Cardiac pump with speed adapted for ventricle unloading

Patent metadata

Field	Value
Publication number	US-9713663-B2
Application number	US-201313873551-A
Country	US
Kind code	B2
Filing date	Apr 30, 2013
Priority date	Apr 30, 2013
Publication date	Jul 25, 2017
Grant date	Jul 25, 2017

Abstract

A blood pump system is implantable in a patient for ventricular support. A pumping chamber has an inlet for receiving blood from a ventricle of the patient. An impeller is received in the pumping chamber. A motor is coupled to the impeller for driving rotation of the impeller. A motor controller is provided for tracking systolic and diastolic phases of a cardiac cycle of the patient and supplying a variable voltage signal to the motor in a variable speed mode to produce a variable impeller speed linked to the cardiac cycle. The impeller speed comprises a ramping up to an elevated speed during the diastolic phase in order to reduce a load on the ventricle at the beginning of the systolic phase.

First claim

What is claimed is:

1. A blood pump system for implanting in a patient for ventricular support, comprising:
a pumping chamber having an inlet for receiving blood from a ventricle of the patient;
an impeller received in the pumping chamber;
a motor coupled to the impeller for driving rotation of the impeller; and
a motor controller for determining a time period of a systolic phase and a time period of a diastolic phase of a cardiac cycle of the patient, and supplying a variable voltage signal to the motor in a variable speed mode to produce a variable impeller speed linked to the cardiac cycle, wherein the impeller speed comprises a ramping up to an elevated speed beginning at a point in time during the determined time period of the diastolic phase, and prior to the determined time period of the systolic phase in order to reduce a load on the ventricle at the beginning of the systolic phase.

2. The pump system of claim 1 wherein the impeller speed comprises a ramping down to a reduced speed during the systolic phase to avoid collapse of the ventricle.

3. The pump system of claim 1 wherein the cardiac cycle provides a variable flow rate, and wherein the motor controller changes in the impeller speed inversely with changes in the flow rate.

4. The pump system of claim 3 wherein the variable speed mode is comprised of a constant current mode.

5. The pump system of claim 1 wherein the variable speed mode is comprised of matching impeller speed to a target speed.

6. The pump system of claim 5 wherein the target speed ramps up to the elevated speed during the diastolic phase and ramps down to a reduced speed during the systolic phase to avoid collapse of the ventricle.

7. The pump system of claim 6 wherein the ramp up of the target speed begins at a moment between about 50% to about 90% into the diastolic phase.

8. The pump system of claim 6 wherein the ramp down of the target speed begins at a moment between about 50% to about 90% of the systolic phase.

9. The pump system of claim 1 wherein the motor controller is configurable to provide the variable voltage signal to the motor in either the variable speed mode or a constant speed mode, wherein the constant speed mode maintains a substantially constant speed of the impeller over each respective cardiac cycle, and wherein a selection between the variable speed mode and the constant speed mode is determined according to a physiologic capability of the patient.

10. The pump system of claim 1 wherein the motor controller includes a current sensor, and wherein the motor controller tracks the systolic and diastolic phases in response to a waveform from the current sensor.

11. The pump system of claim 1 wherein the motor controller is adapted to communicate with a pacemaker implanted in the patient in order to track the systolic and diastolic phases.

Assignees

• Tc1 Llc

Inventors

• Medvedev Alexander
• Yanai Masamichi

Classifications

• A61M2205/3334

  Measuring or controlling the flow rate · CPC title

• A61M1/101

  Human Necessities · mapped topic

• A61M1/1005

  Human Necessities · mapped topic

• A61M1/1086 Primary

  Human Necessities · mapped topic

• A61M60/178 Primary

  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