Acute Coronary Syndrome

An acute coronary syndrome happens when blood flow to the heart muscle is suddenly blocked. Heart attack and unstable angina are two examples of ACS.

If a blood clot forms due to a plaque rupture, a part of the clot may break away and block one of the coronary arteries causing ACS. Though less common, spasms in the coronary artery may also limit blood flow. Regardless of the cause of the blockage, it’s damaging to the heart and a medical emergency.   

What are the symptoms?

Chest pain or discomfort may immediately signal something’s wrong with your heart. But other symptoms may leave you unsure of what’s wrong. Take note of these common symptoms of ACS:

• Chest pain or discomfort, which feels like pressure around the chest, tightness, burning or aching
• Pain or discomfort that spreads to neck, jaw, shoulders, arms, stomach or back
• Shortness of breath
• Feeling dizzy or lightheaded
• Nausea
• Sweating

Take these symptoms seriously. If you have chest pain or other symptoms, call 911 right away.

Chest pain caused by acute coronary syndromes  can come on suddenly. Other times, the pain can be unpredictable or get worse even with rest. Both are typical symptoms of unstable angina. People with chronic chest pain due to cholesterol buildup in their arteries can develop an ACS if a blood clot forms on top of the plaque.

How is it diagnosed and treated?

To find out what’s causing your symptoms, a health care professional will take your medical history and examine you. If ACS is suspected, these tests may be performed: 

• A blood test can show evidence that heart cells are dying.
• An electrocardiogram (ECG or EKG) can diagnose an ACS by measuring the heart’s electrical activity.

If tests show that blood flow to the heart has been blocked, your health care team will work quickly to restore it. Every second counts to stop further damage to the heart muscle.

Treatment for ACS includes medicines and a procedure known as angioplasty, During angioplasty, doctors inflate a small balloon inside the artery to open it up. A wire mesh tube called a stent may then be  placed in the artery to keep it open. If angioplasty can’t happen right away, you may receive medications to dissolve blood clots. 

View an illustration of coronary arteries(link opens in new window). 

Am I at risk?

Acute coronary syndromes are more likely in people who have certain risk factors. These include:

• Smoking
• High blood pressure
• High blood cholesterol
• Diabetes
• Physical inactivity
• Being overweight or obese
• A family history of chest pain, heart disease or stroke

Your health care professional can help you understand your risk and what you can do about it.