Intensive Lipid Therapy Lowers Plaque Lipid Content
Carotid plaque lipid content decreases significantly after one year of therapy, lasts in second year
THURSDAY, Oct. 20 (HealthDay News) -- Significant decreases are observed in carotid plaque lipids after one year of intensive lipid therapy and continue in the second year, according to a study published in the Sept. 1 issue of the Journal of the American College of Cardiology: Cardiovascular Imaging.
Xue-Qiao Zhao, M.D., from the University of Washington in Seattle, and colleagues investigated whether intensive lipid therapy affected plaque lipid content, and used high-resolution magnetic resonance imaging (MRI) to establish the change in carotid plaque morphology and composition during lipid therapy. A total of 33 patients with measureable lipid-rich necrotic core (LRNC) at baseline, coronary or carotid artery disease, apolipoprotein B ≥120 mg/dL, and lipid treatment history of less than one-year were randomized to receive atorvastatin monotherapy or atorvastatin-based combination therapies with appropriate placebos for three-years. Quantification of wall area and plaque composition was analyzed using MRI images.
The investigators identified a significant reduction in plaque lipid content after three years of therapy for all patients, with average LRNC volume decreasing from 60.4 to 37.4 mm³ and average percent LRNC (LRNC area/wall area in lipid-rich regions) decreasing from 14.2 to 7.4 percent. The decreases in percent LRNC in the first, second, and third years were 3.2 (P < 0.001), 3.0 (P = 0.005), and 0.91 percent (P = 0.2), respectively, with a similar LRNC volume pattern of changes. There was a significant decrease in the average percent wall volume in lipid-rich regions from 52.3 to 48.6 percent, which was significantly higher in slices containing LRNC than those without.
"These findings suggest a potential mechanism for plaque stabilization associated with intensive lipid therapy," the authors write.
The study was partially funded by Pfizer; the study medications were provided by Pfizer, Abbott Laboratories, and Daiichi Sankyo.