Haemodynamics :  The type of valves chosen should have excellent haemodynamics. In studies at rest and on exercise the valve should produce only acceptable diastolic gradients in the mitral position and systolic gradient in the aortic position. This will depend mainly on the effective orifice area (EOA) of the particular valve.

Prosthetic Valve haemodynamics

A high profile valve like Starr-Edward may cause problems if not properly used. In mitral stenosis with small left ventricle such a valve is better avoided. Similarly when the ascending aorta is narrow it has to be enlarged to accommodate a Stm-Edward valve.