The carotid arteries are two major blood vessels located on each side of the neck, playing an important role in delivering oxygenated blood from the heart directly to the brain. This continuous supply is necessary for brain function and health. Carotid artery blockage, known as carotid artery disease or atherosclerosis, occurs when fatty deposits and other substances accumulate on the inner walls of these arteries. This buildup, called plaque, narrows the arteries and reduces blood flow to the brain.
Understanding “Normal” Carotid Artery Health
A healthy carotid artery is largely unobstructed, allowing unimpeded blood flow to the brain. Its inner lining (endothelium) remains smooth and free from significant fatty deposits. They maintain elasticity and diameter, ensuring consistent blood supply.
Significant narrowing or blockage is not normal and signals an underlying health condition. A healthy artery transports blood efficiently without notable impedance or plaque rupture risk. Substantial plaque indicates a deviation, necessitating medical attention.
How Carotid Artery Blockage Develops
Carotid artery blockage primarily develops through atherosclerosis, a gradual hardening and narrowing of arteries. This process begins when the inner lining of the artery wall becomes damaged, often due to factors like high blood pressure, high cholesterol, or smoking. Once damaged, the artery wall becomes more susceptible to the accumulation of fatty substances, cellular waste, and calcium.
Over time, these materials coalesce to form plaque, which stiffens and thickens the artery walls. As plaque grows, it progressively narrows the carotid artery’s lumen, restricting blood flow to the brain. This can significantly reduce blood supply. Risk factors include uncontrolled high blood pressure, elevated low-density lipoprotein (LDL) cholesterol, diabetes, and tobacco use.
Diagnosing and Grading Carotid Artery Blockage
Diagnostic methods assess carotid artery blockage. Carotid duplex ultrasound is a common, non-invasive procedure using sound waves to image the carotid arteries and measure blood flow. This helps visualize plaque buildup and determine narrowing.
Carotid artery blockage is graded by the percentage of arterial narrowing. It is classified as mild (less than 50% narrowing), moderate (50% to 69% narrowing), or severe (70% to 99% narrowing). 100% blockage is total occlusion. The percentage of stenosis, or narrowing, guides treatment decisions, as higher percentages correlate with an increased stroke risk.
Recognizing Symptoms and Seeking Care
Significant carotid artery blockage may not cause symptoms until narrowing becomes severe or a transient ischemic attack (TIA) or stroke occurs. A TIA, often called a “mini-stroke,” is a temporary episode of stroke-like symptoms resulting from a temporary interruption of blood flow to the brain. TIA symptoms include sudden weakness or numbness on one side, difficulty speaking or understanding speech, sudden vision changes in one eye, or dizziness.
These symptoms are often brief but warn that a stroke could occur soon. A stroke, a medical emergency, happens when blood flow to a part of the brain is interrupted or reduced, depriving brain tissue of oxygen and nutrients. Anyone experiencing sudden onset of these symptoms should seek immediate medical attention by calling emergency services.
Strategies for Management and Prevention
Management and prevention of carotid artery blockage involve lifestyle adjustments and medical interventions. Lifestyle modifications include a heart-healthy diet, regular physical activity, and maintaining a healthy weight. Quitting smoking is crucial, as tobacco use substantially increases plaque formation and progression risk.
Medications manage risk factors and prevent plaque buildup. These include statins to lower cholesterol levels and antiplatelet medications, such as aspirin, to prevent blood clots. For severe blockages or recurring symptoms, medical procedures like carotid endarterectomy (surgically removing plaque) or carotid angioplasty and stenting (widening the artery and placing a small mesh tube) restore blood flow.