Atherosclerosis

Atherosclerosis is the buildup of fatty deposits, called plaque, over time in the walls of our arteries. Plaque (also called atheroma) is made up of cholesterol, calcium, fat and other substances.

The buildup of plaque causes the wall of the arteries to get harder and thicker.

Our arteries are the blood vessels in our body that carry oxygen-rich blood to our organs and tissues. The main artery in the body is called the aorta, which carries blood away from the heart to the rest of our body.

Atherosclerosis is often referred to as a silent disease. This means that the hardening of the arteries may not cause symptoms in the early stages. However, as the plaque builds up and the artery begins to narrow, there is less room for blood to flow through the vessel and less blood is able to reach your body’s organs and tissues. The force of blood flow in the restricted artery can cause plaque to erode or rupture, leading to the formation of a blood clot.

Where the blood clot has formed, will affect where the symptoms appear. Blood flow can be blocked to certain organs or tissues that the artery normally feeds. If a coronary artery is blocked – the blood vessels that feed the heart with oxygen rich blood – then it can cause a heart attack.

In addition to a heart attack, complications associated with atherosclerosis and a restricted blood flow include:

• Aneurysms
• Carotid artery disease
• Coronary artery disease
• Mesenteric ischemia
• Peripheral artery disease
• Renal artery stenosis
• Stroke
• Transient ischemic attack (TIA)

Atherosclerosis is a common condition, and the complications associated with a buildup of plaque are a leading cause of death globally.

The good news is there are things you can do to lower your risk of atherosclerosis. Making simple lifestyle changes and managing underlying conditions can make a difference. Screening is important as early diagnosis and treatment can help to avoid or delay complications.

Cardiologists recommend having a heart check-up every year to look for the early stages of heart diseases such as atherosclerosis. They can also assess your risk of developing heart disease can what you can do to lower your risk.

Symptoms of atherosclerosis

The symptoms of atherosclerosis often don’t appear until the artery is very blocked or narrow. Sometimes, the first sign is a medical emergency such as a stroke or heart attack.

Common symptoms and complications of atherosclerosis might include:

Coronary artery disease: Symptoms include angina, shortness of breath and sometimes a heart attack.

Heart attack: Symptoms of a heart attack might include chest pain, shortness of breath, feeling dizzy, heart palpitations or pain in the neck, back, arms, shoulders, or belly.

Mesenteric ischemia: Symptoms include pain after eating, diarrhea, bloating and nausea.

Peripheral artery disease: Signs often include leg pain when active, aching in the feet, reddening of the skin, sores on the feet, skin issues on the legs and feet.

Renal artery stenosis: Symptoms may include swelling, high blood pressure, tiredness, headaches, weight loss and nausea.

Stroke or transient ischemic attack (TIA): Symptoms include drooping of one side of the face, headache, dizziness, slurred speech, vision loss in one eye or loss of muscle strength in one side of the body. Recognizing the early signs of a stroke is very important as it requires immediate medical attention. Learn more here.

Carotid artery disease: Often, the first signs are a stroke or TIA.

Causes of atherosclerosis

Atherosclerosis is the buildup of fatty deposits in the arteries, causing them to harden and narrow. It can take many years to develop.

Atherosclerosis begins due to damage to the inner lining of the artery, called the endothelium. This damage may be caused by high cholesterol, or toxins from smoking, and lead to inflammation within the artery.

The next stage of atherosclerosis is the formation of a fatty streak at the site of the endothelial damage. At the site of the damage, ‘foam’ cells form, which are white blood cells, which consume cholesterol and cause the start of the fatty deposit and cause further endothelial damage.

The next stage is the growth of the plaque as other debris and foam cells attach to it. It forms a fibrous cap that stops bits of the plaque from breaking off and entering the bloodstream. As it grows, the artery’s opening, called the lumen, narrows.

Eventually, the plaque can rupture if the fibrous cap breaks open, or erode, if the endothelial cells around it wears away. Both plaque erosion and rupture can cause a blood clot which blocks the flow of blood and cause a stroke or heart attack.

Risk factors for atherosclerosis

There are lots of risk factors for atherosclerosis. Some are called non-modifiable risk factors, which mean you can’t control or change them, and others are modifiable, which you can control.

Non-modifiable atherosclerosis risk factors include:

• Being over 65 years of age
• Having close relatives with cardiovascular disease

Medical conditions that increase the risk of atherosclerosis include:

• Diabetes
• High blood pressure
• High cholesterol

Modifiable risk factors (lifestyle factor) for atherosclerosis include:

• A diet high in saturated and trans fats, salt and sugar
• An inactive lifestyle
• Being overweight
• Smoking/tobacco use.

Diagnosing atherosclerosis

To diagnose atherosclerosis, a cardiologist will first discuss your medical history, family history, lifestyle and perform a physical examination. They will listen to your heart and the blood flow through the arteries.

Blood tests can indicate cholesterol levels and provide information about your heart’s function.

Additional diagnostic tests might include:

• Angiography: An X-ray, using contrast dye, can locate and measure blockages.
• Ankle/brachial index: The blood pressure in your ankle is compared to the pressure in your arm.
• Chest X-ray: Provides images of inside of your chest.
• CT scan: Obtains pictures and can show narrowing of the larger arteries.
• Echocardiogram (ECG): This takes pictures of the heart’s chambers and valves. It can measure how well the heart is pumping.
• Electrocardiogram (EKG): Measures the heart’s rate, electrical activity and rhythm.
• Exercise stress test: Measures the heart’s function when physically active.
• Carotid ultrasound: Takes pictures of the arteries in the neck which feed the brain with blood and can detect narrowing/hardening.
• Abdominal ultrasound: Takes pictures of the abdominal aorta.

Cardiac catheterization is a diagnostic procedure that can give information about the function and structure of the heart. It involves taking X-rays of the arteries of the heart (coronary arteries). It is an invasive diagnostic procedure in which a thin tube (a catheter) is inserted into a blood vessel and passing it to the coronary arteries. A contrast dye is inserted which shows up on X-ray and highlights narrowed or blocked arteries.

Treatment for atherosclerosis

Treatment for atherosclerosis may begin with lifestyle changes or medication to lower cholesterol, lower blood pressure or prevent blood clots.

In more severe cases, there are many interventional, non-surgical procedures that can help people. An interventional procedure opens a narrowed coronary artery to increase blood flow to the heart.

Interventional procedures can be performed during a diagnostic catheterization when a blockage is identified, or after a catheterization has confirmed the presence of coronary artery disease.

Interventional procedures include:

• Balloon angioplasty: A small balloon is inserted via the catheter near the blocked/narrowed coronary artery. The balloon is inflated, and the blockage or fatty plaque is compressed to the walls of the artery. The blood vessel is then widened (dilated) which increases blood flow to the heart.
• Balloon angioplasty with stenting: A balloon catheter inserts a stent into the narrow artery. As the balloon is inflated, the stent is expanded in the artery, and can hold it open. The balloon is removed, but the stent stays permanently.
• Rotablation (Percutaneous Transluminal Rotational Atherectomy or PTRA): A catheter with a diamond-coated tip, is inserted to the narrowed artery. The tip spins and grinds the plaque away. Microscopic particles that are removed are washed away in the bloodstream.
• Cutting balloon: The catheter is inserted with a balloon which has small blades. The blades score the plaque, and the balloon compresses the plaque into the arterial wall.

Preventing atherosclerosis

It may not be possible to prevent atherosclerosis, but the risk of it developing can be reduced, or the effects of the disease lessened, but making some lifestyle changes:

• Attending regular heart screening.
• Exercising for at least 30 minutes a day.
• Maintaining a healthy weight.
• Managing any existing health conditions such as high blood pressure, high cholesterol and diabetes.
• Reducing your intake of saturated fat, cholesterol, trans fat, salt and sugar.
• Quitting smoking.

Atherosclerosis and heart disease are common conditions, but there are things you can do to lower the risk of them developing. Screening is important as early diagnosis and treatment can help to avoid or delay complications.

The team at our Herat, Vascular & Thoracic Institute offer a wide range of heart services, including the latest interventional procedures and treatments. Learn more.