Atherosclerosis is a condition where plaque—a sticky substance of fat, cholesterol, calcium, and other materials—builds up inside your arteries, the blood vessels carrying oxygen-rich blood from your heart. This buildup causes arteries to thicken and become less flexible, a process often called hardening. While “arteriosclerosis” is a general term for arterial hardening, atherosclerosis specifically refers to this plaque accumulation.
The Process of Plaque Buildup
Atherosclerosis begins with damage to the endothelium, the smooth inner lining of an artery, leading to an inflammatory response. Following this injury, low-density lipoprotein (LDL) cholesterol, or “bad” cholesterol, penetrates the damaged lining and accumulates in the artery wall.
The immune system sends monocytes to the site, which transform into macrophages. These macrophages consume cholesterol, becoming “foam cells.”
Foam cells, cellular debris, calcium, and fatty substances accumulate, forming an atheroma, or plaque. A fibrous cap of collagen and smooth muscle cells develops over the plaque, stabilizing it and separating it from the bloodstream.
If the plaque grows or the fibrous cap weakens, it can rupture. This exposes the plaque’s contents to the blood, triggering a blood clot (thrombus) that can obstruct blood flow, potentially leading to a heart attack or stroke.
Causes and Risk Factors
Atherosclerosis develops over many years, influenced by factors that initiate and accelerate plaque buildup. These factors are categorized as modifiable or non-modifiable, and understanding them aids in managing the condition.
Modifiable Risk Factors
High LDL cholesterol levels contribute to plaque formation by accumulating in damaged artery walls. High blood pressure (hypertension) also damages the endothelium, making arteries susceptible to plaque by creating microscopic tears that invite cholesterol deposition.
Smoking introduces toxins that injure blood vessel walls, promoting inflammation and accelerating plaque development, while also reducing HDL cholesterol. Diabetes, with its elevated blood sugar, damages blood vessels, making them prone to atherosclerosis.
Obesity, especially abdominal fat, contributes to chronic inflammation and metabolic imbalances that foster plaque growth. Lack of physical activity promotes obesity and worsens other risk factors. Diets high in saturated fats, trans fats, cholesterol, and sugar increase LDL cholesterol and inflammation, advancing the disease.
Non-Modifiable Risk Factors
Advancing age is a natural risk factor, as arteries stiffen and accumulate damage over time. Atherosclerosis often begins in childhood and progresses silently with age. Male gender is associated with an earlier risk than females, though female risk increases after menopause. A family history of early heart disease indicates a genetic predisposition to plaque buildup.
Associated Health Conditions and Symptoms
Atherosclerosis often progresses without noticeable symptoms until arterial narrowing severely restricts blood flow or a plaque ruptures. Symptoms and conditions depend on which arteries are affected. This silent progression makes early recognition challenging, emphasizing the importance of understanding its consequences.
Coronary Artery Disease (CAD)
Plaque in the coronary arteries, which supply blood to the heart, leads to coronary artery disease. Symptoms include angina (chest pain or discomfort, often triggered by activity or stress) and shortness of breath during exertion. A complete blockage, often from a ruptured plaque and blood clot, can cause a heart attack, damaging heart muscle.
Carotid Artery Disease
Plaque in the carotid arteries (neck arteries supplying the brain) can cause carotid artery disease. Reduced blood flow to the brain can lead to a transient ischemic attack (TIA), or “mini-stroke.” TIA symptoms, like sudden weakness, numbness, speech difficulty, or temporary vision loss, usually resolve quickly. A TIA is a strong warning sign of stroke risk if blood flow is severely interrupted.
Peripheral Artery Disease (PAD)
Peripheral artery disease (PAD) occurs when atherosclerosis affects arteries supplying blood to the limbs, commonly the legs. The hallmark symptom is claudication: leg pain or cramping during walking or exercise that subsides with rest, due to insufficient oxygenated blood. As PAD progresses, pain may occur at rest, and non-healing sores or ulcers can develop on the legs or feet from severe blood flow restriction.
Chronic Kidney Disease
Atherosclerosis in the renal arteries (kidney blood supply) can lead to renal artery stenosis and chronic kidney disease. Reduced blood flow impairs the kidneys’ ability to filter waste. While early symptoms may not be apparent, chronic kidney disease can cause high blood pressure, fluid retention, and fatigue as kidney function declines.
Diagnosis and Treatment Approaches
Identifying atherosclerosis involves medical assessments and specialized tests. Treatment focuses on managing existing plaque, preventing its progression, and reducing complication risk. Approaches begin with lifestyle changes and can progress to medications or procedures for advanced cases.
Diagnosis
Diagnosis often begins with a physical exam and review of medical history to assess risk factors. Blood tests measure cholesterol (LDL, HDL, triglycerides), blood sugar (for diabetes screening), and kidney function.
Non-invasive tests provide further insights. An electrocardiogram (ECG or EKG) detects past heart attacks or heart strain. Carotid artery ultrasound visualizes neck plaque and blood flow. Advanced imaging, like a CT angiogram, uses X-rays and dye to create detailed artery images, pinpointing plaque and narrowing.
Treatment
Atherosclerosis treatment involves a multi-pronged approach tailored to the individual.
Lifestyle Modifications
Adopting heart-healthy lifestyle changes is a foundational step in managing atherosclerosis. A balanced diet low in saturated fats, trans fats, cholesterol, sodium, and added sugars (e.g., Mediterranean or DASH diet) helps lower cholesterol and blood pressure. Regular physical activity (at least 30 minutes of moderate intensity most days) improves cardiovascular health and manages weight. Quitting smoking is also important, as tobacco damages arteries and accelerates plaque formation.
Medications
Medications are prescribed to control risk factors and prevent complications. Statins lower LDL cholesterol, stabilizing existing plaque and reducing its growth. Antihypertensive medications lower high blood pressure, reducing stress on arterial walls. Antiplatelet agents, like aspirin, prevent blood clots on plaque surfaces, reducing heart attack and stroke risk, especially after a rupture.
Procedures
For severe arterial narrowing or blockages that impair blood flow, medical procedures may be necessary. Angioplasty with stenting involves inserting a balloon-tipped tube to widen the artery, often followed by placing a stent to keep it open. For extensive blockage, bypass surgery creates a new blood flow route using a healthy blood vessel. These procedures restore adequate blood supply to affected organs and tissues.