A catheter pump includes a catheter channel (36) communicating with a distal end portion of the catheter for alternatingly leading fluid in proximal and distal directions. At least one outlet passage (26) is distally spaced from the inlet passage or passages (25). The catheter pump further includes a displacement structure (16) communicating with the proximal end portion of the catheter for alternatingly applying suction and pressure for driving the fluid displacement. At least in operating condition, the inlet passage or passages (25) is resp. are continuously open. A catheter and fittings (27, 28) for such a catheter pump and method of using a catheter pump are also described.
