An implantable medical device includes a multi-axial acceleration sensor and an evaluation unit connected thereto. The evaluation unit is configured to (1) split the accelerometer output signal into at least two signal components, one of which is associated with a right-ventricular contraction and another of which is associated with a left-ventricular contraction (2) detect events in the signal components, and/or determine signal features therein and (3) determine at least one characteristic value K by evaluating the signal components, and/or the events and/or signal features therein.
