[Biology Class Notes] on Arteriosclerosis Pdf

Arteriosclerosis affects is a disease or one might call it to be a condition that contributes to many diseases related to the heart. The function of the heart which is a network of blood vessels and at the center of the circulatory system is actually to pump blood to all the organs of the body. The pumped blood carries oxygen and many important nutrients that aid in the proper functioning of all the body parts. The vehicles which carry the blood away from the heart with oxygen-rich blood and the blood containing less oxygen from the other body parts to the heart ventricles are the arteries. And when these arteries become thick and stiff due to many factors it leads to a condition called arteriosclerosis. Arteriosclerosis definition can be stated as the hardening and thickening of arteries walls that leads to restriction of blood flow.  

Atherosclerosis

Arteriosclerosis is one of many conditions that occur under the umbrella of Atherosclerosis. Atherosclerosis can develop over time due to arteriosclerosis and this condition may lead to many heart diseases or cardiovascular diseases, strokes, internal bleeding that can be life-threatening, aneurysm, chronic kidney diseases and circulation problems in the limbs. Atherosclerosis is also referred to as arteriosclerosis or arteriosclerotic cardiovascular disease. Let us further understand the meaning of Atherosclerosis, Atherosclerosis causes, diagnosis, symptoms, risk factors and its treatment.

Atherosclerosis Meaning 

The Atherosclerosis definition states that atherosclerosis is the buildup of plaque due to substances like cholesterol and other fat matter in the artery wall and sclerosis means abnormal hardening of the artery wall due to it which blocks the blood flow since the arteries become narrow. And since the plaque formation is prominent in this condition is called atherosclerosis or plaque atherosclerosis.  

Atherosclerosis Causes, Diagnosis and Symptoms

This condition often occurs in the later stages of life, the causes of atherosclerosis are the build-up of so many factors.

Causes

1. High Cholesterol Levels – Cholesterol is a yellowish, crystalline, waxy solid substance that is naturally found in the body and is good at normal levels. When the cholesterol levels in the body increase due to external sources like consumption of animal products that contain trans fats. This results in an increase in the amount of solid substance that starts adhering to the walls of the arteries and making it stiff that blocks the flow. 

2. Dietary Intake – The increased levels of cholesterol in the body is mainly due to the diet we follow in our daily lives. Any types of food that have saturated fats and trans fats contribute to increased cholesterol levels. Such foods that increase cholesterol are full-fat dairy products, baked cookies, pizza, fast foods, crackers, bacon, and other animal meats and even microwave popcorn, cheese and full-fat yoghurt. Such food should be avoided as theory is doing more harm. 

3. High Blood Pressure – When the arteries are blocked in this condition, the blood pressure increases due to the narrow pathway and that too leads to atherosclerosis. One often only has a specific notion that atherosclerosis occurs only in arteries that lead to the heart but it can lead to the same symptoms even if the arteries carrying blood to other organs are blocked.

4. Obesity or Diabetes – This is also a cause of atherosclerosis. And this can be an even bigger contributing factor when the body is insulin resistant. Insulin is a common hormonal medicine for diabetic 1 and diabetic 2 type patients and instead of treating it if the body does not show healthy signs of healing it will lead to atherosclerosis and other diseases related to blocked blood flow. 

5. Inflammation – There are certain diseases like lupus, arthritis and psoriasis which causes severe inflammation and in that case too it leads to complicated stable atherosclerotic lesions because a stable plaque is formed in the affected area due to macrophages accumulation.

6. Smoking – The components of smoke like tobacco and nicotine, harms the blood cells and increases plaque formation in the blood vessels. These chemicals thicken the blood leading to the formation of clots in arteries that causes other arterial related diseases. 

7. Ageing- This is the most common cause and often one who does not lead a healthy lifestyle by eating healthy and staying active are more prone to atherosclerosis. With an unhealthy l and carefree lifestyle throughout their life, they suffer the most in old age with such life-threatening resulting disease. Along with this reason, as one grows older the arteries lose their elasticity and become weak which makes it work harder to pump the blood. Since ageing makes it difficult, homogeneous pink hyaline material in routine staining plaque builds up and leads to hyaline arteriosclerosis. 

Signs and Symptoms of Atherosclerosis

It is very important to first understand the signs of Atherosclerosis so that one can understand it is time for a proper diagnosis. Symptoms often do not appear until the arteries are almost completely blocked and one suffers from strokes and heart attacks. There are many major arteries so the symptoms can vary depending on the artery that is blocked.

1. The arteries which supply blood to the heart muscles are called coronary arteries. And when these are blocked due to plaque buildup the signs which can be seen are shortness of breath, arrhythmia which is an irregular heartbeat. And angina is a more common symptom that is a throbbing pain in the upper body that includes the chest and arms which also includes an unusual pain in the jaws and neck as well. 

2. When the arteries that supply blood to the limbs, arms, legs and pelvis are blocked it leads to a sudden numbness and an insurmountable leg ache while walking and weakness in the arms, this is a carotid artery disease.

3. High blood pressure and chronic diseases, even kidney failure, are the results of the blocked arteries that deliver blood to the kidneys. 

4. The symptoms are more physical and visible when the arteries that carry blood to the brain cells are blocked. It shows signs of drooping facial muscles, which makes it hard for a person to speak. One in this case also has a hard time understanding what the other person is saying, one has trouble seeing clearly in either one or both eyes. One experiences severe
   headache and in serious cases also leads to paralysis which contributes to cerebral atherosclerosis. 

Diagnosis

1. Blood Tests – as one age one needs to have regular body checkups and blood tests is the most common of them. Through the blood tests, one can clearly see the cholesterol levels in the blood and bodily risks. If higher levels of cholesterol levels are seen in the blood test then the risk of it can be diagnosed through various tests. 

2. Mra (Magnetic Resonance Angiography) – a computed tomography technique that creates pictures of the large arteries in your body through which one can clearly see the changes in the arteries from their natural state.

3. Abi (Ankle-Brachial Index)- helpful in determining the carotid artery disease, the blood pressure in each limb is checked and compared to look for possible blockages that are restricting the blood flow.

4. Chest X-ray – also a cardiac angiogram. Diagnosed after a radioactive dye is injected into the heart arteries. The dye helps in distinguishing the cholesterol from the blood in the arteries and the rays can clearly capture it.

5. Electrocardiogram – that is also popularly known as ECG or EKG. The diagnosis, in this case, is done through the measurement of electrical activity in the heart. It helps to look for any areas of decreased blood flow and this is a result of plaque build-up that can be confirmed. 

6. Doppler Ultrasound- In this diagnostic test sound waves are used which creates a picture of the arteries in any part of the body that one intends to and it clearly shows if there is a blockage or not.

7. Stress Test – this is done when one is engaged in an active physical activity of some sort like running on a treadmill or doing any cardio exercises even while cycling on a stationary bike which tests the heart rate and blood pressure. It is called the exercise tolerance test, so this can determine whether the heart is healthy or not. One can determine if the person’s heartbeat returns to normal quickly during the cool-down exercises which is one of the diagnoses.  

Complications of Arteriosclerosis

1. The main risks often pertain to the heart like it may cause heart failure, heart attack, abnormal heart rhythm, stroke and even death.

2. Kidney diseases due to renal arteries blockage.

3. Peripheral artery disease due to circulation problems in the lower body parts because of narrowing of arteries due to plaque formation and build-up over time.

4. Transient ischemic attack (TIA) or stroke due to carotid artery diseases.

5. Aneurysms is a bulge in the artery walls anywhere in the body due to prolonged and untreated atherosclerosis. 

6. If the bulge is created because of complicated atherosclerosis and it bursts due to any reason then cholesterol spills into the blood reaching other organs and arteries as well. The burst also leads to internal bleeding that can be life-threatening. This leakage is often very slow so it is difficult to even diagnose. 

Risk Factors Associated with Atherosclerosis

The risk factors are those conditions in which an individual becomes complacent and makes it a habit even after awareness of the possible damage that it may lead to.

1. Abdominal Obesity- which is a condition also called spare tire, due to deposited fats and high levels of cholesterol the abdomen region becomes like a tire that should be a sign to recognize the risk it contains and change your ways of living.

2. Stress- It is also a risk factor that will increase the chances of suffering from arteriosclerosis as when stressed people often tend to eat more and more often they gravitate to fat-containing foods that will further increase cholesterol levels. 

3. Diabetes- When one is already suffering from diabetes the risk for atherosclerosis increases and it further increases if there is insulin resistance body type.

4. Inactive Lifestyles- with no proper exercise on a regular basis at least five times a week, make one lazy and stay in the lump which just does not activate the pumping of blood that over time due to lack of exercise loses elasticity and becomes hard even at an earlier age than expected.

5. High Cholesterol- the cholesterol levels when increased is the main cause for atherosclerosis and definitely if it is very high the risk is higher.

6. Drinking and Smoking- alcohol and cigarettes have chemicals that do not contribute to the healthy state of the body and obviously only encourages and enhances the plaque build-up which increases the risk of having atherosclerosis.

7. Sleep Apnea- It is seen that when people suffer from obstructive sleep apnea which is often called OSA the chances of coronary artery disease increases that is a consequence of atherosclerosis.

8. High Blood Pressure- high blood pressure is clearly due to the narrowed arteries and hardening because of cholesterol and fat plaques is a certain risk factor for arteriosclerosis.

9. Improper Diet- this includes having unhealthy food that does not help in maintaining cholesterol levels and only increases it due to the fats, sugar and trans fats containing food. 

Treatment of Atherosclerosis

The treatments are usually preferred when the risk is very high and it is doctor recommended as they are aggressive and often have high chances of complicated consequences even post-treatment.

1. Bypass Surgery- also known as Coronary artery bypass surgery or CABG. It takes another healthy artery from the body mostly from the limbs and with it goes
   around the blocked segment. It is very common also to treat diabetes and survival chances also increase. 

2. Endarterectomy- The arteries in the neck are used in this procedure to remove plaques from the walls of the arteries.

3. Angiography and Stenting– in angioplasty a balloon tip with a catheter is used to remove blockages that are visible through x-rays. This process helps in easing the symptoms but one is not risk-free from heart attacks and strokes.

4. Fibrinolytic Therapy- substances like eminase, retavase, streptase etc which are also called thrombolytic drugs are used in this procedure that helps dissolves the clots formed due to the plaques by activating the plasminogen. 

5. Medication and Drugs Administration- This method of treatment can be adopted when the severity is less and it will also reduce high cholesterol and high blood pressure. Increasing survival chances with lowering the risk of heart attacks. 

6. Lifestyle Changes and Improvements- One can slow and stop the plaque build-up by making conscious decisions and changing the lifestyle and living habits. Having a proper diet with less sugar and fats, checking and maintaining healthy cholesterol and blood sugar levels, exercising regularly and maintaining a healthy weight are the initial ways one can make changes in. 

Conclusion

Atherosclerosis or arteriosclerosis is common with age but one can slow down the process and delay the risks surrounding it by taking preventive measures. Taking one step at a time and making small changes like quitting smoking and drinking, eating healthy and staying active are some ways to start living a healthy life. It is a very common phrase that says prevention is better than cure, so instead of waiting till later years to be affected by atherosclerosis and suffer from strokes and heart attacks one can start early even from a young age and take care of health to have a better old-age.