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Aortic root surgery is among the most complex procedures in an already
technically demanding surgical specialty of cardiac surgery. A thorough
understanding of the anatomy, and subsequent appreciation of abnormal
findings, with avoidance of potential pitfalls is critical. Knowledge
and acknowledgement of these subtle details, however, comes with
experience. Thus, we are sharing our experience and highlight our
approach to restore a more physiologic anatomy, which allows for
execution of a standard technique without the risk of failure related to
this particular anatomic entity.
The underlying principle described here, is that we sewed the horizontal
plane of the graft-reinforced pulmonary autograft, to a newly created
horizontal and even plane of the aortic annulus. With this, we avoided
distortion of the prosthetic graft with subsequent distortion of the
neo-aortic valve. Distortion of the neo-aortic valve would lead to
aortic regurgitation, due to prolapse or cusp restriction, and
subsequent potential failure of the procedure despite a correct surgical
execution. The potential culprit for failure here, is not a lack of
surgeon skills, but an unusual anatomical detail, which potentially
wasn’t recognized or taken into consideration.
Moreover, when regarding the quality of the tissues in the left coronary
sinus, it becomes evident that the tissues are quite thin and would not
be able to adequately hold the sutures of the pulmonary autograft. It
also lacks the ability to provide any annular support and may therefore
also compromise durability of the repair. Thus, the annular elevation
and reinforcement alleviates the weaknesses of the annulus and sinus
wall. We most commonly observe these changes in the non-coronary sinus.
But this case highlights the notion, that these changes can affect any
of the aortic root sinuses.
The principles we presented here, do not only apply to the pulmonary
autograft but are universally applicable to any aortic annulus or root
technique. The only difference is that some techniques, such as
prosthetic valve replacements for instance, are more forgiving. Despite
that, even earlier generations of bioprosthetic valves required
modifications from a horizontal plane of the sewing ring to a more
scalloped formed ring. Hence, the scalloped sewing ring is anchored to a
scalloped aortic annulus, the natural from of the aortic cusp insertion
line. This allows for a more physiologic placement of the prosthetic
valve and decreases the possibility for errors. Hence, the form of the
bioprosthetic valve sewing ring was adjusted to better fit the natural
anatomy of the aortic annulus. In this case however, we adjusted the
aortic annulus to the root replacement substrate. We chose a graft
reinforced autograft, which had an even plane to sew to. Of course, we
could have also performed a Bentall procedure, but in young patients we
prefer the pulmonary autograft due to the improved long-term survival
and better quality of life 8.
Recognizing and understanding these subtle details, however, is
important to avoid potential pitfalls when dealing with the aortic root
and annulus.