CATHETER PUMP HAVING A PUMP HEAD FOR INTRODUCING INTO THE ARTERIAL VASCULATURE

Abstract

A catheter pump having a rotor shaft rotatably arranged in the inner catheter for driving an expandable conveyor element provided at the pump head. The conveyor element is rotatably mounted between a. distal hearing point and a proximal bearing point, wherein the outer catheter has a sleeve section on the distal end thereof surrounding the proximal bearing point, and wherein the proximal bearing point can be moved in the axial direction relative to the sleeve section in order to expand the conveyor element, wherein the proximal bearing point comprises a bearing receiver having a rotational bearing point for a rotary head rotationally fixed to the distal end of the rotor shaft, and a force application point at an axial distance to same for a force application section provided at the distal end of the inner catheter for axially moving the proximal bearing points relative to the sleeve section.

Claims

1. A Catheter pump having a pump head for introducing into an arterial vasculature, an outer catheter, an inner catheter arranged in the outer catheter, and a rotor shaft rotatably arranged in the inner catheter for driving an expandable conveyor element provided at the pump head, wherein the expandable conveyor element being rotatably mounted between a distal bearing point and a proximal bearing point, the outer catheter has, on the distal end thereof, a sleeve section surrounding the proximal bearing point, the proximal bearing point is movable in the axial direction relative to the sleeve section for expanding the expandable conveyor element, the proximal bearing point comprises a bearing receiver having a rotational bearing point for a rotary head rotationally fixed to the distal end of the rotor shaft, and the proximal bearing point having a force application point at an axial distance therefrom for a force application section provided at the distal end of the inner catheter for axially moving the proximal bearing points relative to the sleeve section.

2. The Catheter pump according to claim 1, wherein the bearing receiver is sleeve-shaped and the rotational bearing point is formed by a first inner groove and the force application point is formed by a second inner groove.

3. The Catheter pump according to claim 1, wherein the bearing receiver comprises at least two bearing shells.

4. The Catheter pump according to claim 3, wherein the sleeve section is formed such that, in order to mount the proximal bearing point, first the bearing shells are placed on the rotary head and on the force application section in the radial direction and then the sleeve section is pushed over the bearing shells in the axial direction.

5. The Catheter pump according to claim 4, wherein the bearing receiver has recesses in the outer side facing the sleeve section such that irrigation fluid flowing between the inner catheter and the outer catheter can flow between the bearing receiver and the inner wall of the sleeve section.

6. The Catheter pump according to claim 5, wherein a storage chamber adjoins the distal end of the bearing receiver, in which chamber irrigation fluid collects during operation and from which the irrigation fluid is conducted further to the distal bearing point, into the arterial vasculature and/or back through the inner catheter.

7. The Catheter pump according to claim 6, wherein the force application section is arranged on a bushing which is fixedly arranged on the distal end of the inner catheter.

8. The Catheter pump according to claim 7, wherein the bushing has a collar section at a distance from the force application section on the side facing away from the rotational bearing point, which collar section forms an axial stop together with a spacer sleeve.

9. The Catheter pump according to claim 8, wherein the spacer sleeve has openings extending in the radial direction for the passage of irrigation fluid.

10. The Catheter pump according to claim 1, wherein the bearing receiver comprises at least two bearing shells.

11. The Catheter pump according to claim 1, wherein the bearing receiver has recesses in the outer side facing the sleeve section such that irrigation fluid flowing between the inner catheter and the outer catheter can flow between the bearing receiver and the inner wall of the sleeve section.

12. The Catheter pump according to claim 2, wherein the bearing receiver has recesses in the outer side facing the sleeve section such that irrigation fluid flowing between the inner catheter and the outer catheter can flow between the bearing receiver and the inner wall of the sleeve section.

13. The Catheter pump according to claim 3, wherein the bearing receiver has recesses in the outer side facing the sleeve section such that irrigation fluid flowing between the inner catheter and the outer catheter can flow between the bearing receiver and the inner wall of the sleeve section.

14. The Catheter pump according to claim 1. wherein a storage chamber adjoins the distal end of the bearing receiver, in which chamber irrigation fluid collects during operation and from which the irrigation fluid is conducted further to the distal bearing point, into the arterial vasculature and/or back through the inner catheter.

15. The Catheter pump according to claim 2, wherein a storage chamber adjoins the distal end of the bearing receiver, in which chamber irrigation fluid collects during operation and from which the irrigation fluid is conducted further to the distal bearing point, into the arterial vasculature and/or back through the inner catheter.

16. The Catheter pump according to claim 3, wherein a storage chamber adjoins the distal end of the bearing receiver, in which chamber irrigation fluid collects during operation and from which the irrigation fluid is conducted further to the distal bearing point, into the arterial vasculature and/or back through the inner catheter.

17. The Catheter pump according to claim 4, wherein a storage chamber adjoins the distal end of the bearing receiver, in which chamber irrigation fluid collects during operation and from which the irrigation fluid is conducted further to the distal bearing point, into the arterial vasculature and/or back through the inner catheter.

18. The Catheter pump according to claim 1, wherein the force application section is arranged on a bushing which is fixedly arranged on the distal end of the inner catheter.

19. The Catheter pump according to claim 2, wherein the force application section is arranged on a bushing which is fixedly arranged on the distal end of the inner catheter.

20. The Catheter pump according to claim 3, wherein the force application section is arranged on a bushing which is fixedly arranged on the distal end of the inner catheter.

Description

[0016] Further details and advantageous designs of the invention can be found in the following description, on the basis of which one embodiment of the invention is explained and described in more detail.

[0017] In the drawings:

[0018] FIG. 1 is a perspective view of a pump head of a catheter pump according to the invention with a partially cut-away proximal bearing point;

[0019] FIG. 2 is a longitudinal section through the proximal bearing point shown in FIG. 1; and

[0020] FIG. 3 shows the bearing point shown in FIG. 2 before mounting.

[0021] The catheter pump 10 shown in FIG. 1 comprises a pump head 12 for introducing into the aorta or the heart of a patient. The pump 10 comprises an outer catheter 14, an inner catheter 16 and a rotor shaft 18 rotatably arranged in the inner catheter 16. A conveyor element 20 shown expanded in FIG. 1 can be driven in the form of a rotor 42 with propellers 22 by means of the rotor shaft 18. The propellers 22 are arranged between a distal bearing point 24 and a proximal bearing point 26 on the rotor 42. The conveyor element 20 or propellers 22 are surrounded by a cage 28 which provides various filaments 30. In the expanded state, which is shown in FIG. 1, the cage 28 is formed like a bulb, so that the propellers 22 can rotate freely within the cage 28. For introducing the pump head 12 into the aorta, the pump head 12 is not expanded, but is in a collapsed or folded state. In this collapsed state, the propellers 22 are close to the axis of rotation of the rotor 42, and the filaments 30 of the cage 28 are in a position parallel to the axis of rotation of the rotor 42.

[0022] As is clear from the section according to FIG. 2, the proximal bearing point 26 has a bearing receiver 32, which comprises a rotational bearing point 34 and a force application point 36. The rotational bearing point 34 and the force application point 36 are each formed in the sleeve-like bearing receiver 32 as circumferential inner grooves.

[0023] A rotary head 40, preferably a ball head, which is rotationally fixed to the distal end 38 of the rotor shaft 18, is rotatably mounted in the rotational bearing point 34. The rotor 42 comprising the propellers 22 is driven by means of the rotary head 40. The rotor shaft 18 is in turn driven in operation at its proximal end (not shown) by means of a drive.

[0024] A force application section 46 is provided in the force application point 36. The force application section 46 is formed by an annular collar, which is provided on a bushing 52 rigidly connected to the inner catheter 16. The annular collar engages positively in the force application point 36 which is formed by the bearing receiver 32 and is designed as a circumferential inner groove.

[0025] The bearing receiver 32 is in turn accommodated in a sleeve section 50 which is arranged at the distal end 48 of the outer catheter 14 and can be moved in the axial direction relative to the bearing receiver 32, and thus relative to the inner catheter 16.

[0026] By means of the described arrangement, by axially moving the outer catheter 14 relative to the inner catheter 16 and thus relative to the bearing receiver 32 that is movement-coupled with the inner catheter 16, the sleeve section 50 can be displaced from the distal position shown in FIG. 2, in which the conveyor element 20 is expanded, to the right into a proximal position, as a result of which the propellers 22 are folded and the cage 28 collapses.

[0027] In the distal position of the sleeve section 50 shown in FIG. 2, there is a storage chamber 54 adjoining the distal end of the bearing receiver 32. This storage chamber 54 results from the fact that the sleeve section 50 is displaced axially in the distal direction when the conveyor element 20 expands. In the proximal position of the sleeve section 50, that is to say in the case of a collapsed conveyor element 20, the bearing receiver 32 is located in the storage chamber 54.

[0028] As is clear from FIG. 3, the bearing receiver 32 consists of two bearing shells 56. In order to mount the proximal bearing point 26, first the two bearing shells 56 are placed on the rotary head 40 and the force application section 46 in the radial direction. Subsequently, the sleeve section 50 is pushed over the bearing shell 56 in the axial direction. This has the advantage that a mounting or securing of the bearing shells 56 can be carried out without further components or securing means. With this arrangement, the requirements for this mounting can be realized in the smallest space.

[0029] On the side facing away from the rotational bearing point 34, the bushing 52 has a collar section 68 which is at a distance from the force application section 46. The collar section 68, together with a spacer sleeve 62, can act as an axial stop, and thus limit the axial displacement path of the sleeve section 50.

[0030] As is also clear from FIG. 3, the bearing shells 56 have recesses 58 on their radially outer side in the form of channels extending in the axial direction. During operation of the catheter pump 10, irrigation fluid flowing between the inner catheter 16 and the outer catheter 14, which fluid is indicated by the arrow 60 in FIG. 2 and passes through a spacer sleeve 62, can flow between the bearing shells 56 and the inner wall of the sleeve section 50 into the storage chamber 54. The irrigation fluid, which is pumped under pressure between the inner catheter 16 and the outer catheter 14, thereby collects in the storage chamber 54, so that a large portion of the irrigation fluid in the intake does not come into contact with the rotary head 40 or the rotational bearing point 34. From the storage chamber 54, the irrigation fluid can then be transported, as indicated by the arrows 64, via corresponding openings (not shown in the drawings), to the distal bearing point 24 for supplying the bearing point 24. Another portion of the irrigation fluid can escape from the storage chamber 54 via a rotational decoupling, which is not further identified in the drawings, into the aorta. A third portion, about one third of the irrigation fluid, can flow from the storage chamber 54, as indicated by the arrows 66, through the rotational bearing point 34 for irrigation and lubrication thereof, and be removed between the inner catheter 16 and the rotor shaft 18 toward the proximal end of the outer catheter 14. In this way, both the rotary head 40 and the entire rotor shaft 18 can be supplied with sufficient irrigation and lubrication, the proportion of irrigation fluid flowing through the bearing receiver 32 not reaching the aorta of the patient.

[0031] On the side facing away from the rotational bearing point 34, the bushing 52 has a collar section 68 which is at a distance from the force application section 46. Together with the spacer sleeve 62, this can act as an axial stop. So that the irrigation fluid can be conducted unhindered between the bushing 52 and the spacer sleeve 62, the spacer sleeve 62, as shown in FIG. 1, comprises axial openings 70 which remain open even when the spacer sleeve 62 rests against the collar section 68 of the bushing 52.

[0032] Owing to the described design of the proximal bearing point 26, a simple yet reliable mounting of the bearing point 26 with the two bearing shells 56 can take place, while nevertheless ensuring an axial movement of the proximal bearing point 26 relative to the sleeve section 50 in order to expand the conveyor element 20.