Carotid Plaque Area

Abstract

Background and Purpose— Carotid plaque area measured by ultrasound (cross-sectional area of longitudinal views of all plaques seen) was studied as a way of identifying patients at increased risk of stroke, myocardial infarction, and vascular death. Methods— Patients from an atherosclerosis prevention clinic were followed up annually for up to 5 years (mean, 2.5±1.3 years) with baseline and follow-up measurements recorded. Plaque area progression (or regression) was defined as an increase (or decrease) of ≥0.05 cm ² from baseline. Results— Carotid plaque areas from 1686 patients were categorized into 4 quartile ranges: 0.00 to 0.11 cm ² (n=422), 0.12 to 0.45 cm ² (n=424), 0.46 to 1.18 cm ² (n=421), and 1.19 to 6.73 cm ² (n=419). The combined 5-year risk of stroke, myocardial infarction, and vascular death increased by quartile of plaque area: 5.6%, 10.7%, 13.9%, and 19.5%, respectively ( P P =0.003). Conclusions— Carotid plaque area and progression of plaque identified high-risk patients. Plaque measurement may be useful for targeting preventive therapy and evaluating new treatments and response to therapy and may improve cost-effectiveness of secondary preventive treatment.