Predictors of surface disruption with MR imaging in asymptomatic carotid artery stenosis.
OBJECTIVE
Surface disruption, either ulceration or fibrous cap rupture, has been identified as a key feature of the unstable atherosclerotic plaque. In this prospective observational study, we sought to determine the characteristics of the carotid lesion that predict the development of new surface disruption.


METHODS
One hundred eight asymptomatic individuals with 50%-79% carotid stenosis underwent carotid MR imaging at baseline and at 3 years. Multicontrast imaging criteria were used to determine the presence or absence of calcification, LRNC, intraplaque hemorrhage, and surface disruption. Volume measurements of plaque morphology and the LRNC and calcification, when present, were collected.


RESULTS
At baseline, 21.3% (23/108) of participants were identified with a surface disruption. After 3 years, 9 (10.6%) of the remaining 85 individuals without disruption at baseline developed a new surface disruption during follow-up. Among all baseline variables associated with new surface disruption during regression analysis, the proportion of wall volume occupied by the LRNC (percentage LRNC volume; OR per 5% increase, 2.6; 95% CI, 1.5-4.6) was the strongest classifier (AUC = 0.95) during ROC analysis. New surface disruption was associated with a significant increase in percentage LRNC volume (1.7 +/- 2.0% per year, P = .035).


CONCLUSIONS
This prospective investigation of asymptomatic individuals with 50%-79% stenosis provides compelling evidence that LRNC size may govern the risk of future surface disruption. Identification of carotid plaques in danger of developing new surface disruption may prove clinically valuable for preventing the transition from stable to unstable atherosclerotic disease.
Underhill
H R
HR
Department of Radiology, University of Washington, Seattle, WA 98109, USA.
Yuan
C
C
Yarnykh
V L
VL
Chu
B
B
Oikawa
M
M
Dong
L
L
Polissar
N L
NL
Garden
G A
GA
Cramer
S C
SC
Hatsukami
T S
TS
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002114:Calcinosis / Q000453:epidemiology / Q000473:pathology*; D002339:Carotid Arteries / Q000473:pathology*; D016893:Carotid Stenosis / Q000453:epidemiology / Q000473:pathology*; D002543:Cerebral Hemorrhage / Q000453:epidemiology / Q000473:pathology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012307:Risk Factors; D012720:Severity of Illness Index