How serious is a mild narrowing of the carotid artery?

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Q. What is the significance of mild narrowing of the carotid artery detected by an ultrasound? I have never had any symptoms of stroke.

A. "Mild" narrowing ranges from 15% to 49% blockage of the artery. Over time, this narrowing can progress and lead to a stroke. Even if it doesn't progress, mild narrowing is a sign of early blood vessel disease and calls for preventive measures.

The presence of atherosclerotic plaque in the carotid artery is a predictor for future risk of cardiovascular disease. But when the amount is not severe, the focus is on drug treatment, not surgery. Progression is associated with a number of factors, including diabetes and smoking. The initial amount of blockage is important, too. Cholesterol-lowering medications, aspirin, and blood pressure control (optimally less than 130/80 mm Hg) are recommended for all men with any significant carotid artery disease. Although the narrowing can worsen over time, there are no recommendations to routinely repeat testing in men who have no symptoms.

Most strokes in men with carotid narrowing are preceded by symptoms common to transient ischemic attacks (ministrokes), such as facial or arm numbness, speech problems, or weakness on one side of the body. It is important to address these symptoms even if they are brief and improve without treatment.

— by William Kormos, M.D.
Editor in Chief, Harvard Men's Health Watch