A tissue-removing catheter for removing tissue from a body lumen during a cutting operation includes an elongate catheter body configured for insertion into the body lumen and a tissue-removing element. A motor is operably connected to the tissue-removing element for rotating the tissue-removing element. A sensor is configured to detect a parameter of the catheter body during the cutting operation. A motor control circuit is in electrical communication with the sensor and the motor. During an operational control function, the motor control circuit is configured to receive a signal from the sensor based at least in part on the detected parameter, determine whether the received signal is indicative of inefficient movement of the tissue-removing element, and adjust a rotational speed of the tissue-removing element to increase efficiency of the tissue-removing element if the received signal is indicative of inefficient movement of the tissue-removing element.