Evaluation of Plaque Stabilization by Fluvastatin with Carotid Intima- Medial Elasticity Measured by a Transcutaneous Ultrasonic-Based Tissue Characterization System

• Published in: Journal of Atherosclerosis and Thrombosis Vol. 16; no. 5; pp. 662 - 673
• Main Authors: Yamagishi, Toshio, Kato, Makoto, Koiwa, Yoshiro, Omata, Ken, Hasegawa, Hideyuki, Kanai, Hiroshi
• Format: Journal Article
• Language: English
• Published: Japan Japan Atherosclerosis Society 01-10-2009
• Subjects: Adult; Aged; Atherosclerosis - pathology; Carotid Arteries - diagnostic imaging; Carotid Arteries - drug effects; Carotid artery; Case-Control Studies; Drug Evaluation; Echo; Elasticity; Fatty Acids, Monounsaturated - pharmacology; Fluvastatin; Humans; Hydroxymethylglutaryl-CoA Reductase Inhibitors - pharmacology; Indoles - pharmacology; Middle Aged; Statin; Tunica Intima - diagnostic imaging; Tunica Intima - drug effects; Ultrasonography
• ISSN: 1340-3478; 1880-3873
• DOI: 10.5551/jat.1438

Aim: As an approach to tissue characterization, we attempted to classify in vivo carotid plaque tissues in terms of arterial wall elasticity instead of echogenicity on B-mode scanning and investigated whether the effect of fluvastatin on carotid elasticity can be detected in hypercholesterolemic patients. Methods: In 170 subjects, simultaneous measurements of intima-media thickness (IMT) and elastic modulus in the circumferential direction (Eθ) were performed using a new transcutaneous high-resolution Doppler technique. Results: From the observation of various tissues, an elasticity library was obtained as follows: lipid core, 22±15 kPa; calcification, 674±384 kPa; lipid core- and calcification-free plaques, 173±69 kPa; smooth muscle, 104±32 kPa; blood clot, 85±68 kPa; fibrosis, 273±173 kPa. The effect of fluvastatin (30 mg/day, n=62) was assessed over 12 months using the elasticity distribution and serum markers. The statin reduced low-density lipoprotein cholesterol, high-sensitivity CRP, mean IMT and mean Eθ, and increased nitrite/nitrate. In the max IMT ≥1.1 mm group, both Eθ and IMT decreased significantly. On the other hand, in the max IMT <1.1 mm group, Eθ but not IMT decreased significantly. The histogram of the subgroups showing increased Eθ with max IMT≥1.1 mm revealed a decrease in areas corresponding to Eθ of 20200 kPa (lipid/smooth muscle-rich tissue) and an increase in relatively hardened areas of <250 kPa (collagen fibers). Conclusion: Non-invasive echographic carotid arterial elasticity measurement is useful for the classification of atherosclerotic plaques and evaluation of chronological and histopathological changes.