Fluid pump changeable in diameter, in particular for medical application
A fluid pump device changeable in diameter is provided. The device has a pump housing which is changeable in diameter and with a rotor which is changeable in diameter. The device has at least one delivery element for fluid, as well as a drive shaft on which the rotor is rotatably mounted. A bearing arrangement is arranged on the drive shaft or its extension, at the distal end of the drive shaft behind the rotor seen from the proximal end of the drive shaft. The bearing arrangement has struts, which elastically brace between a hub of the bearing arrangement and the pump housing.
1. An expandable intracardiac blood pump system comprising:
a drive unit;
a pump housing having an open distal inflow end, the pump housing being expandable into an expanded state and compressible into a compressed state, wherein in the compressed state the pump housing is sized for percutaneous insertion into a vascular system of a patient;
a radially compressible rotor disposed within the pump housing and having at least one compressible helical blade, the radially compressible rotor having a proximal end section, a distal end section, and a central bore extending from the proximal end section to the distal end section;
a catheter having a distal end coupled to the pump housing and a proximal end coupled to the drive unit;
a drive shaft disposed within the catheter and coupled to the radially compressible rotor, the drive shaft being configured to rotate the radially compressible rotor upon actuation by the drive unit; and
a distal bearing assembly positioned distal of the radially compressible rotor, the distal bearing assembly comprising a hub and a plurality of struts pivotably extending from the hub;
wherein the plurality of struts are configured to center radially about an axis coaxial with the drive shaft, and wherein when the plurality of struts are expanded, the plurality of struts contact a location along an interior surface of the pump housing.
2. The system of claim 1 , wherein the plurality of struts are configured to self-expand when the pump housing expands into the expanded state.
3. The system of claim 2 , wherein the plurality of struts do not rotate relative to the pump housing.
4. The system of claim 3 , wherein when the pump housing is in the expanded state, the radially compressible rotor and plurality of struts are also expanded.
5. The system of claim 4 , wherein when the pump housing is expanded to the expanded state, the plurality of struts and the radially compressible rotor expand independently of each other.
6. The system of claim 4 , wherein the plurality of struts supports an opening in a distal portion of the pump housing.
7. The system of claim 4 , wherein each strut of the plurality of struts comprises a first end section and a second end section, the first end sections being attached to the hub, and the second end sections comprise respective distal tips that extend radially away from the hub and axially away from the hub.
8. The system of claim 7 , wherein the plurality of struts and the radially compressible rotor have respective expanded outer diameters, and the expanded outer diameter of the plurality of struts at the second end section is greater than the expanded outer diameter of the radially compressible rotor.
9. The system of claim 4 , wherein the drive shaft includes a proximal end and a distal end, wherein the drive shaft extends through the central bore such that the distal end of the drive shaft is beyond the distal end section of the radially compressible rotor.
10. The system of claim 9 , wherein the plurality of struts are compressed when the pump housing is in the compressed state, and when the plurality of struts are compressed the hub and the plurality of struts are coaxial with the drive shaft.
11. The system of claim 10 , wherein when the pump housing is in the compressed state each strut of the plurality of struts is substantially parallel to the drive shaft.
12. The system of claim 11 , wherein when the pump housing is in the expanded state the hub is coaxial with the drive shaft.
13. The system of claim 10 , wherein when the pump housing is in the expanded state, the distal bearing assembly centers the drive shaft radially relative to the pump housing.
14. The system of claim 13 , wherein when the pump housing is in the expanded state each strut of the plurality of struts extends obliquely relative to the drive shaft.
15. The system of claim 14 , further comprising a knob positioned distal to the hub, the knob encapsulating the distal end of the drive shaft.
16. The system of claim 15 , wherein the knob abuts a distal face of the hub.
17. The system of claim 16 , wherein the knob is a catch.
18. The system of claim 4 , wherein the hub has a first section that extends axially in a direction distal to the plurality of struts.
19. The system of claim 18 , wherein the hub has a second section that extends axially in a direction proximal to the plurality of struts.
20. The system of claim 4 , wherein the plurality of struts expand pivotably about the hub.
21. The system of claim 20 , wherein the plurality of struts expand about the hub by way of flexibility.
22. The system of claim 4 , wherein the pump housing comprises a membrane covering a framework.
23. The system of claim 4 , wherein the distal bearing assembly and the pump housing are spaced axially apart along the drive shaft, and an axial spacing between the distal bearing assembly and the pump housing varies during expansion of the pump housing into the expanded state.
24. The system of claim 4 , wherein the distal bearing assembly comprises: a first ring and a second ring, the first ring movable with respect to the second ring; and wherein the plurality of struts are disposed between the first ring and the second ring.
25. The system of claim 24 , wherein the plurality of struts are configured to compress when the first ring is moved axially away from the second ring along an axis coaxial with the drive shaft.