Decongestive therapy titration for heart failure patients using implantable sensor

• US 20080294209A1
• Filed: 05/23/2007
• Published: 11/27/2008
• Est. Priority Date: 05/23/2007
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Thompson, Julie A., Dalal, Yousufali H.
• Granted Patent: US 8,271,080 B2
• Time in Patent Office: Days
• US Class Current: 607/3
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/02055 Simultaneously evaluating both cardiovascular condition and temperature
• CPC Class Codes: A61B 5/021 Measuring pressure in heart or blood vessels A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/0537 Measuring body composition by impedance, e.g. tissue hydration or fat content
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/318 Heart-related electrical modalities, e.g. electrocardiography [ECG]
• CPC Class Codes: A61B 5/4261 Evaluating exocrine secretion production A61B3/101 takes precedence
• CPC Class Codes: A61B 5/4833 Assessment of subject's compliance to treatment
• CPC Class Codes: A61B 5/4839 combined with drug delivery
• CPC Class Codes: A61B 7/04 Electric stethoscopes microphones, acoustic transducers therefor H04R
• CPC Class Codes: A61M 2205/054 with electrotherapy
• CPC Class Codes: A61M 2210/125 Heart
• CPC Class Codes: A61M 5/14276 specially adapted for implantation
• CPC Class Codes: A61M 5/1723 using feedback of body parameters, e.g. blood-sugar, pressure measurement of body parameters A61B5/00
• CPC Class Codes: A61N 1/36114 Cardiac control, e.g. by vagal stimulation stimulating the heart A61N1/362
• CPC Class Codes: A61N 1/3614 based on impedance measurement
• CPC Class Codes: A61N 1/3627 for treating a mechanical deficiency of the heart, e.g. congestive heart failure or cardiomyopathy
• CPC Class Codes: A61N 1/365 controlled by a physiological parameter, e.g. heart potential evoked response A61N1/371
• CPC Class Codes: A61N 1/37258 : Alerting the patient
• CPC Class Codes: G16H 20/00 : ICT specially adapted for therapies or health-improving plans, e.g. for handling prescriptions, for steering therapy or for monitoring patient compliance
• CPC Class Codes: G16H 20/10 : relating to drugs or medications, e.g. for ensuring correct administration to patients
• CPC Class Codes: G16H 20/40 : relating to mechanical, radiation or invasive therapies, e.g. surgery, laser therapy, dialysis or acupuncture
• CPC Class Codes: G16H 40/63 : for local operation

Abstract

Assessing decongestive therapy delivered to a heart failure patient involves use of an implantable sensor configured to sense a physiologic parameter indicative of the patient'"'"'s diuresis status and a processor coupled to the implantable sensor. The sensor may comprise a thoracic fluid sensor, a heart sounds sensor, a cardiac chamber or arterial pressure sensor, a respiration sensor, or a blood chemistry sensor, for example. The processor is configured to determine if a target level of patient diuresis has been achieved based on a relationship between the sensed physiologic parameter and a threshold developed for the patient, and to produce an output in response to determining that the target level of patient diuresis has been achieved. The processor may be disposed in an implantable housing, in a patient-external housing, or in a network server system.

Claims

1. A method for assessing decongestive therapy delivered to a heart failure patient, comprising:

sensing, from within the patient, a physiologic parameter indicative of the patient'"'"'s diuresis status;

determining if a target level of patient diuresis has been achieved based on a relationship between the sensed physiologic parameter and a threshold developed for the patient; and

producing an output in response to determining that the target level of patient diuresis has been achieved.

2. The method of claim 1, further comprising detecting an occurrence of a congestive event, and sensing the physiologic parameter in response to detection of the congestive event.

3. The method of claim 1, wherein the method is performed for chronic diuretic therapy and acute management of emergent diuretic therapy responsive to a congestive event.

4. The method of claim 1, further comprising titrating the decongestive therapy based on the produced output.

5. The method of claim 1, further comprising generating an alert in response to detecting over-diuresis of the patient.

6. The method of claim 1, further comprising generating an alert in response to detecting non-compliance to a drug regimen of the decongestive therapy.

7. The method of claim 1, further comprising generating an alert in response to detecting refractoriness to the decongestive therapy.

8. The method of claim 1, wherein the method is performed in real-time during delivery of the decongestive therapy.

9. The method of claim 1, further comprising adjusting sensing of the physiologic parameter based on one or more of a type of medication administered to the patient for decongestive therapy, a manner of delivering the decongestive therapy, and one or more patient specific conditions.

10. The method of claim 1, wherein the method is performed within the patient.

11. The method of claim 1, wherein at least one of comparing, determining, and producing is performed externally of the patient.

12. The method of claim 1, wherein the relationship between the sensed physiologic parameter and the threshold comprises at least one of:

the sensed physiologic parameter returning to a baseline value established as the threshold;

the sensed physiologic parameter returning to a predetermined percentage or function of a baseline value established as the threshold;

a rate of change of increase or decrease of the sensed physiologic parameter relative to the threshold;

a rate of change of increase or decrease of the sensed physiologic parameter relative to a safe level of patient diuresis established as the threshold;

or

a change of the sensed physiologic parameter that matches a response of the physiologic parameter associated with a prior successful therapy delivered to the patient.

13. The method of claim 1, wherein the physiologic parameter comprises at least one of a thoracic fluid parameter, a thoracic impedance parameter, a heart sounds parameter, a cardiac chamber pressure parameter, an arterial pressure parameter, a respiration parameter, heart rate parameter, heart rate variability parameter, an electrogram conduction pattern parameter, a blood chemistry parameter, a potassium level parameter, a blood perfusion parameter, a blood oxygen saturation parameter, a body extremity temperature parameter, a body extremity perspiration parameter, and a patient weight parameter.

14. The method of claim 1, wherein the threshold is established by a physician.

15. A method for assessing a therapy delivered to a heart failure patient, comprising:

sensing, from within the patient, a physiologic parameter indicative of the patient'"'"'s status responsive to the therapy;

determining if a target level of therapy benefit to the patient has been achieved based on a relationship between the sensed physiologic parameter and a threshold developed for the patient; and

producing a first output in response to determining that the target level of patient benefit has been achieved and a second output in response to determining that the patient is subject to over-therapeuting.

16. The method of claim 15, wherein the therapy comprises a drug therapy.

17. The method of claim 15, wherein the therapy comprises a neurostimulation therapy.

18. The method of claim 15, wherein the therapy comprises a cardiac electrical stimulation therapy.

19. A system for assessing decongestive therapy delivered to a heart failure patient, comprising:

an implantable sensor configured to sense a physiologic parameter indicative of the patient'"'"'s diuresis status; and

a processor coupled to the implantable sensor, the processor configured to determine if a target level of patient diuresis has been achieved based on a relationship between the sensed physiologic parameter and a threshold developed for the patient, and to produce an output in response to determining that the target level of patient diuresis has been achieved.

20. The system of claim 19, wherein the processor is disposed in an implantable housing.

21. The system of claim 19, wherein the processor is disposed in a housing external to the patient.

22. The system of claim 19, wherein the processor is a processor of a network server system.

23. The system of claim 19, wherein the processor is configured to generate an alert signal in response to one or more of detecting over-diuresis of the patient, detecting non-compliance to a drug regimen of the decongestive therapy, and detecting refractoriness to the decongestive therapy.

24. The system of claim 19, wherein the sensor comprises a thoracic fluid sensor.

25. The system of claim 19, wherein the sensor comprises a heart sounds sensor.

26. The system of claim 19, wherein the sensor comprises a cardiac chamber or arterial pressure sensor.

27. The system of claim 19, wherein the sensor comprises a respiration sensor.

28. The system of claim 19, wherein the sensor comprises a blood chemistry sensor.