Abstract Body: Background: Cardiovascular disease (CVD) is a leading cause of morbidity and mortality worldwide, with atherosclerosis contributing significantly to its progression. Lagrangian strain imaging is a valuable noninvasive imaging tool for assessing changes in arterial wall mechanics, as associated with arterial stiffness and atherogenesis. This study explores the relationship between Lagrangian carotid strain indices and atherosclerosis.
Hypothesis: We hypothesize that in individuals with atherosclerosis, arterial wall strain should decrease with atherosclerosis as the vessel stiffens due to arterial remodeling and plaque buildup.
Methods: Radiofrequency (RF) data from the right and left common carotid arteries (CCAs) of 169 volunteers were analyzed alongside demographic information, lipid/metabolic panels, and physician-assessed carotid atherosclerosis. Using B-mode and color Doppler imaging, a sonographer segmented the near and far walls of the CCAs at end-diastole. Axial, lateral, and shear strain indices were calculated for up to two cardiac cycles. Participants were categorized into two groups: those with carotid atherosclerosis (focal thickening and/or plaque) and those without. Group comparisons were performed using the Mann-Whitney U-test, with results reported as median[IQR].
Results: Among 169 participants (60% female, aged 18–88 years, mean age 45), 25% (n=42) had carotid atherosclerosis. The carotid atherosclerosis group exhibited significantly lower maximum axial strain (25.56[16.92] vs 32.43[26.08]; p<0.001) and maximum shear strain (20.74[11.49] vs 27.50[21.72]; p=0.013), indices indicating increased arterial stiffness. Participants with atherosclerosis were significantly older (60.5[12] vs 38[21] years; p<0.001) and exhibited increased values of total cholesterol (211.5[44] vs 184[45] mg/dL; p<0.001), HDL-C (57.5[21] vs 52[20] mg/dL; p=0.040), LDL-C (134[39] vs 111[42] mg/dL; p<0.001), and hemoglobin A1c (5.6%[0.4%] vs 5.4%[0.4%]; p<0.001).
Conclusion: Ultrasound-based Lagrangian strain imaging effectively identifies arterial stiffness associated with atherosclerosis, as demonstrated by significantly decreased strain indices in participants identified with carotid atherosclerosis. However, further research with a more balanced age distribution within groups is needed for a better understanding of the effect of atherosclerosis induced stiffening when compared to arterial stiffening seen with aging.