What is atherosclerosis? 

Atherosclerosis is  the most common cause of heart disease. Atherosclerosis is the hardening and narrowing of the arteries in the heart. It is characterised by the build-up of plaque inside the arteries. There are two types of plaques - stable and unstable - which can affect people in different ways.

Stable Plaques

Stable plaques (or lesions) occur when the walls of your coronary arteries, which carry oxygen and nutrients to your heart, become thickened and stiff because of a build-up of fatty deposits. Healthy arteries are elastic and flexible. A person with atherosclerosis will have hardened arteries due to a build-up of fatty substances, particularly cholesterol, which is deposited in the wall of the arteries and may restrict blood flow to the heart. This is more commonly known as clogged arteries.

Atherosclerosis can occur in large or small arteries throughout your entire body and develops over time. It will often have grave consequences that can lead to heart attack and/or stroke if left untreated.

Unstable Plaques

Unstable plaques can rupture and lift off the artery wall, leading to an acute event such as heart attack, stroke or death. Unstable plaques are potentially more dangerous than stable plaques because of their propensity to rupture and cause complete obstruction to blood flow. 

Late complications of Atherosclerosis
Image credit: Npatchett

What are the symptoms of atherosclerosis?

Symptoms of atherosclerosis can develop if an artery supplying blood to the heart becomes so narrowed that blood flow is restricted substantially. If you have mild atherosclerosis, you may not have any symptoms. 

A severe or sudden blockage can cause heart attack or even sudden death. Otherwise, common symptoms of moderate to severe atherosclerosis in coronary arteries include:

  • Chest pain or angina
  • Shortness of breath
  • Fatigue or dizziness

What are the causes of atherosclerosis?

The exact cause of atherosclerosis is unknown. Scientists do know that it is a slow progressive disease that can begin as early as childhood. The following may contribute to the disease:

  • High blood pressure
  • High blood cholesterol
  • Smoking or tobacco
  • Insulin resistance or diabetes
  • Overweight of obesity
  • Lack of regular exercise
  • Depression
  • Stress
  • Inflammation from diseases such as arthritis, lupus or infections

How is atherosclerosis diagnosed?

To diagnose atherosclerosis your doctor will start by conducting a physical exam, to see if they can find narrowed, enlarged or hardened arteries. They may suggest further diagnostic testing such as:

  • Blood tests
  • Doppler ultrasound
  • Ankle-brachial index
  • Electrocardiogram (ECG)
  • Stress test
  • Cardiac catheterization and angiogram
  • CT scan
  • Magnetic Resonance Angiography (MRA)

How is atherosclerosis treated?

The best treatment for atherosclerosis is to lead a healthy lifestyle. However sometimes medication or surgical procedures are necessary. 


Some medicine can slow or reverse the effects of atherosclerosis including:

  • Cholesterol medications
  • Anti-platelet medications
  • Beta blocker medications
  • Angiotensin-converting enzyme (ACE) inhibitors
  • Calcium channel blockers
  • Diuretics
  • Other medications 

Surgical Procedures 

People with more severe forms of atherosclerosis may need to have one of the following procedures:

  • Angioplasty and stent placement
  • Endarterectomy
  • Fibrinolytic therapy
  • Bypass surgery

Can you unclog blocked arteries?

Getting rid of plaque from your arterial walls is very difficult. Exercising, losing weight or eating foods lower in cholesterol, can slow the further development of plaques. But this won’t remove existing plaques. Plaques can be reduced in size with aggressive medical treatment, such as with cholesterol-lowering drugs, which can also convert unstable to stable plaques.

Atherosclerosis Patient Stories

How can atherosclerosis be prevented? 

The best way to prevent atherosclerosis is by leading a healthy lifestyle. This includes:

  • Eating healthily
  • Not smoking
  • Controlling and maintaining a healthy weight
  • Exercising regularly
  • Having regular check-ups
  • Managing unhealthy blood cholesterol
  • Controlling stress

Ask your doctor for a heart health check which looks at the key risk signs. Download our Heart Health Risk Assessment Guide to take with you to your next doctor's appointment.

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