DE102010011998A1 - Fluid pumping unit, particularly for medical area for use within body vessel, has fluid pump which consists of pump rotor and drive device for driving fluid pump, where drive device has fluid supply line and drive rotor driven by fluid - Google Patents

Abstract

The fluid pumping unit (4) has a fluid pump which consists of a pump rotor and a drive device for driving the fluid pump. The drive device has a fluid supply line and a drive rotor driven by a fluid. The drive rotor is connected with a shaft of the pump rotor directly or by a mechanical drive. A shaft of the drive rotor is rotatably connected with the shaft of the pump rotor.

Description

The The invention relates to a fluid pump device used in a medical Application, for example, to support the human heart activity introduced into a blood vessel and there can be operated.

Even though the invention especially for medical applications in Examples is described, it is also in non-medical Applications, for example, pumping in branched tube systems in non-medical area can be used with advantage.

In In medicine, so-called microinvasive applications are known in the recent past with little effort and low Danger potential for the patient diverse Allow intervention in the human body.

A special group of applications consists in the support the pumping action of the human heart in that Promoted blood by means of a micropump introduced into the body and so that the heart is relieved.

such For example, pumps can pump over the aorta a ventricle are introduced and operated there.

To For this purpose, such pumps can be connected to a catheter and advantageously be radially compressible, both corresponding pump rotors as well as the housing is radially reduced. In this Form can then such an arrangement, for example via the large blood vessels and the aortic arch be introduced into a ventricle. Is the pump available? Place placed, so can by means of various known facilities The pump is expanded and put into operation.

To the Drive of such pumps, for example, flexible shafts are known which pass through a catheter, at the end of each of the fluid pump is attached. To insert the catheter into the heart area Often a so-called guidewire is used in insert the catheter and transport it can. A corresponding expression of the flexible waves also allows certain bends of the catheter without the drive the pump is a problem.

Becomes such a catheter is guided around the aortic arch, so can the operating conditions of such a fluid pump device be improved by trying to find alternatives to the Shaft drive to find.

Such an alternative is for example in the WO 2008/104858 A2 described. There, a drivable by means of a fluid drive means is shown, which is traversed by a pressurized fluid and driven in rotation. By means of a magnetic coupling, the drive rotor transmits a rotational movement to a pumping rotor which delivers a fluid.

By the configuration described there, the catheter can be strongly curved be without the drive device unreliable and no fatigue of a shaft occurs their rotary operation in a highly curved shape. In addition, the Rotational resistance also independent in the first approximation from the curvature of the catheter.

Of the The present invention is based on the object, a fluid pump device of the type mentioned in relation to the drive to further optimize.

The Task is according to the invention with the features of claim 1.

Thereby the fluid pump device has a fluid pump with a pump rotor and a drive device with a drive rotor, wherein the Drive device for driving the fluid pump is used and a fluid pressure supply line and the drivable by means of a fluid drive rotor. The drive device may additionally comprise a fluid pressure source include or be associated with such.

For example the drive device can be designed as a so-called microturbine be, in the means of a fluid, in particular a liquid, a paddle wheel is driven. For this purpose, the liquid in the axial direction of the drive rotor are embedded in the microturbine or in Radial direction. The blade shape and orientation is in each case in known manner, as known from turbine technology, accordingly adapt.

at An operation in the human body is called pressurized Drive fluid for the microturbine usually a biocompatible liquid, e.g. Saline, used.

According to the Invention is the drive rotor with the shaft of the pump rotor directly or connected by means of a mechanical transmission.

This results in a particularly simple transmission of the drive movement from the drive rotor to the pump rotor, whereby higher torques can be transmitted, as in a magnetic coupling. A direct connection can be realized for example by a continuous, common wave. The problems that usually with egg ner magnetic coupling are connected, such as the increased mass and problems that can occur when tilting or other blockages of the fluid pump and the lack of flushing options because of the hermetic seclusion, are hereby avoided.

moreover can through a simple connection of the drive rotor With the wave of the pump protector costs can be saved.

Usually the drive rotor at the end of the catheter is not far from the Pump rotor removed, making the corresponding connection less expensive is.

moreover will be the same speed of drive rotor and pump rotor and even identical angular position guaranteed. With the magnetic coupling eliminated In addition, other sources of error for a possible tilting rotatable parts. Also, the generation of variable magnetic leakage flux fields prevented, for example, medical Devices in the vicinity of the fluid pump device interfere could.

moreover can under variable magnetic fields Presence of electrically conductive components induces voltages which are quite disturbing in the biological environment could.

Advantageous can rotate the shaft of the drive rotor with the shaft of the pump rotor be connected. The connection can be flexible or stiff be executed. A flexible connection has the advantage that the end of the catheter is still deformable in itself a stiff connection better guidance of the catheter when inserted into the body vessel for Episode has.

Of the Drive rotor and the pump motor can also be advantageous be mounted on a common shaft.

Advantageous is a liquid-tight between the drive rotor and the pump rotor or almost liquid-tight rotary feedthrough provided to the used in the field of microturbine drive fluid Keep away from the area of the fluid pump.

To step Over time, small amounts of the drive fluid, for example NaCl solution through the rotary feedthrough to the fluid pump side out, this is generally not harmful and prevents other hand, the entry of the body's fluids, in particular of the blood, from the fluid pump side to the drive side.

Advantageous can also be, if the rotary feedthrough in one Pressure chamber of the liquid / fluid pump opens. In this case, a back pressure is built up in the pressure chamber, the the exiting amount of the drive fluid at least reduced or limited.

The Invention further enables an advantageous embodiment, in which it is provided that the drive rotor and the pump rotor together to a maximum of four, better three, in particular two pivot bearings are stored.

The Direct connection of drive rotor and pump rotor thus allows the saving of additional pivot bearings.

The Swivel bearings can be made according to individual requirements be designed as plain bearings or bearings or as a combination of these two types of bearings.

Especially Advantageously, it can be provided that the drive rotor and the Pump rotor are mounted together on a single pivot bearing. The only pivot bearing, which both the drive rotor and the pump rotor stores, must be stiff and verkippfest trained. It can for example be formed by a wave in one Tube is guided or a hollow shaft on a bearing pin, wherein the contact surface between the shaft and tube or hollow shaft and bearing pin a certain minimum length in the order magnitude a millimeter should have. Accordingly, a Slide bearing between the drive and the pump rotor a preferred Embodiment.

It can also be advantageously provided that the rotary feedthrough is designed as a pivot bearing.

These Construction is particularly efficient as a corresponding bearing especially when it is designed as a sliding bearing or a sliding bearing, for example by providing Of labyrint seals, also fluid-tight can be performed.

A sees further advantageous embodiment of the invention before that the drive rotor and the pump rotor together exclusively in a first camp between them and in a second camp at the distal end (i.e., the end facing away from the drive rotor) Pumprotorwelle are stored.

With this embodiment, the number of necessary pivot bearing is kept low and it is a minimum distance of both the microturbine and the fluid pump realized by the bearing between them, while another pivot bearing at the distal. End of the pump rotor shaft is provided, where usually the free end the fluid pump device, when it is inserted into the body's own vessel, has a shock protection, which at the latest when inserted into a heart chamber abuts against a chamber wall and prevents the pump from approaching the heart wall. The end is designed in such a way that it causes no damage when abutting against a vessel wall or heart chamber, whereby lateral impacts on the pump rotor shaft are likewise undesirable, in particular during the pumping operation. For this reason, a pivot bearing at the distal end of the pump rotor shaft is desirable.

Advantageous may be provided within the scope of the invention that the drive rotor and the pump rotor together exclusively on a bearing pin the drive rotor on the one hand and at the distal end of the pump rotor shaft on the other hand are stored. The storage of the drive rotor can certainly also be designed differently and instead of a hollow shaft, the on a bearing pin is mounted, the drive rotor and a having a shaft mounted in a rotary bearing. authoritative is that in this case the pump rotor does not have its own pivot point has, so that a pivot bearing can be saved. The warehouse at the distal end of the pump rotor shaft is thereby advantageously maintained in order to absorb any lateral effects that might be acting there to be able to. However, this camp could also still be omitted.

A Further advantageous embodiment of the invention provides that the drive device has a fluid supply line within a catheter runs.

Thereby, that the Fiuidzuleitung runs inside the catheter, it is protected against external influences and space-saving housed. In addition, there are no problems during insertion of the fluid supply line, as this before insertion The catheter can be placed in these and shared with the catheter can be introduced.

The Fluid supply can be advantageous as micro tube within the catheter and run to the fluid pressure generating device, or within the catheter also so-called Lumen, d. H. longitudinally extending cavities provided be, for fluid supply and in particular for fluid discharge can serve. In the housing of the drive rotor can one or more drive nozzles may be provided, each one individual supply lines / lumens or a common supply line / a common Have lumens, if the distribution within the housing he follows. To drain one or more lines / lumens can also be provided, but there is also sufficient a single channel. A larger cross-section within the catheter for the supply and discharge of the drive fluid Overall, this leads to greater efficiency and at higher producible speeds or torques in the microturbine.

The Drive device is generally at the distal end of the Catheter centric arranged in this and advantageous also attached. there the catheter should also be liquid-tight at this end to be finished. On the other hand, however, the drive device can also be arranged inside the catheter, so that this over the drive device out to the fluid pump device out extends.

When special advantageous embodiment of the invention can also be provided that in the fluid pump, a pressure sensor or a speed sensor is provided for the pump, the connected to a control or regulating device of the fluid pressure source is.

through of the respective sensor can thus be generated by the fluid pump Pressure difference, as for example, a blood pressure difference, within and outside the heart chamber are detected or a absolute pressure, such as blood pressure in the aorta or in a ventricle. Depending on the difference between desired pressure and actual pressure can then be the speed of the microturbine and thus the delivery rate of the pump are controlled. The speed of the microturbine is essentially simple the pressurization of the fluid supply line or the amount of supplied Fluids when driving the microturbine or a throttle in the discharge line To influence the control can, for example, a controllable Throttle serve in the flow channel of the fluid. It may eventually either a controller or a controller to achieve the desired pressure or pressure difference of the fluid pump provided be. It is also conceivable that the pressure generated or Pressure difference dynamic, d. H. time-dependent, controlled or regulated, for example, when used as a blood pump too Take into account that the pressure in a blood vessel is timed with the heart contractions fluctuates.

• a) zur erleichterten Einführung in ein Körpergefäß, zumindest in bestimmten Bereichen der Fluideinrichtung, diese einen ersten radialen Einführungszustand einnehmen kann und
• b) zum funktionssicheren und leistungsfähigen Betrieb innerhalb des Körpers, vorzugsweise zumindest teilweise innerhalb eines Ventrikels eines Herzens, ein zweiter, gegenüber dem ersten radialen Zustand vergrößerter radialer Zustand einnehmbar ist.

A particularly advantageous embodiment provides that the fluid pump device is designed such that

• a) for facilitated introduction into a body vessel, at least in certain areas of the fluid device, this can take a first radial insertion state and
• b) for functionally reliable and efficient operation within the body, preferably at least partially within a ventricle of a heart, a second, relative to the first radial state enlarged radial state is ingestible.

Important Here is that in particular the radially larger-building Radially reduced areas during insertion can be because the human vessels have small diameters.

It come different parts of the fluid pumping device for this compressibility / expandability. this concerns on the one hand the pump rotor, which in the functional state (ie in the state, in which he actually pumps a body's own fluid) may be greater than during the introduction in the body. This will also damage the rotor as well as the adjacent body vessels reduced.

Possible but above all, it is the drive turbine (ie the drive rotor) to make foldable or deformable, so on the one hand during the introduction take a small radial state to be able to, and, to ensure higher pumping power, to assume an expanded functional state. This can (both on the drive rotor as well as on the pump rotor) due to deformable materials done or by articulated arrangements (hinged arrangements). Thus, a pump is provided, on the one hand is radially kleinbauend and on the other hand, a high pump power in Function state reached. This is especially true for hydraulic or pneumatically driven systems of great advantage, because the required drive torque at a small, the implantation diameter corresponding working diameter of the turbine would not be achieved. First by expansion of the hydraulic or pneumatic drive the larger working diameter can also required drive torque can be generated.

A further advantageous embodiment provides that drive rotor and pumping rotor for transmitting a rotational movement via a magnetic coupling can be coupled together. This is special then advantageous if that related to the drive rotor Medium (for example helium or air or water, physiological Saline or glucose solution) in terms of composition or quantity to be used only with limited body compatibility is and leakages / infection problems with the utmost security should be excluded. In addition, this is under Also, an axial separability of the drive units (i.e., drive rotor on the one hand and pump rotor on the other hand), the for example, in non-functional introductory state are meaningful, relieved. May be through the accompanying axial extension also a Radial reduction associated with the purposes of the above Execution.

in the The invention is based on an embodiment shown in a drawing and then described.

there shows

1 a longitudinal section through a blood vessel and a heart with an inserted catheter,

2 schematically a three-dimensional view of a microturbine,

3 a schematic representation of the fluid pump device according to the invention and

4 a schematic representation of the function of the fluid pump device.

The 1 shows a blood vessel 1 leading to a ventricle 2 leads and into that a catheter 3 is performed such that the end of the catheter with a fluid pumping device 4 into the heart chamber 2 protrudes.

The proximal end of the catheter 3 is through a lock from the vessel 1 out and passed through the body surface of a patient to a control device in the 1 is no longer shown.

Through inside the tubular catheter 3 running micro tubes 5 . 6 , of which more than 2 may be provided under pressure, a fluid to the distal end of the catheter 3 and then transported back from there. It also runs in the catheter 3 at least one signal line 7 receiving signals from a sensor in the region of the distal end of the catheter 3 passes.

According to the invention, at the end of the catheter 3 a fluid pump is placed, which takes blood from the ventricle 2 into the aortic arch, ie into the blood vessel 1 into promoted. For this purpose, the fluid pump device is pushed through the cavity of the aorta and inserted in the entrance to the heart chamber 2 , In this way it is possible from the ventricle 2 Suck up blood, as indicated by the arrows 8th . 9 is indicated and this by means of a Pumprotors by a pump housing 10 from where it passes through proximal openings beyond the ventricle 2 into the aorta, as indicated by the arrows 11 . 12 is indicated.

The Details of the function of the fluid pumping means will be described the following figures described in more detail.

From the 1 it becomes clear that the catheter 3 is strongly curved by its location in the aortic arch. So far, the drive to such Blood pumps use pump rotors that are driven by long flexible shafts passing through the catheter 3 to a lock and from there to the body, where the shaft can be rotated by a drive. In order to avoid the difficulties with the rotating shaft, which adjust at a high curvature, it has also been proposed to provide directly an electric motor drive in the pump head, but in turn leads to problems in cooling.

In the solution according to the invention is about micro hoses 5 . 6 a micro-turbine driven at the distal end of the catheter, which in turn drives the pump motor.

The 2 shows an example of such a microturbine with a turbine housing 13 , the axial openings 14 in which a fluid under high pressure can be injected. From these openings 14 flows out the fluid under redirection ra dial and azimuthally in the cylindrical cavity of the turbine housing 13 and drives there the drive rotor located therein 15 rotationally. This sits on a hollow shaft 16 on a bearing bolt 17 can be stored. However, it is also conceivable the wave 16 perform as a massive wave that is stored in the course of their length in one or more pivot bearings, such as sliding or rolling bearings.

The Fluid that has passed through the turbine is replaced by one or more Micro hoses back and through the catheter directed to a fluid reservoir, in the vicinity also the pressure source, such as a pressure pump is located.

When Fluid for driving the microturbine is being used in the medical field, conveniently saline (NaCl) used.

The 3 shows schematically the construction at the head of the catheter, wherein the end of the tubular catheter 1 recognizable in a section is as well as the micro hoses 5 . 6 in the turbine housing 13 end up. Inside the turbine housing 13 is the rotor 15 shown schematically, for example, on a fixed bearing pin 17 can be stored.

The cavity of the turbine housing 13 is traversed by the drive fluid. From the turbine rotor 15 goes a wave 16 on, in the course of the pump rotor 18 the liquid pump is attached. This pump rotor has one or more helical blades 19 by means of which in the course of the rotation of the Pumprotors in the housing 20 located fluid in the axial direction 21 is transported.

For this purpose, the pump housing 20 at its intake end 21 a cage-like structure 22 from supports on which the actual housing 20 opposite the wave 16 support. For this purpose, a bearing is at the distal end 23 provided on which the supports end and in which the shaft 16 is rotatably mounted.

Between the columns 22 There may be blood from the ventricle 2 sucked and into the pump housing 20 be transported in. After delivery, the blood at the downstream end passes through a similar lattice structure 24 out again and continues to flow through a discharge hose 25 who is in the field 26 liquid-tight with the pump housing 20 connected is.

In the downstream area has the outflow hose 25 openings 27 . 28 through which the blood can flow into the aorta.

It should be noted that also a variant without the outlet hose 25 is conceivable, at the pump housing 20 seals directly at the exit of the heart chamber and the blood from the downstream openings in the area of the support structure 24 from the pump housing 20 emanates into the aorta. The pump housing 20 For this purpose, it can also taper conically into a tube at the downstream end, which in turn has outflow openings and conically onto the catheter tube 1 tapers. The housing 20 For example, it can be designed as a flexible, tubular film which is tensioned in the form of a membrane by means of a frame which can be compressed and expanded in the radial direction.

By providing the all around distributed outflow openings 27 . 28 the outflow of the blood is swirled to avoid negative pressure effects.

The wave 16 is in the range between the microturbine 15 and the pump housing 20 in an execution 29 sealed so that only a small portion of the drive fluid from the interior of the turbine housing 13 to the pump housing 20 can flow.

Furthermore the pump housing has a blood overpressure in this area in operation, which ensures that the outflowing Quantity of drive fluid remains low.

The implementation 29 can also be designed as a sliding bearing or as a rolling bearing, in addition to the sealing function to provide a bearing support function.

The horizontal lines 30 . 31 . 32 . 33 represent possible positions for pivot bearings in the field of wave 16 which serve to rotatably store both the microturbine and the pump rotor as little as possible. Ideally, a single pivot bearing will suffice either in the area 30 the microturbine, for example bearing the hollow shaft of the microturbine on a bearing pin 17 , or in the field 31 in the implementation of the wave 16 or in the area 32 in which a warehouse 34 at the entrance to the pump housing 20 can be provided.

Just one of these pivot bearings can be enough to cover the entire shaft 16 to lead accordingly, it being advantageous, in each case in the case of the different variants in addition to the distal end of the camp 23 to provide for stabilization. In addition, it is not unlikely that over the spacer 35 which rested the grid construction 21 . 22 in the area of the ventricular wall should avoid lateral impacts on the shaft 16 be exercised, focusing on the pump rotor 18 continue. An error is caused by the warehouse 23 reliably avoided. Alternatively, the wave 16 also run in a hose-like wave cover, the inside possibly a bearing and on the outside Steben 21 . 22 may have to support the pump housing. Distal such a tube may be formed as a pigtail, spiral or basket-like.

The 4 shows a schematic representation of the fluid pump device according to the invention, wherein the turbine rotor 15 and the pump rotor 18 are represented as boxes moving through the shaft 16 are connected. Possible bearings are with 30 . 31 . 32 . 23 designated. In the field of microturbine is the inflow 5 and the drain 6 represented in the form of micro-tubes which extend into the catheter tube. The entire section at the end of the catheter comprising the microturbine and the fluid pump is designated by the reference numeral 36 designated.

The section between the microturbine and the located at the proximal end of the catheter controller is with 37 designated while the controller with 38 is designated.

There are also sensors 39 . 40 represented, for example, the speed of the microturbine or the pump rotor on the one hand and the pressure generated by the fluid pump or the pressure difference on the other hand and to the control unit 38 conduct.

hereby it is possible to transfer by means of the control unit the fluid pressure of the drive fluid or the amount of drive fluid or the back pressure in the outlet channel the speed of the microturbine and thus to control the pumping power or to regulate in one certain desired degree the heart and thus to support the blood circulation.

through the simple construction and connection between the microturbine and the fluid pump is a simple, reliable construction allows the very inexpensive to produce and less error prone is. Also magnetic or electromagnetic effects are avoided for example, by a magnetic coupling with fast rotating Bar magnets could arise and others, for example disrupting medical devices such as pacemakers could.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - WO 2008/104858 A2 [0009]

Claims (17)

Fluid pump device, in particular for the medical sector for use within a body vessel ( 1 ) with a fluid pump having a pumping motor ( 18 ), and a drive device for driving the fluid pump, wherein the drive device, a fluid supply line ( 5 ) and a driven by a fluid drive rotor ( 15 ), characterized in that the drive rotor ( 15 ) directly or by means of a mechanical transmission with the shaft of the pump rotor ( 18 ) connected is. Fluid pump device according to claim 1, characterized in that a shaft of the drive rotor ( 15 ) with the wave ( 16 ) of the pump protector ( 18 ) is rotatably connected. Fluid pump device according to claim 1, characterized in that the drive rotor ( 15 ) and the pump rotor ( 18 ) on a common wave ( 16 ) are attached. Fluid pump device according to claim 1, 2 or 3, characterized in that between the drive rotor ( 15 ) and the pump rotor ( 18 ) a liquid-tight rotary union ( 29 ) is provided. Fluid pump device according to claim 4, characterized in that the rotary feedthrough ( 29 ) opens into a pressure chamber of the fluid pump. Fluid pump device according to claim 1 or one of the following, characterized in that the drive rotor ( 15 ) and the pump rotor ( 18 ) together not more than four, in particular three, in particular at most two pivot bearings ( 23 . 30 . 31 . 32 ) are stored. Fluid pump device according to claim 6, characterized in that the drive rotor ( 15 ) and the pump rotor ( 18 ) are mounted together on a single pivot bearing. Fluid pump device according to claim 4, 5, 6 or 7, characterized in that the rotary feedthrough ( 29 ) is designed as a pivot bearing. Fluid pump device according to one of claims 1 to 8, characterized in that the drive rotor ( 15 ) and the pump rotor ( 18 ) together exclusively in a first warehouse ( 29 . 34 ) between them and in a second camp ( 23 ) are mounted at the distal end of the pump rotor shaft. Fluid pump device according to one of claims 1 to 8, characterized in that the drive rotor and the pump rotor together exclusively on a bearing pin ( 17 ) of the drive rotor ( 15 ) on the one hand and at the distal end of the pump rotor shaft ( 16 ) are stored on the other hand. Fluid pump device according to one of claims 1 to 10, characterized in that the drive device to a fluid supply line ( 5 ) within a catheter ( 3 ) runs. Fluid pump device according to claim 11, characterized in that the drive device at the distal end of a catheter ( 3 ) is arranged centrally in this. Fluid pump device according to claim 11 or 12, characterized in that the fluid supply line as a micro tube ( 5 ) within the catheter ( 3 ) extends to a fluid pressure generating device. Fluid pump device according to claim 11 or 12, characterized in that the fluid supply line as the cavity of the catheter ( 3 ) is formed, wherein in particular in the catheter, a second cavity is additionally provided as fluid discharge. Fluid pump device according to claim 1 or one of the following, characterized in that in the region of the fluid pump, a pressure sensor ( 39 . 40 ) and / or a speed sensor is provided, which with a control or regulating device ( 38 ) of the fluid pressure source is connected. Fluid pump device according to one of the preceding Claims, characterized in that they are so is trained that a) for easier introduction in a body vessel, at least in certain Areas of the fluid pumping device, a first radial insertion state ingestible is and b) for operation within the body, preferably at least partially within a ventricle of a heart, a second, enlarged compared to the first radial state radial state is ingestible. Fluid pump device according to one of the preceding claims, characterized in that the drive rotor ( 15 ) and pump rotor ( 18 ) are coupled to each other for transmitting a rotational movement via a magnetic coupling.