Effect of the sinus geometry on the dynamics of bioprosthetic heart valves

The authors examined the effect of the geometry of the sinuses of Valsalva on the dynamics of pericardial and porcine bioprosthetic valves. Various sinus geometries (no sinus, finite sinus, infinite sinus) were created using a Dacron graft. The experiments were done in a left heart simulator, filled with saline, at various aortic pressures and cardiac outputs at 71 BPM. For both, the pericardial and the porcine valves, the duration of rapid opening or rapid closing was not affected by the sinus geometry. For both the valves, the orifice area was slightly larger and the leaflet belly started to move inward earlier in the presence of the sinus. The sinus geometry had no significant effect on the regurgitant fraction. In conclusion, the presence of the sinus appears to have only marginal influence of the dynamics of the bioprosthetic valves. It is possible that the hemodynamic contribution of the sinus geometry is more significant in the natural valve and/or that the sinuses are more important for the stress distribution between the leaflet-sinus assembly