Hemodynamic performance enhancement through asymptomatic diaphragm stimulation

• US 10,315,035 B2
• Filed: 04/11/2018
• Issued: 06/11/2019
• Est. Priority Date: 12/19/2012
• Status: Active Grant

• Current Assignee: Viscardia, Inc.
• Original Assignee: Viscardia, Inc.
• Inventors: Bauer, Peter T.
• Primary Examiner(s): Fairchild, Mallika D
• Application Number:
  US15/950,774
• Publication Number:
  US 20180229034A1
• Time in Patent Office: 426 Days
• CPC Class Codes: A61B 2562/063 in a linear array
• CPC Class Codes: A61B 5/02438 with portable devices, e.g. worn by the patient
• CPC Class Codes: A61B 5/113 occurring during breathing
• CPC Class Codes: A61B 5/349 Detecting specific parameters of the electrocardiograph cycle
• CPC Class Codes: A61B 5/352 Detecting R peaks, e.g. for synchronising diagnostic apparatus; Estimating R-R interval
• CPC Class Codes: A61B 5/4836 Diagnosis combined with treatment in closed-loop systems or methods A61B5/0036 takes precedence
• CPC Class Codes: A61B 5/686 Permanently implanted devices, e.g. pacemakers, other stimulators, biochips A61B5/6861 takes precedence
• CPC Class Codes: A61B 5/6867 specially adapted to be attached or implanted in a specific body part A61B5/6847 takes precedence
• CPC Class Codes: A61B 5/721 using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured
• CPC Class Codes: A61B 5/7246 using correlation, e.g. template matching or determination of similarity
• CPC Class Codes: A61N 1/3601 of respiratory organs
• 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 1/36585 controlled by two or more physical parameters

Abstract

An implantable system, and methodology, for improving a heart'"'"'s hemodynamic performance featuring (a) bimodal electrodes placeable on the diaphragm, out of contact with the heart, possessing one mode for sensing cardiac electrical activity, and another for applying cardiac-cycle-synchronized, asymptomatic electrical stimulation to the diaphragm to trigger biphasic, diaphragmatic motion, (b) an accelerometer adjacent the electrodes for sensing both heart sounds, and stimulation-induced diaphragmatic motion, and (c) circuit structure, connected both to the electrodes and the accelerometer, operable, in predetermined timed relationships to the presences of valid V-events noted in one of sensed electrical and sensed mechanical, cardiac activity, to deliver diaphragmatic stimulation. The circuit structure includes accelerometer-linked computer structure for enabling selective review, for later operational modifications, of stimulation-produced diaphragmatic motions, and in a modified form, may additionally include timing-adjustment substructure capable of making adjustments in the mentioned timed relationships.

Claims

1. An implantable medical system for improving hemodynamic performance of a heart through electrical stimulation of a diaphragm, the implantable medical system comprising

a plurality of electrodes configured to be placed adjacent to or in direct contact with the diaphragm, and to enable the sensing of electrical cardiac activity through the diaphragm and the delivering of electrical stimulation to the diaphragm;

a mechanical sensing structure configured to be place adjacent to or in direct contact with the diaphragm, and to enable the sensing of mechanical cardiac activity through the diaphragm and the sensing of motion activity of the diaphragm; and

a circuit structure coupled to the plurality of electrodes and the mechanical sensing structure and configured to;

obtain sensed cardiac activity corresponding to one of sensed electrical cardiac activity and sensed mechanical cardiac activity,

detect a cardiac event in a cardiac cycle based on the sensed cardiac activity, and

apply an electrical stimulation to at least one of the plurality of electrodes in a timed relationship relative to the detected cardiac event.

2. The implantable medical system of claim 1, wherein the circuit structure is further configured to:

obtain sensed motion activity of the diaphragm resulting from the application of the electrical stimulation;

compare a representation of the sensed motion activity to a reference representation of expected motion activity; and

determine whether the representations are in conformance with each other.

3. The implantable medical system of claim 2, wherein the representation and the reference representation are waveforms.

4. The implantable medical system of claim 2, wherein the reference representation corresponds to motion activity of the diaphragm that maximizes hemodynamic performance of the heart.

5. The implantable medical system of claim 1, wherein the circuit structure is further configured to:

obtain sensed motion activity of the diaphragm resulting from the application of the electrical stimulation; and

record the obtained sensed motion activity.

6. The implantable medical system of claim 1, wherein the mechanical sensing structure is an accelerometer.

7. The implantable medical system of claim 6, wherein the accelerometer is a multi-axis accelerometer.

8. The implantable medical system of claim 1, wherein the cardiac event corresponds to one of a R wave, a Q wave and an S1 heart sound.

9. The implantable medical system of claim 1, wherein the electrical stimulation comprises a single pulse configured to induce a singular asymptomatic motion of the diaphragm.

10. The implantable medical system of claim 9, wherein the singular asymptomatic motion of the diaphragm is characterized by biphasic, caudal-followed-by-cranial motion.

11. The implantable medical system of claim 9, wherein the asymptomatic motion of the diaphragm has a duration of a few tens of milliseconds.

12. The implantable medical system of claim 1, comprising a lead and a housing, wherein:

the plurality of electrodes and the mechanical sensing structure are associated with the lead,

the circuit structure is associated with the housing, and

the lead and the housing are configured to couple together to thereby couple the circuit structure to the plurality of electrodes and the mechanical sensing structure.

13. The implantable medical system of claim 1, comprising a capsule structure, wherein the plurality of electrodes and the mechanical sensing structure and the circuit structure are associated with the capsule structure.

14. A method for improving hemodynamic performance of a heart through electrical stimulation of a diaphragm, the method comprising:

obtaining sensed cardiac activity corresponding to one of electrical cardiac activity sensed through the diaphragm and mechanical cardiac activity sensed through the diaphragm,

detecting a cardiac event in a cardiac cycle based on the sensed cardiac activity, and

applying an electrical stimulation to the diaphragm in a timed relationship relative to the detected cardiac event.

15. The method of claim 14, further comprising:

obtaining sensed motion activity of the diaphragm resulting from the application of the electrical stimulation;

comparing a representation of the sensed motion activity to a reference representation of expected motion activity; and

determining whether the representations are in conformance with each other.

16. The method of claim 14, further comprising:

obtaining sensed motion activity of the diaphragm resulting from the application of the electrical stimulation; and

recording the obtained sensed motion activity.

17. The method of claim 14, wherein electrical cardiac activity is sensed through the diaphragm by a plurality of electrodes adjacent to or in direct contact with the diaphragm.

18. The method of claim 14, wherein mechanical cardiac activity is sensed through the diaphragm by a mechanical sensing structure adjacent to or in direct contact with the diaphragm.

19. The method of claim 14, wherein electrical stimulation is applied to the diaphragm through at least one of a plurality of electrodes adjacent to or in direct contact with the diaphragm.

20. The method of claim 14, wherein motion activity of the diaphragm is sensed by a mechanical sensing structure adjacent to or in direct contact with the diaphragm.