Work

Carotid plaque characteristics in the CREST-2 trial

Year: 2024

Type: article

Abstract: Background The modest stroke-prevention from surgery for asymptomatic carotid disease has prompted a search for predictors that may improve risk-stratification beyond luminal stenosis. Plaque disruption and atheroembolization are associated with unique anatomic and histologic changes. The Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) collects information on duplex ultrasound (DUS) plaque biomarkers with the goal of evaluating their relationship to periprocedural and long-term risk of stroke. In this study, we examine the reliability with which carotid plaque features can be measured from DUS images, and report baseline carotid DUS-derived stenosis and plaque features using semi-automated digital image analysis of patients enrolled in CREST-2. Methods We studied the first 503 patients in CREST-2. Patients underwent standardized carotid DUS evaluation pre-enrollment. B-mode images were linearly scaled to normalize brightness. Plaques were manually outlined. Dedicated software automatically measured the longitudinal sectional area (mm 2 ), grayscale median (GSM), Gray-Weale classification, 4), and tissue composition (mm 2 ) of intraplaque hemorrhage (IPH), lipid, fibrous tissue, muscle, and calcium. We present the mean, standard deviation (SD), median, interquartile range, minimum and maximum range, and proportions of carotid peak systolic velocities (PSV) and plaque morphologic features. We tested for autocorrelation among plaque features and computed the proportion of potentially unstable plaques in the cohort. Reliability of the image analysis techniques was tested in 100 patients using Bland-Altman plots and intra- and inter-class correlation coefficients. Results Most patients were male (58.4%), older (mean age 69.3 years), white (87.5%), and had a PSV ≥230 cm/second (98.6%); the 1.4% with a PSV <230 cm/second were enrolled based on catheter angiography. Plaques in this study were large, mean longitudinal-sectional area 62±37 mm 2 (range 6.2–256.5 mm 2 ). The mean GSM was 58±30 (unitless, range 0–168) and Gray-Weale classification was 3.5±0.9 (range, 1–5). The mean areas of tissue types (mm 2 ) were IPH 5.3±8.9, lipid 9.3±8.6, fibrous tissue 10±10, muscle 17±12, and calcium 1.6±4.1. The PSV of patients showed poor correlation with plaque features. The proportion of plaques with a GSM ≤35 was 22.8%, IPH ≥5 mm 2 was 30.0%, and LRNC ≥40% was 3.0% of the cohort. Plaque measurements could be performed with high reliability with good inter- and intra-observer correlations. Conclusions Site-generated, core lab-interpreted ultrasonography provides a reliable way of characterizing carotid plaque morphologic features across studies performed at many CREST-2 sites. The initial cohort of patients randomized in CREST-2 had heterogeneity of plaque features despite causing high-grade stenosis. Completion of the trial will provide an opportunity to assess whether plaque heterogeneity interacts with response to revascularization and medical management.

Source: JVS-Vascular Insights

DOI: 10.1016/j.jvsvi.2024.100134