- Atherosclerosis (Primary Cause):
- The buildup of plaque narrows the carotid arteries, reducing blood flow to the brain.
- Plaque can also become unstable, rupture, and form blood clots that block the artery or travel to the brain.
- Risk Factors for Atherosclerosis (and thus Carotid Artery Disease):
- High Blood Pressure (Hypertension): Damages the inner lining of arteries, making them more susceptible to plaque buildup.
- High Cholesterol (Hyperlipidemia): High levels of LDL ("bad") cholesterol contribute directly to plaque formation.
- Smoking: Significantly accelerates atherosclerosis by damaging blood vessel walls, increasing blood clotting, and lowering beneficial HDL cholesterol. It is one of the strongest risk factors.
- Diabetes Mellitus: High blood sugar damages blood vessels throughout the body, including the carotid arteries, and promotes atherosclerosis.
- Age: The risk of carotid artery disease increases significantly with age, particularly after 50.
- Obesity: Contributes to other risk factors like diabetes, high blood pressure, and high cholesterol.
- Lack of Physical Activity: Sedentary lifestyle is associated with higher risk.
- Family History: A family history of atherosclerosis, carotid artery disease, heart disease, or stroke increases an individual's risk.
- Other Less Common Causes:
- Fibromuscular Dysplasia: A non-inflammatory arterial disorder that causes abnormal cell growth in the artery walls.
- Vasculitis: Inflammation of blood vessels (e.g., Takayasu's arteritis).
- Trauma: Injury to the neck that damages the carotid artery.
- No Symptoms (Asymptomatic): Many people with carotid artery disease, especially in the early stages, have no noticeable symptoms. This is why screening is important for high-risk individuals.
- Symptoms of Transient Ischemic Attack (TIA - "Mini-Stroke"):
- A TIA is a temporary interruption of blood flow to part of the brain, causing stroke-like symptoms that last only a few minutes to an hour and resolve completely without permanent damage.
- TIAs are a strong warning sign of an impending stroke and require immediate medical attention.
- Symptoms are similar to a stroke but temporary:
- Sudden weakness or numbness on one side of the face, arm, or leg.
- Sudden difficulty speaking (dysphasia or aphasia) or understanding speech (aphasia).
- Sudden confusion.
- Sudden trouble seeing in one or both eyes (amaurosis fugax - often described as a curtain coming down over vision).
- Sudden dizziness, loss of balance, or coordination.
- Symptoms of Stroke:
- If a blood clot or plaque fragment completely blocks blood flow to a part of the brain, a stroke occurs. Stroke symptoms are similar to TIA but are persistent and cause permanent brain damage.
- Remember FAST: Face drooping, Arm weakness, Speech difficulty, Time to call emergency services.
- Bruit: A whooshing sound heard with a stethoscope over the carotid artery, indicating turbulent blood flow through a narrowed artery. Not always present, and can occur in non-significant narrowing.
- Medical History and Physical Exam: The doctor will inquire about risk factors, symptoms (especially TIA or stroke symptoms), and family history. The exam involves listening for a carotid bruit, checking blood pressure, and performing a neurological assessment.
- Carotid Duplex Ultrasound:
- The most common, non-invasive, and effective initial test.
- Uses sound waves to create images of the carotid arteries and measure blood flow velocity, which indicates the degree of narrowing (stenosis).
- CT Angiography (CTA) of the Neck:
- Uses CT scans with contrast dye to produce detailed images of the carotid arteries.
- Provides precise information about the location and severity of plaque, and is useful for surgical planning.
- MR Angiography (MRA) of the Neck:
- Similar to CTA, but uses MRI technology and contrast dye (or sometimes no contrast) to visualize the carotid arteries. It avoids radiation exposure.
- Conventional Angiography (Catheter Angiography):
- An invasive procedure that is considered the "gold standard" for detailed visualization of arteries. A catheter is inserted into an artery (usually in the groin) and contrast dye is injected to highlight the carotid arteries on X-ray.
- Less commonly used for primary diagnosis due to invasiveness, but may be performed just before or during an intervention.
- Lifestyle Modifications (Crucial for all patients):
- Smoking Cessation: Absolutely the most important step to slow or halt disease progression and reduce stroke risk.
- Healthy Diet: Low in saturated fats, trans fats, and cholesterol; rich in fruits, vegetables, whole grains.
- Regular Physical Activity: At least 150 minutes of moderate-intensity aerobic exercise per week.
- Weight Management: Achieve and maintain a healthy weight.
- Medications:
- Antiplatelet Medications:
- Aspirin: Often prescribed to prevent blood clots.
- Clopidogrel (Plavix): May be used alone or in combination with aspirin, especially after a TIA or stroke.
- Statins: (e.g., atorvastatin, rosuvastatin) To lower cholesterol, stabilize plaque, and reduce inflammation in artery walls, thereby reducing stroke risk.
- Blood Pressure Medications: To control hypertension (e.g., ACE inhibitors, ARBs, beta-blockers, diuretics) to reduce stress on artery walls.
- Diabetes Medications: To control blood sugar levels if diabetic.
- Antiplatelet Medications:
- Procedures and Surgery (for significant narrowing or symptoms):
- Carotid Endarterectomy (CEA):
- A surgical procedure where an incision is made in the neck, the carotid artery is opened, and the plaque is surgically removed.
- Considered the gold standard for symptomatic patients with significant carotid artery narrowing (typically >50-70%) and for select asymptomatic patients with very severe narrowing.
- Carotid Angioplasty and Stenting (CAS):
- A less invasive procedure where a catheter is threaded through an artery (usually in the groin) to the carotid artery. A balloon is inflated to widen the narrowed artery, and a stent (a small metal mesh tube) is often placed to keep it open.
- Often considered for patients who are not good candidates for CEA due to other medical conditions or anatomical reasons.
- Carotid Endarterectomy (CEA):