Comparison of aortic valve repair techniques with single and double ring annuloplasties.

Abstract

For patients with isolated aortic regurgitation, a double sub- and supravalvular annuloplasty has been shown to reduce recurrent aortic regurgitation after aortic valve repair compared with a single subvalvular annuloplasty. The objective of this study was to compare the geometrical and dynamic properties of a single- and double ring annuloplasty in an in vitro model. Eighteen aortic roots from 80 kg pigs were randomized into a control, single ring, and double ring group. Experiments were conducted in a pulsatile in vitro model. Hydrodynamics, radial force measurements at annular and sinotubular level, and 2D echographic imaging were obtained. Both the single- and double ring annuloplasty downsized the aortic annulus and sinotubular junction significantly, and increased the coaptation height. The double ring annuloplasty showed an additional significant increase in coaptation height compared with the single ring (8.5 (0.9) mm to 9.8 (0.8) mm, p < 0.01). The single ring annuloplasty reduced radial forces at both levels, whereas the double ring annuloplasty showed the greatest force reduction of the sinotubular junction. By treating the whole functional aortic annulus, encompassing both the aortic annulus and the sinotubular junction, a greater force reduction is observed. A subvalvular annuloplasty alone is efficient in reducing aortic annulus diameter and increasing coaptation height, however, by treating the sinotubular junction as well, an additional effect is observed on coaptation height, creating a more efficient stabilization. Reduction of annular force-distensibility ratio with the double ring annuloplasty compared with the native controls indicate a sustained stabilizing effect.