A method for controlling fluid flow in a rotational atherectomy device. A
source of fluid is provided through a pump to the rotational atherectomy
device, wherein the pump maintains the fluid flow at a minimal rate
during a time period when a drive shaft of the device is not rotating. A
first control is activated to increase a rate of the fluid flow and
second control is activated to initiate a rotation of the drive shaft
during another time period when the fluid flow is at the increased rate.