A rotational pump capable of running at a rotational speed (n) having a system for direct or indirect measurement of pressure difference or flow rate across the pump, wherein a control system is designed to calculate an index of pulsatility (PI) of the pressure difference or flow rate, estimating the gradient of PI with respect to the rotational speed (dPI/dn) and regulating the dPI/dn to a pre-defined set-point or regulating the pump in a way that the dPI/dn is minimal.