Effects of aging and body size on proximal and ascending aorta and aortic arch: inner edge-to-inner edge reference values in a large adult population by two-dimensional transthoracic echocardiography.

BACKGROUND

Aortic size is known to vary significantly by age and body size and to be an important predictor of cardiovascular diseases. The aim of this study was to determine reference values for proximal thoracic aorta diameters, using the inner edge technique and two-dimensional transthoracic echocardiography.

METHODS

Diameters of the aortic annulus, sinuses of Valsalva, sinotubular junction, arch, and ascending aorta and the angle of insertion of the aorta were measured in 500 subjects (231 women; mean age, 48 ± 18 years) with normal echocardiographic findings, retrospectively enrolled. The relations of age and body size with aortic measurements were investigated using bivariate and multiple linear regressions.

RESULTS

Measurements were highly feasible (83% for the aortic arch, 100% for the other segments). All aortic diameters significantly related to age, weight and body surface area, while height was correlated only with annular diameter. In predictive models adjusted for gender, older age was associated with increased aortic diameters (R(2) values ranged from 0.36 for the sinotubular junction to 0.52 for the sinuses of Valsalva). Adjustments for height and weight led to significant improvements (R(2) values ranged from 0.43 for the sinotubular junction to 0.58 for the sinuses of Valsalva). Similar correlations were observed for men and women. Angle was found to be dependent only on age and gender. Reproducibility analysis showed good to excellent accordance between repeated measurements.

CONCLUSIONS

The results of this study show the effect of aging on the proximal thoracic aorta and emphasize the importance of accounting for gender and body size when assessing aortic size. The obtained reference ranges will help standardize the assessment of aortic dimensions by applying inner edge convention and facilitate comparisons with other imaging techniques.