Intracardiac pumping device
The invention relates to an intercardiac pump device comprising a pump ( 11 ) whose distal end ( 13 ) is connected to a cannula ( 15 ) which is provided with a suction head ( 16 ) for sucking blood. Said strainer is provided with a non-sucking extension ( 20 ) for stabilizing the position of said pump device in the heart and mechanically prolonging the cannula ( 15 ) without deteriorating hydraulic conditions. Said extension is also used in the form of a spacer in order to avoid that the suction head ( 16 ) adheres to a cardiac wall.
1. An intracardiac percutaneous blood pump comprising:
a catheter having an outer diameter and proximal and distal regions;
a cannula coupled to the distal region of the catheter and configured to extend across a heart valve, the cannula comprising an expansible suction head with a blood inlet and having an initial state with a first outer diameter and an expanded state with a second outer diameter, the second outer diameter being larger than the first outer diameter and the outer diameter of the catheter;
an impeller for pumping blood into the blood inlet; and
a flexible atraumatic projection coupled to the expansible suction head, the flexible atraumatic projection being positioned distal to the expansible suction head and being configured to space the blood inlet away from interior heart walls;
wherein the flexible atraumatic projection has a fixed outer diameter when the expansible suction head is in the initial state and retains that fixed outer diameter when the expansible suction head is in the expanded state.
2. The blood pump of claim 1 , wherein the catheter, cannula, and flexible atraumatic projection share a common longitudinal axis.
3. The blood pump of claim 2 , wherein the fixed outer diameter of the flexible atraumatic projection is smaller than the second outer diameter of the expansible suction head.
4. The blood pump of claim 3 , wherein the expansible suction head includes a plurality of flexible struts that couple the expansible suction head to the flexible atraumatic projection.
5. The blood pump of claim 4 , wherein the plurality of flexible struts are self-expandable from the initial state into the expanded state.
6. The blood pump of claim 5 , wherein the expansible suction head includes a blood outlet positioned between the distal region of the catheter and the blood inlet.
7. The blood pump of claim 5 wherein, in the expansible suction head's expanded state, the flexible struts are spaced apart from each other to form openings between the flexible struts, and wherein the openings comprise the blood inlet.
8. The blood pump of claim 7 , comprising a flexible polymer screen spanning between the plurality of flexible struts.
9. The blood pump of claim 8 wherein, in the expansible suction head's expanded state, the expanded struts and flexible polymer screen form a funnel for directing blood flow into the expansible suction head.
10. The blood pump of claim 8 , wherein the flexible struts have a first proximal end and a first distal end, with a first length extending therebetween, and the flexible polymer screen has a second proximal end and a second distal end with a second length that extends between the second proximal and distal ends, and wherein the second length is less than the first length.
11. The blood pump of claim 10 , wherein the flexible struts in the expanded state form a bulge having a proximal ascending side, a distal descending side and an apex disposed between the proximal ascending and distal descending sides, and wherein the flexible struts on the distal descending side connect to the flexible atraumatic tip.
12. The blood pump of claim 11 , wherein the flexible struts on the distal descending side connect to the flexible atraumatic projection at a cylindrical hub.
13. The blood pump of claim 11 , wherein the distal end of the polymer screen extends along the proximal ascending side of the bulge to an axial position proximal of the apex.
14. The blood pump of claim 11 , wherein the flexible polymer screen covers a proximal portion of the bulge.
15. The blood pump of claim 7 , wherein the cannula has proximal and distal regions, and wherein the expansible suction head is disposed at a distal region of the cannula, and the proximal region of the flexile cannula couples to the catheter and has an outer diameter that is substantially non-expanding.
16. The blood pump of claim 15 , wherein the blood outlet is disposed within the cannula.
17. The blood pump of claim 7 , wherein the blood outlet is positioned distal of the impeller.
18. The blood pump of claim 7 , wherein the flexible struts are flared and converge in a hub.
19. The blood pump of claim 18 , wherein the hub connects the flexible struts and the flexible atraumatic projection.
20. The blood pump of claim 19 , wherein the hub is cylindrical.