Granted Patent B2

US 12,343,517 · App. 18/216,925 · Granted Jul 1, 2025

Inventors: Alexander Medvedev (Ann Arbor, MI); Masamichi Yanai (Ann Arbor, MI)

Assignee: TC1 LLC

A61M60/232A61M60/178A61M60/515A61M60/538A61M60/148A61M2205/3334

Abstract

Claims (51)

1. A blood pump device, comprising:

a pumping chamber having an inlet for receiving blood from a ventricle of a user;

an impeller received in the pumping chamber;

a motor coupled to the impeller for driving rotation of the impeller; and

controller that is configured to:

determine a timing of a cardiac cycle of the user; and

vary a speed of the motor based on the timing of the cardiac cycle of the user such that:

a speed of the motor begins ramping down during a systolic phase of a cardiac cycle; and

the speed of the motor begins ramping up during a diastolic phase of the cardiac cycle.

2. The blood pump device of claim 1 , wherein the controller is further configured to:

measure an instantaneous phase current in at least two phases of a stator of the motor;

calculate a current corresponding to a third phase;

estimate a position and speed of the impeller based on the measured instantaneous phase currents;

generate commanded voltage output values based on the position and speed of the impeller, an average target speed of the impeller, and an instantaneous speed of the impeller;

detect the cardiac cycle from the measured instantaneous phase currents and the current corresponding to the third phase; and

input the commanded voltage output values to a pulse width modulator circuit to vary the speed of the motor.

3. The blood pump device of claim 2 , wherein the controller is further configured to:

identify a heart rate by measuring a time between current peaks.

4. The blood pump device of claim 1 , wherein:

the speed of the motor begins to ramp down at a calculated time after an occurrence of a current peak.

5. The blood pump device of claim 1 , wherein:

the speed of the motor begins to ramp up at a calculated time after a current minimum value is detected.

6. The blood pump device of claim 1 , wherein:

the motor is operable in a variable speed mode or a constant speed mode; and

selection of the variable speed mode or the constant speed mode is determined based on a physiological capability of a patient.

7. The blood pump device of claim 6 , wherein:

the variable speed mode is selected when a left ventricle of the patient is weak; and

the constant speed mode is selected when the left ventricle has recovered.

8. A method of operating a blood pump device, comprising:

determining a timing of a cardiac cycle of a user; and

varying a speed of a motor of the blood pump device based on the timing of the cardiac cycle of the user such that:

a speed of the motor begins ramping down during a systolic phase of a cardiac cycle; and

the speed of the motor begins ramping up during a diastolic phase of the cardiac cycle.

9. The method of operating a blood pump device of claim 8 , wherein:

the speed of the motor begins to ramp down at a calculated time after an occurrence of a current peak; and

the calculated time is based on a heart rate of the user.

10. The method of operating a blood pump device of claim 8 , wherein:

the speed of the motor begins to ramp up at a calculated time after a current minimum value is detected; and

the calculated time is based on a heart rate of the user.

11. The method of operating a blood pump device of claim 8 , further comprising:

receiving a signal from a pacemaker, the signal comprising information about pulse timing.

12. The method of operating a blood pump device of claim 11 , further comprising:

determining one or both of instantaneous speed and magnitude of current vector based on pulse timing; and

generating commanded voltage output values based on the one or both of instantaneous speed and magnitude of current vector; and

inputting the commanded voltage output values to a pulse width modulator circuit to vary the speed of the motor.

13. The method of operating a blood pump device of claim 8 , wherein:

the motor operates in a constant torque mode in which the speed of the motor changes inversely with a flow rate of the blood pump device.

14. The method of operating a blood pump device of claim 13 , wherein:

the motor operates at an average speed;

the average speed is determined by a physiological monitor; and

a current is adjusted to obtain a desired average speed.

Assignments (4)

Continuity (5)

References Cited (332)