P2788First argentine national registry of echocardiograpphic aortic dimensions: body surface area, age and ethnicity are determinants of aortic dimensions

Abstract

Abstract Background Transthoracic echocardiography (TTE) remains the screening tool of choice for thoracic aorta (TA) dilatation. Differences in TA diameters (TAD) according to gender (G), age (A) and body surface area (BSA) have been previously reported. However, these reports are limited by a small sample size, different measurement sites or heterogeneous cohorts. There is scarce data on the influence of ethnicitiy on TAD. Moreover, surgery indication for TA aneurysms is still based mainly on absolute TAD with no reference to G, A or BSA. Purpose We designed a prospective nationwide multicenter registry to determine the normal range of TAD at all TA segments in healthy adults of both G and their correlations with A, ethnicity and BSA. Methods Healthy adult individuals without cardiovascular risk factors, TA aneurysm, aortic valve disease, cardiac surgery or genetic aortopathies were recruited from 53 centers in Argentina. TTEs were acquired and measured following standard protocols based on EACVI/ASE Guidelines. TAD were measured at six levels: annulus, sinuses of Valsalva, sinotubular junction, tubular ascending aorta, aortic arch and proximal descending aorta. Annulus was measured at mid-systole (inner to inner edge method) and all other at end-diastole (leading to leading edge). Multiple linear regression models were conducted to obtain coefficients of determination (R2) and 95% prediction intervals. We defined upper normal limits (95th percentile) for 4 age categories, both G and analyzed differences according to ethnicity. Results The MATEAR registry included 905 healthy adult patients (mean age: 38.3±13 years, 508 women, BSA: 1.8±0.2 m2). 529 (58.4%) were caucasian and 332 (36.6%) native-american, representative of the ethnic composition of Argentine population. Pooled data showed a positive correlation between all TAD and A or BSA (p<0.001), similar in both G. Women had smaller absolute TAD due to their lower BSA. Nomograms were obtained for 4 age categories to predict TAD from BSA with no need of G distinction. Native americans showed significatly lower absolute and indexed TAD than caucasian (p<0.01) from annulus to isthmus. TAD differences according to ethnicity Conclusions While age and BSA were significant determinants of aortic dimensions at six levels, we have also detected differences in TAD according to ethnicity, suggesting normative values should also be defined for each ethnic group. We propose nomograms of indexed TAD for different age and ethnic groups without G distinction.