Acute coronary syndrome (ACS) refers to a group of symptoms that affects the heart. If you’re experiencing ACS, it means that the blood supply to your heart is lower than it should be. Heart attack and unstable angina are types of ACS. These conditions are medical emergencies.

If you experience chest pain, tightness, or pressure, it may show a problem with your heart. Heartburn or chest muscle strain can also cause chest pain. But those conditions each have a distinct feeling.

ACS chest pain will feel different than a bout of heartburn, or the soreness you might feel after straining a muscle or tendon.

Other symptoms of ACS can include:

  • shortness of breath
  • feeling dizzy or lightheaded
  • nausea

The pain associated with ACS may also extend from the center of the chest out to one or both sides of your chest. You could also feel pain or discomfort in the following areas:

  • back
  • neck
  • jaw
  • arms

Left arm pain is often considered a heart attack symptom, but you could have pain in your right arm or both arms.

The primary symptom of unstable angina is chest pain. It can come on at any time, unlike stable angina, which produces chest pain when the heart is working harder with exercise. Unstable angina could appear during physical activity or while you’re inactive. Unstable angina is a greater risk for heart attack than stable angina.

Blockage in the arteries that supply blood to the heart muscle causes ACS. Arteries can become blocked or narrowed due to the buildup of plaque along the artery walls.

Plaque contains:

  • LDL, or “bad,” cholesterol
  • other fats
  • white blood cells
  • other substances

Plaque can grow so much that there is little room for blood to flow through the artery. Sometimes the plaque can actually cut off blood flow. Plaque can also rupture, spilling its contents into the artery and forming a blood clot. If the clot is big enough, it can plug up the blood vessel and cause a heart attack.

Coronary arteries are the arteries that supply blood to the heart muscle. They can also become damaged from smoking or diabetes. Being obese and physically inactive can also contribute to ACS.

You’re at a higher risk for ACS if there is a family history of the condition. Elevated LDL cholesterol levels or blood pressure also increase your risk. Smokers are also more likely to develop ACS.

Diabetes also increases your odds of developing cardiovascular problems such as ACS. That’s because elevated levels of blood sugar in your system can injure your blood vessels.

ACS can lead to other complications, especially if it’s not treated. A heart attack can cause significant damage to the heart muscle, weakening it and increasing the risk of developing heart failure. If a heart attack is severe, but isn’t treated quickly, it can be fatal.

Your doctor may use a blood test and an electrocardiogram (EKG) to diagnose ACS. Markers in your blood can reveal that heart cells are dying. An EKG measures the electrical activity in the heart. If the heart muscle is deprived of oxygenated blood, the electrical system that keeps the heart beating regularly can be changed.

Your doctor may also order a coronary angiogram. That is a screening test that reveals blood flow in your heart. During the test your doctor will thread a catheter to your heart to release a type of dye into your bloodstream.

Then, using special X-ray equipment, they will be able to track the movement of your blood through your heart. The dye makes it easier to see how your blood is moving. This can show if blood flow is restricted in one or more coronary arteries.

If you experience ACS, re-starting or improving blood flow to the heart muscle fast is essential. That can be done with a procedure called percutaneous coronary intervention (PCI), or with a type of open-heart surgery called coronary artery bypass grafting (CABG).

In PCI, your doctor threads a catheter through an artery to the heart. At the end of the catheter is a tiny balloon that is inflated to open up the artery. Often a flexible mesh tube called a stent is left in place to help keep the artery open.

During a CABG, a surgeon opens up the chest cavity, takes a vein or artery from another part of the body, and attaches it to the blocked artery above and below the blockage. Blood is rerouted through the attached vein, bypassing the blocked part of the artery.

Receiving a stent or undergoing bypass surgery doesn’t mean your heart health problems are over. If you had plaque buildup in one coronary artery, chances are you may have buildup now or in the future in other blood vessels. This may mean later surgeries, or more stents and medications to try to prevent future ACS.

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Advances in treatments and medication have improved the outlook for ACS. Also, a better understanding of ways to keep hearts healthy means that people who survive heart attacks are living longer and with a greater quality of life.

If you have a history of ACS, you will need to manage your heart health for the rest of your life. That means regular visits to a cardiologist and taking medications to prevent plaque, control your cholesterol, and control your blood pressure.

One of the best decisions you can make as someone with ACS is to take part in cardiac rehabilitation. If you’ve undergone PCI or CABG, chances are your doctor has recommended cardiac rehab. If not, you should inquire about it.

Cardiac rehab is an individualized program of supervised exercise and education about medication adherence, diet, and other heart-healthy behaviors. The length of your cardiac rehab will depend on the severity of your condition.

Other tips include managing your cholesterol, blood pressure, and blood sugar levels with a healthy lifestyle and medications. The American Heart Association recommends 150 minutes of physical activity every week for good heart health. Also, follow a Mediterranean-style diet, which prioritizes:

  • fruits
  • vegetables
  • whole grains
  • nuts
  • legumes
  • fish
  • healthy fats
  • olive oil

You should also quit smoking if you smoke, and maintain a healthy weight. Obesity and smoking both put strain on the heart and your blood vessels. Talk to your doctor about smoking cessation programs and ways to maintain a healthy weight.