Comparisons of Two-dimensional Echocardiographic Aortic Dimensions Between Chinese, Japanese, and Europeans

Purpose: We aimed to investigate the impacts of age, gender, and race on aortic dimensions in healthy adults. Methods: We analyzed data from 3 large population-based sample studies, including Chinese Echocardiographic Measurements in Normal Chinese Adults, Japanese the Normal Values for Echocardiographic Measurements Project, and European Normal Reference Ranges for Echocardiography, to compare the two-dimensional echocardiography-derived aortic diameters at different levels and to explore the effects of age, gender, and race on aortic measurements. We also compared the values corrected by body surface area (BSA) or height. Results: The results are as follows: (1) Aortic diameters showed positive correlations with age ( r =0.12-0.42, P <0.05), and there were significant inter-age group differences before and after indexing to BSA ( P <0.05); (2) Men had greater measurements of aortic diameters than women, with the differences being the same when indexed to height. However, indexing to BSA reversed the differences; (3) The aortic diameters at annulus (Ao-a) and sinus (Ao-s) levels were very close with minor differences between the Chinese and Japanese regardless of whether BSA was used for correction; and (4) The aortic measurements at Ao-s and proximal ascending aorta (Ao-asc) levels in the Chinese were significantly lower than in the Europeans for both genders, with the differences remaining the same even after indexing to BSA or height ( P <0.05). Conclusion: Aortic dimensions vary with age and gender, and there are significant differences between races or ethnicities even when stratified by gender and age. The indexation by BSA or height cannot eliminate these differences. Therefore, age-specific, gender-specific, race-specific, and nationality-specific reference values may be more appropriate at present for clinical practice to avoid misdiagnosis and misclassification of aortic dilation.