A device and method for controlling commissural tip deflection of a prosthetic valve, thereby both preventing failure due to repeated movement and/or uneven loading of the commissural points and also improving coaptation of the valve leaflets, including connecting reinforcing material between the commissural points so a spring-like span is created across the points. The spanning material may be in the form of a ring that is lashed, sewn or otherwise connected to the commissural points. The reinforcing material may form curved segments between the commissural points that extend outwardly to form sinuses behind the leaflets of the prosthetic valve. The reinforcing material may also extend in an upstream direction to avoid interfering with blood flowing out of the prosthetic valve.