2. • Atherosclerosis is a condition where the arteries become narrowed
and hardened due to a build up of plaque around the artery wall.
• It is also known as arteriosclerotic vascular disease.
• Initially, there are generally no symptoms.
• It can result in coronary artery disease, stroke, peripheral artery
disease, or kidney problems, depending on which arteries are
affected.
What is Atherosclerosis ?
3. What is Plaque ?
• Plaque is an abnormal accumulation of material in the inner layer of
the wall of an artery.
• The material consists of mostly macrophage cells, or debris,
containing lipids, calcium and a variable amount of fibrous connective
tissue.
• The accumulated material forms a swelling in the artery wall, which
may intrude into the channel of the artery, narrowing it and
restricting blood flow.
4. Introduction :-
• It is involved in the accumulation of cholesterol, fatty substances,
cellular waste, calcium deposits, and inflamed smooth muscle cells in
the endothelial lining of large and medium sized arteries, which
ultimately results in strokes and myocardial infarctions (MI) due to
occlusion of the vessels.
• It’s high morbidity rate is contributed by the current lifestyles that
exist, which includes in many cases no exercise and ingestion of fatty
condiments, but can include genetic factors.
5. • Plasma chemistry determines that the main molecule prevalent in
progressing this disease is known as low-density lipoprotein (LDL).
• When the endothelial lining of the arterial vessel undergoes injury,
cholesterol molecules have the ability to deposit themselves into the
lining of the vessel.
• The monocytes present become macrophages once inside the lining
of the vessel and uptake the cholesterol, which becomes oxidized
causing the macrophages to present an appearance as ‘foamy’.
• The macrophages increase the risk of plaque rupture by secreting
matrix metalloproteinases (MMP) causing the thinning of the fibrous
cap.
• Macrophages are phagocytic cells known to take in cellular debris,
wastes and modified lipoproteins.
Biochemical Role :-
6. • Macrophages contain an abundance of receptors that are in charge of
the uptake of cholesterol however only native LDL will be
phagocytized via endocytic mechanisms.
• There are several types of LDL modifications that permit cholesterol
uptake such as acetylated LDL (acLDL), oxidized LDL(oxLDL) and
aggregated LDL (agLDL).
• Macrophages can cause oxidation and cause uptake of LDL by
exocytosis of iron due to phagocytized erythrocytes.
• Foam cell formation is induced when the cholesterol removal process
becomes limited either because there is too much cholesterol in the
plasma and it overwhelms the macrophage or the cholesterol
secretion process in the macrophage is limited because there is not
enough HDL in the surroundings.
7. • Cholesterol uptake in foam cells is mediated by scavenger receptor A
and CD36 receptors. CD36 consists of a extracellular domain with
transmembrane and cytoplasmic domains.
• CD36 consists of a extracellular domain with transmembrane and
cytoplasmic domains. It is highly expressed on foam cells and has a
high affinity for ox-LDL and aids in the endocytosis of lipids and can
be influenced by various factors.
• Scavenger receptor A is also highly expressed in the macrophage and
aids in the uptake of ox-LDL.
• A voltage gated potassium channel has been investigated in the up-
regulation of SR-A expression in macrophages revealing a possible
strategy in regulating cholesterol metabolism.
9. Symptoms :-
• Chest pain or angina
• Pain in your leg, arm, and anywhere else that has a blocked artery
• Shortness of breath
• Fatigue
• Confusion, which occurs if the blockage affects circulation to your
brain
• Muscle weakness in your legs from lack of circulation
• Nausea or vomiting
• Sudden, severe headache
10. Diagnosis :-
Physical Examination
• A weakened pulse
• An aneurysm, which is an abnormal bulging or widening of an artery due to weakness of the arterial
wall
• Slow wound healing, which indicates a restricted blood flow
Tests
• A blood test to check your cholesterol levels
• A Doppler ultrasound, which uses sound waves to create a picture of the artery that shows if there’s a
blockage
• Ankle-brachial index test, which looks for a blockage in your arms or legs by comparing the blood
pressure in each limb
• An electrocardiogram (ECG), which measures the electrical activity in your heart to look for any areas
of decreased blood flow
• A stress test, or exercise tolerance test, which monitors your heart rate and blood pressure while you
exercise on a treadmill or stationary bicycle
11. Treatment :-
Medications
• Cholesterol-lowering medications, including statins and fibric acid derivatives
• Antiplatelet drugs and anticoagulants, such as aspirin, to prevent blood from clotting and clogging your
arteries
• Beta blockers or calcium channel blockers to lower your blood pressure
• Diuretics, or water pills, to help lower your blood pressure
• Angiotensin converting enzyme (ACE) inhibitors, which help prevent narrowing of your arteries
Surgery
• Bypass surgery - using a vessel to divert blood around your blocked or narrowed artery
• Thrombolytic therapy - dissolving a blood clot by injecting a drug into your affected artery
• Angioplasty - using a thin, flexible tube called a catheter and a balloon to expand your artery,
sometimes inserting a stent to leave the artery open
• Endarterectomy - surgically removing fatty deposits from your artery
• Atherectomy - removing plaque from your arteries by using a catheter with a sharp blade at one end
12. Prevention :-
• Eating a healthy diet that’s low in saturated fat and cholesterol
• Avoiding fatty foods
• Adding fish to your diet twice per week
• Exercising for 30 to 60 minutes per day, six days per week
• Quitting smoking if you’re a smoker
• Losing weight if you’re overweight or obese
• Managing stress
• Treating conditions associated with atherosclerosis, such as
hypertension, high cholesterol, and diabetes