Understanding heart disease

Understanding heart disease is an important step to taking action to help reduce your risk of developing cardiovascular problems. The heart pumps blood throughout the body, carrying oxygen to the heart and the rest of the body through blood vessels called arteries.

Sometimes a fatty material called plaque builds up in the arteries. Plaque can narrow the arteries and inhibit the flow of blood and oxygen. Plaque buildup in the coronary arteries can lead to a heart attack (medically known as a myocardial infarction).

Some risk factors for heart disease can't be controlled: age, gender or family history.

Other heart disease risk factors can be controlled, such as high blood cholesterol, high blood pressure, diabetes, smoking, physical activity or being overweight.

How heart disease develops

Heart disease develops when plaque clogs or blocks one or more coronary arteries (atherosclerosis).

Atherosclerosis develops in stages. First, medical conditions, poor lifestyle habits or other factors damage the walls of the coronary arteries. Cholesterol and other fatty substances in the blood collect on the damaged artery walls.

The fatty substances build up, layer upon layer, and form a hard substance called plaque. The plaque buildup narrows the artery, decreasing or blocking the flow of blood.

Healthy vs. unhealthy arteries

Healthy arteries have flexible walls and smooth inner linings. Blood flows freely through them to deliver oxygen all over the body. Coronary arteries, which lie on the outside surface of the heart, deliver oxygen-rich blood to the heart muscle.

If an artery's inner lining is damaged, cholesterol and other harmful fats in the blood can collect in the artery wall. This buildup forms plaque, which narrows the channel where blood flows. As a result, less blood can flow through. If plaque breaks open or a blood clot forms, the artery may be blocked entirely. With heart disease, these problems occur in the coronary arteries. Heart disease is also called coronary artery disease or CAD.

What's at risk

Damage to a coronary artery causes less blood to flow to the heart muscle. The decreased blood flow may lead to chest pain, a common symptom of angina. When a coronary is blocked, oxygen-rich blood can't reach the heart muscle artery beyond the block, and a heart attack occurs. If the muscle goes without oxygen for too long, that part of the heart muscle dies.

If an artery that carries blood to the kidneys is blocked, the kidneys may be damaged.

Aortic aneurysm

The aorta is the body's main artery. If this artery is damaged, the affected section can weaken and balloon out, which is called an aortic aneurysm.


Arteries to the brain can become blocked. When this happens, part of the brain can't get oxygen and is damaged, causing a stroke. Stroke can result in speech and memory problems, paralysis and even death.

Peripheral artery disease (PAD)

If the arteries in the leg are clogged with plaque, you may have cramping or aching in your thighs, calves or buttocks when you walk. This is known as peripheral artery disease or PAD.

Is it angina or a heart attack?

Angina does not cause permanent damage to the heart muscle; a heart attack causes permanent damage and can be fatal

Angina symptoms

  • Go away with rest
  • Do not last more than 20 minutes
  • Occur with exertion or excitement

Angina occurs when your coronary arteries are severely blocked. Although scary, angina does not cause permanent damage.

A heart attack occurs when one or more coronary arteries are completely blocked. A heart attack causes permanent damage to the heart muscle and can be fatal.

Heart attack symptoms

  • Do not go away with rest
  • Last more than 20 minutes
  • May occur without activity or excitement

Heart attack warning signs

  • Chest discomfort
  • Discomfort in one or both arms
  • Shortness of breath

  • Back, neck, jaw or stomach discomfort
  • Breaking out in a cold sweat, nausea or lightheadedness

If a heart attack has occurred

  • An electrocardiogram (ECG), a medical device that graphically depicts the heart's electrical activity history, will reveal abnormalities caused by damage to the heart
  • A blood test will show abnormal levels of certain enzymes in the bloodstream
  • A person with diabetes typically does not have the same chest pain symptoms as a non-diabetic

Heart attack symptoms can differ between women and men 

​​​​​​​​​​​​​Heart disease can develop for years without symptoms, and when women have heart attacks, they may experience symptoms besides chest pain. These lists highlight the differences.

Heart attack symptoms in men

  • Chest pain—Discomfort in the center of the chest, often described as crushing.
  • Shortness of breath—May occur simultaneously or before chest pain.
  • Sweating—May break into a sweat with cold, clammy skin. More common in men.
  • Throat, neck, back or jaw pain—Discomfort may be felt in other areas of the upper body.
  • Nausea, vomiting or indigestion—May feel nauseated and vomit.
  • Anxiety—May feel a sense of doom.
  • Fatigue—Fatigue is less common in men.

Heart attack symptoms in women

  • Chest pain—Pain may be mild or absent, often described as pressure, dullness or ache.
  • Shortness of breath—May occur simultaneously or before chest pain. More common in women.
  • Sweating—May break into a sweat with cold, clammy skin.
  • Throat, neck, back or jaw pain—Discomfort may be felt in other areas of the upper body. More common in women.
  • Nausea, vomiting or indigestion—Feel nauseated and vomit. More common in women.
  • Anxiety—Heart attacks in women may be mistaken for panic attacks with shortness of breath, anxiety and indigestion.
  • Fatigue—Many report a sudden onset of unusual fatigue as their only warning sign of a heart attack.

Silent ischemia

Not all heart attacks have obvious symptoms, such as chest pain and shortness of breath. A heart attack can occur without the person knowing due to there being minimum or no symptoms. Silent ischemia occurs when there is a lack of oxygen to the heart muscle due to temporarily blocked blood flow, and it is often referred to as a silent heart attack.

If you believe you are having a heart attack, call 9-1-1 immediately.

What is a stroke?

A stroke occurs when a blood vessel carrying oxygen and nutrients to the brain becomes blocked or bursts.

Stroke warning signs:

  • Numbness of the face, arm or leg, especially on one side of the body
  • Difficulty seeing in one or both eyes
  • Sudden confusion, trouble speaking or understanding
  • Trouble walking, dizziness or loss of balance or coordination
  • Severe headache with no known cause

Behavioral effects of stroke:

  • Depression
  • Difficulty in problem-solving
  • Personality changes

Call 911 immediately if you have symptoms of a heart attack or stroke.