Background-High-resolution MRI has been shown to be capable of distinguishing intact, thick fibrous caps from thin and ruptured caps in human carotid atherosclerosis in vivo. The aim of this study was to determine whether MRI identification of fibrous cap thinning or rupture is associated with a history of recent transient ischemic attack (TIA) or stroke. Methods and Results-Fifty-three consecutive patients (mean age, 71 years; 49 male) scheduled for carotid endarterectomy were recruited after obtaining informed consent. Twenty-eight subjects had a recent history of TIA or stroke on the side appropriate to the index carotid lesion, and 25 were asymptomatic. Preoperative carotid MRI was performed in a 1.5-T GE Signa scanner that generated T 1 -, PD-, and T 2 -weighted and three-dimensional time-of-flight images. Using previously reported MRI criteria, the fibrous cap was categorized as intact-thick, intact-thin, or ruptured for each carotid plaque by blinded review. There was a strong and statistically significant trend showing a higher percentage of symptomatic patients for ruptured caps (70%) compared with thick caps (9%) (Pϭ0.001 Mann-Whitney test for cap status versus symptoms). Compared with patients with thick fibrous caps, patients with ruptured caps were 23 times more likely to have had a recent TIA or stroke (95% CIϭ3, 210). Conclusions-MRI identification of a ruptured fibrous cap is highly associated with a recent history of TIA or stroke.Ongoing prospective studies will determine the predictive value fibrous cap characteristics, as visualized by MRI, for risk of subsequent ischemic events. Key Words: magnetic resonance imaging Ⅲ atherosclerosis Ⅲ carotid arteries Ⅲ stroke R upture of the fibrous cap that overlies the thrombogenic necrotic core is presently believed to play an important role in acute ischemic events, such as stroke, transient ischemic attack, myocardial infarction, and unstable angina. [1][2][3][4] Several histological studies have revealed that lesions associated with the development of ischemic symptoms typically contain a large necrotic core that is separated from the lumen by a fibrous cap that is thin or disrupted. 5,6 Because the detection of these morphological features could identify the plaques that represent a higher risk for thromboembolic complications, the development of a noninvasive method capable of assessing the state of the fibrous cap would not only improve patient stratification to medical or surgical treatment but would also provide a means of monitoring disease progression or evaluating the efficacy of therapeutic interventions.Of the clinical imaging modalities presently used to study atherosclerosis, MRI is unique because it is noninvasive, capable of identifying plaque tissue components with submillimeter resolution, able to provide quantitative measures of disease severity, and suitable for serial investigations. [7][8][9][10][11][12][13][14] Recent studies demonstrated that high-resolution MRI is capable of distinguishing intact, thick fibrous caps from thin o...

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Background Studies have documented the short-term vascular benefits of combination lipid therapy. Objective Our objective was to evaluate the long-term effects of combination lipid therapy on carotid intima-media thickness (CIMT) in patients with coronary artery disease (CAD). Methods We performed a case-control study in patients who had finished the Familial Atherosclerosis Treatment Study (FATS) and returned to usual care with statin therapy alone or had elected to participate in the 20-year FATS-Observational Study (FATS-OS) and received combination therapy with lovastatin (40 mg/day), niacin (2–3 gm/day), and colestipol (20 gm/day) for 11 years, then continued with simvastatin (10–80 mg/day) or lovastatin (40–80 mg/day) plus niacin (2–4 gm/day). After 17.8 ± 0.8 years with combination therapy and 19.0 ± 0.8 years with usual care, cholesterol levels and CIMT were collected in 43 FATS-OS patients and 26 usual care patients. Results Combination therapy group had a greater decrease in total cholesterol (-42 ± 14% vs. −31 ± 17%, p=0.008) and low density lipoprotein cholesterol (LDL-C) (-57 ± 13% vs. −38 ± 25%, p<0.001) and greater increase in high density lipoprotein cholesterol (HDL-C) (38 ± 43% vs. 15 ± 23%, p=0.02) as compared to usual care. CIMT (0.902 ± 0.164 vs. 1.056 ± 0.169 mm, p < 0.001) on intensive therapy was significantly less compared to usual care. Multivariate regression analysis (coefficient, 95% CI) showed that combination therapy (-0.13, −0.21 – −0.04, p=0.003) and on-therapy LDL-C (0.15, 0.02 – 0.28, p=0.03) were significant independent predictors of CIMT. Conclusions Prolonged combination lipid therapy is associated with greater improvements in LDL-C and HDL-C levels and less atherosclerotic burden as compared to statin therapy alone.

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