Carotid Artery Disease Lecture Notes

Introduction

• Carotid Artery Disease: Atherosclerosis of carotid arteries, similar to coronary artery disease.
• Risk Factors:
  • Diabetes mellitus
  • Hyperlipidemia (LDL to HDL ratio > 3:1)
  • Smoking
  • Non-modifiable: male sex, advanced age, genetic predisposition

Relationship to Stroke

• Major Cause of Stroke:
  • 85-90% due to thrombosis (blockage)
  • 10-15% due to hemorrhage (bleeding)
• Mechanisms:
  • Embolization of carotid artery debris
  • Primary vascular occlusion (100% occlusion due to atherosclerosis)

Manifestations

• Transient Ischemic Attack (TIA): "Mini-stroke" with symptoms lasting < 24 hours
• Amaurosis Fugax: Transient monocular blindness due to retinal artery embolism
• Cerebrovascular Accident (Stroke): Symptoms lasting > 24 hours, possible irreversible damage

Management

Medical Management

• Control risk factors: diabetes, hyperlipidemia, smoking cessation
• Medications: Statins, antiplatelet drugs, anticoagulation

Surgical Management

• Carotid Endarterectomy: Gold standard surgical treatment
• Carotid Stenting: Increasingly used but less common in test scenarios

Diagnosis

• Physical Examination: Carotid artery bruit detected via auscultation
• Imaging: Duplex ultrasound to evaluate blood flow and plaque
• Additional Tests: EKG to assess for other atherosclerosis

Carotid Endarterectomy Details

• Symptomatic Patients: Surgery recommended for ≥ 70% blockage
• Asymptomatic Patients: Surgery recommended for ≥ 60% blockage
• Surgical Process:
  • Clamping of arteries
  • Removal of plaque
  • Monitored via EEG for brain function
• Complications:
  • Stroke, ischemia
  • Injury to hypoglossal or vagus nerve
  • Blood pressure instability

Contraindications

• Disabling stroke with acute loss of consciousness
• 100% occlusion
• Severe medical illnesses with reduced life expectancy

Key Points

• Carotid auscultation essential for older patients and those with risk factors
• Carotid endarterectomy tests focus on 70% blockage for symptomatic and 60% for asymptomatic patients
• Contraindications and potential complications should be carefully considered

Conclusion

• Carotid artery disease is a significant risk factor for stroke and requires careful diagnosis and management through medical and surgical means. Carotid endarterectomy remains the standard procedure for significant blockages.