Ascending Aorta Elastography After Kawasaki Disease Compared to Systemic Hypertension

Kawasaki disease (KD) is a systemic vasculitis, classically affecting large- and medium-size arteries. The coronary arteries draw most of the clinical attention, whereas few studies have taken interest in the ascending aorta. Using a proprietary imaging-based mechanical biomarker (ImBioMark), we sought to determine aortic stiffness in KD compared to systemic hypertension (HTN) and healthy children. We evaluated parasternal long-axis views focused on the ascending aorta in 20 controls, 12 KD, and 8 HTN as a comparative clinical model of vascular stiffness. We calculated systolic and diastolic aortic wall strain with ImBioMark. Strain was tested for normality against height, systolic, and diastolic blood pressure in normal subjects. Strain from KD and HTN was normalized (Z score) accordingly. Z score comparisons were performed using nonparametric statistics. Age was similar between KD and HTN (9.1 ± 5.3 and 9.9 ± 5.3 years old; p = NS). Systolic and diastolic strain values were normally distributed against height, systolic blood pressure, and diastolic blood pressure in healthy subjects. HTN subjects had abnormal systolic and diastolic strain values (p < 0.0001). Whereas KD subjects had normal diastolic strain, systolic strain was significantly lower (p < 0.001), and systolic strain was intermediate between controls and HTN. There were no significant differences in aortic strain among KD, however, according to the presence of coronary artery aneurysms. Despite normal blood pressure, the ascending aorta in KD exhibits reduced strain during systole. This may reflect in situ rigidity of the aorta. The normal diastolic strain in KD may, in contrast, reflect normal peripheral vascular resistance.