A system includes a therapy control circuit, a therapy output circuit and a physiologic interval sensing circuit configured to receive information about subject physiologic intervals. The therapy circuit is configured to determine a change in therapy that is provided by the therapy output circuit, determine that the change in therapy includes a change to a maximum interval of cardiac electrostimulation provided according to the therapy, detecting a change in a ventricular filling characteristic of the subject in response to the change in maximum interval of cardiac electrostimulation, determine an indication of a physiologic response of the subject to the therapy change using information about the change in the ventricular filling characteristic, and update the subject therapy provided by the therapy output circuit when the determined indication of the physiologic response to the therapy change indicates an increased likelihood of worsening health status of the subject.
