Comparing hydrodynamic performance in full-root and graft-inclusion Ross technique: An ex vivo study

The Ross procedure is an attractive method for treating young patients with aortic valve disease, but the optimal surgical technique is still under discussion. This study aimed to evaluate the full-root and graft-inclusion Ross techniques in terms of their hydrodynamic performance ex vivo in a simulated circulation model.

A total of 20 porcine autografts were created using either the full-root (n = 10) or graft-inclusion (n = 10) Ross technique. Hydrodynamic performance, including valvular opening morphology, transvalvular gradients, orifice area, and regurgitation volumes, were assessed under different resting and exercise conditions in an ex vivo mock-up circulation model.

Full-root porcine autografts exhibited significantly lower transvalvular pressure gradients and greater orifice areas compared with graft-inclusion autografts (mean pressure gradient: full root 3.6 vs graft inclusion 5.0 mm Hg, P = .007; effective orifice area full root 2.4 vs graft inclusion 2.0 cm², P = .007). Valvular leakage was comparable between the 2 techniques, but graft inclusion showed a significantly lower valvular closing volume compared with the full-root Ross technique (full root: 7.9 vs graft inclusion: 4.8 mL, P = .002). The differences described were significant under all resting and exercise conditions examined.

The full-root technique appears to be advantageous from a hydrodynamic perspective. It revealed lower gradients and greater orifice areas, and the surgical procedure is less complex to perform. However, larger closure volumes may be the reason for dilatation of the neo-aortic root. Therefore, further research on the prevention of neo-aortic root dilatation, focusing on the examination of the closing volume, is needed.