Figure 1. A: The lowest points of leaflet attachments in the nadirs of sinuses of Valsalva (R, L, N) were marked on the segmented aortic root and were used to define the annular plane. The highest points of the three commissures were also marked and used to define the sinutubular plane. Next spline tool was used to trace leaflet attachment lines, geometric heights, annular and sinutubular perimeters and leaflet coaptation areas. B: Example of geometric height (GH) and coaptation area (CA) measurement on CTA.