Implantable pump system, as well as a mehod for bringing a pump system to a location application

Abstract

The invention relates to an implantable pump system for delivering blood within the body of a patient, with a blood pump which delivers a fluid in an axial direction and comprises a rotatingly drivable rotor as well as a pump casing surrounding the rotor, as well as a support tube, in which the pump casing is arranged and held, wherein an annular gap is formed between the support tube and the pump casing. An almost physiological blood flow is rendered possible in this manner, by way of the combination of a flow through the pump casing on the one hand, and the annular gap on the other hand.

Claims

1. A transapically implantable pump system for delivering blood within a body of a patient, with a blood pump which delivers a fluid in an axial direction and comprises a rotatingly drivable rotor as well as a pump casing surrounding the rotor, wherein the pump casing is arranged and held in a support tube, wherein an annular gap is formed between the support tube and the pump casing.

2. The pump system according to claim 1, wherein a valve device which is arranged in the annular gap and which lets a fluid pass the annular gap in the axial direction in a first flow direction, and blocks the annular gap with respect to the opposite, second flow direction.

3. The pump system according to claim 1, wherein the support tube is configured such that it presses the cusps of the aortic valve into the aorta wall and fixes itself at this position during implantation into a body of a patient.

4. The pump system according to claim 1, wherein the support tube is expandable in the radial direction.

5. The pump system according to claim 1, wherein the support tube is configured as a stent.

6. The pump system according to claim 1, wherein the support tube is provided with holding anchors for the axial positioning.

7. The pump system according to claim 1, wherein the support tube is provided with support wires for the radial anchoring.

8. The pump system according to claim 1, wherein the support tube comprises a foldable wire mesh.

9. The pump system according to claim 1, wherein the blood pump comprises a rotor which delivers blood in the axial direction and which is rotatably mounted in the pump casing, in at least one bearing, in particular in two bearings.

10. The pump system according to claim 1, wherein the blood pump comprises a motor in the region of the support tube, in particular within the support tube.

11. The pump system according to claim 10, wherein the motor is connected to an energy source by way of a lead/conduit.

12. The pump system according to claim 11, wherein the lead/conduit extends out of the support tube in the axial direction.

13. A hollow catheter with a radially compressed support tube which is arranged therein, as well as with a blood pump which is fixed in the support tube and which comprises a rotor and a pump casing.

14. The hollow catheter of claim 13, included in a port system for implanting a blood pump system into the apex of the left ventricle of the heart, with a first catheter feed-through as well as with the hollow catheter, said hollow catheter being axially displaceable through the feed-through.

15. The hollow catheter of claim 14, included in the port system, wherein the feed-through comprises a valve which is designed such that it seals the port against blood running out, before the advance and after the retraction of the hollow catheter.

16. A method for placing a pump system at a location of application, in which first a hollow catheter with a radially compressible support tube as well as with a pump which is arranged in this and which has a rotor and a pump casing is led through a feed-through, the support tube is subsequently displaced out of the hollow catheter and radially expanded in a manner such that an annular gap arises between the support tube and the pump casing.

17. The pump system according to claim 1, wherein the pump together with support tube is designed such that said support tube is implantable in the region of the aortic valve and replaces the aortic valve.

Description

[0034] The invention is hereinafter represented by way of an exemplary embodiment in several figures, and is explained hereinafter. There is shown in

[0035] FIG. 1 schematically, a support tube with a pump arranged therein, in a three-dimensional view,

[0036] FIG. 2 a cross section through a radially compressed support pump with a pump arranged therein,

[0037] FIG. 3 a cross section of a radially expanded support tube, with a pump arranged therein,

[0038] FIG. 4 a plan view of the annular gap between a support tube and a pump, in a segmented detail,

[0039] FIG. 5 a longitudinal section through a support tube with a part of a pump and a valve device,

[0040] FIG. 6 a view of a part of a valve device in the radial direction with respect to the support tube,

[0041] FIG. 7 the arrangement of a port system in a human heart,

[0042] FIG. 8 a port system with a hollow catheter and with a pump system which is placed in the region of the aortic valve of a heart,

[0043] FIG. 9 the pump system of FIG. 8, with an expanded support tube,

[0044] FIG. 10 the pump system of FIG. 9, after retracting the hollow catheter as well as

[0045] FIG. 11 a plan view upon the support tube, as well as a valve device.

[0046] FIG. 1 in a three-dimensional view shows a blood pump 1 which comprises a pump casing 2 as well as a rotor 3, and is held in a support tube 6 in the form of a stent, by way of webs 4, 5.

[0047] The pump casing 2 is constructed in a cylindrical or rotationally symmetrical manner with respect to an axis 7 which also coincides with the middle axis of the shaft 8 of the rotor 3. The middle axis 7 moreover indicates the axial direction of the arrangement. The support tube 6 just as the pump casing 2 is constructed in a rotationally symmetrical manner and concentrically surrounds this.

[0048] The shaft 8 of the rotor 3 is fixed in the pump casing 2 by way of webs 9 within the pump casing 2. The webs 9 are arranged at a first end 10 of the pump casing 2. Further webs 12 which centrally fix a motor 13 designed as an electric motor in the pump casing are arranged at the second end 11 of the pump casing 2. The shaft of the motor 13 is connected to or is identical to the shaft 8 of the rotor 3. Alternative means for mounting and driving the rotor as well as the arrangement of inlet or outlet guide vanes are likewise included by the the subject-matter of the present property right.

[0049] The motor 13 is supplied with electrical energy by way of a lead 14 and drives the rotor 3. The rotor 3 comprises one or more delivery elements in the form of blades which deliver a fluid in the axial direction on rotation about the middle axis 7.

[0050] The rotor 3 as well as the pump casing can be radially compressible, so that they assume a smaller space on transport to the place of application, than on operation. The pump casing and the rotor however can also be designed in a rigid manner. The support tube 6 can likewise be constructed in a radially compressible manner, in particular if it is designed in the manner of a stent as a foldable wire mesh. The support tube 6 in this case can be radially compressed to such an extent that it snugly surrounds the pump casing 2, for transport.

[0051] This condition is shown in more detail in a cross-sectional representation in FIG. 2. There, the support tube 6 is represented in a radially compressed form, surrounding the pump casing 2 in a direct manner. The pump casing 2 is not radially compressed and surrounds the rotor 3 which is likewise not radially compressed.

[0052] In this condition, the pump system can be brought to the location of application in a simple manner and with little operative effort with regard to the patient. For this, it can firstly be brought into a hollow catheter, as will be explained in more detail further below, and then displaced with the hollow catheter.

[0053] FIG. 3 in cross section shows a pump system with a non-compressed support tube 6 which concentrically surrounds a pump casing 2 with a rotor 3 whilst forming an annular gap 33. Moreover, webs 4, 5 are represented, and these are foldable in a manner such that they do not prevent the radial compression of the support tube 6. The webs 4, 5 for example can consist of a spring elastic or of a limp material so that they can only be loaded in tension on fixing the pump casing 2 in the support tube 6.

[0054] A segment of the support tube 6 is represented in cross section in FIG. 4, together with a segment of the pump casing 2. A valve device comprising several flap segments 15, 16, 17 is arranged in the annular gap 33, between the support tube and the pump casing, wherein the flap segments are fastened in a hinge-like manner on one of the two parts, thus either on the support tube 6 or on the pump casing 2, and can pivot out in the axial direction, in order to release the annular gap for a fluid flow.

[0055] If the flap segments are aligned perpendicularly to the middle axis 7, they are then in tight contact with one another and completely block the annular gap.

[0056] Flap pockets, of which one is represented in FIG. 6 by way of example, can be provided between them. There, considered in the radial direction, two flap segments 17, 16 with a flap pocket 18 are represented, and this flap pocket flexibly connects the two flap segments 16, 17 to one another at least over a part of their length, in particular however also over the whole length, in the manner of a film hinge. The flap pocket 18 is represented in FIG. 4 in a dashed manner.

[0057] It is represented in FIG. 5 that in the idle position, represented by unbroken lines, the segments 17 are aligned perpendicularly to the middle axis 7 between the support tube 6 and the pump casing 2. In this position, the flap segments 17 abut an annular abutment 19 which is fastened to the pump casing 2 concentrically at the outside. Through this, the segments 17 create a resistance counter to a flow in the direction of the arrow 20. A flow is let through in the opposite direction, indicated by the arrow 21, by way of it moving the segments 17 into the deflected-out position 17, represented in a dashed manner, and thus opening the annular gap 33.

[0058] A check valve is therefore realised for the region of the annular gap 33, and this check valve permits a fluid flow, in particular a blood flow in only one flow direction, and blocks it in the opposite direction, wherein the flow in the centric part of the pump system, between the ends 10, 11 of the pump casing 2, is determined exclusively by the drive by way of the pump rotor. However, it is also conceivable to also control the flow in the region of the pump casing by way of a separate check valve.

[0059] A different embodiment of the check valve in the form of a cusp valve, as is known for aortic valve replacement, is also conceivable. Also several cusps can be applied instead of the known three cusps.

[0060] FIG. 7, as a typical application location for the pump system according to an embodiment of the invention, shows a human heart, and specifically more precisely the left ventricle 22, the left atrium 23, the ascending aorta 24 and the aortic valve region 25.

[0061] A feed-through 28 is inserted into the heart wall 17, in the region of the apex 26, opposite the aortic valve region 25. The feed-through for example can be designed as a pump branch (stub) with two flanges projecting radially outwards on both sides of the heart wall 27. The feed-through comprises a closure mechanism, so that after use, it can be closed for restoring the functioning capability of the left ventricle.

[0062] A left heart assist system in the form of the pump system according to an embodiment of the invention is to be placed in the region of the aortic valve 25.

[0063] In FIG. 8, it is shown that a hollow catheter 29 is inserted from the side of the heart which is opposite the aorta, through the feed-through 28 into the left ventricle 22 and is pushed through this, so that the distal end 29a of the hollow catheter with the compressed support tube and the blood pump is placed in the region of the aortic valve. The holding anchors 30 in this position can detach from the support tube 6 with the stepwise retraction of the hollow catheter, and anchor in the region of the aortic sinus.

[0064] Parts of the cusps of the aortic valve are pressed onto the aorta wall if the hollow catheter 29 is retracted further in the direction of the arrow 31. If the catheter completely releases the support tube 6 in FIG. 9, then this support tube can expand further radially and press the valve cusps completely onto the aorta wall and seize there.

[0065] Through this, the annular gap 33 between the support tube 6 and the pump casing 2 as described above arises. In the example shown, the pump casing 2 projects axially beyond the support tube. The pump casing can project axially beyond the support tube 6 at one side, or at both sides as in the example shown and as evident in FIG. 10. The support tube, however, can also be designed longer that the pump casing.

[0066] The length of the pump casing 2 in the case described here is significantly larger than the length of the support tube 6. If the hollow catheter 29 is retracted even further with respect to the position represented in FIG. 9 and is removed through the feed-through 29, then the energy lead/conduit 14 led from the motor of the pump rotor through the left ventricle and the feed-through 28 out of the heart and connected to an energy source remains, which energy source is either implanted within the patient's body or is positioned outside the patient's body. The feed-through 28 can be closed to such an extent that it seals the heart around the conduit 14.

[0067] Blood can be subsequently ejected through the annular gap 33 between the pump casing 2 and the support tube 6 and be transported into the aorta, according to the physiological function of the heart, wherein the check valve seals off the annular imp in the low pressure phase of the heart, as described above. The central pump which is arranged in support tube 6 moreover constantly delivers blood out of the left ventricle into the aorta by way of the rotating rotor. The output of the pump can be modulated in a rhythmic manner in accordance with the pulsating delivery output of the heart, in order to produce a physiologically normal flow pattern, or the output of this pump can also be kept constant.

[0068] With the described pump system, cannulae are neither necessary in the suction region nor in the ejection (delivery) region, so that the total surface which is wetted by the blood can be kept low. An almost physiological, pulsating formation of the blood flow in the aorta is moreover possible.

[0069] The incorporation of the pump system into the heart of a patient can be effected transapically with little operative effort, or also through a blood vessel. Perioperative risks are thus likewise minimised.