Detecting or validating a detection of a state change from a template of heart rate derivative shape or heart beat wave complex
Methods, systems, and apparatus for detecting and/or validating a detection of a state change by matching the shape of one or more of an cardiac data series, a heart rate variability data series, or at least a portion of a heart beat complex, derived from cardiac data, to an appropriate template.
1. A method for indicating an occurrence of an epileptic seizure, comprising:
obtaining a time series of heart beat complex data from a patient;
determining at least one heart beat complex shape parameter for each of a plurality of heart beat complexes in a moving window comprising a portion of said time series;
comparing said at least one heart beat complex shape parameter for each of said plurality of heart beat complexes in said moving window to a first reference heart beat complex shape template;
indicating an occurrence of an epileptic seizure based upon a determination that a threshold fraction of said at least one heart beat complex shape parameters of said plurality of heart beat complexes in said moving window fail to match said first reference heart beat complex shape template; and
in response to said indicating, performing at least one further action selected from providing a warning;
logging at least one of said indicating, the time of said indicating, and a seizure severity metric; and
initiating at least one therapy to treat said epileptic seizure.
2. The method of claim 1 , wherein said at least one therapy is selected from:
applying an electrical signal to a neural structure of the patient, wherein said neural structure is selected from a portion of a brain structure of the patient, a portion of a cranial nerve of a patient, a portion of a spinal cord of a patient, a portion of a sympathetic nerve structure of the patient, a portion of a parasympathetic nerve structure of the patient, and a portion of a peripheral nerve of the patient;
delivering a drug to a patient; and
cooling a neural structure of a patient.
3. The method of claim 1 , wherein determining at least one heart beat complex shape parameter comprises determining a plurality of heart beat complex shape parameters defining a shape of each of a plurality of heart beat complexes in said time series; and wherein said comparing comprises comparing said plurality of heart beat complex shape parameters for each of said plurality of complexes to a corresponding plurality of reference heart beat complex shape parameters defining said first reference heart beat complex shape template.
4. The method of claim 1 , wherein said first reference heart beat complex shape template is selected from one of a non-ictal heart beat complex template, an ictal heart beat complex template, and a post-ictal heart beat complex template.
5. The method of claim 1 , wherein determining at least one heart beat complex shape parameter comprises using ECG data to determine a heart beat complex shape for each of a plurality of heart beat complexes in said time series, and wherein said first reference heart beat complex shape template comprises a reference non-ictal PQRST complex template.
6. The method of claim 5 , wherein said first reference non-ictal PQRST complex template is a composite PQRST complex template constructed from a plurality of non-ictal PQRST complexes of said patient.