Carotid Artery Atherosclerosis and Ischemic Stroke

Pathophysiological Mechanisms

• The American College of Cardiology suggests that atheroma in the carotid arteries can cause occlusion of the middle cerebral artery through several established mechanisms, including embolism, atheroembolism, and thrombotic occlusion with propagation 1, 2, 4
• The formation of a thrombus over an atherosclerotic plaque in the carotid artery can embolize distally to the middle cerebral artery, which is the most common mechanism of cerebral ischemia related to carotid disease 1, 2, 4
• Atheroembolism, where fragments of atherosclerotic material break off and occlude distal cerebral arteries, is a relevant mechanism, particularly in plaques with a lipid-rich necrotic core and intraplaque hemorrhage 1, 2, 4, 5

Clinical and Epidemiological Evidence

• The European Heart Journal reports that carotid artery atherosclerosis is responsible for approximately 20% of acute ischemic strokes 3
• In patients with symptomatic carotid stenosis of 70%, the stroke rate was 24% at 18 months, according to the American College of Cardiology 1, 2, 6
• The American College of Cardiology also notes that the presence of carotid stenosis >50% is the strongest predictor of new vascular events after an ischemic stroke 5

Diagnostic Considerations

• The European Heart Journal suggests that determining the mechanism of ischemic stroke in the middle cerebral artery territory is crucial, as it guides secondary prevention strategies 3
• The American College of Cardiology recommends that evaluation should include complete vascular studies, brain imaging, and cardiac evaluation to determine the primary mechanism 7