Understanding Acute Coronary Syndrome (ACS): What Patients Need to Know

Acute coronary syndrome (ACS) is a term doctors use for conditions where the heart suddenly doesn’t get enough blood and oxygen. This is a medical emergency and needs urgent treatment. In Australia, more than 57,000 people experience an ACS event every year—about one every nine minutes.

This blog explains what ACS is, what the symptoms look like, how it’s treated, and what you can do to stay healthy afterward.

What is Acute Coronary Syndrome (ACS)?

ACS includes three related heart conditions:

1. ST-Elevation Heart Attack (STEMI)

A major heart attack caused by a complete blockage of a heart artery.

2. Non–ST Elevation Heart Attack (NSTEMI)

A heart attack where the artery is partially blocked, causing heart muscle damage.

3. Unstable Angina

Chest pain caused by reduced blood flow, but without permanent heart damage. This condition can progress into a heart attack if not treated.

In all three conditions, the underlying problem is similar: fatty plaques inside heart arteries become unstable and trigger a blood clot, reducing or stopping blood flow to the heart.

Why Does ACS Happen?

Most ACS events start with an unstable cholesterol plaque inside a coronary artery. This plaque can crack, rupture, or become inflamed, leading to the formation of a blood clot. If the clot blocks the artery:

• Blood can’t reach the heart muscle

• The muscle becomes starved of oxygen

• Damage—and sometimes permanent scarring—occurs

This is why fast treatment saves heart muscle and saves lives.

Common Symptoms of ACS

Not everyone experiences symptoms the same way, but the following signs should never be ignored:

• Chest pain or discomfort (pressure, squeezing, heaviness)

• Shortness of breath

• Pain in the left arm

• Pain in the jaw, back, or stomach

• Nausea or epigastric (upper stomach) pain

• Sweating or feeling faint

If you experience any of these symptoms—especially if they’re new, severe, or getting worse—call emergency services immediately (000).

How Doctors Diagnose ACS

When you arrive at the hospital, you may receive:

• An ECG (a heart tracing)

• A blood test for troponin, a marker of heart muscle damage

• A physical exam and questions about your symptoms

These tests help determine whether you’re having a heart attack, unstable angina, or another condition.

How ACS is Treated

Treatment depends on the type of ACS, but the goals are the same:

• Restore blood flow

• Prevent the clot from getting bigger

• Protect the heart muscle

• Reduce the risk of future events

  
  

1. Treating STEMI (Major Heart Attack)

Immediate treatment is critical. Options include:

• Emergency angioplasty (PCI): a stent is placed to open the blocked artery.

• Clot-busting medication if PCI isn’t available quickly.

  
  

2. Treating NSTEMI

Treatment focuses on:

• Medications to stabilize the heart and prevent the clot from growing.

• Angiography and possible stent placement.

  
  

3. Treating Unstable Angina

Even though there’s no heart muscle damage yet, it’s still an emergency. Close monitoring and medications help prevent a heart attack.

Common Medications Used in ACS

Aspirin

Given immediately to help prevent further clotting.

P2Y12 inhibitors (e.g., clopidogrel, ticagrelor, prasugrel)

Work with aspirin to reduce the risk of a new clot forming.

Statins

Lower cholesterol and stabilize plaques.

Beta blockers

Slow the heart and reduce its workload.

ACE inhibitors or ARBs

Protect the heart and kidneys and support long-term recovery.

Colchicine

A low-dose anti-inflammatory used long-term to reduce inflammation in the heart arteries.

Your exact treatment will depend on your heart function, other medical conditions, and your bleeding risk.

Life After an ACS Event

Even after leaving the hospital, it’s normal to feel worried. But with the right steps, recovery can be smooth and your future risk can be reduced dramatically.

1. Cardiac Rehabilitation

A supervised program that includes:

• Safe exercise

• Education

• Emotional support

• Help with medication management

People who attend cardiac rehab have better outcomes and fewer future heart problems.

2. Healthy Lifestyle Changes

Your healthcare team may recommend:

• A heart-healthy diet (low in saturated fat and salt)

• Regular physical activity

• Stopping smoking or vaping

• Limiting alcohol

• Managing stress, anxiety, and depression

• Maintaining a healthy weight

  
  

3. Staying Up-to-Date with Vaccinations

Influenza and other respiratory infections can worsen heart conditions, so staying vaccinated is important.

4. Taking Your Medicines Long-Term

Many heart medications are prescribed for months to years, not just during the hospital stay. These medicines:

• Reduce inflammation

• Lower cholesterol

• Prevent new clots

• Protect the heart muscle

Stopping them early can significantly increase future risk, so always speak to your doctor first.

Acute coronary syndrome is serious, but early treatment and long-term prevention make a huge difference. Knowing the warning signs, understanding your medications, and staying engaged in your recovery all help protect your heart for years to come.

If you have questions about your medications or recovery plan, a Home Medication Review (HMR) can help you understand each step.