Risk stratification based heart failure detection algorithm
First Claim
1. A system comprising:
- one or more ambulatory medical devices, wherein a first ambulatory medical device includes a heart sound sensor configured to sense an S3 heart sound of a subject; and
a processor, wherein the processor includes;
a control module configured to;
detect worsening heart failure (WHF) for the subject using a WHF detection scheme, wherein the WHF detection scheme includes comparing one or more measured heart failure (HF) physiological parameter parameters to a WHF detection threshold; and
store, in the memory, an alert of prediction that the subject will experience a WHF event when the one or more measured HF physiological parameter satisfies the WHF detection scheme; and
a risk analysis module configured to;
measure a first physiological parameter of the sensed S3 heart sound, wherein the first physiological parameter is distinct from the one or more measured HF physiological parameter parameters;
determine a HF risk score for the subject according to the at least one measured first physiological parameter in response to detecting the change, and determine whether the HF risk score indicates high risk for WHF or low risk for WHF; and
adjust one or more of the WHF detection scheme threshold, a weighting of the one or more measured HF physiological parameters, or a number of the one or more measured HF parameters that are compared to the WHF detection threshold according to the determined HF risk score to increase sensitivity of the WHF detection scheme when high risk for WHF is indicated and increase specificity of the WHF detection scheme when low risk for WHF is indicated;
wherein the one or more measured HF physiological parameters includes at least one of heart rate (HR), respiration rate (RR), tidal volume (TV), intrathoracic impedance (ITTI), or one or more of heart sound (HS) timing or amplitude distinct from the measured first physiological parameter.
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Abstract
A system comprises a risk analysis module and a worsening heart failure (WHF) detection module. The risk analysis module measures at least one first physiological parameter of a subject using a physiological sensor of an ambulatory medical device, and determines a heart failure (HF) risk score for the subject according to the at least one measured first physiological parameter. The HF risk score indicates susceptibility of the subject to experiencing a HF event. The WHF detection module measures at least one second physiological parameter of the subject using the same or different physiological sensor, and generates an indication of prediction that the subject will experience a WHF event when the at least one second physiological parameter satisfies a WHF detection algorithm. The risk analysis module adjusts generation of the indication by the WHF detection algorithm according to the determined HF risk score.
121 Citations
20 Claims
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1. A system comprising:
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one or more ambulatory medical devices, wherein a first ambulatory medical device includes a heart sound sensor configured to sense an S3 heart sound of a subject; and
a processor, wherein the processor includes;a control module configured to; detect worsening heart failure (WHF) for the subject using a WHF detection scheme, wherein the WHF detection scheme includes comparing one or more measured heart failure (HF) physiological parameter parameters to a WHF detection threshold; and store, in the memory, an alert of prediction that the subject will experience a WHF event when the one or more measured HF physiological parameter satisfies the WHF detection scheme; and a risk analysis module configured to; measure a first physiological parameter of the sensed S3 heart sound, wherein the first physiological parameter is distinct from the one or more measured HF physiological parameter parameters; determine a HF risk score for the subject according to the at least one measured first physiological parameter in response to detecting the change, and determine whether the HF risk score indicates high risk for WHF or low risk for WHF; and adjust one or more of the WHF detection scheme threshold, a weighting of the one or more measured HF physiological parameters, or a number of the one or more measured HF parameters that are compared to the WHF detection threshold according to the determined HF risk score to increase sensitivity of the WHF detection scheme when high risk for WHF is indicated and increase specificity of the WHF detection scheme when low risk for WHF is indicated; wherein the one or more measured HF physiological parameters includes at least one of heart rate (HR), respiration rate (RR), tidal volume (TV), intrathoracic impedance (ITTI), or one or more of heart sound (HS) timing or amplitude distinct from the measured first physiological parameter. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A method of operation of a medical device system, the method comprising:
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sensing an S3 heart sound of a subject using a heart sound sensor of a first ambulatory medical device; detecting worsening heart failure (WHF) for the subject using a WHF detection scheme, wherein the WHF detection scheme that compares one or more measured heart failure (HF) physiological parameter parameters to a WHF detection threshold; measuring at least one a first physiological parameter of the sensed S3 heart sound of a subject using a physiological sensor of an ambulatory medical device, wherein the first S3 heart sound is distinct from the one or more measured HF parameters; detecting a change in the at least one first physiological parameter that exceeds a specified parameter change value; determining a heart failure (HF) risk score for the subject according to the measured at least one first physiological parameter in response to detecting the change, and determine whether the HF risk score indicates high risk for WHF or low risk for WHF; adjusting, by the medical device system, one or more of the WHF detection scheme threshold, a weighting of the one or more measured HF physiological parameters, or a number of the one or more measured HF parameters that are compared to the WHF detection threshold according to a comparison of the determined HF risk score to a HF risk score threshold value to increase sensitivity of the WHF detection scheme when high risk for WHF is indicated and increase specificity of the WHF detection scheme when low risk for WHF is indicated; and presenting, using a display, an alert of prediction that the subject will experience or is experiencing a WHF event when the HF physiological parameter satisfies the adjusted WHF detection scheme using the adjusted detection of WHF; wherein the one or more measured HF physiological parameters includes at least one of heart rate (HR), respiration rate (RR), tidal volume (TV), intrathoracic impedance (ITTI), or one or more of heart sound (HS) timing or amplitude distinct from the measured first physiological parameter. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
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20. A medical system comprising:
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an ambulatory medical device including a heart sound sensor configured to receive a parameter related to an S3 heart sound of a patient; a display; and a processor including; a control module configured to; detect worsening heart failure (WHF) using a WHF detection scheme based on one or more heart failure (HF) physiological parameter parameters of the patient satisfying a WHF detection threshold; and a risk analysis module configured to; receive the parameter related to the S3 heart sound from the ambulatory medical device; and determine a risk category for worsening heart failure (WHF) based on the parameter related to the S3 heart sound, including a high risk category for WHF and a low risk category for WHF; re-determine the risk when detecting a change in the a parameter related to a S3 heart sound that exceeds a specified parameter change value;
wherein the control module is further configured to;adjust the WHF detection scheme according to the re-determined determined risk category by changing one or more of the WHF detection criteria for the HF physiological parameter threshold, a weighting of the one or more measured HF physiological parameters, or a number of the one or more measured HF parameters that are compared to the WHF detection threshold to increase sensitivity of the WHF detection scheme when the high risk category for WHF is indicated and increase specificity of the WHF detection scheme when the low risk category for WHF is indicated; receive a measure related to the HF physiological parameter of the patient from the ambulatory medical device; and present, using the display, an alert that the subject will experience or is experiencing a WHF event when the HF physiological parameter satisfies using the adjusted detection of WHF detection scheme; wherein the one or more measured HF physiological parameters includes at least one of heart rate (HR), respiration rate (RR), tidal volume (TV), intrathoracic impedance (ITTI), or one or more of heart sound (HS) timing or amplitude distinct from the measured first physiological parameter.
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Specification