Acute Coronary Syndrome

Acute coronary syndrome (ACS) is an umbrella term that includes unstable angina, STEMI heart attacks and NSTEMI heart attacks. With all these conditions, a blockage in a coronary artery reduces blood flow to your heart muscle. This means your heart isn’t receiving the blood it needs to work as it should, which could result in irreversible damage to your heart or even sudden cardiac death. You need treatment right away to open the artery and prevent or limit heart damage.

Acute coronary syndromes are life-threatening. Call 911 or your local emergency number right away if you have heart attack symptoms or your angina suddenly feels different than usual. Tell the operator what you’re feeling. Ask if you should take an aspirin.

Types of ACS

There are three acute coronary syndromes:

• Unstable angina: This is chest discomfort that’s different, more severe or happens more often than usual. Unlike stable angina, it occurs at times you wouldn’t expect. It means there’s reduced blood flow in a coronary artery, but no heart damage yet.
• Non-ST-segment elevation myocardial infarction (NSTEMI): This is a heart attack that results from a partial blockage in a coronary artery. It can lead to heart damage.
• ST-segment elevation myocardial infarction (STEMI): This is a heart attack due to a complete blockage in a coronary artery. It’s the most severe ACS. Your heart could be severely damaged (the muscle starts to die), or you could die without quick treatment.

It’s possible for unstable angina to quickly turn into a heart attack. And for an NSTEMI to turn into a STEMI.

Symptoms of acute coronary syndromes

ACS symptoms typically occur without warning, even while you rest. You might have:

• Chest discomfort, which can feel like pain, aching, burning, pressure or tightness
• Pain that spreads to your shoulder, arm, neck, back or jaw
• Shortness of breath
• Dizziness or fainting
• Sudden, excessive sweating
• Fatigue
• Racing or pounding heart
• Upset stomach that may feel like indigestion or heartburn

It’s not always easy to tell if chest pain comes from your heart or something else, like acid reflux. That’s why you should always seek medical care for sudden chest pain. Don’t try to guess the cause or wait it out. If it’s an acute coronary syndrome, every minute can make the difference between surviving and not.

What causes acute coronary syndromes?

A blood clot in your coronary artery causes ACS. This is generally due to cholesterol plaque rupturing inside your artery, but it can happen due to blood clots coming from other sources. The clot partly or completely blocks the space where blood can flow. This means your heart can’t get enough blood. Severe blockages can damage your heart muscle or even be fatal.

You may develop an acute coronary syndrome if you’re living with coronary artery disease. This means you have cholesterol plaque buildup in your arteries. The plaque gradually narrows your arteries over many years. This may cause stable angina, or chest discomfort that comes and goes in predictable patterns, usually when you exercise or are physically active. Your provider may give you medicine to treat these episodes.

But things can quickly change if the surface of that plaque wears away (plaque erosion) or breaks open (plaque rupture). When the plaque ruptures or erodes, blood clots form at the spot and reduce blood flow, leading to unstable angina or a heart attack.

Risk factors

You’re more likely to develop ACS if you:

• Are over age 45 (if you’re male)
• Are over age 50 or past menopause, whichever comes first (if you’re female)
• Have a history of heart disease in your biological family
• Have high blood pressure, high cholesterol or diabetes
• Had preeclampsia, high blood pressure or gestational diabetes during pregnancy
• Have overweight or obesity
• Use cocaine
• Drink too much alcohol
• Don’t get enough physical activity
• Smoke or use tobacco products
• Often eat foods high in sodium, sugar or saturated fat
• Have HIV or AIDS
• Have other autoimmune or inflammatory conditions

How doctors diagnose this condition

Healthcare providers diagnose acute coronary syndromes using a physical exam, blood tests and an EKG, which records your heart’s electrical activity. The results show whether your condition is a heart attack or unstable angina. Providers also review your medical history, including any medications you’re taking.

Further tests can help rule out other conditions and guide treatment. Possible tests you may need include:

• Echocardiogram (echo) to check your heart structure and function
• Heart CT scan or MRI to see detailed pictures of your heart
• Coronary angiogram or CT angiogram to see blood flow and find blockages
• Stress test to learn how your heart responds when it’s working very hard

If results show that blood flow to your heart is blocked, you’ll receive immediate treatment.

Providers may ask you questions if you’re able to speak. They’ll want to know about your symptoms. The more details you can provide, the better. Consider:

• What symptoms do I feel?
• When did they start?
• What was I doing at the time?
• How long did they last?
• What made them go away?

How are acute coronary syndromes treated?

ACS treatment needs to happen fast. The longer a blockage lasts, the greater your risk of heart damage or death. Treatments involve medicines and procedures that open your coronary arteries to improve blood flow to your heart. You may also need medicines to help your heart work better, manage symptoms and lower your risk of complications.

Treatments that open up blocked arteries include:

• Percutaneous coronary intervention (PCI): This procedure is minimally invasive and quickly opens your blocked artery to let blood reach your heart. It’s a common and very effective treatment for acute coronary syndromes. Providers use catheters to reach your heart through blood vessels in your wrist and/or groin.
• Coronary artery bypass grafting (CABG): This open-heart surgery makes a new path for blood to flow around a blockage. It’s sometimes used in emergency situations when PCI isn’t possible or doesn’t work.
• Fibrinolytic therapy: This means you receive medicines through an IV or catheter to break up blood clots. Providers use this instead of PCI in some situations.

Medicines you may need include:

• Antiplatelet drugs and/or anticoagulants: These lower your risk of blood clots.
• Nitroglycerin: This relieves chest pain.
• Statins: These medicines lower blood cholesterol levels. 
• Beta-blockers: These slow your heart rate, help your heart pump better, prevent irregular rhythms and lessen damage to your heart.
• ACE inhibitors or ARBs: These manage risk factors for heart attacks and strokes, improving your chances of survival.

Recovery time

How long it takes to recover from an acute coronary syndrome depends on the specific condition you have. In general, you may need several weeks or months to feel better.

Follow your healthcare provider’s advice as you recover. Don’t push yourself to get “back to normal” too fast. Your provider will tell you when it’s safe to return to usual tasks, like driving, working or lifting heavy objects. They might also recommend that you engage in a cardiac rehabilitation program for monitored exercise after you’ve had an ACS.

When should I see my healthcare provider?

You’ll need to see your provider for regular follow-up appointments and testing. They’ll give you a schedule of when to come in. These visits are crucial as you recover. Your provider will:

• Check your heart function
• See how well treatments are working
• Adjust your medicines or doses as needed
• Advise you on things like heart-healthy eating and physical activity

Be sure to tell your provider if:

• You have new or changing symptoms
• You have side effects from your medicines
• You’re finding it hard to manage worries or anxiety about your heart

It’s common to feel depressed or anxious after having a heart attack or coming close to one. Your provider may recommend counseling or support groups. These can help you learn practical tips for managing any emotions you’re feeling.

Call 911 or your local emergency services number if you think you’re having unstable angina or a heart attack. Don’t drive yourself to the hospital or let anyone else drive you. First responders are prepared to start treating you as soon as they arrive and while you’re in the ambulance. This saves valuable time and can even be lifesaving.

What can I expect if I have an acute coronary syndrome?

Your outlook depends on whether you have unstable angina or a heart attack — and if it’s a heart attack, how severe it is. Unstable angina usually doesn’t damage your heart muscle. But a heart attack can. A STEMI typically causes more damage than an NSTEMI.

Your healthcare provider is the best person to tell you what you can expect. In general, treatments have come a long way over the years. Many people live just as long as others their age who don’t have an acute coronary syndrome. You can improve your chances of survival by going to your follow-up visits and sticking to your treatment plan. 

How can I prevent acute coronary syndromes?

It’s not always possible to prevent ACS. You can’t change many things, like age or family history. But there are some steps you can take to lower your risk:

• Don’t smoke or use tobacco products: If you do, ask your healthcare provider about ways to quit, like programs and medicines.
• Eat heart-healthy foods: Talk to your provider or a registered dietitian about foods to eat or avoid. Small changes add up over time. Providers often recommend the Mediterranean diet and DASH diet.
• Limit alcohol use: Alcohol can raise your blood pressure and cause other heart issues. Talk to your provider about ways to limit or avoid alcohol and how this can help you. 
• Take your medicines: If your provider prescribes you medicine for high blood pressure, high cholesterol or diabetes, take them exactly as prescribed. Managing these risk factors for heart disease can lower your risk of ACS and other serious issues down the road.
• Stay active: Physical activity helps you manage your weight, strengthen your heart and relieve stress. Talk to your healthcare provider before you start any exercise program.