Systems and Methods for Anemia Detection, Monitoring, and Treatment

• US 20100249865A1
• Filed: 03/23/2010
• Published: 09/30/2010
• Est. Priority Date: 03/24/2009
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Hatlestad, John D., Zhang, Yunlong, Mi, Bin
• Granted Patent: US 8,480,581 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61B 5/0031 Implanted circuitry
• CPC Class Codes: A61B 5/02028 Determining haemodynamic parameters not otherwise provided for, e.g. cardiac contractility or left ventricular ejection fraction
• CPC Class Codes: A61B 5/02035 Determining blood viscosity
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/14535 for measuring haematocrit
• CPC Class Codes: A61B 5/417 the bone marrow
• CPC Class Codes: A61N 1/36007 of urogenital or gastrointestinal organs, e.g. for incontinence control
• 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 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371

Abstract

Methods and systems for implantably determining a patient'"'"'s anemia status and treating anemia are described. Blood viscosity is compared one or more thresholds to determine a patient'"'"'s anemia status. Therapy, in the form of electrical stimulation therapy or administration of a pharmaceutical delivered to the patient'"'"'s kidneys or hypothalamus is controlled based on the anemia status.

Claims

1. A method of operating an implantable medical system, the method comprising:

sensing blood viscosity using a sensor configured for implantation within a blood vessel or heart;

comparing the blood viscosity to one or more thresholds respectively associated with one or more hematocrit levels;

determining an anemia status of a patient based on comparison of the blood viscosity to the one or more thresholds; and

controlling an electrical stimulation therapy delivered to one or both kidneys or a hypothalamus of the patient based at least in part on the anemia status.

2. The method of claim 1, further comprising:

trending the anemia status of the patient over time, wherein controlling the electrical stimulation therapy comprises controlling the electrical stimulation therapy based on a rate of change in the anemia status trend.

3. The method of claim 1, further comprising:

sensing blood temperature; and

compensating the blood viscosity using the blood temperature.

4. The method of claim 1, further comprising:

trending the anemia status of the patient over time; and

monitoring a progression of heart failure based on the anemia status trend.

5. The method of claim 4, further comprising modifying a heart failure therapy based on the anemia status trend.

6. The method of claim 4, further comprising adjusting biventricular pacing based on the anemia status trend.

7. The method of claim 1, wherein:

determining the anemia status comprises detecting hemodilutional anemia; and

further comprising detecting an onset of a heart failure decompensation event based on the detection of the hemodilutional anemia.

8. The method of claim 1, further comprising:

sensing thoracic impedance; and

detecting an onset of a heart failure decompensation event based on the anemia status and the thoracic impedance.

9. The method of claim 1, wherein controlling the electrical stimulation therapy comprises controlling the electrical stimulation therapy based in part on an evaluation of thromboembolism risk.

10. The method of claim 1, wherein controlling the electrical stimulation therapy comprises electrically stimulating the kidneys using a signal having a frequency between about 0.1 Hz and about 10 kHz.

11. The method of claim 1, wherein controlling the electrical stimulation therapy comprises electrically stimulating the kidneys using a signal having sufficient amplitude to produce an electric field strength of about 0.1 V/cm and about 10 V/cm volts per centimeter.

12. A medical system, comprising:

an implantable sensor including circuitry configured to sense blood viscosity and to generate a signal modulated by the blood viscosity;

implantable circuitry configured to receive the blood viscosity signal and to store the blood viscosity; and

an anemia module coupled to the implantable circuitry, the anemia module configured to compare the blood viscosity to one or more thresholds associated with hematocrit, to determine an anemia status of a patient based on the comparison, and to store a trend of the anemia status over time.

13. The medical system of claim 12, further comprising a heart failure diagnostics module configured to detect an onset of heart failure decompensation based on the anemia status trend.

14. The medical system of claim 12, wherein the implantable circuitry and the anemia module are incorporated in an implantable cardiac therapy device, the cardiac therapy device further comprising a cardiac therapy controller configured to control a cardiac pacing therapy based on the anemia status trend.

15. The medical system of claim 12, wherein the anemia module is further configured to generate an alert signal based on the anemia status trend.

16. The medical system of claim 12, wherein the anemia module is further configured to evaluate thromboembolism risk and to generate an alert signal based on the thromboembolism risk.

17. An implantable medical system, comprising:

an implantable sensor configured to sense blood viscosity;

an anemia module configured to compare the blood viscosity to one or more thresholds respectively associated with one or more hematocrit levels and to determine an anemia status of a patient based on comparison of the blood viscosity to the one or more thresholds; and

a therapy module configured to deliver therapy to the patient based on the anemia status or blood viscosity.

18. The medical system of claim 17, wherein:

the anemia module is configured to evaluate thromboembolism risk; and

the therapy module is configured to deliver therapy to the patient based on the thromboembolism risk.

19. The medical system of claim 17, wherein the therapy module delivers a drug.

20. The medical system of claim 17, wherein the therapy module comprises an electrical stimulator configured to deliver electrical stimulation therapy to one or both kidneys.

21. The medical system of claim 20, wherein the therapy module is configured to provide cardiac resynchronization pacing for heart failure.

22. The medical system of claim 17, wherein the anemia module is configured to detect an onset of heart failure decompensation based on the anemia status and to generate an alert signal in response to detection of the onset of heart failure decompensation.

23. The medical system of claim 17, wherein the anemia module is configured to generate an alert signal based on the anemia status.

24. The medical system of claim 17, wherein the therapy module is configured to electrically stimulate a hypothalamus.

25. The medical system of claim 17, wherein the implantable sensor comprises an acoustic sensor.