Circumferential deformation of the thoracic aorta in hypertensive patients by three-dimensional speckle tracking echocardiography

Background: Aortic stiffness may be associated with an increased incidence of cardiovascular events and has been reported to be related to arterial wall motion velocities as measured by tissue Doppler imaging (TDI). The aim of this study was to investigate the potential clinical apllication of three-dimensional speckle tracking echocardiography (3DSTE) for the assessment of aortic function parameters in healthy and hypertensive adults. Methods: We examined 95 hypertensive (mean age, 67 ± 14 years; 53% male) and 95 healthy adults (mean age 69 ± 12 years; 51% male). Ascending aorta M-mode, TDI and STE parameters were measured. Aortic distensibility (D) and aortic stiffness index (SI) were calculated using accepted formulae. Global peak circumferential ascending thoracic aorta strain by 3DSTE (3D-AoS) was determined (GE EchoPAC) as an average of multiple segments of arterial wall deformation. The corrected 3D-AoS was calculated as the global 3D-AoS/pulse pressure. Comprehensive echocardiography was performed for the assessment of the LV systolic/diastolic function. Results: Intraobserver variation of 3D-AoS ranged from 3% to 5% and interobserver variation ranged from 4% to 7%. Both D (p<0.05) and 3D-AoS (p<0.001) were significantly lower in hypertensive compared to control subjects. Reduced D and increased SI were consistent with evidence of increased aortic stiffness in both male and female hypertensive patients. SI increased and D decreased with increasing age or systolic blood pressure. Multivariate analysis showed 3D-AoS to be independently related to pulse pressure (p<0.01), LV mass index (p=0.003), and diastolic function (p=0.002). Conclusions: Aortic 3DSTE parameters have higher reproducibility compared to TDI and 2D indices, differentiate hypertensive from healthy adults, and reflect aortic compliance changes related to age and sex and LV diastolic function.