Cyclical pressure coronary assist pump
View Patent ↗An intravascular pump, which may be a left ventricle assist device, comprising a wall defining a pumping chamber, the wall support by struts, the struts attached to or part of an actuation system to move the wall from an expanded position to a contracted position and back to operated the pump, the actuation system may be electrically activated shape memory alloy struts, electroactive polymeric struts, or may be a balloon, struts attached to a slidable member or other suitable system.
1. A medical device, for use in a patient's vasculature comprising
a blood-impermeable wall defining a cavity having a lumen through the wall at a first end opposite a second end, the wall including a flexible section;
a frame attached to the wall;
an elongate member attached to the frame and extending through the cavity; and
an actuation system comprising one or more actuating members, the one or more actuating members connecting the frame to the elongate member, the actuation system configured to move the frame between an expanded position and a contracted position.
2. The medical device of claim 1 , wherein the actuation system comprises a shape memory material having a transformation temperature and means for moving the shape memory material through its transformation temperature.
3. The medical device of claim 1 , wherein the one or more actuating members comprise struts formed of a shape memory material, and wherein the struts are electrically connected to a voltage source.
4. The medical device of claim 1 , wherein the actuation system comprises an electroactive polymer.
5. The medical device of claim 1 , wherein a cross-section of the cavity at the first end is larger than a cross-section of the cavity at the second end when the frame is in the expanded position.
6. The medical device of claim 5 , wherein the cavity has a generally conical shape when the frame is in the expanded position.
7. The medical device of claim 5 , wherein the cavity has a slightly flattened conical shape when the frame is in the contracted position.
8. A medical device, for use in a patient's vasculature comprising
a blood-impermeable wall defining a cavity having a lumen through the wall at a first end opposite a second end, the wall including a flexible section;
a frame attached to the wall;
an elongate member attached to the frame and extending through the cavity; and
an actuation system comprising one or more actuating members, the one or more actuating members connecting the frame to the elongate member, the actuation system configured to move the frame between an expanded position and a contracted position;
wherein the actuation system comprises a balloon and an inflation lumen fluidly attached to the balloon.
9. A medical device, for use in a patient's vasculature comprising
a blood-impermeable wall defining a cavity having a lumen through the wall at a first end opposite a second end, the wall including a flexible section;
a frame attached to the wall;
an elongate member attached to the frame and extending through the cavity; and
an actuation system comprising one or more actuating members, the one or more actuating members connecting the frame to the elongate member, the actuation system configured to move the frame between an expanded position and a contracted position;
wherein the cavity has a volume of between 40 cc and 100 cc.
10. The medical device of claim 9 , wherein the cavity has a volume of between 60 cc and 85 cc.
11. A medical device, for use in a patient's vasculature comprising
a blood-impermeable wall defining a cavity having a lumen through the wall at a first end opposite a second end, the wall including a flexible section;
a frame attached to the wall;
an elongate member attached to the frame and extending through the cavity; and
an actuation system comprising one or more actuating members, the one or more actuating members connecting the frame to the elongate member, the actuation system configured to move the frame between an expanded position and a contracted position;
the medical device further comprising an anti-clotting agent.
12. An intravascular pump, comprising:
a flexible wall defining a pumping chamber; and
a pumping mechanism including a frame attached to the wall wherein the pumping mechanism comprises: an elongate member attached to the frame and extending through the chamber; and an actuation system comprising one or more actuating members, the one or more actuating members connecting the frame to the elongate member, the actuation system configured to move the frame between an expanded position and a contracted position.
13. The pump of claim 12 , wherein the pumping mechanism includes a central shaft and moveable struts extending between the central shaft and the frame.
14. The pump of claim 13 , wherein the pumping mechanism includes a balloon.
15. The pump of claim 13 , wherein the pumping mechanism further includes a member made from a shape memory alloy having a transformation temperature and means to move the shape memory alloy through the transformation temperature.
16. The pump of claim 15 , wherein the shape memory alloy comprises Nitinol.
17. The pump of claim 13 , wherein the pumping mechanism further includes an electroactive polymer.
18. The pump of claim 13 , further comprising a control system for controlling the pump.
19. The pump of claim 18 , wherein the control system comprises a sensor for measuring heart activity.
20. The pump of claim 18 , wherein the control system includes an interface for use with a pacemaker.