Assessing autonomic activity using baroreflex analysis

Patent metadata

Field	Value
Publication number	US-9949668-B2
Application number	US-201213367924-A
Country	US
Kind code	B2
Filing date	Feb 7, 2012
Priority date	Jan 10, 2006
Publication date	Apr 24, 2018
Grant date	Apr 24, 2018

Abstract

A method involves implantably detecting changes in posture of a patient's body. Baroreflex responses to the posture changes are determined. An autonomic tone of the patient is determined based on the baroreflex responses. Based on the autonomic tone, various patient susceptibilities to disease may be determined, including susceptibilities to heart disease, arrhythmia, and/or sudden cardiac death.

First claim

What is claimed is:

1. A method, comprising:
detecting a change in posture of a patient's body using a posture sensor;
determining autonomic imbalance of the patient using an implantable medical device, wherein determining the autonomic imbalance of the patient includes performing a baroreflex sensitivity analysis (BSA) based on blood pressure and cardiac signals measured during a time period corresponding to the change in posture, and performing the BSA includes measuring intervals between heartbeats at least during the time period corresponding to the change in posture and determining a rate of change of systolic blood pressure relative to the intervals during the time period corresponding to the change in posture;
delivering therapeutic electrical stimulation from the implantable medical device to the heart of the patient; and
modifying the therapeutic electrical stimulation using an outcome of the BSA.

2. The method of claim 1 , wherein performing the BSA comprises measuring the patient's heart rate during time periods corresponding to the change in posture.

3. The method of claim 2 , wherein performing the BSA further comprises measuring the patient's blood pressure during the time periods corresponding to the change in posture.

4. The method of claim 3 , wherein measuring the blood pressure of the patient's body comprises measuring the blood pressure via a force transducer sensitive to displacement of a blood vessel.

5. The method of claim 4 , wherein measuring the blood pressure of the patient's body via a force transducer comprises measuring the blood pressure via at least one of a blood-vessel-implantable stent-like transducer and a cuff transducer placed around a blood vessel.

6. The method of claim 5 , wherein measuring the blood pressure of the patient's body via the stent-like transducer comprises measuring the blood pressure from the stent-like transducer implanted in a vein that is paralleled by an artery.

7. The method of claim 1 , further comprising forming a baseline data set from long-term measurements of posture changes and baroreflex responses.

8. The method of claim 1 , further comprising forming a threshold for diagnostic alarm based on the baseline data set.

9. The method of claim 1 , wherein performing the BSA comprises performing a power spectral analysis on the intervals between the heartbeats.

10. The method of claim 1 , further comprising determining the patient's susceptibility to heart disease based on the autonomic imbalance.

11. The method of claim 10 , wherein determining the patient's susceptibility to heart disease comprises determining the patient's susceptibility to arrhythmia based on the autonomic imbalance.

12. The method of claim 10 , wherein determining the patient's susceptibility to heart disease comprises determining the patient's susceptibility to sudden cardiac death based on the autonomic imbalance.

13. The method of claim 1 , wherein detecting the change in posture of the patient's body using the posture sensor comprises using a posture sensor contained within the implantable medical device.

14. The method of claim 13 , wherein detecting the change in posture of the patient's body comprises detecting an orientation of the implantable medical device.

15. The method of claim 1 , comprising measuring the blood pressure using a blood pressure sensor contained within the implantable medical device.

16. The method of claim 1 , wherein measuring the intervals between heartbeats comprises measuring the intervals between heartbeats using a heart rate sensor contained within the implantable medical device, and detecting the change in posture of the patient's body using the posture sensor comprises using a posture sensor contained within the implantable medical device, and comprising measuring the blood pressure using a blood pressure sensor contained within the implantable medical device.

17. The method of claim 16 , comprising triggering continuous monitoring of the posture of the patient's body, the intervals between heartbeats, and the blood pressure in response to the change in posture.

Assignees

• Zhang Yunlong
• Schwartz Mark
• Cardiac Pacemakers Inc

Inventors

• Zhang Yunlong
• Schwartz Mark

Classifications

• A61B5/6876

  Blood vessel · CPC title

• A61B5/4047

  afferent nerves, i.e. nerves that relay impulses to the central nervous system · CPC title

• A61B2562/0219

  Inertial sensors, e.g. accelerometers, gyroscopes, tilt switches · CPC title

• A61B5/103 Primary

  Measuring devices for testing the shape, pattern, {colour,} size or movement of the body or parts thereof, for diagnostic purposes (measuring instruments specially adapted for dentistry A61C19/04) · CPC title

• A61B5/6862

  Stents · CPC title