Atherosclerosis is a condition that affects the arteries, the blood vessels that carry oxygen-rich blood to the heart and other organs. It occurs when plaque, a sticky substance made of fat, cholesterol, calcium and other substances, builds up inside the artery walls and narrows them. This reduces the blood flow and oxygen supply to the organs and tissues, and increases the risk of blood clots that can block the arteries completely.
Atherosclerosis can affect any artery in the body, but it is especially dangerous when it affects the coronary arteries (the ones that supply blood to the heart), the carotid arteries (the ones that supply blood to the brain), or the peripheral arteries (the ones that supply blood to the arms, legs and pelvis). Depending on which arteries are affected, atherosclerosis can cause:
- Coronary heart disease: This is the most common form of heart disease and the leading cause of death in the United States. It occurs when plaque builds up in the coronary arteries and reduces blood flow to the heart muscle. This can cause chest pain (angina), shortness of breath, fatigue and irregular heartbeat. If a blood clot forms and blocks a coronary artery, it can cause a heart attack, which can damage or destroy part of the heart muscle.
- Carotid artery disease: This occurs when plaque builds up in the carotid arteries and reduces blood flow to the brain. This can cause transient ischemic attacks (TIAs), which are temporary episodes of numbness, weakness, slurred speech, vision loss or drooping face. These are warning signs of a stroke, which can occur if a blood clot forms and blocks a carotid artery. A stroke can cause permanent brain damage or death.
- Peripheral artery disease (PAD): This occurs when plaque builds up in the peripheral arteries and reduces blood flow to the arms, legs and pelvis. This can cause pain, cramping, numbness or tingling in the affected limbs, especially when walking or exercising. PAD can also increase the risk of infection, ulcers and gangrene in the legs and feet. If severe, PAD may require amputation of a limb.
- Chronic kidney disease: This occurs when plaque builds up in the renal arteries and reduces blood flow to the kidneys. This can impair the kidneys' ability to filter waste and fluids from the blood, leading to high blood pressure, swelling, fatigue and nausea. If untreated, chronic kidney disease can progress to kidney failure, which requires dialysis or a kidney transplant.
Causes of Atherosclerosis
The causes of atherosclerosis are not fully understood, but several factors may contribute to its development and progression. These include:
- High levels of cholesterol and triglycerides in the blood: These are types of fat that circulate in the blood and can accumulate in the artery walls. Low-density lipoprotein (LDL) cholesterol is often called "bad" cholesterol because it contributes to plaque formation. High-density lipoprotein (HDL) cholesterol is often called "good" cholesterol because it helps remove excess cholesterol from the arteries.
- High blood pressure: This is the force of blood pushing against the artery walls. High blood pressure can damage the inner lining of the arteries and make them more prone to plaque buildup.
- Smoking: This damages the inner lining of the arteries and increases the levels of LDL cholesterol and triglycerides in the blood. Smoking also reduces the levels of HDL cholesterol and makes blood more likely to clot.
- Diabetes: This is a condition that causes high levels of glucose (sugar) in the blood. High blood glucose can damage the inner lining of the arteries and increase inflammation. Diabetes also increases the levels of LDL cholesterol and triglycerides in the blood.
- Obesity: This is having excess body fat that increases the risk of high cholesterol, high blood pressure, diabetes and inflammation.
- Inflammation: This is a response of the immune system to injury or infection. Chronic inflammation can damage the inner lining of the arteries and promote plaque formation.
- Age: As people get older, their arteries tend to become stiffer and thicker due to wear and tear.
- Family history: People who have close relatives with atherosclerosis or its complications may have a genetic predisposition to develop the condition.
Atherosclerosis often does not cause any symptoms until it severely narrowed or blocked an artery. Therefore, it is important to get regular check-ups and screenings for risk factors such as high cholesterol, high blood pressure, diabetes, and smoking. A doctor may also perform tests such as:
- Ankle-brachial index: This measures the ratio of blood pressure in the ankle to blood pressure in the arm. A low ratio indicates reduced blood flow in the legs due to PAD.
- Lipid profile: This measures the levels of cholesterol, triglycerides, HDL and LDL in
the blood. High levels of LDL and triglycerides and low levels of HDL indicate a higher risk of atherosclerosis.
- Blood glucose: This measures the level of glucose in the blood. High blood glucose indicates diabetes or prediabetes, which increase the risk of atherosclerosis.
- Stress test: This involves exercising on a treadmill or a bike while the heart rate, blood pressure and electrocardiogram (ECG) are monitored. This can reveal signs of reduced blood flow to the heart due to coronary artery disease.
- Doppler ultrasound: This uses sound waves to create images of the blood flow in the arteries. This can show the degree of narrowing or blockage in the arteries due to plaque.
- Electrocardiogram (ECG or EKG): This records the electrical activity of the heart. This can detect abnormal rhythms or signs of damage to the heart muscle due to a heart attack or angina.
- Angiogram: This involves injecting a dye into the arteries and taking X-ray images. This can show the location and extent of plaque buildup in the arteries.
How to Treat Atherosclerosis
The treatment of atherosclerosis depends on the severity and location of the plaque, as well as the presence of symptoms and complications. The main goals of treatment are to prevent plaque from growing or rupturing, to restore blood flow to the affected organs and tissues, and to reduce the risk of future heart attacks, strokes or other problems. The treatment options include:
- Lifestyle changes: These include eating a healthy diet that is low in saturated and trans fats, salt and sugar, and high in fruits, vegetables, whole grains, lean proteins and healthy fats. Regular physical activity that is appropriate for one's age and health condition can also help lower cholesterol, blood pressure, blood glucose and body weight. Quitting smoking and limiting alcohol intake can also improve the health of the arteries and the heart.
- Medications: These include drugs that lower cholesterol (such as statins), blood pressure (such as ACE inhibitors, calcium channel blockers or diuretics), blood glucose (such as metformin or insulin) or blood clotting (such as aspirin or clopidogrel). These drugs can help prevent plaque from growing or rupturing, reduce inflammation and improve blood flow.
- Procedures: These include minimally invasive or surgical interventions that aim to open up or bypass blocked arteries. Examples are:
- Angioplasty and stent placement: This involves inserting a thin tube (catheter) with a balloon at its tip into an artery and inflating it to compress the plague against the artery wall. A metal mesh tube (stent) may then be inserted to keep the artery open.
- Endarterectomy: This involves surgically removing plaque from the inner lining of an artery, usually in the carotid or peripheral arteries.
- Bypass surgery: This involves grafting a healthy blood vessel from another part of the body to create a detour around a blocked artery, usually in the coronary or peripheral arteries.
Atherosclerosis is a serious condition that can have life-threatening consequences if left untreated. However, with proper diagnosis, treatment and prevention, it is possible to slow down its progression and reduce its complications. By adopting a healthy lifestyle and following medical advice, one can lower their risk of developing atherosclerosis and improve their quality of life.
Sources
- Debbo Africa: https://debbo.africa
- Mayo Clinic. Arteriosclerosis / atherosclerosis - Symptoms and causes. https://www.mayoclinic.org/diseases-conditions/arteriosclerosis-atherosclerosis/symptoms-causes/syc-20350569
- American Heart Association. What is Atherosclerosis? https://www.heart.org/en/health-topics/cholesterol/about-cholesterol/atherosclerosis
- MSN Health. What is Arteriosclerosis atherosclerosis and its possible symptoms, causes, risk and prevention methods? https://www.msn.com/en-us/health/condition/Arteriosclerosis-atherosclerosis/hp-Arteriosclerosis-atherosclerosis?source=conditioncdx