Generating artificial pulse
View Patent ↗In order to produce a pulsatile blood flow pattern that includes time periods of relatively high blood flow rates and time periods of relatively low blood flow rates, the operating speed of a blood pump can be selectively controlled to produce an operating speed pattern that includes time periods of relatively high rotation speeds and periods of relatively low rotation speeds. For example, the blood pump is rotated at a first speed for a first period of time. The speed of the blood pump is then decreased from the first speed to a second speed and is operated at the second speed for a second amount of time. The speed of the blood pump is then decreased to a third speed for a third amount of time. If desired, the operating speed pattern can be repeated to continue the pulsatile blood flow pattern.
1. A method of controlling an implantable blood pump, the method comprising:
operating the implantable blood pump in an artificial pulse mode for a first period of time;
transmitting a first signal to the implantable blood pump to transition the implantable blood pump from the artificial pulse mode to a constant speed mode;
operating the implantable blood pump in the constant speed mode for a second period of time; and
transmitting a second signal to the implantable blood pump to transition the implantable blood pump from the constant speed mode to the artificial pulse mode;
operating the implantable blood pump back in the artificial pulse mode.
2. The method of claim 1 , wherein a net volume flow rate of the implantable blood pump during the artificial pulse mode matches the net volume flow rate of the implantable blood pump during the constant speed mode.
3. The method of claim 1 , further comprising receiving a user set speed for operating the implantable blood pump in the constant speed mode.
4. The method of claim 3 , wherein operating the implantable blood pump in the artificial pulse mode comprises:
(a) operating the implantable blood pump at a first speed for a first speed period;
(b) reducing the speed of the implantable blood pump from the first speed to a second speed;
(c) operating the implantable blood pump at the second speed for a second speed period;
(d) reducing the speed of the implantable blood pump from the second speed to a third speed;
(e) operating the implantable blood pump at the third speed for a third period of time; and
repeating steps (a)-(e).
5. The method of claim 4 , wherein the second speed of the artificial pulse mode is set based on the user set speed for operating the implantable blood pump in the constant speed mode.
6. The method of claim 5 , wherein the second speed of the artificial pulse mode is equivalent to the user set speed for operating the implantable blood pump in the constant speed mode.
7. The method of claim 6 , wherein the first speed, the third speed, the first period of time, and the third period of time of the artificial pulse mode are calculated to provide a volume flow rate associated with the artificial pulse mode that matches a volume flow rate associated with the constant speed mode.
8. The method of claim 1 , wherein the artificial pulse mode comprises:
(a) operating the implantable blood pump at a target pump speed for a first time period;
(b) decreasing the speed of the implantable blood pump from the target speed;
(c) after decreasing the speed of the implantable blood pump, transitioning the implantable blood pump back to the target speed by increasing the speed of the implantable blood pump to overshoot the target speed and then operating the implantable blood pump at the target speed.
9. The method of claim 1 , wherein the artificial pulse mode comprises:
operating the implantable blood pump at a first flow rate;
transitioning the implantable blood pump from the first flow rate to a second flow rate by increasing a speed of the implantable blood pump to overshoot the second flow rate and then operating the implantable blood pump at the second flow rate.
10. An implantable blood pump system, the system comprising:
an implantable blood pump configured to supplement or replace a pumping function of a heart, the implantable blood pump operable in a first pump speed pattern and a second pump speed pattern;
a controller coupled with the implantable blood pump and configured to receive a first input, and in response to receiving the first input, to transmit a signal to the implantable blood pump to transition from operating in the first pump speed pattern to operating in the second speed pattern;
wherein the first input is indicative of a low power condition of the implantable blood pump system;
wherein the second pattern is a constant speed mode.
11. The implantable blood pump system of claim 10 , wherein the second pump speed pattern has a lower power consumption rate than the first pump speed pattern.
12. The implantable blood pump system of claim 11 , wherein the first pump speed pattern provides a pulsatile operational mode.
13. The implantable blood pump system of claim 10 , wherein the controller is further configured to receive a second input, and in response to the second input, to transmit a signal to the implantable blood pump to transition from operating in the second pump speed pattern to operating in the first pump speed pattern.
14. An implantable blood pump system, the system comprising:
an implantable blood pump configured to supplement or replace a pumping function of a heart, the implantable blood pump operable in a first pump speed pattern and a second pump speed pattern;
a controller coupled with the implantable blood pump and configured to receive a first input, and in response to receiving the first input, to transmit a signal to the implantable blood pump to transition from operating in the first pump speed pattern to operating in the second speed pattern;
wherein the controller is further configured to receive a second input, and in response to the second input, to transmit a signal to the implantable blood pump to transition from operating in the second pump speed pattern to operating in the first pump speed pattern;
wherein the first pump speed pattern comprises an artificial pulse mode and the second pump speed pattern comprises a constant speed mode.
15. The implantable blood pump system of claim 14 , wherein the controller is further configured to receive a user input of a set speed for operating the implantable blood pump in the constant speed mode.
16. The implantable blood pump system of claim 12 , wherein at least one of the first pump speed pattern and the second pump speed pattern comprises a constant speed pattern.
17. The implantable blood pump system of claim 14 , wherein the artificial pulse mode comprises:
(a) operating the implantable blood pump at a target pump speed for a first time period;
(b) decreasing the speed of the implantable blood pump from the target speed;
(c) after decreasing the speed of the implantable blood pump, transitioning the implantable blood pump back to the target speed by increasing the speed of the implantable blood pump to overshoot the target speed and then operating the implantable blood pump at the target speed.
18. An implantable blood pump system, the system comprising:
an implantable blood pump configured to supplement or replace a pumping function of a heart, the implantable blood pump operable in a first pump speed pattern and a second pump speed pattern;
a controller coupled with the implantable blood pump and configured to receive a first input, and in response to receiving the first input, to transmit a signal to the implantable blood pump to transition from operating in the first pump speed pattern to operating in the second speed pattern;
wherein the controller is further configured to receive a second input, and in response to the second input, to transmit a signal to the implantable blood pump to transition from operating in the second pump speed pattern to operating in the first pump speed pattern;
wherein the first and second inputs are user commands.
19. The implantable blood pump system of claim 18 , wherein the first pump speed pattern comprises an artificial pulse mode.
20. The implantable blood pump system of claim 19 , wherein the artificial pulse mode comprises:
(a) operating the implantable blood pump at a target pump speed for a first time period;
(b) decreasing the speed of the implantable blood pump from the target speed;
(c) after decreasing the speed of the implantable blood pump, transitioning the implantable blood pump back to the target speed by increasing the speed of the implantable blood pump to overshoot the target speed and then operating the implantable blood pump at the target speed.
21. The implantable blood pump system of claim 19 , wherein the artificial pulse mode comprises:
operating the implantable blood pump at a first flow rate;
transitioning the implantable blood pump from the first flow rate to a second flow rate by increasing a speed of the implantable blood pump to overshoot the second flow rate and then operating the implantable blood pump at the second flow rate.
22. An implantable blood pump system, the system comprising:
an implantable blood pump configured to supplement or replace a pumping function of a heart, the implantable blood pump operable in a first pump speed pattern and a second pump speed pattern;
a controller coupled with the implantable blood pump and configured to receive a first input, and in response to receiving the first input, to transmit a signal to the implantable blood pump to transition from operating in the first pump speed pattern to operating in the second speed pattern;
wherein the first input is a user or clinician command;
wherein the second speed pattern is a constant speed mode.
23. The implantable blood pump system of claim 22 , wherein the first pump speed pattern comprises an artificial pulse mode.
24. The implantable blood pump system of claim 23 , wherein the artificial pulse mode comprises:
(a) operating the implantable blood pump at a target pump speed for a first time period;
(b) decreasing the speed of the implantable blood pump from the target speed;
(c) after decreasing the speed of the implantable blood pump, transitioning the implantable blood pump back to the target speed by increasing the speed of the implantable blood pump to overshoot the target speed and then operating the implantable blood pump at the target speed.
25. The implantable blood pump system of claim 23 , wherein the artificial pulse mode comprises:
operating the implantable blood pump at a first flow rate;
transitioning the implantable blood pump from the first flow rate to a second flow rate by increasing a speed of the implantable blood pump to overshoot the second flow rate and then operating the implantable blood pump at the second flow rate.