Abstract: An implantable measuring device includes a catheter-like main body that can be positioned in a body cavity. The main body has a pressure-sensitive sensor thereon and a signal line is coupled to the sensor. The signal line transmits measuring signals generated by the sensor and corresponding to the detected pressure to a signal evaluation unit. A cleaning element is coupled to the sensor. The cleaning element is in the form of a piezoelectric actuator that can be set to vibrate by electrical excitation. The vibrations of the cleaning unit are transferable to the sensor for the removal of deposits.