Abstract 13355: Clinical Variables Correlated With MRI-assessed Carotid Plaque Neovasculature in Statin-treated Patients
Introduction: Plaque neovasculature is a major route for lipoprotein and leukocyte ingress into plaques, and has been identified as a risk factor for carotid plaque disruption. Vp, a variable derived from pharmacokinetic modeling of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI), is a histologically-validated correlate of plaque neovasculature density. Because lipid-lowering therapy has been associated with regression of neovasculature in animal models, the relationships of clinical variables and statin therapy to carotid plaque neovasculature, we sought to determine clinical correlates of carotid plaque neovasculature (as assessed by Vp) in participants on statin therapy for established cardiovascular disease.
Methods: Clinical variables and DCE-MRI scans were obtained at baseline in 98 participants in an AIM-HIGH substudy. Lengths of statin treatment ranged from <1 yr (21%), 1-5 yrs (40%) and >5 yrs (39%). Baseline LDL-C (mean± SD) was 71± 18 mg/dL, age was 62± 9 yrs, and 81% had metabolic syndrome. MR images were analyzed for Vp by expert reviewers who were blinded to all clinical and treatment-related variables. Vp values are expressed as mean± SD x10-2. Statistically significant associations with Vp were identified by Pearson or Spearman correlations, or by one-way ANOVA, as appropriate.
Results: Shorter duration of statin therapy was associated with higher Vp (<1 yr: 10.0± 4.3, 1-5 yrs: 7.6± 4.8, >5 yrs: 6.2± 4.4; P=0.01). Metabolic syndrome was associated with significantly higher Vp (8.1± 4.7 vs. 5.2± 4.1, P=0.01). Continuous clinical variables correlated with higher Vp values included body mass index (r=0.25, P=0.01) and lipoprotein(a) (r=0.26, P=0.01).
Conclusions: These results suggest that metabolic syndrome, body mass index and lipoprotein(a) are risk factors for carotid plaque neovasculature in statin-treated patients. Moreover, these results raise the possibility that statin therapy might be associated with regression of plaque neovasculature.
- © 2013 by American Heart Association, Inc.