Background: The aortic root diameter (AoD) has been shown to be a marker of cardiovascular risk and heart failure (HF). Data regarding the normal reference ranges in Asians and their correlates with diastolic dysfunction using contemporary guidelines remain largely unexplored.
Methods: Among 5343 consecutive population-based asymptomatic Asians with echocardiography evaluations for aortic root diameter (without/with indexing, presented as AoD/AoDi) were related to cardiac structure/function and N-terminal pro-brain B-type natriuretic peptide (Nt-ProBNP), with 245 participants compared with multidetector computed tomography (MDCT)-based aortic root geometry.
Results: Advanced age, hypertension, higher diastolic blood pressure, and lower body fat all contributed to greater AoD/AoDi. The highest correlation between echo-based aortic diameter and the MDCT-derived measures was found at the level of the aortic sinuses of Valsalva (r = 0.80, p < 0.001). Age- and sex-stratified normative ranges of AoD/AoDi were provided in 3646 healthy participants. Multivariate linear regressions showed that AoDi was associated with a higher NT-proBNP, more unfavorable left ventricular (LV) remodeling, worsened LV systolic annular velocity (TDI-s'), a higher probability of presenting with LV hypertrophy, and abnormal LV diastolic indices except tricuspid regurgitation velocity by contemporary diastolic dysfunction (DD) criteria (all p < 0.05). AoDi superimposed on key clinical variables significantly expanded C-statistic from 0.71 to 0.84 (p for ∆AUROC: < 0.001). These associations were broadly weaker for AoD.
Conclusion: In our large asymptomatic Asian population, echocardiography-defined aortic root dilation was associated with aging and hypertension and were correlated modestly with computed tomography measures. A larger indexed aortic diameter appeared to be a useful indicator in identifying baseline abnormal diastolic dysfunction.
Keywords: N-terminal pro-brain B-type natriuretic peptide (Nt-ProBNP); aortic root diameter; diastolic indices; heart failure; multidetector computed tomography (MDCT).