Legends to Figures
Figure 1. As is correctly stated by the authors of the response
to our letter published in JCTVS Open,4 a “cusp” is
the feature “formed by the intersection of 2 arcs or curved lines”. As
can be seen, such “cusps” are to be found in the atrioventricular
valves, as shown for the tricuspid valve in panel A, as well as in the
arterial valves (panel B). In both valves, however, the feature is
usually described as a “commissure”, rather than a “cusp”.
Figure 2. The images show selected cuts made from a computed
tomographic three-dimensional reconstruction of the normal trileaflet
and trisinuate aortic root. Panels A and B show short (A) and long axis
(B) views positioned over a two-dimensional plane constructed at the
level of the virtual basal ring. The superior extent of the myocardial
crescents incorporated into the coronary sinuses is outlined with an
orange line. It is the junction between the sinusal walls and the
myocardial crescents that dictates the anatomical ventriculo-arterial
junction, which is not present in the non-coronary sinus (N). The
semilunar hinge lines of the valvar leaflets, shown by the red lines,
extend from their nadir at the plane of the virtual basal ring, shown by
the green line, to their zenith at the sinutubular junction, which is
marked by the blue line. These hinge lines dictate the hemodynamic
ventriculo-arterial junction. The interleaflet triangles, marked by the
purple triangles, are positioned between these hinge lines. The
interleaflet triangle between the coronary aortic sinuses has muscle at
its base. This forms another part of the anatomical ventriculo-arterial
junction. The interleaflet triangle between the right (R) and
non-coronary sinuses has the membranous septum (colored yellow) at its
base, with the septum positioned so as to be transected by the plane of
the virtual basal ring. Panels C and D then show further virtual
dissections, with panel C showing a cut between the right and
non-coronary sinuses, and Panel D showing a cut through the two coronary
aortic sinuses. Further abbreviations: L, left coronary sinus; LCA, main
stem of the left coronary artery; RCA, right coronary artery.
Video 1 . The normal aortic root as shown in Figure 2A and B is
shown, initially viewing the root in short axis, and then rotating 360
degrees around its long axis. The non-coronary sinus is seen first,
followed by the right, and then the left coronary aortic sinuses.