Acute coronary syndrome (ACS) refers to three types of coronary artery disease that affect millions of people each year. It's a medical emergency that can cause unstable angina and heart attack due to artery blockage. With prompt attention, treatment can quickly reopen arteries and help restore blood to your heart, so it can work properly.
Acute coronary syndrome (ACS) is a broad term for three types of coronary artery disease that affect millions of people each year. These potentially life-threatening conditions occur when a blockage causes blood flow to your heart to suddenly slow or stop.
Acute coronary syndrome is a medical emergency that requires immediate attention. Prompt treatment is important to ease symptoms and prevent complications. If you think you're having a heart attack, take an aspirin and call 911 immediately.
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Acute coronary syndrome involves three types of coronary artery disease that damage or destroy heart tissue. The specific type depends on:
Types of ACS are:
Acute coronary syndrome can affect anyone. However, certain risk factors raise the likelihood of developing ACS.
Age and lifestyle:
Conditions you have (or had) and family history:
Other conditions can cause non-cardiac chest pain and symptoms resembling acute coronary syndrome. Get prompt medical care so you can get an accurate diagnosis and the right treatment. Conditions similar to ACS include:
Coronary artery disease (CAD) is the most common heart disease in the U.S. and the leading cause of death. Acute coronary syndrome, a type of CAD, causes almost 400,000 deaths every year, most often among people assigned male at birth and those with underlying coronary heart disease.
Your heart is a muscle that needs a constant flow of oxygen-rich blood to work properly. Coronary arteries and their smaller vessels supply this blood.
Sometimes, a gradual buildup of fat and cholesterol (plaque) hardens and narrows your arteries (atherosclerosis). Acute coronary syndrome can occur suddenly when this plaque tears or splits open.
A blood clot forms over the opening, narrowing or blocking blood flow to a part of your heart called the myocardium. The heart can't get enough oxygen. Lack of oxygen (ischemia) damages the heart muscle, leading to unstable angina or heart attack.
Rarely, acute coronary syndrome is caused by:
Symptoms of acute coronary syndrome vary based on the location and severity of the blockage. Your symptoms also depend on your age, sex and other medical conditions, like diabetes.
Signs of ACS typically occur without warning, even while you rest. The syndrome often causes chest pain or discomfort (angina). This can feel like:
The sensation may spread to your left shoulder, arms, neck, back or jaw. However, some people don't have chest symptoms at all.
Other common symptoms include:
People assigned female at birth who have acute coronary syndrome often don’t have chest symptoms. They’re more likely than people assigned male at birth to experience:
Alert your healthcare provider as soon as possible if symptoms persist or get worse. If you think you’re having a heart attack, take an aspirin and call 911 or go immediately to an emergency room.
Healthcare providers diagnose acute coronary syndrome using a physical exam, blood tests and an EKG, which records your heart's electrical activity. The results help your healthcare provider determine if your condition is a heart attack or unstable angina.
Additional exams can help rule out other conditions and guide treatment. Some tests, such as an exercise stress test or medication stress test, increase your heart rate to show how well your heart is working at its hardest.
Acute coronary syndrome is a medical emergency. If results show that blood flow to your heart is blocked, you receive immediate treatment. If you have severe symptoms, like loss of consciousness, you may receive treatment before providers confirm a diagnosis.
There's no cure for acute coronary syndrome, but early diagnosis and prompt treatment can protect your heart from further damage and help it work as well as possible. Your healthcare provider can discuss ways to reduce risks and avoid complications.
Acute coronary syndrome treatment focuses on relieving pain and improving blood flow so your heart can work as well as possible, as quickly as possible. Your healthcare provider recommends treatment based on the specific condition you have. Treatment typically involves a combination of medication and procedures to open your arteries and restore heart function.
The medications you receive depend on your specific condition. In some cases, your provider may give you medication before confirming a diagnosis. Medications may include:
Your healthcare provider may also recommend medicine for related heart issues like:
Surgical treatments for acute coronary syndrome involve reopening your artery to restore regular blood flow. Your healthcare provider may recommend:
Heart-healthy lifestyle changes can help reduce risk factors for acute coronary syndrome and other cardiovascular conditions. Recommendations include:
The outlook for acute coronary syndrome depends on the specific condition and its severity, including the extent of heart muscle damage. Timely diagnosis and treatment, along with lifestyle changes, can help give you the best chance for a healthy life.
Follow your healthcare provider's instructions and maintain heart-healthy habits. Keep all appointments and complete tests that your provider orders. Discuss your ongoing care, so you understand what you can do to reduce risks and avoid complications.
If you've had a heart attack, your provider can recommend a cardiac rehabilitation program to regain strength, reduce health risks and improve your quality of life.
Seek immediate emergency care for symptoms of acute coronary syndrome. Go to the nearest emergency room or call 911 if you have sudden symptoms of ACS or think you’re having a heart attack.
Your medical team will ask you to describe your symptoms, including when they occurred and how severe they are.
The more details you can provide, the better. Consider:
A note from Cleveland Clinic
Acute coronary syndrome is a common heart condition that requires immediate care. You may feel like you are having a heart attack. Don't hesitate to call 911 or go to the nearest emergency room right away. Prompt diagnosis and treatment can put your heart back to work, so you can feel better.
Last reviewed by a Cleveland Clinic medical professional on 05/02/2022.
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