The Two-Dimensional Shear Wave Elastography (2D-SWE) in Assessing Abdominal Aortic Wall Stiffness

International Journal of Biomedicine 15(4) (2025) 690-694 http://dx.doi.org/10.21103/Article15(4)_OA7 ORIGINAL ARTICLE INTERNATIONAL JOURNAL OF BIOMEDICINE Radiology The Two-Dimensional Shear Wave Elastography (2D-SWE) in Assessing Abdominal Aortic Wall Stiffness Salahaden R. Sultan1*, Lojain Alsayegh1, Hajer B. Almsaari1, Mohammad Khalil2, Abrar Alfatni1, Reham Kaifi3,4,5, Mohammed Alkharaiji6, Adel Alzahrani7, Mohammed Aslam8 Department of Radiologic Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia 2 Department of Radiology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia 3 College of Applied Medical Sciences, King Saud bin Abdulaziz University for Health Sciences, Jeddah, Saudi Arabia 4 King Abdullah International Medical Research Center, Jeddah, Saudi Arabia 5 Medical Imaging Department, Ministry of the National Guard—Health Affairs, Jeddah, Saudi Arabia 6 Department of Public Health, College of Health Sciences, Saudi Electronic University, Riyadh, Saudi Arabia 7 Department of Diagnostic Radiology, King Abdullah Medical City, Makkah, Saudi Arabia 8 Vascular Laboratory, Hammersmith Hospital, Imperial College NHS Healthcare Trust, London, UK 1 Abstract Background: Ultrasound elastography, a non-invasive imaging modality, holds promise for assessing tissue stiffness, offering potential applications in the evaluation of cardiovascular disease. This study aimed to quantify local stiffness of the abdominal aortic wall using two-dimensional shear wave elastography (2D-SWE) in adults without underlying medical conditions, and to evaluate its reproducibility. Methods and Results:2D-SWE measurements of infra-renal posterior wall of the abdominal aorta (PWoAA) were obtained from 50 subjects. For intra- and inter-observer reproducibility, five 2D-SWE measurements of PWoAA were averaged, and the measurements were performed two times by observer A and once by observer B (n=750). Intraclass correlation coefficient (ICC) and Bland-Altman plot were used to establish bias and limit of agreement (LoA) between PWoAA elasticity measurements. Ultrasound 2D-SWE of PWoAA was 3.87±0.99 kPa. Intra-observer agreement of PWoAA ultrasound 2D-SWE elasticity measurements was moderate with an ICC value of 0.69 (95% CI: 0.56–0.82, P<0.001). Bias in intra-observer measurements was 0.18±0.92 kPa (95% LoA: -1.62–1.99). Similarly, inter-observer agreement was moderate with an ICC value of 0.56 (95% CI: 0.22–0.75, P=0.002). Bias in inter-observer measurements was -0.02±1.09 kPa (95% LoA: -2.16–2.11). There was no significant difference in the 2D-SWE measurements of the aortic walls, both within the same observer (mean difference [MD] 0.17, 95% CI: 0.07–0.44, P=0.16)) and between two different observers (MD=0.02, 95% CI: 0.33–0.28, P=0.86). Conclusion: Our findings demonstrated moderate reproducibility of ultrasound 2D-SWE in assessing abdominal aortic wall elasticity, with no significant differences within or between observers. Further research is warranted to optimize the clinical application of this method for assessing arterial wall stiffness, particularly in patients with cardiovascular disease, including those with abdominal aortic aneurysms.(International Journal of Biomedicine. 2025;15(4):690-694.) Keywords: ultrasound elastography • 2D-SWE • aortic stiffness For citation: Sultan SR, Alsayegh L, Almsaari HB, Khalil M, Alfatni A, Kaifi R, Alkharaiji M, Alzahrani A, Aslam M. The Two-Dimensional Shear Wave Elastography (2D-SWE) in Assessing Abdominal Aortic Wall Stiffness. International Journal of Biomedicine. 2025;15(4):690-694. doi:10.21103/Article15(4)_OA7 Abbreviations AS, aortic stiffness; ICC, intraclass correlation coefficient; LoA, limit of agreement; PWoAA, posterior wall of the abdominal aorta. S. R. Sultan et al. / International Journal of Biomedicine 15(4) (2025) 690-694 Introduction Aortic stiffness (AS) characterizes elastic resistance to deformation. It is intricately influenced by the dynamic interplay between vascular smooth muscle cells and extracellular matrix components, including fibrillin fibers, elastin, and collagen.1 This biomechanical property assumes significance, as elevated AS reflects maladaptive responses to hemodynamic stress and imposes an increased afterload on the heart. It is considered a non-invasive indicator of metabolic disorders and a critical factor in assessing cardiovascular risk.2,3 Several methodologies have been used to assess AS noninvasively.2 Pulse wave velocity (PWV) is a widely utilized approach that calculates the speed of the pressure wave along the aorta. This is achieved by measuring the pulse transit time between the carotid and femoral sites and determining the distance between them.4 In addition, ultrasound-based techniques, including aortic arch pulse wave velocity (aaPWV) and carotid-femoral pulse wave velocity (cfPWV), by assessing pulse wave Doppler, have been reported to provide valuable insights for measuring AS.5,6 Ultrasound two-dimensional shear wave elastography (2D-SWE) enables quantitative measurements of tissue stiffness in real-time.7 It employs acoustic radiation force impulses induced into tissues through focused ultrasonic beams, capturing the real-time propagation of resultant shear waves.8 This enables the display of elasticity as a colored map overlay on a B-mode image, providing a holistic visualization of tissue stiffness.9 Although ultrasound 2D-SWE is promising a diagnostic tool in assessing liver diseases, thyroid nodules, and breast conditions, its potential for evaluating abdominal aortic wall stiffness remains an underexplored. Therefore, in this study, we aimed to quantify the local stiffness of the abdominal aortic wall using 2D-SWE ultrasound in adults without underlying medical conditions, and to evaluate its reproducibility. 691 the visit, and their heights and weights were taken. Then, they were asked to lie in a supine position for approximately 20 minutes. Afterward, brachial blood pressure and heart rate were measured by placing a Microlife monitor cuff on the upper arm, followed by ultrasound imaging of the abdominal aorta for normality assessment. The ultrasound imaging procedures were conducted using a high-resolution ultrasound system, EPIQ Elite (Philips Health Care ultrasound imaging system), with 2D-SWE capability using a 5-1MHz curvilinear transducer for optimal image acquisition. Ultrasound 2D-SWE was assessed in real-time. Ultrasound 2D-SWE of infra-renal PWoAA were obtained by placing the ultrasound transducer along the midline of the abdomen in the longitudinal plane. A sufficient amount of gel was applied while participants lay in a supine position with their arms resting by their sides, and they were instructed to hold their breath at an end-expiratory level to ensure uniform depth of aorta visualization during assessments and the acquisition of high-quality elastography images. Measurements were taken during dia (...truncated)