Atherosclerosis (pronounced a·thr·ow·sklr·ow·suhs) is a thickening or hardening of the arteries that carry oxygen-rich blood to different parts of the body. It happens when fat, cholesterol, calcium and other substances build up along the inside of the artery walls.

Over time, atherosclerosis can block or disrupt blood flow through the affected arteries. This can lead to serious problems, including heart attack and stroke.

Why Does It Happen?

While we don’t have all the answers, when the inner lining of the blood vessels are injured, swelling (inflammation) can occur. Usually a thin layer of cells coat the inside of the arteries to keep the lining smooth (endothelium) so that blood can flow easily throughout the body.

But researchers believe that repeated damage to the lining of the blood vessels over time can cause narrowing of the walls of the blood vessels. This may eventually clog arteries.

Damage the lining of blood vessels may happen from:

• Smoking
• High blood pressure
• High levels of fats and cholesterol in the blood
• Diabetes

The exact cause of atherosclerosis isn’t known. But certain traits, habits or conditions (called risk factors) have been linked to a narrowing or hardening of the arteries. These may include:

High cholesterol or high triglycerides (a type of fat in the blood) High blood pressure Smoking Lack of exercise Diabetes Being overweight or obese Chronic kidney disease Eating foods high in sodium, sugar, saturated or trans fats

Older age Family history: If you have a parent or a sibling with early onset of heart disease (before 55 years old for male relatives and before 65 years old for female relatives) History of early menopause (before age 40) Inflammatory diseases Sleep apnea

People don’t usually feel atherosclerosis early on. That’s because it takes time for the arteries to become narrowed enough to cause poor or disrupted blood flow. As plaque builds up in the arteries, symptoms may develop gradually.

If an artery – especially a major artery – becomes narrowed or blocked suddenly, you may have symptoms such as chest pain or a heart attack or stroke.

Symptoms Vary

The symptoms you experience will depend on which arteries are affected.

If there is narrowing in the arteries supplying blood to your…	You might have:
Heart (coronary arteries)	·         Chest or arm pain, pressure or tightness (angina) ·         Shortness of breath ·         Abnormal heartbeat (arrhythmias) ·         Feeling that you might faint ·         Stomach upset or vomitingThis is also called atherosclerotic coronary artery disease. Without treatment, it might lead to a heart attack.
Brain (carotid arteries in your neck)	·         Weakness or fainting ·         Numbness in the face, arms or legs ·         Confusion ·         Dizziness ·         Sudden and severe headache ·         Trouble speakingWithout treatment, this might lead to a stroke or mini stroke (transient ischemic attack)
Legs, arms or pelvis (peripheral)	·         Pain in the calves or buttock after walking ·         Numbness in the feet or toesThis is also called peripheral artery disease. Without treatment, it might lead to poor circulation, slow healing of wounds or skin injuries and internal bleeding (abdominal aneurysm).
Kidneys	·         Loss of appetite ·         Swelling (edema) in your hands or feet ·         Nausea ·         FatigueWithout treatment, this might lead to kidney disease or kidney failure.

In addition to your medical history and a complete physical exam, your health care team may perform other tests, order blood work or imaging tests or recommend procedures to look for any narrowing or blockages in your arteries. For example:

• Electrocardiogram – records the electrical activity of the heart. When hearts are having issues, the electrical signals may get changed or altered which may be an early warning sign.
• Ultrasound – a type of imaging test that uses sound waves to show how the heart is squeezing and how well the different heart valves are working.
• Computed tomography (CT) scan – can look for calcium and other deposits in the blood vessels (also called coronary artery calcium scoring or a coronary calcium scan) that can be an early sign of disease in the arteries.
• Stress test, also called an exercise stress test – shows how your heart works during physical activity
• Coronary angiogram or Heart Cath – A procedure where a doctor places a catheter (thin flexible tube) in the artery of your wrist or groin and uses X-ray to look at your heart’s arteries to see if they are blocked or narrowed, where and by how much. This test uses a special dye, called contrast. It can help your care team determine if you might need treatment to open an artery.
• Ankle brachial index (ABI test) – a test to check the circulation or blood flow in your legs (this is to see if you may have a blockage in the blood vessels in your legs that might point to PAD); it involves taking blood pressure in your ankle and arms and comparing them

Your clinician will help you decide on the right treatment for you. Treatments will depend on:

• Your age
• Your overall health and other health conditions
• Which artery (or arteries) are affected, where in the body, and the extent of disease or how much of the artery is blocked (this is often reported as a percentage – for example, 50% or 90% blocked)
• Your signs and symptoms – how it’s affecting your quality of life
• Your preferences

Making healthy choices every day is the best way to prevent atherosclerosis or slow it down if you already have some narrowing in your arteries. For example:

• Being more active or getting regular exercise, which can help you feel more fit and control blood sugar, cholesterol and blood pressure levels
• Eating heart-healthy foods that are low in saturated fats and high in fiber, including fresh fruits and vegetables, whole grains, nuts and seeds
• Getting to and maintaining a healthy weight
• Avoiding tobacco 
• Checking and maintaining a healthy blood pressure and cholesterol levels

Focus on one change at a time so you don’t feel overwhelmed. Set small goals that are realistic so that you can celebrate successes. For example, if you don’t exercise, challenge yourself to walk for 10 minutes most days; then increase that to 15-minute walks the next week.

Treatment may also include:

• Medications – for example, to lower cholesterol, blood sugar or blood pressure levels; prevent blood clots from forming
• Procedures or surgery to help improve or restore blood flow to the heart. For example:
  • Percutaneous coronary intervention (PCI) or “stents”, a non-surgical procedure that uses a catheter (a thin flexible tube) to thread and place a small structure called a stent to prop open the affected blood vessel(s) in the heart
  • Coronary artery bypass surgery, also called CABG, is open heart surgery to redirect blood to flow around a section of the narrowed or blocked artery to the heart

You care team knows what’s best to help support your heart health. Be sure to ask questions about how to prevent or lessen the chance that you will develop a narrowing or hardening of your arteries.

Consider asking:

• What blood vessels can be affected by atherosclerosis?
• How does it lead to heart attack or stroke?
• What are the early signs of narrowed or hardened arteries?
• How can we tell if my arteries are narrowed?
• Are there changes I can make to live healthier and protect my heart health or slow atherosclerosis?
• How much do high cholesterol or high blood pressure play a role?
• Are there medications that can help limit more damage to my arteries?
• Will I need a procedure to open blocked arteries?
• Can stress or lack of sleep play a role in the health of my arteries?