Improved strategies in aortic valve–preserving operations appreciate the dynamic, three-dimensional complexity of the aortic root and its valve. This depends not only on detailed four-dimensional imaging of the planar dimensions of the aortic root but also on quantitative assessment of the valvar leaflets and their competency. The zones of apposition and resulting hemodynamic ventriculoarterial junction formed in diastole determine valvar competency. Current understanding and assessment of this junction is limited, often relying on intraoperative direct surgical inspection. However, this direct inspection itself is limited by evaluation in a nonhemodynamic state with limited field of view. In this review, we discuss the anatomy of the aortic root, including its hemodynamic junction. We review current echocardiographic approaches toward interrogating the incompetent aortic valve for presurgical planning. Furthermore, we introduce and standardize a complementary approach to assessing this hemodynamic ventriculoarterial junction by three-dimensional echocardiography to further personalize presurgical planning for aortic valve surgery.

Three-dimensional computed reconstruction of the aortic root in diastole viewed in its short axis (A) and longitudinally (B) demonstrates the zones of apposition between the 3 leaflets (shown in white). The commissures (stars) form the lateral aspect of each zone of apposition, with the zone of apposition formed by apposition of the lunules between each adjacent leaflet and centrally by the nodule of Arantius of all 3 leaflets. The belly of each leaflet (colored red) then forms the interface of the hemodynamic ventriculoarterial junction. The shape of this interface is composed of 3 lateral horns spanning from the plane of the virtual basal ring (colored green) to the commissures at the plane of the sinotubular junction (colored blue). In addition, there is a shorter, central horn positioned under the coapting nodules of Arantius (B). (C) The discussed anatomy of the aortic valve leaflet is depicted in the heart specimen. (D, E) Three-dimensional TEE image of the aortic root in long axis in diastole (D) and systole (E), respectively. These images demonstrate the adjacent lunules of the adjacent leaflets, which will appose during diastole, forming part of the zone of apposition. An analogous view of a normal heart specimen is depicted in panel F. LCA, Left coronary artery; RCA, right coronary artery.