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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.