This link states that Kvs is the metric equivalent of Cv. Specifically, the link states that Kvs is the flow m^3/hr per 1 bar (100 kPa) pressure difference. Flow can be calcualated as,
m^3/hr = kvs * sqrt(dP)
where dP is the pressure difference in bar.
Are there any units for your Kvs values?
I have also seen the equation written as
m^3/hr = kvs * sqrt(dP * rhoref/rho)
to account for fluids at different temperatures where rhoref is the cold water reference density (1000 kg/m3) and rho is the actual water density.