What is Atherosclerosis?
Atherosclerosis derives its name from the Greek words for "gruel" (athero) and "hardening" (sclerosis). It primarily affects medium and large arteries throughout the body.
The disease begins in the intima, the innermost lining of the artery. As plaque accumulates, the artery wall thickens and loses its elasticity. While it is often considered a "disease of the elderly," the process actually begins as early as childhood, with "fatty streaks" appearing in the arteries of teenagers. It typically remains "silent" or asymptomatic for decades until an artery is blocked by at least 70% or a plaque suddenly ruptures.
Causes of Atherosclerosis
Atherosclerosis is currently understood as a chronic inflammatory response to "injury" of the artery's lining (the endothelium).
The Process of Plaque Formation:
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Endothelial Injury: Factors like high blood pressure, smoking, or high blood sugar damage the delicate inner lining of the artery.
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Cholesterol Entry: Low-density lipoprotein (LDL or "bad") cholesterol enters the damaged wall and becomes "oxidized" (modified).
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Immune Response: Your body’s white blood cells (macrophages) rush to the site to gobble up the modified cholesterol.
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Foam Cell Creation: These cells become so full of fat that they look like foam under a microscope. As they die, they leave behind a fatty "necrotic core."
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Fibrous Cap: To protect the artery, your body builds a fibrous cap over this fatty core. If this cap is thick, the plaque is "stable." If it is thin, the plaque is "vulnerable" and prone to rupture.
Risk Factors:
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Non-Modifiable: Advancing age, male sex (though risk increases for women after menopause), and a family history of early heart disease.
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Modifiable: Smoking (the single most important risk factor), high blood pressure, diabetes, high LDL cholesterol, obesity, and a sedentary lifestyle.
Symptoms of Atherosclerosis
Atherosclerosis is a "silent killer" because symptoms rarely appear until blood flow to an organ is severely restricted. Symptoms depend entirely on which arteries are affected:
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Heart (Coronary Arteries): Chest pain or pressure (angina), shortness of breath, or a sudden heart attack.
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Brain (Carotid/Cerebral Arteries): Sudden numbness or weakness in limbs, facial drooping, difficulty speaking, or a stroke.
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Legs (Peripheral Arteries): Pain or cramping in the calves or thighs while walking (claudication), coldness in the lower leg, or non-healing sores on the toes.
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Kidneys (Renal Arteries): High blood pressure that is difficult to control or declining kidney function.
Diagnosis of Atherosclerosis
Doctors use a combination of physical exams, blood work, and advanced imaging to detect plaque and assess its impact.
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Physical Exam: Checking for "bruits" (whooshing sounds heard via stethoscope over an artery) or diminished pulses in the legs.
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Blood Tests: Measuring cholesterol (LDL, HDL, triglycerides), blood sugar (A1c), and inflammatory markers like C-reactive protein (CRP).
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Ankle-Brachial Index (ABI): A simple test comparing blood pressure in the ankle to the arm to screen for leg artery disease.
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Coronary Calcium Scan: A specialized CT scan that identifies and measures the amount of calcium in your heart arteries.
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Angiography: An invasive procedure where dye is injected into the arteries to see the exact location and severity of blockages under X-ray.
Treatment of Atherosclerosis
Treatment focuses on stabilizing existing plaques, preventing new ones from forming, and restoring blood flow if necessary.
Lifestyle Modifications: The foundation of all treatment is a heart-healthy diet (like the Mediterranean diet), regular aerobic exercise (150 minutes per week), and absolute smoking cessation.
Medications:
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Statins: These are the gold standard. They lower LDL cholesterol and have a unique "plaque-stabilizing" effect that prevents ruptures.
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Antiplatelets: Low-dose aspirin or other medications prevent blood clots from forming on top of plaques.
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Blood Pressure Meds: ACE inhibitors or beta-blockers reduce the mechanical stress on the artery walls.
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Newer Lipid Drugs: PCSK9 inhibitors or twice-yearly injections (Inclisiran) are used for patients who need aggressive cholesterol lowering.
Procedures:
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Angioplasty and Stenting: A tiny balloon is used to open the artery, and a mesh tube (stent) is left behind to keep it open.
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Bypass Surgery: A healthy blood vessel is taken from another part of the body to "bypass" or go around the blocked segment.
Prevention of Atherosclerosis
Atherosclerosis is a progressive but highly modifiable disease. Research shows that aggressive treatment can actually lead to plaque regression (the shrinking of plaques).
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Know Your Numbers: Regularly monitor your blood pressure, cholesterol, and blood sugar.
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Lower LDL Early: The longer your LDL is low, the less plaque you will accumulate over your lifetime.
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Manage Stress: Chronic stress can increase inflammation, which accelerates plaque growth.
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Heart-Healthy Diet: Focus on whole grains, fruits, vegetables, and healthy fats while eliminating trans fats and reducing refined sugars.
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Movement: Aim to reduce sedentary time; even short walks can improve endothelial function.
