What is coronary artery disease?
Coronary artery disease (CAD) is the most common form of heart disease. It occurs when one or more of the coronary arteries becomes narrow or blocked. Normally, blood flows through blood vessels like water through a hose. In coronary artery disease, the coronary arteries become narrowed or blocked, which reduces blood flow to the heart. This is often called hardening of the arteries or atherosclerosis.
CAD can cause:
- Chest pain (angina)
- Heart attack (myocardial infarction)
- Sudden stopping of the heart (cardiac arrest)
Who is at risk?
Risk factors for heart disease are conditions or habits that make it more likely that you will get heart disease. Some risk factors for coronary artery disease can be changed and others cannot.
Risk factors you can change:
- High blood pressure
- High blood cholesterol and triglycerides
- Unhealthy weight
- Unhealthy diet
- Too much alcohol
- Not enough physical activity
- Smoking or chewing tobacco
Risk factors you cannot change:
- Age – the older you are, the higher your risk of heart disease.
- Sex – Your risk of heart disease and stroke increases after menopause.
- Family history – if you have a close relative who has experienced heart disease at an early age, you are at an increased risk. In addition, Women who have had pre-eclampsia during pregnancy have an increased risk.
- Indigenous heritage – First Nations, Metis and Inuit peoples are more likely to have high blood pressure and diabetes. They are at greater risk of heart disease than the general population.
- South Asian and African heritage – people of African or South Asian background also have a higher risk of heart disease. This is because they are more likely to have high blood pressure (hypertension), diabetes or other risk factors for heart disease at a younger age.
- Environmental Factors - Environmental factors such as access to healthy food and safe drinking water, poverty and access to health care are known to influence health.
Over many years, plaque builds up on artery walls. Plaque is a sticky, yellow substance made of fatty substances like cholesterol, as well as calcium and waste products from your cells. It narrows and clogs the arteries, slowing the flow of blood. This condition is called atherosclerosis, which may begin as early as childhood. It can occur anywhere in the body, but it usually affects large and medium-sized arteries.
Sometimes plaque in an artery can rupture. The body's repair system creates a blood clot to heal the wound. But the clot can block the artery, leading to either a heart attack or stroke.
The factors that cause plaque to build up are:
- Damage or injury to the inner layer of the coronary arteries caused by the risk factors listed above.
- Over the years, plaque accumulates at the site of the injury in a process called atherosclerosis or hardening of the arteries.
Early warning signs may include:
They can also include the symptoms associated with angina:
- A squeezing, suffocating or burning feeling in your chest that tends to start in the centre of your chest but may move to your arm, neck, back, throat or jaw.
Women are more likely to experience non-traditional symptoms such as:
- Vague chest discomfort
- Sleep difficulties
If left untreated, CAD can lead to other serious problems such as heart attack, stroke or even death.
Your doctor will start by taking a medical history, doing a physical exam and ordering some chest X-rays. Your doctor may also want to do some of these other tests:
- Electrocardiogram (ECG/EKG)
- Stress test
- Nuclear stress test (also called: thallium scan, cardiolite scan, nuclear perfusion imaging, myocardial perfusion scan or myocardial perfusion imaging [MPI], radionuclide test).
There is no cure for CAD, but there are many treatments, including medications, surgery and lifestyle changes, that can slow down its progress.
Medications used to treat coronary artery disease include:
Surgical and non-surgical procedures
Your doctor may also suggest these procedures:
You can lower your risk of coronary artery disease by knowing and controlling your blood pressure, diabetes and blood cholesterol. It is also important to lead a healthy lifestyle by being smoke-free and physically active, eating a healthy diet that is lower in fat, especially saturated and trans fat, achieving and maintaining a healthy weight, limiting alcohol use and reducing your stress.
To find useful services to help you on your journey with heart disease, see our services and resources listing.