Structure and anatomy of the aortic root

Understanding the anatomy of the aortic root is particularly relevant in the current era of evolving management strategies including percutaneous and transcatheter therapeutic techniques for valve or device implantations. This review describes the aortic root as a composite structure of several elements, not only the valvar leaflets. The valvar leaflets have a unique shape with deep closure lines buttressed by the nodule of Arantius. The scalloped configuration of the hingelines of the leaflets crosses the ventriculo-arterial junction, leaving interleaflet fibrous triangles between the sinuses that are anatomically aortic but haemodynamically ventricular. The fibrous triangle between the right and the non-coronary leaflets is the guide to the location of the atrioventricular conduction bundle. The coronary orifices are located close to the level of the sinutubular junction. Variations in leaflet structure and their arrangements result in valvar stenosis or regurgitation, or both. Often, diseases of the aortic root involve more than one structural element. The leaflets and their hingelines, aortic sinuses, interleaflets triangles sinutubular junction, and ventriculo-arterial junction and their structures adjoining the junctions should be taken into account when considering the aortic root. Owing to its central location, the aortic root is in close proximity to all the cardiac chambers, the atrial septum, ventricular septum and the atrioventricular conduction bundle.