Irregularity of Carotid Plaque Surface Predicts Subsequent Vascular Event: A MRI Study.

Background The relationship between plaque compositions and irregular plaque surface and its predictive value for vascular events (VEs) are unknown. Purpose To investigate the relationship between irregular carotid plaque surface and plaque compositional features and its predictive values for future VEs utilizing magnetic resonance (MR) vessel wall imaging. Study Type Prospective study. Population In total, 140 patients with cerebrovascular symptoms were recruited. Field Strength/Sequence 3T, black blood T-1-weighted, black blood T-2-weighted, 3D time-of-flight, magnetization-prepared rapid acquisition gradient echo (MP-RAGE), and 3D motion sensitized driven equilibrium rapid gradient echo (MERGE). Assessment The carotid artery stenosis and maximum wall thickness (Max WT) were measured. The presence/absence of irregular carotid plaque surface, calcification, lipid-rich necrotic core (LRNC), intraplaque hemorrhage (IPH), and fibrous cap rupture was determined. After baseline examination, all patients were followed-up for at least 1 year to record the VEs. Statistical Tests Independent t-test, Mann-Whitney U-test, Chi-square, logistic regression, and Cox regression were used. Results In total, 82 (58.6%) had irregular plaque surfaces. The carotid Max WT, stenosis, and the presence of surface calcification, LRNC and IPH were significantly associated with irregular plaque surface (all P < 0.05). After adjusted for baseline confounding factors, these associations remained statistically significant (all P < 0.05). During the median follow-up time of 12.1 months, 37 (26.4%) patients had VEs. Univariable Cox regression analysis showed that the irregular carotid plaque surface was significantly associated with subsequent VEs (hazard ratio [HR], 11.02; 95% confidence interval [CI], 2.65-45.85; P = 0.001). After adjusted for baseline and follow-up confounding factors, this association remained statistically significant (HR, 13.03; 95% CI, 1.71-99.42, P = 0.013). After further adjusted for intracranial stenosis, this association also remained statistically significant (HR, 12.57; 95% CI, 1.63-96.83, P = 0.015). Data Conclusion The morphology of carotid atherosclerotic plaque surface determined by MR vessel wall imaging, particularly irregular plaque surface, is an independent predictor for subsequent vascular events. Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2020.