Differences in aortic cusp coaptation between the reimplantation and the remodeling techniques of aortic valve-sparir surgery: an in vitro porcine model study

Objectives: We sought to evaluate the effects of the reimplantation type versus the remodeling type of aortic valve-sparing technique on the geometry of the same aortic root. Methods: Fifteen fresh isolated porcine hearts with normal aortic valves and a standard aortoventricular junction size of 23 mm were processed. An aortic valve-sparing replacement was performed by reimplanting the native aortic root inside a 28-mm Valsalva graft (Vascutek Ltd, Renfrewshire, UK). Hearts were subsequently implanted with instruments in a test circuit, and the aortic roots were pressurized at a fixed pressure of 100 mm Hg. Diameters of the aortoventricular junction, of the sinuses, and of the sinotubular junction, as well as effective height and coaptation height of aortic valve leaflets, were measured by echography. Transition from the reimplantation to the remodeling configuration was then achieved by longitudinally cutting the skirt of the graft from the annulus to the top of each commissure. The same measurements were then repeated. Results: After transition from the reimplantation to the remodeling configuration, significant increases in the sizes of the aortoventricular junction and of the sinuses were observed. Effective height and coaptation height significantly decreased, and the rounded cross-sectional profile of the aortic valve leaflets flattened. Conclusions: In the same aortic root, transition from the reimplantation to the remodeling configuration of aortic valve-sparing surgery results in a significant increase in aortic root sizes and in a significant reduction of effective height and coaptation height, suggesting a less satisfactory result.