Evaluating Carotid Plaque Stiffness with Ultrasound 2D Shear-Wave Elastography in Patients Undergoing Coronary Artery Bypass Grafting

Background: Coronary and carotid artery diseases are manifestations of a systemic atherosclerotic process, often coexisting in patients affected by both conditions. This association emphasizes the importance of evaluating both coronary and carotid atherosclerosis in high-risk individuals. Ultrasound 2D shear-wave elastography (2D-SWE) has shown promise as a noninvasive technique for assessing carotid plaque stiffness. This prospective pilot study aimed to assess carotid plaque stiffness in patients undergoing coronary artery bypass grafting (CABG) and those not scheduled for the procedure as a control group. Methods: 32 patients (17 CABG and 15 controls) were recruited, collectively presenting 43 carotid plaques. Bilateral carotid ultrasound was performed using a high-resolution linear transducer. Plaque stiffness was quantified via 2D-SWE, expressed in shear-wave velocity (SWV, m/s) and Young’s modulus (YM, kPa). Plaque characteristics, including GSM, were quantified. Intra-observer reproducibility was evaluated with intraclass correlation coefficients (ICCs) and Bland–Altman plots. Statistical differences and correlations were assessed using Mann–Whitney U and Spearman’s correlation tests. Results: Carotid plaques in the CABG group exhibited significantly lower stiffness compared to controls (median stiffness SWV: 3.64 m/s vs. 4.91 m/s, p < 0.0001; YM: 20.96 kPa vs. 72.54 kPa, p < 0.0001). ICCs demonstrated excellent reproducibility for stiffness measurements (SWV: ICC = 0.992; YM: ICC = 0.992), with minimal bias in measurements. A positive correlation was observed between 2D-SWE and GSM values (SWV: r = 0.343, p = 0.024; YM: r = 0.340, p = 0.026). Conclusions: Ultrasound 2D-SWE has shown promise as a reliable tool for quantifying carotid plaque stiffness, demonstrating high reproducibility and a significant correlation with GSM. The observed reduction in plaque stiffness among CABG patients highlights its potential as a valuable parameter for identifying high-risk plaques and assessing cerebrovascular risk in patients undergoing CABG.