Method and apparatus for detecting atrial filling pressure

• US 8,403,860 B2
• Filed: 10/26/2011
• Issued: 03/26/2013
• Est. Priority Date: 12/30/2002
• Status: Expired due to Fees

• Current Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Original Assignee: Cardiac Pacemakers Incorporated (Boston Scientific Corporation)
• Inventors: Patangay, Abhilash, Siejko, Krzysztof Z.
• Primary Examiner(s): STOKLOSA, JOSEPH A
• Application Number:
  US13/282,143
• Publication Number:
  US 20120041317A1
• Time in Patent Office: 517 Days
• Field of Search: 600/528
• US Class Current: 600/528
• 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 7/00 Instruments for auscultation
• CPC Class Codes: A61N 1/36514 controlled by a physiological quantity other than heart potential, e.g. blood pressure controlled by two or more physical parameters A61N1/36585
• CPC Class Codes: A61N 1/36528 the parameter being measured by means of ultrasound

Abstract

A cardiac rhythm management system provides for ambulatory monitoring of hemodynamic performance based on quantitative measurements of heart sound related parameters for diagnostic and therapeutic purposes. Monitoring of such heart sound related parameters allows the cardiac rhythm management system to determine a need for delivering a therapy and/or therapy parameter adjustments based on conditions of a heart. This monitoring also allows a physician to observe or assess the hemodynamic performance for diagnosing and making therapeutic decisions. Because the conditions of the heart may fluctuate and may deteriorate significantly between physician visits, the ambulatory monitoring, performed on a continuous or periodic basis, ensures a prompt response by the cardiac rhythm management system that may save a life, prevent hospitalization, or prevent further deterioration of the heart.

Claims

1. A system comprising:

an implantable medical device, including;

a heart sound sensor, configured to sense a heart sound signal of a heart;

a heart sound detector, coupled to the heart sound sensor, the heart sound detector configured to detect at least one parameter using the heart sound signal; and

a processor, coupled to the heart sound detector, the processor configured to distinguish between at least two atrial filling pressure magnitudes using the at least one parameter, wherein the at least one parameter is different from each of the at least two atrial filling pressure magnitudes being distinguished.

2. The system of claim 1, wherein the at least two atrial filling pressure magnitudes includes a high atrial filling pressure, wherein the high atrial filling pressure includes an atrial filling pressure above a threshold.

3. The system of claim 2, wherein the threshold includes an absolute pressure threshold of 20 mmHg.

4. The system of claim 2, wherein the threshold includes an absolute pressure threshold of 25 mmHg.

5. The system of claim 2, wherein the threshold includes a population-based threshold.

6. The system of claim 1, wherein the at least one parameter is indicative of a left atrial filling pressure.

7. The system of claim 1, wherein the at least one parameter includes at least one of an amplitude of a third heart sound (S3), a split second heart sound (S2) time interval, an S2-S3 time interval, or a normalized amplitude or interval of at least one measurement, feature, or characteristic of the heart sound signal.

8. The system of claim 1, wherein the implantable medical device includes a cardiac sensor, coupled to the heart sound detector, the cardiac sensor configured to sense a cardiac signal of the heart;

and

wherein the heart sound detector is configured to detect the at least one parameter using the heart sound signal and the cardiac signal.

9. The system of claim 1, including:

a posture sensor, coupled to the processor, the posture sensor configured to sense a posture signal; and

wherein the processor is configured to distinguish between the at least two atrial filling pressure magnitudes using the posture signal.

10. A method comprising:

sensing a heart sound signal of a heart using an implanted heart sound sensor;

detecting at least one parameter using the heart sound signal; and

distinguishing between at least two atrial filling pressure magnitudes using the at least one parameter, wherein the at least one parameter is different from each of the at least two atrial filling pressure magnitudes being distinguished.

11. The method of claim 10, wherein the at least two atrial filling pressure magnitudes includes a high atrial filling pressure, wherein the high atrial filling pressure includes an atrial filling pressure above a threshold.

12. The method of claim 11, wherein the threshold includes an absolute pressure threshold of 20 mmHg.

13. The method of claim 11, wherein the threshold includes an absolute pressure threshold of 25 mmHg.

14. The method of claim 11, wherein the threshold includes a population-based threshold.

15. The method of claim 10, wherein the detecting the at least one parameter using the heart sound signal includes detecting a left atrial filling pressure using the heart sound signal.

16. The method of claim 10, wherein the detecting the at least one parameter using the heart sound signal includes detecting at least one of an amplitude of a third heart sound (S3), a split second heart sound (S2) time interval, an S2-S3 time interval, or a normalized amplitude or interval of at least one measurement, feature, or characteristic of the heart sound signal.

17. The method of claim 10, including:

sensing a cardiac signal of the heart using an implantable cardiac sensor; and

wherein the detecting the at least one parameter includes using the heart sound signal and the cardiac signal.

18. The method of claim 10, including:

sensing a posture signal using a posture sensor; and

wherein the distinguishing between the at least two atrial filling pressure magnitudes includes using the posture signal.

19. The method of claim 10, including generating an alert using an atrial filling pressure magnitude distinguished using the at least one parameter.

20. A system comprising:

an implantable medical device, including;

a heart sound sensor, configured to sense a heart sound signal of a heart;

a heart sound detector, coupled to the heart sound sensor, the heart sound detector configured to detect at least one parameter using the heart sound signal; and

a processor, coupled to the heart sound detector, the processor configured to distinguish between at least two atrial filling pressure magnitudes using the at least one parameter, wherein the at least one parameter is different from each of the at least two atrial filling pressure magnitudes being distinguished, wherein the at least two atrial filling pressure magnitudes includes a high atrial filling pressure, and wherein the high atrial filling pressure includes an atrial filling pressure above an absolute pressure threshold of 25 mmHg.