to be tested. This can be done with:
Detailed images of your heart may need to be taken. These can be done with:


If you are having a heart attack, doctors will:
To restore blood flow, the main treatments are:


To help reduce your chances of getting ACS:


American College of Cardiology

American Heart Association


Canadian Cardiovascular Society

Heart and Stroke Foundation of Canada


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