Method and apparatus for monitoring and optimizing atrial function

• US 20070083243A1
• Filed: 10/07/2005
• Published: 04/12/2007
• Est. Priority Date: 10/07/2005
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Prakash, Rajan, Chinchoy, Edward, Mullen, Thomas
• Granted Patent: US 7,869,876 B2
• Time in Patent Office: Days
• US Class Current: 607/17
• CPC Class Codes: A61B 2562/0219 Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches
• CPC Class Codes: A61B 5/1107 Measuring contraction of parts of the body, e.g. organ, muscle apparatus for measuring work or force in general G01L
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• 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 1/36542 controlled by body motion, e.g. acceleration
• CPC Class Codes: A61N 1/368 comprising more than one electrode co-operating with different heart regions A61N1/3622, A61N1/3627 take precedence
• CPC Class Codes: A61N 1/3682 with a variable atrioventricular delay

Abstract

A method for use in an implantable medical device, comprising: sensing a signal corresponding to ventricular wall acceleration; and determining a metric of atrial function using the ventricular wall acceleration signal. The method includes sensing the ventricular wall acceleration signal during at least during a sensing window corresponding to a ventricular filling phase.

Claims

1. A method for use in an implantable medical device, comprising:

sensing a signal corresponding to ventricular wall acceleration; and

determining a metric of atrial function using the ventricular wall acceleration signal.

2. A method according to claim 1, wherein sensing the ventricular wall acceleration signal includes setting a sensing window corresponding to a ventricular filling phase.

3. A method according to claim 1, wherein sensing the ventricular wall acceleration signal includes sensing a signal corresponding to left ventricular wall acceleration.

4. A method according to claim 1, wherein determining a metric of atrial function includes detecting a first ventricular filling phase peak and detecting if a second ventricular filling phase peak follows the first ventricular filling phase peak.

5. A method according to claim 1, wherein determining a metric of atrial function includes any of:

determining a time between a first ventricular filling phase peak and a second ventricular filling phase peak, determining an amplitude of the first ventricular filling phase peak, determining an amplitude of the second ventricular filling phase peak, determining a morphological signature, determining a slope, and determining the time of an inflection point.

6. A method according to claim 1, further comprising:

iteratively adjusting an AV delay control parameter over a range of settings;

determining the metric of atrial function for each AV delay setting; and

determining an optimal AV delay setting based on the atrial function metric.

7. An implantable medical device, comprising:

means for generating a signal corresponding to ventricular wall acceleration;

means for receiving the signal from the generating means;

means for deriving a metric of atrial function using the signal; and

means for storing the atrial function metric.

8. An implantable medical device according to claim 7, wherein the means for generating a signal includes an accelerometer.

9. An implantable medical device according to claim 7, wherein the signal corresponds to left ventricular wall acceleration.

10. An implantable medical device according to claim 7, further including means for setting a sensing window corresponding to a ventricular filling phase.

11. An implantable medical device according to claim 7, wherein the means for deriving the atrial function metric includes means for detecting a first ventricular filling phase peak and means for detecting if a second ventricular filling phase peak follows the first ventricular filling phase peak.

12. An implantable medical device according to claim 7, wherein the means for deriving the atrial function metric includes any of:

means for determining a time interval between a first ventricular filling phase peak and a second ventricular filling phase peak, means for determining a first ventricular filling phase peak amplitude, means for determining a second ventricular filling phase peak amplitude, means for determining a morphological signature, means for determining a slope, and means for determining the time of an inflection point.

13. An implantable medical device according to claim 7, further comprising:

an atrial electrode for delivering a stimulation pulse in an atrial chamber;

a ventricular electrode for delivering a stimulation pulse in a ventricular chamber;

a pulse generator adapted for electrical connection to the atrial electrode and the ventricular electrode for generating an atrial stimulation pulse delivered to the atrial chamber by the atrial electrode and for generating a ventricular stimulation pulse delivered to the ventricular chamber by the ventricular electrode;

a timing control module for setting an AV delay based on the atrial function metric for controlling the time interval between the atrial pulse and the ventricular pulse.

14. An implantable medical device according to claim 13, further including a coronary sinus lead and wherein the ventricular electrode couples to the coronary sinus lead.

15. An implantable medical device according to claim 14, wherein the coronary sinus lead includes the means for generating a signal corresponding to ventricular wall acceleration.

16. A computer readable medium for storing a set of instructions which when implemented in an implantable medical device system cause the system to:

sense a signal corresponding to ventricular wall acceleration; and

determine a metric of atrial function using the ventricular wall acceleration signal.

17. A computer readable medium according to claim 16, further including instruction for setting a sensing window corresponding to a ventricular filling phase.

18. A computer readable medium according to claim 16, wherein the signal corresponds to left ventricular free wall acceleration.

19. A computer readable medium according to claim 16, the instructions for determining a metric of atrial function include instructions for detecting a first ventricular filling phase peak and instructions for detecting if a second ventricular filling phase peak follows the first ventricular filling phase peak.

20. A computer readable medium according to claim 16, wherein the instruction for determining a metric of atrial function include instructions for any of:

determining a time between a first ventricular filling phase peak and a second ventricular filling phase peak, determining an amplitude of the first ventricular filling phase peak, and determining an amplitude of the second ventricular filling phase peak.

21. A computer readable medium according to claim 16, further comprising instructions for causing the system to:

adjust an AV delay control parameter over a range of settings; and

determine the metric of atrial function for each AV delay setting; and

determining an optimal AV delay setting based on the atrial function metric.