Coronary Artery Disease
(CAD · Heart Disease)
In this condition factsheet:
The Facts on Coronary Artery Disease
Coronary artery disease (CAD), the most common type of heart disease, refers to the narrowing of arteries that supply blood to the heart due to a build-up of a sticky substance called plaque. The heart muscle does not get enough oxygen when heart arteries are narrowed. If the heart is starved of oxygen, chest pain (angina) occurs. A piece of the plaque may break off and cause the body to form a clot on the damaged artery, cutting off oxygen to the heart and leading to a heart attack. A heart attack is medically referred to as a myocardial infarction (MI) and is one of the leading killers of both men and women.
Many of these deaths can be prevented because some risk factors for CAD are controllable. These controllable risk factors include high blood pressure, high blood cholesterol, and diabetes. There are other controllable risk factors related to lifestyle, such as not smoking, maintaining a healthy weight, eating a healthy diet, reducing alcohol consumption, and being physically active.
Although medical treatments for heart disease have come a long way, controlling risk factors remains the key to preventing illness and death from CAD.
Causes of Coronary Artery Disease
A low supply of oxygen in the heart is most often caused by atherosclerosis, also called "hardening of the arteries." In this condition, fatty deposits called plaques form in the linings of the blood vessels. The plaques make the arteries narrower as they build up, and less blood is able to get through to the heart, depriving it of oxygen.
Atherosclerosis is often the result of too much "bad" cholesterol (low density lipoprotein, or LDL) and triglycerides circulating in the bloodstream.
You are at risk for developing atherosclerosis and CAD if you:
- have high levels of "bad" (LDL) cholesterol
- low levels of "good" (HDL, or high density lipoprotein) cholesterol
- have high blood pressure
- are a smoker
- have diabetes
- have an unhealthy diet
- lead a sedentary lifestyle
- are overweight (particularly if you are obese in the torso or have a large waist circumference)
- have a family history of heart disease
- consume alcohol excessively
Occasionally, a genetic condition can cause atherosclerosis, leading to heart disease.
In Canada, men are twice as likely to develop coronary artery disease than women.
Symptoms and Complications of Coronary Artery Disease
Some people with CAD might have no symptoms until the disease is severe enough to cause chest pains, or angina pectoris (angina comes from the Greek word for "strangling").
Stable angina is often the first sign that a person has CAD. Chest pain or discomfort occurs with activity and is relieved by rest. With unstable angina, symptoms become less predictable and can occur when you are at rest. This indicates rapid progression of CAD and higher risk of a heart attack and requires that you see a doctor immediately.
Some symptoms of angina include:
- tightness or a squeezing sensation across the chest
- burning or pressure beneath the breast bone
- pain or ache radiating to the shoulders, jaw, arms, throat, neck, or upper abdomen
- fatigue
- sweating
- weakness
- shortness of breath
- lightheadedness
If a plaque lining a blood vessel ruptures, it may completely block an area of the heart from receiving the oxygen-rich blood supply it needs. The starved cells in that area will then die, resulting in a heart attack.
The symptoms of a heart attack are similar to those of angina, but much stronger.
Men will often feel:
- constant pain in the middle of the chest that may radiate to the neck, jaw, left shoulder, or arm
- tightness or squeezing in the chest
- a sensation of "heaviness" or heavy indigestion
- sweating, nausea, and vomiting
- shortness of breath
- anxiety, fear, or denial
In women, the main symptoms can be similar to men but may also include:
- shoulder, neck, or back pain
- feeling a sharp pain on breathing in cold air
- unusual fatigue or weakness
It's very important to immediately call 9-1-1, or get medical help as quickly as possible if you feel you have the symptoms of a heart attack.
