Various techniques are provided for assessing the reliability of
left atrial pressure (LAP) estimates made by an implantable
medical device based on impedance values or related electrical values. In one example, various cardioelectric and cardiomechanical parameters are used to corroborate LAP
estimation in circumstances where the LAP estimates deviate from an acceptable, satisfactory or otherwise healthy range. The cardioelectric parameters include, e.g.: ST elevation;
heart rate (HR);
heart rate variability (HRV); T-wave alternans (TWA); QRS waveform parameters; P-wave duration; evoked response (ER) parameters; and intrinsic PV / AV / VV conduction delays. The cardiomechanical parameters include, e.g.:
heart rate turbulence (HRT); cardiogenic impedance signals;
heart sounds; and non-LAP
blood pressure measurements, such as
aortic pressure measurements. The device compares the cardioelectric and cardiomechanical parameters against corresponding
baseline values to determine whether variations in the parameters corroborate the LAP estimates. If not, the LAP estimates are selectively cancelled or suspended, or the overall procedure is re-calibrated.