Real Time Heart Rate Monitoring for Close Loop Control and/or Artificial Pulse Synchronization of Implantable Ventricular Assist Devices

Patent metadata

Field	Value
Publication number	US-2024207600-A1
Application number	US-202218088079-A
Country	US
Kind code	A1
Filing date	Dec 23, 2022
Priority date	Feb 16, 2022
Publication date	Jun 27, 2024
Grant date	—

Abstract

Circulatory support systems and related methods are disclosed in which a ventricular assist device is controlled based on cardiac activity monitored via cardiogram electrodes. A circulatory support system includes a ventricular assist device, cardiogram electrodes, and a controller. The controller processes a cardiogram signal generated via the cardiogram electrodes to determine one or more physiological parameters indicative of an activity level and/or cardiac cycle timing, determines at least one operating parameter for the ventricular assist device based on the one or more physiological parameters, and controls operation of the ventricular assist device in accordance with the at least one operating parameter.

First claim

What is claimed is:

1 . A circulatory support system comprising:
a ventricular assist device configured for pumping blood from a ventricle of a heart of a patient to an artery to supplement or replace pumping of blood by the ventricle to the artery; electrocardiogram electrodes configured to generate an electrocardiogram signal; and a controller comprising at least one processor and a tangible memory device storing non-transitory instructions executable by the at least one processor to cause the at least one processor to:
process the electrocardiogram signal to determine one or more physiological parameters of the patient, wherein the one or more physiological parameters are indicative of an activity level and/or cardiac cycle timing of the patient;
determine at least one operating parameter for the ventricular assist device based on the one or more physiological parameters; and
control operation of the ventricular assist device in accordance with the at least one operating parameter.

2 . The circulatory support system of claim 1 , wherein the at least one operating parameter comprises a reference rotational speed of the ventricular assist device.

3 . The circulatory support system of claim 2 , wherein:
the one or more physiological parameters comprise a heart rate of the patient; and the tangible memory device stores a reference rotational speed lookup table that stores an array of reference rotational speeds for the ventricular assist device corresponding to an array of reference heart rates.

4 . The circulatory support system of claim 3 , wherein the controller is configured so that array of reference rotational speeds and/or the array of reference heart rates can be input into the tangible memory device by a medical professional.

5 . The circulatory support system of claim 2 , wherein:
the one or more physiological parameters comprise a heart rate of the patient; and the tangible memory device stores data that defines a rotational speed for the ventricular assist device as a function of the heart rate of the patient.

6 . The circulatory support system of claim 5 , wherein the controller is configured so that the data that defines the rotational speed of the ventricular assist device as a function of the heart rate of the patient can be input into the tangible memory device by a medical professional.

7 . The circulatory support system of claim 2 , wherein the reference rotational speed of the ventricular assist device is a constant speed rotation rate for the ventricular assist device.

8 . The circulatory support system of claim 2 , wherein:
the reference rotational speed of the ventricular assist device is set to be equal to a first reference rotational speed at a first reference heart rate; the reference rotational speed of the ventricular assist device is set to be equal to a second reference rotational speed at a second reference heart rate; the second reference rotational speed is greater than the first reference rotational speed; and the second reference heart rate is greater than the first reference heart rate.

9 . The circulatory support system of claim 2 , wherein the non-transitory instructions are executable by the at least one processor to cause the at least one processor to operate the ventricular assist device in an artificial pulse mode in which a rotational speed of the ventricular assist device is varied according to a repeating rotational speed profile that is based on the reference rotational speed.

10 . The circulatory support system of claim 9 , wherein each cycle of the repeating rotational speed profile is synchronized with a respective cardiac cycle of the heart.

11 . The circulatory support system of claim 10 , wherein the non-transitory instructions are executable by the at least one processor to further cause the at least one processor to:
process the electrocardiogram signal to identify a time of occurrence of a reference point in a cardiac cycle of the heart; determine a delay time based on a heart rate of the patient; and begin a next cycle of the repeating rotational speed profile at a point in time that is the delay time from the time of occurrence of the reference point in the cardiac cycle of the heart.

12 . The circulatory support system of claim 11 , wherein the delay time can be set via an input by a medical professional.

13 . The circulatory support system of claim 10 , wherein the non-transitory instructions are executable by the at least one processor to further cause the at least one processor to determine a rotational speed variation amplitude for the repeating rotational speed profile, wherein the controller uses the rotational speed variation amplitude to control operation of the ventricular assist device so that a maximum rotational speed of the repeating rotational speed profile is greater than a minimum rotational speed of the repeating rotational speed profile by the rotational speed variation amplitude.

14 . The circulatory support system of claim 13 , wherein:
the rotational speed variation amplitude is set to be equal to a first rotational speed variation amplitude at a first reference heart rate; the rotational speed variation amplitude is set to be equal to a second rotational speed variation amplitude at a second reference heart rate; the second rotational speed variation amplitude is greater than the first rotational speed variation amplitude; and the second reference heart rate is greater than the first reference heart rate.

15 . The circulatory support system of claim 10 , wherein each cycle of the repeating rotational speed profile generates a pressure pulse that is synchronized with ventricular systole of the respective cardiac cycle of the heart.

16 . The circulatory support system of claim 10 , wherein each cycle of the repeating rotational speed profile generates a pressure pulse that is synchronized with ventricular diastole of the respective cardiac cycle of the heart.

17 . The circulatory support system of claim 9 , wherein the non-transitory instructions are executable by the at least one processor to further cause the at least one processor to determine a rotational speed variation amplitude for the repeating rotational speed profile, wherein the controller uses the rotational speed variation amplitude to control operation of the ventricular assist device so that a maximum rotational speed of the repeating rotational speed profile is greater than a minimum rotational speed of the repeating rotational speed profile by the rotational speed variation amplitude.

18 . The circulatory support system of claim 17 , wherein:
the rotational speed variation amplitude is set to be equal to a first rotational speed variation amplitude at a first reference heart rate; the rotational speed variation amplitude is set to be equal to a second rotational speed variation amplitude at a second reference heart rate; the second rotational speed variation amplitude is greater than the first rotational speed variation amplitude; and the second reference heart rate is greater than the first reference heart rate.

19 . The circulatory support system of claim 1 , wherein the non-transitory instructions are executable by the at least one processor to cause the at least one processor to:
process the electrocardiogram signal to detect an arrhythmia of the heart; and output an arrhythmia alarm in response to detecting the arrhythmia of the heart.

20 . The circulatory support system of claim 1 , wherein the

Assignees

• Tc1 Llc

Inventors

• Harjes Daniel I
• Kimball Brian
• Toutam Pritika
• Qu Fujian

Classifications

• A61M60/216

  including a rotating member acting on the blood, e.g. impeller · CPC title

• A61M60/178

  drawing blood from a ventricle and returning the blood to the arterial system via a cannula external to the ventricle, e.g. left or right ventricular assist devices · CPC title

• A61M60/422

  the force acting on the blood contacting member being electromagnetic, e.g. using canned motor pumps · CPC title

• A61M60/538

  Regulation using real-time blood pump operational parameter data, e.g. motor current · CPC title

• A61M2230/63

  Motion, e.g. physical activity · CPC title