Method of selecting an operating mode for an implantable medical device
AssigneeMedtronic, Inc.
InventorsWeimin Sun, Eric J. Panken, William J. Combs
Life of this patent
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Abstract
This is a method and apparatus for the automated discrimination of cardiac events of interest, including P-waves, R-waves, T-waves and specific arrhythmic sequences, in EGM signals for data storage in an implantable monitor or to control operations of an implantable cardiac stimulator through the use of Hidden Markov Modeling techniques and a reduced set of observations.
Claims4
In a medical device having multiple operating modes, a method of ensuring that atrial sense events result from intrinsic P-waves originating in the atria and are not far field R-waves for determining the operating mode of the medical device comprising the steps of:
- sensing the atrial electrocardiogram from at least one electrode positioned in sensing relation to the patient's atria;
- detecting an atrial sense event comprising one of the P-wave or far field R-wave in the atrial electrogram;
- sensing the ventricular electrogram from at least one electrode positioned in sensing relation to the patient's ventricle;
- detecting a ventricular sense event comprising the R-wave in the ventricular electrogram;
- determining the end of the cardiac cycle from successive ventricular sense events;
- during each cardiac cycle, discriminating intrinsic P-waves from far field R-waves in the atrial electrogram using Hidden Markov Modeling (HMM), wherein the P-wave and far-field R-wave can each be characterized as a state separated by state transitions in a hidden state sequence and wherein there are discrete probabilities that the states will transition from one to the other in a predetermined order;
- and
- based on the HMM discrimination of the atrial sense events as intrinsic P-waves or far field R-waves, determining an operating mode of the implantable medical device.
In a medical device having multiple operating modes, apparatus for ensuring that atrial sense events result from intrinsic P-waves originating in the atria and are not far field R-waves for determining the operating mode of the medical device comprising:
- means for sensing the atrial electrocardiogram from at least one electrode positioned in sensing relation to the patient's atria;
- means for detecting an atrial sense event comprising one of the P-wave or far field R-wave in the atrial electrogram;
- means for sensing the ventricular electrogram from at least one electrode positioned in sensing relation to the patient's ventricle;
- means for detecting a ventricular sense event comprising the R-wave in the ventricular electrogram;
- means for determining the end of the cardiac cycle from successive ventricular sense events;
- means operable during each cardiac cycle for discriminating intrinsic P-waves from far field R-waves in the atrial electrogram using Hidden Markov Modeling (HMM), wherein the P-wave and far-field R-wave can each be characterized as a state separated by state transitions in a hidden state sequence and wherein there are discrete probabilities that the states will transition from one to the other in a predetermined order;
- and
- means for determining an operating mode of the implantable medical device based on the HMM discrimination of the atrial sense events as intrinsic P-waves or far field R-waves.
Dependencies are inferred from the claim text.