A heart pump is provided that comprises an elongate catheter body, an impeller disposed at the distal end of the elongate catheter body, and one or more bearings positioned between the catheter body and the impeller. A fluid supply line for delivering infusant into the catheter is provided. A fluid return line for transporting infusant out of the catheter is also provided. A pump assembly for regulating the infusant flow along the fluid supply line and fluid return line is provided as part of an infusion system.