Aortic Root Dynamics in Sleeve Aortic Sparing Procedure: Echocardiographic and Computational Studies

In Sleeve procedure, the leaflets-sinus unit is maintained. We hypothesized that this feature partially preserves aortic root (AR) dynamics and leaflets kinematics and limits tensions in the leaflets. We tested our hypothesis based on in vivo and computational assessment of leaflets and AR dynamics. AR and aortic leaflet kinematics was assessed by transthoracic echocardiography in 10 patients treated with the Sleeve procedure and in 10 healthy patients. Numerical calculations with the Finite Element Method were performed to support the analysis of the clinical results and provide a better understanding of the behavior of the AR treated via the Sleeve procedure. Echocardiographic evidence showed that AR expansion in the Sleeve group was partially preserved as compared to the Control group (2.9 ± 2.5% vs 7.7 ± 6.3%, P = 0.038) and of the sinotubular junction (2.9 ± 1.5% vs 7.3 ± 3.8%, P = 0.003), and significantly preserved at the Valsalva sinuses level (6.7 ± 2.6% vs 9.5 ± 4.3%) with not statistically significant differences (P = 0.11). In none of the cardiac phases, differences in aortic valve leaflets kinematics were measured between the 2 groups; computational results were rather consistent with this evidence. Computational results well matched echocardiographic evidences, allowing for their mechanistic interpretation. Near-normal opening and closing characteristics can be accomplished by a technique that preserves the shape and the dynamics of the Valsalva sinuses. Whether the substantial preservation of the AR distensibility and leaflets kinematics observed in this study will favorably affect long-term valve durability it remains to be ascertained.