A catheter pump is disclosed herein. The catheter pump can include an elongate catheter body and an impeller assembly coupled to a distal portion of the elongate catheter body. The impeller assembly can comprise an impeller configured to rotate during operation of the catheter pump. A tube can extend through at least portions of the elongate catheter body and the impeller assembly. The tube can extend distal the impeller and can be configured to remain in the portions of the elongate catheter body and the impeller assembly during operation of the catheter pump.