Blood pump for supporting heart function and method for producing a pump housing for a blood pump

Abstract

The invention relates to a blood pump (2) for supporting cardiac function and a method for producing a pump housing (4) of the blood pump (2). The proposed blood pump (2) comprises an implantable pump housing (4). Furthermore, the blood pump (2) comprises a fiber optic sensor (28) having an optical fiber (8). The optical fiber (8) is at least partially accommodated in a housing part (12) of the pump housing (4).

Description

Technical Field

[0001] The present invention relates to the field of medical technology and in particular to the field of implantable blood pumps for supporting cardiac function. The present invention relates to a blood pump for supporting cardiac function. The present invention also relates to a method for manufacturing a pump housing. Background Art

[0002] Blood pumps are known in the art. These blood pumps can be used when the patient's heart function needs support or replacement. The common system used is the so-called ventricular assist device (VAD). This heart pump can be implemented as, for example, a so-called left ventricular assist device (LVAD), a right ventricular assist device (RVAD) or a biventricular assist device (BiVAD). In addition to the blood pump implanted in the patient's body during operation, these systems generally include a control unit, which is arranged outside the patient's body and connected to the blood pump via a percutaneous line (drive train). The blood pump generally includes a motor, which includes a stator and a rotor, and the rotor is provided with blades. The motor of the blood pump can be driven by electricity supplied by the control unit, for example, wherein an electric current is generated in the winding of the stator, which causes the rotor including the blades to rotate in order to deliver the patient's blood. In some embodiments, a known system for supporting heart function may include a blood pressure sensor. In addition, a regulating device for adjusting the blood pump can be provided, which sets the delivery performance of the heart pump based on the blood pressure value determined by the blood pressure sensor. Related types of systems are described in, for example, the prior art EP3090767 A1 and EP3108980A1 published. Summary of the invention

[0003] An object of the present application is to provide an improved blood pump. In particular, an object of the present application is to provide a blood pump that is particularly durable and has a compact design. An object of the present application is also to provide a correspondingly advantageous method for producing a pump housing.

[0004] These objects are achieved by a blood pump as described below and by a method as described below. Other advantageous developments will be described further below.

[0005] The provided blood pump is suitable for supporting heart function. The blood pump comprises an implantable pump housing. The blood pump further comprises a fiber optic sensor comprising an optical fiber. The optical fiber is at least partially accommodated in a housing portion of the pump housing.

[0006] Since the optical fiber is contained in the housing portion of the pump housing of the blood pump, a particularly robust and compact design of the blood pump equipped with the sensor can be achieved. In a typical embodiment, the optical fiber sensor also includes a light source, a light detector and / or an evaluation unit, or is connected to or can be connected to the light source, the light detector and / or the evaluation unit. The optical fiber can be used to transmit an optical variable between the actual measurement site and the evaluation unit, and the optical variable represents the measured variable to be detected by the sensor. The light source is usually configured to couple light into the optical fiber. In some embodiments, the light source can be contained in the pump housing and / or rigidly connected to the pump housing. The light detector is usually configured to detect light leaving the optical fiber. In some embodiments, the light detector can be contained in the pump housing and / or rigidly connected to the pump housing. The evaluation unit can, for example, be contained in the pump housing and / or rigidly connected to the pump housing. The evaluation unit is usually connected to the light detector and can be configured for data processing, and for this purpose, for example, a processor and a data storage device can be included. The measurement site is usually located in the periphery of the pump housing, for example, on the outside of the pump housing or on the inside of the pump housing. Since a blood pump is provided which comprises a fiber-optic sensor with an optical fiber, the measuring site of the sensor can be established in a particularly compact manner without requiring substantial modifications to the blood pump in order to provide the sensor.

[0007] A problem which can occur with blood pumps of the known sensor type and which is avoided by the provided blood pump is an insufficient sealing between a pick-up or a transmission channel and an evaluation unit connected to the pick-up via the transmission channel. For example, with known sensor types, the transmission channel can be used to electrically or pneumatically transmit a variable representing a measured variable detected by the sensor between the actual measuring site and the evaluation unit. When the evaluation unit is accommodated in a pump housing, for example, the sealing between the transmission channel or the pick-up and the housing part of the pump housing accommodating the pick-up or the transmission channel can be achieved inadequately, for example, only by a plastic seal, since in the case of an implanted blood pump, blood in contact with the plastic seal would constitute an aggressive medium for plastic seals of ordinary type, which on the one hand would deteriorate the material of the plastic seal and on the other hand would be able to diffuse through the material, resulting in the long-term stability of the known blood pump being impaired.

[0008] Due to the provision of an optical fiber which is accommodated in a housing part of the pump housing, the use of conventional plastic seals can be dispensed with, so that a blood pump having particularly long-term stability is provided.

[0009] The present application also relates to a corresponding advantageous method for producing a pump housing for a blood pump. In the provided method, an optical fiber is provided. In addition, a first metal part is provided. The optical fiber is arranged on the first metal part. Thereafter, the optical fiber is at least partially covered with a second metal part. The optical fiber can also be embedded in these metal parts. For this purpose, ultrasonic energy can be introduced into the first metal part and / or the second metal part, however, thermal energy can also be introduced, for example. In this way, the first metal part and the second metal part can be joined. These metal parts can be made of the same material.

[0010] Furthermore, the optical fiber can be enclosed in these metal parts so that the optical fiber is at least partially embedded in the housing part formed by the first metal part and the second metal part in the circumferential direction (in particular without gaps). In some embodiments, the optical fiber material is bonded to these metal parts or the housing part. In this case, some areas of these metal parts can form a ring extending around the optical fiber. For example, a region of the housing part can form a closed ring extending around the optical fiber. In this way, the housing part and the optical fiber form a particularly reliable seal. The area of ​​the housing part surrounding the optical fiber is advantageously designed as a single piece, so that a particularly reliable seal is achieved.

[0011] The optical fiber generally comprises a light-guiding core. In some embodiments, the light-guiding core may comprise a plastic fiber, such as an acrylic fiber. However, when the light-guiding core comprises a glass fiber, it is advantageous, in particular for the above-mentioned sealing properties and the long-term stability of the blood pump, thereby avoiding or reducing the diffusion of blood into the light-guiding core.

[0012] In some embodiments, the light-conducting core of the optical fiber is clad. For example, the light-conducting core can be coated. Typically, a cladding made of metal is suitable in order to avoid the problems of the above-mentioned plastic-based materials. In addition, a particularly good seal can thus be achieved between the optical fiber and the housing part. For example, the cladding can comprise or consist of the same material as the housing part of the pump housing. Typically, the material of those parts of the housing part or the cladding that come into contact with the blood during use of the blood pump in the patient's body is biocompatible. The cladding of the optical fiber and / or the housing part, in particular the metal part, can advantageously contain titanium, in particular a titanium alloy. For example, the housing part, in particular the metal part, or the optical fiber can be made of titanium or a titanium alloy. In this way, the housing part or the cladding is biocompatible and in particular corrosion-resistant.

[0013] Typically, the end face of the fiber end of the optical fiber accommodated in the housing part of the pump housing is not completely covered by the housing part. A pickup of the fiber optic sensor connected to or formed by the fiber end is typically not completely covered by the housing part, so that the sensor is configured to be in contact with the inside of the patient's body and in particular with the patient's blood. The provided blood pump can be particularly corrosion-resistant because the fiber end is embedded in the housing part in such a way that the fiber end and the housing part form a plastic-free seal. In this way, blood penetration into the sealing part, which could occur, for example, in the case of a seal with a polymer component, is avoided.

[0014] The blood pump generally comprises a motor. The motor generally comprises a stator (e.g. comprising windings) and a rotor (e.g. comprising permanent magnets). The motor is generally at least partially and in particular completely accommodated in a pump housing. In addition, the pump housing surrounds and / or defines a flow channel for conveying blood. A rotor, which may be designed as a conveying element or connected to a conveying element, is generally arranged in the flow channel. The conveying element is generally also arranged in the flow channel. The pump housing generally comprises an inlet arranged upstream of the conveying element and an outlet arranged downstream of the conveying element. The inlet may comprise an inlet cannula. The pump housing may also comprise a chamber half. An area of ​​the chamber half may form an outlet of the pump housing. The portion of the flow channel defined by the chamber half may be substantially spiral.

[0015] Typically, the measured value measured by the optical fiber sensor is detected in the region of the end face of the optical fiber. In some embodiments, it can be arranged so that the optical fiber faces the flow channel for delivering blood with its end face and / or leads to the flow channel. In particular, it can be arranged so that the optical fiber is arranged so that the measurement site is located in the flow channel. In some embodiments, it can also be arranged so that the end face of the optical fiber is separated from the flow channel by the pickup of the sensor. However, it can also be arranged so that the end face of the optical fiber is configured to be in direct contact with the flow channel. For example, the optical fiber's light-guiding core can be configured and arranged to contact the patient's blood. The flow channel can be at least partially defined by the inner side of the housing part. When the optical fiber faces the flow channel with its end face, the blood pump may be particularly advantageous because the sensor only needs to modify the delimitation of the flow channel limited to a small area due to the relatively small size of the optical fiber compared to other sensor types. Typically, the need to modify the delimitation of the flow channel can be the result of the difference in the shape or material of the wall of the flow channel caused by the sensor. In this way, due to the use of the optical fiber, the optical fiber can have a small cross-section, especially compared with the traditional translucent window, so the blood pump can be configured to be particularly gentle to the blood. The cross section of the optical fiber may, for example, be no more than 1 mm, preferably no more than 500 μm, and particularly preferably no more than 200 μm.

[0016] In some embodiments, it can be arranged that the end face of the optical fiber is arranged in a section of the flow channel that is located upstream relative to the conveying element. For example, the optical fiber can lead into the flow channel at the upstream section, or the pickup can be arranged in this section. In this case, the measurement of blood parameters using the optical fiber sensor is particularly reliable because the blood has not yet come into contact with the conveying element at the entrance and has not yet been affected or damaged by it. The housing part in which the optical fiber is accommodated can be formed, for example, by the inlet cannula of the pump housing. In other embodiments, the optical fiber leads to the flow channel at the downstream section, or the pickup is arranged in this section. In this case, the housing part in which the optical fiber is accommodated can be formed, for example, by the chamber half of the pump housing.

[0017] In some embodiments, the blood pump may include a regulating device. The regulating device may be connected to the evaluation unit. The regulating device is typically configured for data processing and comprises, for example, a processor and a data storage device for this purpose. The regulating device may be connected to the fiber optic sensor and the motor of the blood pump. The regulating device may also be configured to set the delivery performance of the blood pump based on the measured values ​​determined by the fiber optic sensor. For example, in a method for initially supporting the heart, a blood pump may be provided and implanted, as described above or below. In addition, the delivery performance of the blood pump may be set based on the measured values ​​determined by the fiber optic sensor.

[0018] In some embodiments, it is arranged that the optical fiber sensor is a sensor for determining a blood parameter. For example, the sensor may be a blood pressure sensor. For example, the blood pressure sensor may include a Fabry-Perot cavity or a fiber Bragg grating. In particular, when the optical fiber sensor is a blood pressure sensor, the evaluation unit may be configured to determine the flow rate of the delivered blood based on the blood pressure value measured by the optical fiber sensor. The regulating device may be configured to activate a motor of the blood pump based on the determined flow value, for example, wherein the regulating device adapts the flow rate to a desired target flow rate.

[0019] In some embodiments, the fiber optic sensor may be configured to determine other blood parameters besides or in addition to blood pressure, such as hematocrit value, blood glucose level and / or blood oxygen level. Furthermore, it may be provided that the fiber optic sensor is a sensor for thrombus detection.

[0020] In some embodiments, the optical fiber sensor is configured to detect the position of the delivery element. For this purpose, the fiber end of the optical fiber can be arranged in the area of ​​the delivery element. The end face of the optical fiber can, for example, be directed to the delivery element. The evaluation unit can be configured to determine the position of the delivery element, for example, based on the detected light scattered back by the delivery element. In this way, for example, the swinging movement of the delivery element during the operation of the blood pump can be detected, based on which the evaluation unit can determine the viscosity of the blood. The regulating device can in turn be configured to activate the motor of the blood pump based on the determined blood viscosity.

[0021] It can be provided that the optical fiber faces with its end face the outside of the pump housing defined by the outside of the housing part. It can be provided, for example, that the optical fiber leads with its end face to the outside of the pump housing defined by the outside of the housing part. In particular, it can be provided that the optical fiber is arranged such that the measuring location is located outside the pump housing.

[0022] When the end face of the optical fiber is to face an internal housing part (e.g. a flow channel) or an external housing part), a subtractive manufacturing step may be provided during the manufacturing method for the pump housing for forming the end face of the optical fiber. For example, material may be removed from the metal parts and / or the optical fiber, in particular material may be ground off the metal parts and / or the optical fiber, such that the end face of the optical fiber is flush with the metal parts, for example after the optical fiber has been embedded in these metal parts. In this way, it can be achieved that the optical fiber forms a shared smooth surface together with the housing part, so that blood flowing through during use of the blood pump is not damaged or is damaged only to a lesser extent. Thus, the optical fiber sensor may comprise a common grinding surface, which comprises in a region a grinding end face of the optical fiber and a grinding surface of the pump housing, which grinding surface is aligned with the end face and extends circumferentially around the end face. For example, the shared grinding surface may form part of the delimitation of the flow channel.

[0023] In some embodiments, it can be additionally provided that the fiber optic sensor comprises a second optical fiber. These optical fibers can be arranged and configured in such a way that the fiber optic sensor is a fiber optic transmission sensor. For example, both optical fibers can lead into the flow channel. The end faces of the optical fibers usually face each other so that the light coupled into the first optical fiber is coupled into the end face of the second optical fiber after passing through the flow channel. After passing through the second optical fiber, the light can be detected by a light detector and evaluated by an evaluation unit. In this way, blood parameters such as the hematocrit value or the thrombus density or the presence of a thrombus can be inferred.

[0024] In some embodiments, the blood pump may include at least two fiber optic sensors, which may be designed as described above or below. For example, the blood pump may include a second fiber optic sensor. It may be provided that the first fiber optic sensor is configured to measure the blood pressure in a flow channel defined by the inner side of the housing part that transports the blood. The second fiber optic sensor may be configured to measure the blood pressure in the flow channel or at the outer side of the pump housing.

[0025] In the aspect that the second fiber optic sensor is configured to measure the blood pressure in the flow channel, it is particularly advantageous when one of the sensors is arranged upstream relative to the delivery element and the second of the sensors is arranged downstream relative to the delivery element. In this way, the evaluation unit can determine the flow rate of the delivered blood from the two measured blood pressure values ​​in a particularly simple manner.

[0026] When a second fiber optic sensor or another fiber optic sensor that can be designed identically to the first fiber optic sensor and / or the second fiber optic sensor is configured to determine the blood pressure on the outside of the pump housing, the blood pressure can be determined particularly accurately because the evaluation unit is configured to determine interferences with the blood pressure measurement based on the blood pressure values ​​measured on the outside of the pump housing and to correct the blood pressure values ​​determined in the flow channel based on the interference.

[0027] A particular advantage of the pump provided is that the optical fiber is embedded in the housing part and thus both diffusion of blood into the optical fiber and diffusion of blood into the interface between the housing part and the optical fiber can be avoided. In this way, the durability of the blood pump can be increased and the functional capacity of the blood pump can be ensured. To this end, it can be provided that the optical fiber is embedded in the housing part in such a way that the optical fiber and the housing part form a plastic-free seal. The optical fiber can also be welded into the housing part. In particular, it can be provided that the optical fiber is welded into the housing part by ultrasonic welding. In this way, a particularly effective seal can be ensured. In addition or as an alternative, the optical fiber can include a plastic-free light-conducting core. In particular, the light-conducting core can include glass and / or be made of glass. It can also be provided that the plastic-free part of the optical fiber, in particular the light-conducting core of the optical fiber, is in direct contact with the housing part. The optical fiber can be materially bonded to the housing part.

[0028] Features described above or below with respect to a blood pump for supporting a heart function can be applied to the method for producing a pump housing and vice versa. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Exemplary embodiments will be described below based on the accompanying drawings. In the accompanying drawings:

[0030] Figure 1 A schematic diagram of a blood pump implanted in a patient is shown;

[0031] Figure 2 A schematic diagram of a fiber optic sensor for a blood pump is shown;

[0032] Figure 3(a) to Figure 3(g) A schematic diagram showing method steps during the manufacture of a blood pump;

[0033] Figure 4(a) to Figure 4(d) shows a schematic diagram of a pump housing of a blood pump;

[0034] Figure 5 A schematic diagram of another fiber optic sensor for a blood pump is shown;

[0035] 6( a ) and 6( b ) show schematic diagrams of an optical fiber sensor of a blood pump designed as a blood pressure sensor;

[0036] Figure 7A schematic diagram showing a fiber optic sensor of a blood pump implemented as a sensor for determining the rotor position; and

[0037] 8( a ) and 8 ( b ) show schematic diagrams of a fiber optic sensor of a blood pump implemented as a sensor for detecting blood clots, hematocrit values, blood sugar levels, or blood oxygen levels. DETAILED DESCRIPTION

[0038] Figure 1 A body 1 of a patient is schematically shown in which a blood pump 2 for supporting the function of a heart 3 is implanted. The blood pump 2 comprises a motor, typically implemented as an electric motor, comprising a rotatable conveying element and housed in a pump housing 4 of the blood pump 2. The pump housing 4 is connected to a control unit 5, which can also be implanted, as schematically shown. In some embodiments, the control unit 5 can also be fully or partially housed in the implanted pump housing 4. In other embodiments, the control unit 5 is arranged outside the body. The pump housing 4 also comprises an inlet port 6, which is connected to an inlet cannula of the pump housing 4, via which blood can be drawn from the ventricle of the heart 3 and delivered to a blood vessel 8 via a cannula 7. The control unit 5 is configured to activate the motor of the blood pump 2 for conveying blood.

[0039] Figure 2 A schematic diagram of a blood pump 2 is shown. Repeating features are indicated by the same reference numerals in this and subsequent figures. The blood pump 2 comprises a fiber optic sensor, which comprises an optical fiber 8. The fiber optic sensor is configured to measure a measurement value, such as blood pressure, hematocrit value, thrombus density, blood sugar level, blood oxygen level or rotor position, at a measurement site 9. The measurement site 9 is determined by the position of an end face 10 of the optical fiber 8 or a pickup 11, which is optionally arranged on the end face 10. The optical fiber 8 or at least a portion of the optical fiber 8 is embedded in a housing part 12 (e.g., a titanium part) of the pump housing 4, so that the housing part 12 completely surrounds the optical fiber 8 in at least one area, and so that the optical fiber 8 and the housing part 12 are blood-tight and at the same time plastic-free. The end of the optical fiber 8 facing away from the end face 10 leads to a light source 13 (e.g., a light emitting diode) and a light detector 14. The light source 13 is configured to emit light and couple the light into the optical fiber 8, while the light detector 14 is configured to detect light leaving the optical fiber 8. The light source 13 and the light detector 14 are connected to an electronic evaluation unit 15, which is configured to activate the light source 13 and to read out the light detector 14. The evaluation unit 15 is configured to determine the aforementioned measured values ​​based on the light detected by the light detector 14. The evaluation unit 15 is also connected to an electronic regulating device 16. Based on the measured values ​​transmitted by the evaluation unit 15 to the regulating device 16, the regulating device 16 is able to activate a motor 17 of the blood pump 2 connected thereto, for example, the regulating device 16 adjusts the current in the stator winding.

[0040] Figure 3(a) to Figure 3(g) Schematically, different method steps during the manufacture of the blood pump 2 and the pump housing 4 are shown. Initially, a first metal piece 17 is provided, for example a biocompatible titanium or titanium alloy piece, which after manufacture will form a housing part 12 of the pump housing 4, for example a chamber half or an inlet cannula. Thereafter, a recess 18, for example a groove, is produced on the surface 19 of the metal piece 17. For example, the recess 18 can be milled. In a further step, the optical fiber 8 is inserted into the recess 18 and covered by a second metal piece 20, which is made of the same material as the first metal piece 17, as shown in FIG. 3( d ).

[0041] Thereafter, the optical fiber 8 is embedded in the metal pieces 17, 20 so that the metal pieces 17, 20 continuously surround the optical fiber 8, as shown in Figure 3 (e). In particular, after manufacturing, the optical fiber is at least partially embedded in the housing part so as to extend circumferentially. For this purpose, an ultrasonic horn (sonotrode) can be used, which introduces ultrasonic energy into the first metal piece 17 and the second metal piece 20. Due to the introduction of ultrasonic energy, the metal pieces 17, 20 are additionally bonded to each other so that they form a single-piece housing part 12. In some embodiments, the optical fiber 8 may include a light-guiding core made of a glass fiber or a glass fiber bundle, and additionally include a metal coating, in particular a metal coating made of titanium or a titanium alloy, so that a material bond is generated between the coating of the optical fiber 8 and the metal pieces 17, 10 during the embedding of the optical fiber 8.

[0042] FIG. 3( f) and FIG. 3( g) show side views of the device after embedding. A portion of the optical fiber 8 is completely embedded in the housing part 12 formed by the metal parts 17, 20, which portion is only shown by the dashed line in the figure. FIG. 3( f) corresponds to the device shown in FIG. 3( e). In a further step, the device is ground from one side in the direction of the arrow indicated by the reference numeral 21. After grinding, the optical fiber 8 and the housing part 17 form a shared ground surface 22, which can form the outer wall of the complete pump housing 4 or define a blood-conducting flow channel in the interior of the pump housing 4.

[0043] Figure 4(a) to Figure 4(d) Different views of the pump housing 4 of the blood pump 2 are shown. Fig. 4(a) shows an external perspective view of the pump housing 4. The pump housing 4 comprises an inlet cannula 23, into which blood from the heart 3 flows in the direction of the arrow indicated by reference numeral 24 during operation of the blood pump 2. In addition, the pump housing 4 comprises a chamber half 25, which forms a lower part delimiting an outlet opening 26, into which blood flows in the direction of the arrow indicated by reference numeral 27 during operation of the blood pump 2 into the cannula 7 and the blood vessel 8.

[0044] 4( b) shows a side view of the pump housing 4. Also shown in this illustration is an optical fiber sensor 28, which is designed as described above and whose measuring point is arranged on the outer side 29 of the inlet spigot 23 of the pump housing 4. The end face 10 of the optical fiber 8 or the possibly provided pickup 11 of the optical fiber sensor 28 covering the end face 10 is designed flush with the outer side 29 of the inlet spigot 23.

[0045] FIG. 4 (c) and FIG. 4 (d) each show a cross-sectional view through the pump housing 4 along the intersection line indicated by the letter C or D in FIG. 4 (b), the inner wall of the pump housing 4 forming a flow channel 30, in which a rotor 31 is accommodated. In the example shown, a rotor 31 is provided, which is designed as a radial rotor. In this case, the rotor 31 is configured to accelerate the blood flowing axially in the direction 24 via the inlet cannula 23 in the radial direction and guide it into the cannula 7 in the direction 27. However, in other embodiments, the blood pump 2 described here can also be correspondingly designed as an axial pump including an axial delivery rotor. The rotor 31 divides the flow channel 30 into a section 32 located upstream and a section 33 located downstream. The rotor 31 includes a rotor magnet 36, which is configured to cooperate with a stator winding 37 accommodated in the chamber half 25 to drive the motor 17.

[0046] According to the method described above, the optical fiber 8 of the fiber optic sensor 28 is embedded in the inlet cannula 23 of the pump housing 4. In addition, a light source 13, a light detector 14 and an evaluation unit 15 are schematically shown, which are connected to the optical fiber 8 and can be arranged, for example, outside the pump housing 4 and in particular outside the patient's body 1, or in some embodiments, the light source 13, the light detector 14 and the evaluation unit 15 can be integrated into the pump housing 4.

[0047] In addition to the described fiber optic sensor 28, the blood pump 2 also includes further fiber optic sensors 28', 28", 28'", 28"', which can be designed to correspond to the described fiber optic sensor 28. The end face 10' of the optical fiber or the pickup 11' of the sensor covering the end face 10' represented by the reference numeral 28' is arranged and oriented so that the measuring position of the sensor 28' is located in the upstream section 32 of the flow channel 30.

[0048] The sensors carrying the reference numerals 28″ and 28″′ point toward the rotor 31 and can be configured to determine the position of the rotor 31 . However, similar to all other sensors described above or below, these sensors 28″, 28″′ can also be designed as measurement sensors for measuring blood pressure, hematocrit value, thrombus density, blood sugar level or blood oxygen level. In this case, the optical fiber 8″ of one of the sensors 28″ is embedded in the inlet cannula 23, while the optical fiber 8″′ of the other sensor 28″′ is embedded in the chamber half 25.

[0049] In Figure 4(c), the position of another fiber optic sensor 28"" which can be designed similarly to the other above-mentioned sensors is indicated by a dotted line, where the precise measurement location can be identified in Figure 4(d) based on the end face 10"" or the pickup 11"" which covers the end face 10"" and can be present in a downstream section 33 of the flow channel 30.

[0050] The evaluation units of the sensors 28, 28', 28", 28'", 28"" can, for example, be separate components, as shown in Figure 4(c) based on the evaluation units 15, 15" and 15'" shown by way of example. However, some or all of the evaluation units can also be combined in a single electronic unit. As described above, the evaluation unit or these evaluation units can be connected to the regulating device 16. Specifically, when the sensors represented by reference numerals 28, 28' and 28'" are implemented as blood pressure sensors, the regulating device 16 can be configured to activate the motor 17 of the blood pump 2 based on, for example, the difference in blood pressure values ​​detected by the sensors represented by reference numerals 28' and 28"" and / or the difference in blood pressure values ​​detected by the sensors represented by reference numerals 28 and 28' or 28 and 28"".

[0051] Figure 5 A further embodiment of a fiber optic sensor 28 designed as a transmission sensor is shown. In addition to the optical fiber 8, the sensor comprises a further optical fiber 34. In the example shown, the optical fibers 8, 34 are each embedded in the housing part 12 of the pump housing 4 as described above, wherein the housing part 12 partially surrounds the blood conducting area, for example the flow channel 30.

[0052] The light source 13 is arranged such that the light emitted thereby can be coupled into the optical fiber 8. The optical fibers 8, 34 are arranged and oriented together with the end faces 10, 35 such that light leaving the end face 10 of one optical fiber 8 passes through the flow channel 30 and enters the second optical fiber 34 via the end face 35 of the second optical fiber 34. The light can then be detected by a light detector 14 connected to the other end of the second optical fiber 34. As described above, the evaluation unit 15 is connected to the light detector 14 and the light source 13.

[0053] FIG6( a) schematically shows a fiber optic sensor of a blood pump 2 for blood pressure measurement, which fiber optic sensor comprises a Fabry-Perot cavity 38. During blood pressure measurement using this sensor, the flow cell or pickup 11 comprises two partial reflectors 39, 40, which are characterized by a high reflectivity and together form an optical resonator. The reflector 40 adjacent to the measuring site 9 of the sensor is designed to be flexible, for example in the form of a diaphragm. The spectrum of this arrangement shows a narrow intensity maximum at a wavelength that meets the resonance requirements, while other spectral regions are almost completely eliminated. The spectrum irradiated on the pickup 11 by the optical fiber 8 and reflected thereby can be used by the evaluation unit 15 to infer the blood pressure.

[0054] Fig. 6(b) schematically shows a fiber optic sensor of a blood pump 2, which includes a fiber Bragg grating 41 for blood pressure measurement. The fiber Bragg grating 41 includes an optical interference filter embedded in the optical fiber 8, which is adjacent to the patient's blood during its use. Wavelengths within the filter bandwidth are reflected by the fiber Bragg grating 41. The reflected spectrum changes due to the length changes of the optical fiber 8 caused by the blood pressure, so that the evaluation unit 15 can infer the blood pressure from this spectrum.

[0055] Figure 7 A fiber optic sensor of a blood pump 2 for determining the position of a rotor 31 is shown. In particular in the case where the light reflection is a surface, a fiber optic distance measurement can be used, which provides reliable results. For example, for this purpose, an optical fiber extends between a light source 13 or a light detector 14 and a flow channel 30 in such a way that the end face 10 faces the rotor 31. The evaluation unit 15 is able to infer the distance or position of the rotor 31 from the intensity of the light reflected by the rotor 31. In some embodiments, the light source 13 and the light detector 14 can also each be equipped with an optical fiber, wherein the respective end faces of these optical fibers face the rotor 31.

[0056] 8(a) and 8(b) show schematic diagrams of a fiber optic sensor of a blood pump 2, which is implemented as a sensor for detecting thrombi, hematocrit values, blood glucose levels or blood oxygen levels. During hematocrit, blood glucose and oxygen measurement or thrombus detection, the transmitted or reflected light spectrum can be evaluated. The spectral distribution of the measured light can be compared with a reference curve, for example, in the evaluation unit 15. In this way, for example, the number of red blood cells, the oxygen saturation, the blood glucose level and / or the fibrin level can be measured, wherein the latter in turn allows conclusions to be drawn about the presence of thrombi.

[0057] Features of different embodiments which are disclosed only in the exemplary embodiment may be claimed in combination with one another and individually.

Claims

1. A blood pump (2) for supporting cardiac function, comprising an implantable pump housing (4) and a fiber optic sensor (28) comprising an optical fiber (8), characterized in that: The optical fiber (8) is at least partially accommodated in a housing part (12) of the pump housing (4), wherein the optical fiber (8) is embedded in the housing part (12) in such a way that the optical fiber (8) and the housing part (12) form a plastic-free seal.

2. The blood pump (2) according to claim 1, characterized in that The optical fiber (8) is welded into the housing part (12).

3. The blood pump (2) according to claim 2, characterized in that The optical fiber (8) is welded into the housing part (12) by ultrasonic welding.

4. The blood pump (2) according to any one of claims 1 to 3, characterized in that The optical fiber (8) comprises a plastic-free light-guiding core.

5. The blood pump (2) according to claim 4, characterized in that The plastic-free light guiding core comprises glass.

6. The blood pump (2) according to any one of claims 1 to 3, characterized in that The plastic-free parts of the optical fiber (8) are in direct contact with the housing part (12).

7. The blood pump (2) according to any one of claims 1 to 3, characterized in that The plastic-free light-guiding core of the optical fiber (8) is in direct contact with the housing part (12).

8. The blood pump (2) according to any one of claims 1 to 3, characterized in that The optical fiber (8) is materially bonded to the housing part (12).

9. The blood pump (2) according to any one of claims 1 to 3, characterized in that The optical fiber (8) is at least partially embedded in the housing part so as to extend circumferentially (12).

10. The blood pump (2) according to any one of claims 1 to 3, characterized in that The optical fiber sensor (28) is a blood pressure sensor.

11. The blood pump (2) according to any one of claims 1 to 3, characterized in that The optical fiber sensor (28) is a sensor for thrombus detection.

12. The blood pump (2) according to claim 1, characterized in that The end face (10) of the fiber end of the optical fiber (8) accommodated in the housing part (12) of the pump housing (4) is not completely covered by the housing part (12).

13. The blood pump (2) according to claim 12, characterized in that The optical fiber end is embedded in the housing part (12) in such a way that the optical fiber end and the housing part (12) form a plastic-free seal.

14. The blood pump (2) according to claim 12 or 13, characterized in that The optical fiber (8) faces with its end face (10) a flow channel (30) for conveying blood, the flow channel being at least partially defined by the inner side of the housing part (12).

15. The blood pump (2) according to claim 14, characterized in that A conveying element (31) is arranged in the flow channel (30), and the end face (10) of the optical fiber (8) is arranged at a section (32) of the flow channel (30) that is located upstream relative to the conveying element (31).

16. The blood pump (2) according to claim 14, characterized in that A conveying element (31) is arranged in the flow channel (30), and the optical fiber sensor (28) is configured to detect the position of the conveying element (31).

17. The blood pump (2) according to claim 12 or 13, characterized in that The optical fiber (8) faces with its end face (10) toward an outer side (29) of the pump housing (4) which is bounded by the outer side of the housing part (12).

18. The blood pump (2) according to any one of claims 1 to 3, characterized in that The housing portion (12) comprises or is made of titanium.

19. The blood pump (2) according to any one of claims 1 to 3, characterized in that The housing part (12) is the inlet spout (23) or the chamber half (25) of the pump housing (4).

20. The blood pump (2) according to any one of claims 1 to 3, characterized in that The optical fiber sensor (28) comprises a second optical fiber (34), the optical fiber (8) and the second optical fiber (34) being arranged and designed such that the optical fiber sensor (28) is an optical fiber transmission sensor.

21. The blood pump (2) according to any one of claims 1 to 3, characterized in that The optical fiber sensor is a second optical fiber sensor, and the blood pump further comprises a first optical fiber sensor, wherein the first optical fiber sensor is configured to measure blood pressure in a flow channel (30) for conveying blood, the flow channel (30) being defined by the inner side of the housing portion (12), and the second optical fiber sensor is configured to measure blood pressure in the flow channel (30) or on the outer side (29) of the pump housing (4).

22. A method for producing a pump housing (4) of a blood pump (2), the method comprising the following steps: - providing an optical fiber (8); - providing a first metal member (17); - arranging the optical fiber (8) on the first metal member (17); - at least partially covering the optical fiber (8) with a second metal element (20); as well as - Introducing ultrasonic energy into the first metal part (17) and / or the second metal part (20), thereby joining the first metal part (17) and the second metal part (20) and encapsulating the optical fiber (8) in the first metal part (17) and the second metal part (20), so that the optical fiber (8) is at least partially circumferentially embedded in the shell part (12) formed by the first metal part (17) and the second metal part (20), wherein the optical fiber (8) is embedded in the shell part (12) in such a way that the optical fiber (8) and the shell part (12) form a plastic-free seal.

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