Impact of angle between interventricular septum and ascending aorta on ellipsoid-shaped aortic annuls evaluated by three-dimensional transthoracic echocardiography

Abstract

Background: Real-time three-dimensional (3D) transesophageal and transthoracic echocardiography has developed and provided detailed 3-dimensional aortic root geometry, and then the presence of ellipsoid-shaped aortic annuls (ESAA) in some patients were reported. However, the characteristics of patients with ESAA were unknown. Method: To evaluate the relation between these parameters and ESAA, 55 patients without cardiovascular diseases were performed 3D transthoracic echocardiography (3DTTE). Using 3DTTE, minimum and maximum diameters of AA and AA area were measured, and eccentricity index (EI: 1 – minimum diameter/maximum diameter) was calculated to evaluate the shape of the aortic annuli. In addition, the angle between interventricular septum and ascending aorta (IVS-Ao angle), left ventricular volume, left ventricular mass, age, and blood pressure were also measured. Results: Defining ESAA as EI of AA >0.1, ESAA was shown in 25 (45%) of all patients. IVS-Ao angles were significantly smaller in ESAA group than that in non-ESAA group (118±14 vs 135±14, p<0.01) and were correlated to EI of AA (Figure). In addition, age and IVS-Ao angle had significantly correlation with EI of AA. In contrast, In all of 11 patients ≤55 years of age, EI of AA were less than 0.1, that is, none of patients ≤55 years of age had ESAA. ![Figure][1] Conclusion: Our findings suggest that 3DTTE revealed that the shape of the aortic annulus was almost circular in younger people (≤55 years of age), but the ellipsoid-shaped aortic annuls in older people (>55 years of age) was associated with acute angle between interventricular septum and ascending aorta. [1]: pending:yes