Geometrical difference between an ascending aneurysm and a root aneurysm in valve-sparing operations

The aortic root geometry of the leaflet size and coaptation in an ascending aortic aneurysm, and in a root aneurysm, may predict the early and late outcomes from valve-sparing surgery.

The aortic root was investigated using intraoperative endoscopy before and after valve-sparing root reconstruction. The definition of 'root aneurysm' was marked sinus dilatation proximal to the sinotubular junction. 'Ascending aneurysm' was defined as dominant dilatation distal from the sinotubular junction. Fifteen cases were examined and classified into two groups; Group A with an ascending aneurysm (four patients), and Group R with a root aneurysm (eleven patients).

Cusp prolapse was seen in 10 (90.9%) patients of Group R, and in only one (25%) patient of Group A. The length of the free margin of all cusps in Group R was significantly longer than those in Group A. In Group R, the lengths of the free margin of an individual cusp were significantly different, indicating asymmetric cusps. In Group A, the length of the free margin were similar, indicating symmetric cusps. There was no significant difference in the degree of immediate postoperative aortic insufficiency, between the two groups. At the most recent follow-up, progressive aortic insufficiency was present in two patients of Group R.

A root aneurysm had asymmetric, elongated and prolapsed aortic cusps, while an ascending aneurysm had symmetric cusps without prolapse. The mechanism of aortic insufficiency in a root aneurysm was more complex, suggesting a difficulty in achieving long-term valve competence. Such geometrical difference should be considered in the indication for the surgical technique of valve-sparing operations.