Osmometric Heart Monitoring Device and Methods

• US 20090024177A1
• Filed: 07/18/2007
• Published: 01/22/2009
• Est. Priority Date: 07/18/2007
• Status: Active Grant

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Qu, Jihong, Mokelke, Eric A., Kane, Michael John, Shuros, Allan Charles
• Granted Patent: US 7,734,349 B2
• Time in Patent Office: Days
• US Class Current: 607/22
• CPC Class Codes: A61B 2562/02 Details of sensors specially adapted for in-vivo measurements
• CPC Class Codes: A61B 5/0006 ECG or EEG signals
• 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 5/076 Permanent implantations telemetry using implanted circuitry A61B5/0031; implanted stimulators for therapy A61N1/3605, A61N1/362, A61N1/372
• 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 5/4869 Determining body composition
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/36521 the parameter being derived from measurement of an electrical impedance
• CPC Class Codes: A61N 1/36557 controlled by chemical substances in blood
• CPC Class Codes: A61N 1/3702 Physiological parameters A61N1/365 takes precedence; evoked response A61N1/371
• CPC Class Codes: G01N 13/04 Investigating osmotic effects

Abstract

Embodiments of the invention are related to monitoring devices and methods with osmometric sensors, amongst other things. In an embodiment, the invention includes an implantable heart failure monitoring system including an osmometric sensor, the osmometric sensor configured to generate a signal corresponding to the osmotic strength of a bodily fluid, and a controller in communication with the osmometric sensor, the controller configured to receive and process the signal corresponding to the osmotic strength of a bodily fluid. Other aspects and embodiments are provided herein.

Claims

1. An implantable heart failure monitoring system comprising:

an osmometric sensor, the osmometric sensor configured to generate a signal corresponding to the osmotic strength of a bodily fluid, and

a controller in communication with the osmometric sensor, the controller configured to receive and process the signal corresponding to the osmotic strength of a bodily fluid.

2. The implantable heart failure monitoring system of claim 1, further comprising a lead comprising a lead body and a conductor disposed within the lead body, the conductor in electrical communication with the osmometric sensor and the controller.

3. The implantable heart failure monitoring system of claim 2, the osmometric sensor disposed on the lead body.

4. The implantable heart failure monitoring system of claim 2, the lead further comprising an electrode configured to interface with a target tissue.

5. The implantable heart failure monitoring system of claim 4, the controller further configured to generate electrical stimulation pulses to be delivered to the target tissue through the electrode.

6. The implantable heart failure monitoring system of claim 1, the controller configured to generate a warning notification if the osmotic strength of the bodily fluid falls below a preselected threshold level.

7. The implantable heart failure monitoring system of claim 1, the system configured to modulate a cardiac pacing rate based on the signal generated by the osmometric sensor.

8. The implantable heart failure monitoring system of claim 7, the system configured to modulate a minimum cardiac pacing rate based on the signal generated by the osmometric sensor.

9. The implantable heart failure monitoring system of claim 1, the osmometric sensor comprising

a wall member defining an enclosed volume, the wall member comprising a semi-permeable membrane;

and

a solution comprising a solvent and a solute, the solution disposed within the enclosed volume;

the semi-permeable membrane permeable to the solvent and impermeable to the solute.

10. The implantable heart failure monitoring system of claim 9, the solute selected from the group consisting of sodium chloride, calcium chloride, magnesium chloride, potassium chloride, manganese chloride, and albumen.

11. The implantable heart failure monitoring system of claim 9, the semi-permeable membrane comprising a polymer.

12. The implantable heart failure monitoring system of claim 9, further comprising a first pressure sensor configured to sense the pressure within the enclosed volume.

13. The implantable heart failure monitoring system of claim 12, further comprising a second pressure sensor configured to sense the pressure outside of the enclosed volume.

14. The implantable heart failure monitoring system of claim 1, the osmometric sensor comprising a first electrode and a second electrode, the osmometric sensor configured to pass a current between the first electrode and the second electrode.

15. The implantable heart failure monitoring system of claim 1, the osmometric sensor comprising a sensor configured to measure concentrations of one or more chemical species selected from the group consisting of sodium ions, potassium ions, glucose, and blood urea nitrogen (BUN).

16. An implantable osmotic heart monitoring system comprising:

an osmotic pH sensor, the osmotic pH sensor configured to generate a signal corresponding to pH of a bodily fluid, the osmotic pH sensor comprising

a wall member defining an enclosed volume, the wall member comprising a semi-permeable membrane; and

a solution comprising a solvent and a solute, the solution disposed within the enclosed volume, the solute configured to change osmotic strength in a pH range of between about 7.3 and about 7.5;

the semi-permeable membrane permeable to the solvent and impermeable to the solute; and

a controller in communication with the osmotic pH sensor.

17. The implantable osmotic heart monitoring system of claim 16, the solute having a pKa of between about 6.0 and about 10.0.

18. The implantable osmotic heart monitoring system of claim 16, the controller configured to generate a warning notification if the pH falls below a preselected threshold level.

19. The implantable osmotic heart failure monitoring system of claim 16, further comprising a lead comprising a lead body and a conductor disposed within the lead body, the conductor in electrical communication with the osmotic pH sensor and the controller.

20. The implantable osmotic heart failure monitoring system of claim 19, the osmotic pH sensor disposed on the lead body.

21. The implantable osmotic heart failure monitoring system of claim 20, the lead further comprising an electrode configured to interface with a target tissue.

22. The implantable osmotic heart failure monitoring system of claim 21, the controller further configured to generate electrical stimulation pulses to be delivered to the target tissue through the electrode.

23. The implantable osmotic heart failure monitoring system of claim 16, the preselected threshold level comprising a pH of 7.3.

24. The implantable osmotic heart failure monitoring system of claim 16, further comprising a first pressure sensor configured to sense the pressure within the enclosed volume.

25. The implantable osmotic heart failure monitoring system of claim 24, further comprising a second pressure sensor configured to sense the pressure outside of the enclosed volume.