Seeing is better than believing

Aortic valve repair has become an increasingly attractive alternative to replacement both for root aneurysm and aortic regurgitation. The goal of such repair procedures is the creation of a normal form of the aortic valve, with normal function as the consequence.

Quite apparently, a normal aortic valve is characterized by all free cusp margins being at the same level, and this feature has traditionally been used to guide aortic valve repair. This, however, is more difficult to assess intraoperatively than it sounds. Under physiologic conditions the aortic root is pressurized, pushing the cusps caudally and the commissures in a centrifugal direction [1]. The surgeon sees the aortic valve when the aorta is cross-clamped and the root is not pressurized, leading to distortion of the root and thus also the valve. This distortion can be (partially) neutralized by connecting the valve to a vascular graft in valve-preserving root replacement. This graft is more rigid than the native aorta; nonetheless, some degree of distortion is unavoidable, even if it is only caused by the crimping of the graft. The experience of a larger group of surgeons [2] shows that suboptimal valve configuration is a relatively frequent consequence, leading to (avoidable) regurgitation and possibly the need for earlier reoperation.

The approach of inspecting the valve with the root under pressure [3] is a logical step to improve surgical results. It allows visual inspection of the valve under pressurized and thus more physiologic conditions. It can thus be expected to contribute to improve the results of valve-preserving root replacement. This concept, however, should only be a first step. In addition to normalizing root dimensions, adequate cusp size and configuration are as important as equalization of the free margins. This includes quantification of the amount of cusp tissue, e.g. as geometric height [4, 5] and—importantly—the level of the free margins above the annular plane, i.e. effective height [5, 6]. Both geometric parameters have been found to be important components of successful cusp repair and valve-preserving root replacement [7, 8]. The visual information provided by the current approach [3] does not provide such information. For a complete assessment of the aortic valve, further information will be necessary. Geometric height can be measured directly prior to the repair; cusp configuration could potentially be quantified using an added 3-dimensional echocardiographic examination.

The current approach [3] is expected to improve the quality of aortic repair procedures. Further refinement will be needed to render such procedures even more reproducible.

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