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).