Results
Baseline patient and aortic valve data are presented in Table 1, 2 and 3, and are graphically summarized in Figures 2 and 3, where measurements are normalized to either annular mean diameter to allow comparison to data published by Swanson and Clark5 or to mean leaflet geometric height to allow comparison to data published by De Kerchove et al6.
Mean age of patients was 53 ± 11 years, with no difference between men and women (Table 1), 50% of patients (n = 35) were female. Men were higher and heavier, with larger aortic valves (larger annular diameter, sinutubular junction diameter and all leaflet dimensions), however the geometry of aortic root and leaflets was similar (all angles as well as normalized dimensions were similar) (Table 2). The right coronary leaflet had the longest mean free margin length (35.2 ± 4.1 mm) and intercommissural distance (25.1 ± 3.0 mm), whereas the noncoronary leaflet had the longest mean geometric height (16.5 ± 2.0 mm) and leaflet attachment length (51.7 ± 6.6 mm). Right-noncoronary commissure was the highest of the three (20.6 ± 3.0 mm). Mean valve height calculated as the distance between annular and sinutubular plane centroids was 19.2 ± 2.2 mm and the central coaptation point of the three leaflets was located at 46% of the distance between annular and sinutubular plane, starting from the annular plane. Mean effective leaflet height was 8.5 ± 1.4 mm, and there were no significant differences between the three leaflets. Mean angle between annular plane and sinutubular plane was 7.8 ± 3.9 degrees (Table 3). Noncoronary leaflet occupied the smallest angle relative to the sinutubular plane (116 ± 6 degrees).
Asymmetry of the three cups in individual patients is summarized in Table 4. All absolute and relative differences between the three leaflets were significantly larger than zero. Absolute and relative differences for free margin length were 3.2 ± 1.4 mm and 9.3 ± 3.8%, respectively. The largest relative difference was noted in coaptation area (36.5 ± 16.5%) and the smallest in leaflet effective height (6.1 ± 4.8%). Using the cut-off values for absolute differences in free margin length, geometric height, intercommissural distance, and leaflet attachment length defined by De Kerchove et al6 aortic valves were classified into symmetric and asymmetric (Table 5). Using each of these criteria separately, on average 42% of the valves were classified as asymmetric. However, observing all four criteria at once, only 10 (14%) valves were symmetric and 60 (86%) had at least one criterion for asymmetry (28 (40%) had one criterion, 14 (20%) had two criteria, 11 (16%) had three criteria, and 7 (10%) had all four criteria for asymmetry).