WO2019191851A1

WO2019191851A1 - Fluid circulation support system and method

Info

Publication number: WO2019191851A1
Application number: PCT/CA2019/050421
Authority: WO
Inventors: Gabriel GEORGES; François TRUDEAU; Jade DOUCET-MARTINEAU
Original assignee: Georges Gabriel; Trudeau Francois; Doucet Martineau Jade
Priority date: 2018-04-06
Filing date: 2019-04-05
Publication date: 2019-10-10

Abstract

A system for supporting fluid circulation and deliverable to a fluid carrying conduit of a patient, the system comprising fluid pump units for pumping the fluid, each fluid pump unit having a longitudinal axis; and a docking unit comprising a docking unit body having at least two docking surfaces, each docking surface arranged to be couplable with at least a portion of at least one of the fluid pump units in an assembled configuration, wherein each docking surface faces outwardly from an elongate axis of the docking unit body, and wherein at least a portion of the docking surface conforms in shape to at least a portion of the fluid pump unit, such that when in the assembled configuration, the fluid pump units are positioned radially about the elongate axis of the docking unit, and outwardly of the at least two docking surfaces.

Description

FLUID CIRCULATION SUPPORT SYSTEM AND METHOD

FIELD OF THE DISCLOSURE

[0001] The present disclosure relates to systems for supporting fluid circulation in a patient, specifically but not exclusively to ventricular assist devices. BACKGROUND OF THE DISCLOSURE

[0002] Fluid carrying conduits in a patient, such as blood vessels or other fluid conduits near the heart, liver or kidneys, may require fluid circulation assistance in certain medical situations.

[0003] Ventricular Assist Devices (VADs) are an example of a device which can provide fluid circulation support. VADs can be at least partially implanted or delivered to the patient’s arteries, and typically comprise a single pump which helps the flow of blood.

[0004] Limitations of these types of systems and any other pump system within the human and animal body includes one or more of: hemolysis, thrombosis, invasive implantation or delivery methods, and discomfort to the patient due to components of the system being retained externally to the patient’s body. [0005] Therefore, there is a need for a fluid circulation support system and method which overcomes or reduces at least some of the above-described problems.

SUMMARY OF THE DISCLOSURE

[0006] It is an object of the present disclosure to ameliorate at least some of the inconveniences present in the prior art.

[0007] According to certain aspects and embodiments defined below and in the claims, there are provided systems and methods for fluid circulation support. In certain aspects and embodiments, the abovementioned inconveniences are ameliorated or avoided. [0008] The present technology is at least based in part on Developers’ observations and findings that providing a plurality of parallel pumps which overall provide the required flow rate can reduce the induced shear rate by each pump thereby reducing the chances of hemolysis, platelet activation, clotting factors destruction and/or thrombosis. [0009] Furthermore, by providing a system which is modular and includes a plurality of units which can be assembled in a conduit of a patient, ease of delivery is achieved for example through narrower conduits than the conduit to which the units are being delivered. Conduits include vessels such as blood vessels.

[0010] From one aspect, there is provided a system for supporting fluid circulation and deliverable to a fluid carrying conduit of a patient, the fluid circulation support system comprising: at least two fluid pump units for pumping the fluid, each fluid pump unit having a longitudinal axis; a docking unit comprising a docking unit body having at least two docking surfaces, each docking surface arranged to be couplable with at least a portion of at least one of the fluid pump units in an assembled configuration, wherein cadi docking surface faces outwardly from an elongate axis of the docking unit body, and wherein at least a portion of the docking surface conforms in shape to at least a portion of the fluid pump unit, such that when in the assembled configuration, the at least two fluid pumps are positioned radially about the elongate axis of the docking unit, and outwardly of the at least two docking surfaces. In certain embodiments, there are provided three fluid pump units. In certain embodiments* there are provided any number of fluid pump units. In certain embodiments, there are provided 4, 5, 6, 7, 8, 9 or 10 fluid pump units.

[0011] In certain embodiments, die docking unit and the at least two fluid pump units are arranged such that the longitudinal axes of the at least two fluid pump units substantially align with the elongate axis of the docking unit when in the assembled configuration. In certain embodiments, a cross-sectional shape of the docking unit resembles a“Y”, and defines a plurality of concave recesses for receiving the fluid pump units.

[0012] In certain embodiments, the docking unit and the fluid pump units are sized such that a diameter of the assembled fluid pump units and the docking unit is less titan a diameter of the conduit of the patient into which the system is deliverable. In certain embodiments, the docking unit and the fluid pump units are sized such that a diameter of the assembled fluid pump units and die docking unit about the same as a diameter of the conduit of the patient Into which the system is deliverable. In certain embodiments, the docking unit and the fluid pump units are sized such that a diameter of the assembled fluid pump units and the docking unit is more than a diameter of the conduit of the patient into which the system is deliverable. In these cases, the conduit could be stretchable to accommodate the assembled system.

[0013] In certain embodiments, the docking unit and the at least two fluid pump units are moveable between a delivery configuration In which the elongate axis of the docking unit and the longitudinal axes of the fluid pump units are substantially aligned, and the assembled configuration in which the at least two fluid pump units are positioned radially about the elongate axis of the docking unit

[0014] In certain embodiments, the system Anther comprises a delivery sheath fin housing the fluid pump unite and the docking unit in the delivery configuration, and arranged to be deliverable into the conduit of the patient, the delivery sheath being arranged to be removeable. [0015] In certain embodiments, the fluid pump unit comprises an outer casing having a first end and a second end, the outer casing having openings defined in the outer casing to act as a fluid inlet and a fluid outlet in use, and a motor housed in the outer casing. In certain embodiments, the motor comprises a shaft and an impeller rotatably moveable about the shaft

[0016] In certain other embodiments, the fluid pump unit comprises an outer casing having a first end and a second end, the outer casing having openings defined in the outer casing to act as a fluid Inlet and a fluid outlet in use, and an impeller. In these embodiments, a motor is positioned outside of the vessel in use. Rotation of the impeller could be powered by a flexible drive shaft, in these cases.

[0017] In certain embodiments, there is provided a barrier in the fluid puny unit, to obstruct the flow between the fluid inlet and the fluid outlet. This barrier may limit flow circulation around the assembled device so that the fluid path of least resistance is through the pumping unite input and output The barrier may completely or partially block a cross-sectional view of the conduit in which the device is implanted. The barrier may be made of any material which is biocompatible, such as polymers, metals, ceramics as well as organic-derived materials. The barrier may be incorporated into the docking device or the fluid pump units, or may be independently secured inside the vessel though its own anchoring system.

[0018] In certain embodiments, the openings comprise one opening defined at the first end of the outer casing, and at least one other opening defined circumferentially in the outer casing. In certain embodiments, the at least one other opening defined circumferentially in the outer casing stops short of extending around the entire circumference of the outer caring. In certain other embodiments, the at least one other opening defined circumferentially in the outer casing extends all the way around the circumference of the outer casing.

[0019] In certain embodiments, the system further comprises a contact portion, circumferentially aligned, and between the at least one other opening defined circumferentially in the outer casing, which contact portion feces the docking surface when the fluid pump unit and the docking unit are in the assembled configuration.

[0020] In certain embodiments, the outer casing comprises a convex and asymmetrically shaped second end, and the docking surface has a docking end having a complementary shape to the second end for receiving the second end therein.

[0021] In certain embodiments, the docking unit comprises a docking device lumen extending longitudinally through the docking unit body, and optionally a guide wire extending through the docking device lumen. The docking unit body may be made of a biocompatible materials, such as a polymer or a titanium alloy. The docking unit body can be of solid construction. A diameter of the docking unit body is about 10 mm or less, in certain embodiments.

[0022] In certain embodiments, the system farther comprises a retaining device for retaining the at least two fluid pump units and the docking unit in the assembled configuration.

[0023] In certain embodiments, the retaining device comprises a retaining ring extending around the docking surface, and optionally having a proximal end connected to the docking unit body and a distal end extending outwardly from the docking unit body. The retaining ring may be resiliently biased away from the docking surface. Alternatively, the retaining ring may be made of a shape memory alloy arranged to take up an expanded configuration when delivered in vivo, to secure the fluid pump unlb and the docking unit in the conduit The retaining device may comprise any type of arrangement which can hold the assembled device in position in the conduit

[0024] In certain embodiments, the system fiirther comprises a functional unit, also couplable with the docking unit, the functional unit bring operable to perform any one or mote of the following functions: fluid injection or drawing fluid, drug delivery, physiological sensing (temperature, pH, fluid flow). The functional unit may include a functional unit cable extending from an end of the functional unit and receivable through the docking end of the docking unit The functional unit cable may be housed in the cable housing. [0025] In certain embodiments, the system Anther comprises a power source for providing power to the fluid pump units, and/or the functional unit. The power source may comprise an induction coil electrically connected to the fluid pump units, and/or the functional unit, operably couplable to an external induction coil and a battery. In certain other embodiments, the power source comprises a battery, or any other power source. In certain embodiments, there is provided a percutaneous power source.

[0026] In certain embodiments, the external induction coil and the battery can be implemented as a wearable device. In certain embodiments, the wearable device includes at least one sensor for measuring a physiological parameter of the patient, selected as one or more of: a pulse, a saturation rate, a blood pressure, true blood flow rate, inferred blood flow rate. There may be provided additional sensors for measuring additional physiological parameters.

[0027] In certain embodiments, the wearable device Anther comprises a processor operatively communicable with the battery and optionally die sensors.

[0028] In certain embodiments, the system Anther comprises a docking mechanism for controlling relative movement between the docking unit and the at least two fluid pump units, the docking mechanism arranged to move the at least two fluid pump units between a delivery configuration in which the elongate axis of the docking unit and the longitudinal axes of the fluid pump units are aligned, and the assembled configuration in which the at least two fluid pump units are positioned radially about the elongate axis of the docking unit [0029] In certain embodiments, foe docking mechanism, comprises a cable connected to each fluid pump unit and optionally operably connectable to a cable management system for manipulating the cable to effect relative movement between each one of the fluid pump units and foe docking unit [0030] In certain embodiments, the cable extends from the outer casing of the fluid pump unit and through the docking end of the docking unit In certain embedments, the cable extends from a position at the second end of the outer casing of the fluid pump unit which is off-centre relative to a circumference of the outer casing.

[0031] In certain embodiments, the system flirther comprises a cable housing, extending beyond the docking end of the docking unit, for housing the cables of each fluid pump unit In certain embodiments, the system further comprises a sealing mechanism for operatively sealing a lumen of the cable housing from fluid infiltration. In certain embodiments, foe system further comprises a guide wire extending through the cable housing and docking unit body. A support structure, defining at least one pathway for the cables, may be provided in the cable housing lumen. The support structure may provide a plurality of pathways, one for each component in the cable lumen. This can help to avoid entanglement of foe individual components within the cable housing lumen, and improve responsiveness when handling cables housed therein, in certain embodiments. The lumen of tile cable housing can also house foe cable of the functional unit, when the functional unit is present [0032] In certain embodiments, each cable comprises an outer sheath housing at least one electrical wire, and optionally a reinforcement wire.

[0033] In certain embodiments, the system flirther comprises a cable management system, operatively connected to the cable of each fluid pump unit and arranged to be retained outside of foe patient for manipulation by a practitioner to manipulate the cables of each fluid pump unit

[0034] In certain embodiments, the system further comprises an anchoring system for releasably retaining the docking unit in the conduit of the patient In certain embodiments, the anchoring system comprises an anchor member. which is resiliently biased away from the elongate axis of the docking unit In certain embodiments, the anchor member comprises a ring connected to the docking unit, and having an arm portion which extends outwardly away from the docking unit In certain embodiments, the anchoring system comprises an expandable member. The expandable member may be configured to expend when implanted, or when deployed through other means. In certain embodiments, the anchor member comprises a stent- like structure, or an expandable scaffold. In certain embodiments, the anchoring system is associated with one or more of the cable housing, the docking unit, or the fluid pump units.

[0035] From another aspect there is provided a fluid pump unit comprising an outer casing having a first end and a second end, the outer casing having at least two openings defined in the outer casing to act as a fluid inlet and a fluid outlet, respectively, in use, and a motor housed in the outer casing. In certain embodiments, the motor comprises a shaft and an impeller rotatably moveable about the shaft, and optionally the motor including a motor casing. In certain embodiments, the motor casing is the outer casing.

[0036] From a further aspect there is provided a fluid pump unit comprising an outer caring having a first end and a second end, the outer casing having at least two openings defined hi the outer casing to act as a fluid inlet and a fluid outlet, respectively, In use, and an impeller housed in tiie outer casing. In certain embodiments, there is provided a motor housed externally to the outer caring, and electrically connected thereto, such as a flexible shaft.

[0037] In certain embodiments, the openings comprise one opening defined at the first aid of the outer casing, and at least one other opening defined circumferentially In the outer casing. In certain embodiments, the at least one other opening defined circumferentially in the outer casing stops Short of extending around the entire circumference of the outer casing. In certain other embodiments, the circumferentially defined openings extend around the entire circumference of the outer casing.

[0038] In certain embodiments, the fluid pump unit further comprises a contact portion, circumferentially aligned, and between the at least one other opening defined circumferentially in the outer casing, which contact portion feces a docking surface of a docking unit when the fluid pump unit and the docking unit are in an assembled configuration. In certain embodiments, the outer casing comprises a convex and asymmetrically shaped second end. [0039] In certain embodiments, the fluid pump unit farther comprises a cable extending from the second end, and from a position which is off-centre relative to a circumference of the second end.

[0040] In certain embodiments, the cable comprising an outer sheath defining a lumen, the lumen housing a reinforcement wire and electrical wires In electrical contact with the motor.

[0041] From another aspect, there is provided a docking unit for a fluid circulation support system, the docking unit comprising a docking unit body having at least two docking surfaces, each docking surface arranged to be couplab!e with at least a portion of at least one fluid pump unit in an assembled configuration, wherein each docking surface feces outwardly from an elongate axis of the docking unit body.

[0042] In certain embodiments, the docking unit body further comprising a docking end having an opening for receiving a cable of the fluid pump unit therethrough. In certain embodiments, the docking unit farther comprises a cable housing, extending beyond the docking end of the docking unit, for housing the cables of each fluid pump unit In certain embodiments, the cable housing further comprises a seating mechanism for operatively sealing a lumen of the cable housing from fluid infiltration, In certain embodiments, the docking unit further comprises a guide wire extending through the docking unit body, and optionally through the cable housing. A support structure, defining pathways for the cables, may be provided in the cable housing lumen. The support structure can help to avoid entanglement of the individual components within the cable housing lumen, and improve responsiveness when handling cables housed therein, in certain embodiments.

[0043] In certain embodiments, the diameter of the device (fluid pump units and docking unit) of the system in the assembled configuration is less than an internal diameter of the conduit, such as tfte aorta, in which the system will function. This can enable blood flow around and through the device, which in certain embodiments permits entrainment flow.

[0044] In certain embodiments, the diameter of the device (fluid pump units and docking unit) of the system in the assembled configuration is more than an internal diameter of the conduit, such as the aorta, in which the system will function. In these cases, the conduit will stretch to accommodate the assembled device.

[0045] From another aspect, there is provided a system 6» supporting fluid circulation, the system comprising combinations of any of the embodiments of the docking unit and the fluid pump units as described above. In certain embodiments, the system comprises a single docking unit and a single fluid pump unit In certain embodiments, the system comprises the docking mechanism. In certain embodiments, the system fiirther comprises the power source. [0046] From another aspect, there is provided a system for supporting fluid circulation and deliverable to a fluid carrying conduit of a patient which does not include a docking unit In this aspect, the fluid circulation support system comprises: at least two fluid pump units for pumping the fluid, each fluid pump unit having an outer casing and a longitudinal axis; the fluid pump units arranged to be assembled in an assembled configuration where the at least two fluid pumps are positioned such that their longitudinal axes are substantially parallel to one another; and a connecting mechanism for securing the fluid pump units in the assembled position. In certain embodiments, there are provided three fluid pump units. Any number of fluid pump units can be provided such as 2, 4, 5, 6, 7, 8, 9 or 10. In certain embodiments, the connecting mechanism comprises connecting elements acting between the coupling surfaces of the fluid pump units. In certain embodiments, the connecting elements comprise magnets, clips, and the like.

[0047] in certain embodiments, the at least two fluid pump units are moveable between a delivery configuration in which the longitudinal axes of the fluid pump units are substantially aligned, and the assembled configuration in which the longitudinal axes of the at least two fluid pump units are substantially parallel.

[0048] In certain embodiments, the system comprises a docking mechanism for moving the fluid pump units between the delivery configuration and the assembly configuration. In certain embodiments, the docking mechanism comprises a cable connected to each fluid pump unit and optionally operably connectable to a cable management system for manipulating the cable to effect relative movement between each one of the fluid pump units. [0049] In certain embodiments, the system further comprises an anchoring system for releasably retaining the fluid pump units in the assembled configuration in the conduit of the patient. In certain embodiments, the anchoring system comprises an anchor member which is resiliently biased away from the longitudinal axis of the fluid pump unit In certain embodiments, the anchor member comprises a ring connected to the fluid pump unit, and having a portion which extends outwardly away from the docking unit.

[0050] In certain embodiments, the system further comprises a delivery sheath for housing die at least two fluid pump units in the delivery configuration, and arranged to be deliverable into die conduit of the patient, the delivery sheath being arranged to be removeable.

[0051] In certain embodiments of any of die above aspects there may be provided a plurality of systems, or a plurality of fluid pump unit and docking unit devices for delivery to different or the same parts of the patient, e.g. vein, artery, two devices in series in the artery, two devices in series in the veins, one device deliverable from the subclavian artery and another device from the femoral artery.

[0052] In certain embodiments of any of the abovementioned aspects and embodiments, the diameter of die device in the delivery configuration (i.e. when the fluid pump units and optionally the docking unit are aligned in series) is leas than a diameter of the device in the assembled configuration (i.e. when the fluid pump units and optionally the docking unit are aligned in parallel). This can enable delivery of at least tile fluid pump units and the docking unit through a narrower conduit compared to a diameter of the conduit in which die fluid pump units and the docking unit will be housed. In some embodiments, the conduit is the aorta and the narrower conduit through which the device is delivered is the femoral artery or the subclavian artery.

[0053] Certain embodiments of the system are arranged, through varying the diameter and size of the various units, to provide different extents of conduit obstruction when in the assembled configuration in the conduit. In certain embodiments, when in the assembled configuration, the assembled device (one or more of the fluid pump units and the docking unit) extends substantially across the conduit diameter, permitting fluid flow through one or more units of the system. In certain other embodiments, when in the assembled configuration, the assembled device allows for fluid flow around the assembled device, as well as optionally through the device. This can lead to entrainment flow mechanics. An advantage of entrainment flow mechanics is that flow generation is enhanced or provided while preserving flow circulation around the device in case of device malfunction.

[0054] A prior art system (US 2017/0173242 Al) with a modular construction is described as having an expandable scaffold implantable into a vessel, and minipumps operably coupled to the scaffold. Unlike embodiments of the present technology, embodiments of the system of the prior art limit blood flow around the minipumps possibly increasing the risk of occlusion of the blood vessel where the device is Implanted and high thrombogenicity, as well as the inability to disassemble the device for removal. Furthermore, assembly of the minipumps into the scaffold is cumbersome and involves a number of steps.

[0055] Depending on the type of fluid flow through the conduit with the system in position in vivo, there may be provided increased pump efficiency and decreased turbulence and recirculation around the fluid pump units and the docking unit. Generally, the smaller the assembled device compered to the total conduit diameter, the more flow recirculation there will be around the device.

[0056] In certain embodiments, the system can be used to supplement weakened blood pumping function of the heart by being delivered to the aorta. Embodiments of the system can be used for the pumping of fluid for other health issues (c.g. pulling blood from the subhepatic vein of patients with cirrhosis to decrease portal hypertension) or pumping of other liquid (ascites) is not excluded from the scope of the invention, The device is of modular construct, comprising, for example of three or four separate tubular fluid pump units each delivered individually, percutaneously and in a successive sequential fashion. These fluid pump units are assembled together via coupling means as they reach their desired location inside the aorta. Definitions:

[0057] It must be noted that, as used in this specification and the appended claims, the singular form "a",“an” and“the" include plural referents unless the context dearly dictates otherwise. [0058] As used herein, the term " about" in the context of a given value or range refers to a value or range that is within 20%, preferably within 10%, and more preferably within 5% of the given value or range.

[0059] As used herein, the term "and/or” is to be taken as specific disclosure of each of the two specified features or components wife or without fee other. For example“A and/or B" is to be taken as spedfic dlsdosure of each of CO A, (ii) B and (iii) A and B, just as if each is set out individually herein.

BRIEF DESCRIPTION OF DRAWINGS

[0060] Further aspects and advantages of the present invention will become better understood with reference to the description in association with the following in which:

[0061] FIG. 1 illustrates a side view of a system comprising a docking unit and fluid pump units when in a delivery configuration, according to certain embodiments of fee present technology;

[0062] FIO. 2 illustrates a side view of the system of FIG. 1 when in an assembled configuration, according to certain embodiments of the present technology;

[0063] FIG. 3 is an exploded view of the docking unit of FIGS. 1 and 2, according to certain embodiments of the present technology,

[0064] FIG. 4 is a perspective view of the docking unit of FIG. 3 with certain components removed, according to certain embodiments of the present technology; [0065] FIG. 5 is a view from one end of the docking unit of FIG. 3 towards a docking end of the docking unit, according to certain embodiments of the present technology;

[0066] FIG. 6 is an exploded view of one of the fluid pump units of FIGS. 1 and 2, according to certain embodiments of the present technology,

[0067] FIG. 7 is a perspective view of the fluid pump unit of FIG. 6 from a second end, according to certain embodiments of the present technology; [0068] FIG. 8 is a perspective view of the fluid pump unit of FIG. 6 from a first end, according to certain embodiments of the present technology;

[0069] FIG. 9 is a perspective view of the fluid pump unit of FIG. 8 when assembled with the docking unit of FIG. 4, according to certain embodiments of the present technology;

[0070] FIG. 10 is an end view of the fluid pump units and die docking device of FIG. 2 in the assembled configuration, according to certain embodiments of the present technology,

[0071] FIG. 11 is a cross-sectional view through one cable associated with the fluid pump unit of the system, according to certain embodiments of the present technology;

[0072] FIGS. 12A and 12B are illustrations of an external charger and an internal charger of an induction charging system, respectively, for providing power to the system of embodiments of the present technology,

[0073] FIG. 13 is a perspective exploded view of another embodiment of the system comprising a docking unit and fluid pump units when in an assembled configuration, according to certain embodiments of the present technology; [0074] FIG. 14 is the system of FIG. 13 wheat installed in the aorta of a heart of a patient; and [0075] FIG. 15 is a perspective view of yet another embodiment of the system comprising a docking unit and fluid pump unite in an assembled configuration; according to certain embodiments of the present technology. DETAILED DESCRIPTION

[0076] The present disclosure is not limited in its application to the details of construction and tiie arrangement of components set forth in the following description or illustrated in the drawings. The disclosure is capable of other embodiments and of being practiced or of being carried out in various ways. Also, the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of "including", "comprising¹¹, or "having", "containing", "involving" and variations thereof herein, is meant to encompass the items listed thereafter as well as, optionally, additional items. In the following description, the same numerical references refer to similar elements.

[0077] Broadly, there is provided a system 10 for fluid circulation support which is at least in part deliverable to a fluid carrying conduit 12 (FIG. 14) of a patient The system 10 is arranged to provide fluid circulation support by pumping of the fluid in the conduit 12 of the patient In certain embodiments, the fluid circulation support system 10 to arranged to augment the patient's existing fluid circulation. In certain other embodiments, the fluid circulation support is arranged to deliver the fluid circulation. Certain embodiments of the system 10 will be described below to relation to the aorta as the fluid conduit 12 of the patient, and blood as the fluid. However, embodiments of the present technology are equally applicable to other conduits 12 and other fluids in the human and animal body, such as vascular conduits in the liver, and the ureter in the kidney, and the like.

[0078] Referring to FIGS. 1 and 2, the fluid circulation support system 10 is modular and comprises a plurality of fluid pump units 14 and a docking unit 16. The system 10 can be arranged in a delivery configuration (FIG. 1) for delivery to the patient, and in an assembled configuration (FIG. 2) for in vivo functioning of the system 10. The system 10 can be reconfigured between the delivery configuration and the assembled configuration, in vivo. In other words, a device portion 18 (FIG. 10) of the system 10 comprising the fluid pump units 14 and the docking unit 16 can be assembled and dis-assembled, whilst in tiie conduit 12 of the patient Advantageously, hi certain embodiments, this means that the system 10 can be delivered to the patient and removed in a slimmer configuration to minimize the invasiveness of the procedure, and hence discomfort, to the patient. The assembly in vivo, can enable the system 10, to maximise its functional performance in use. The inclusion of more than one fluid pump unit 14 can mean that each fluid pump unit 14 exerts a lower shear stress on the fluid, without compromising tiie flow rate. When the fluid is blood, this can reduce or avoid damage to blood components, such as hemolysis in certain embodiments.

[0079] In the delivery configuration, the fluid pump units 14 and the docking unit 16 are aligned in series, and can be housed in a delivery sheath 20 (FIG. 1) before and during delivery. The alignment of the fluid pump units 14 and the docking unit 16 can present a minimal diameter of tiie system 10 which can ease the delivery into the aorta of the patient through a narrower ^' conduit 12, such as the subclavian artery, In the assembled configuration, the fluid pump units 14 and tiie docking unit 16 are aligned in parallel, representing a larger overall diameter of the system 10.

[0080] Turning now to the docking unit 16 (FIGS. 3-5), the docking unit 16 comprises a docking unit body 22 having a plurality of docking surfaces 24. Bach docking surface 24 is arranged to be couplable, at least in part, with a portion of at least one of the fluid pump units 14, when in the i

assembled configuration. Each docking surface 24 is arranged to conform in shape to a part of an outer shape of the fluid pump unit 14. Bach docking surface 24 faces outwardly from an elongate axis 26 of the docking unit body 22. In the embodiment illustrated herein, each docking surface 24 has a generally concave shape which is arranged to conform to the generally cylindrical configuration of the fluid pump unit 14. The docking unit body 22 has a docking end 28, which substantially conforms in shape to a portion of an end 30 (FIG. 2) of the fluid pump unit 14, The docking surface 24 of the docking unit 16 does not extend all the way around a circumference 32 of the fluid pump unit 14. [0081] In certain embodiments, only a contact portion 34 of the docking surface 24 at the docking end 28 of the docking unit 16 engages with the fluid pump unit 14. Other portions of the docking surface 24 can act as a guide when assembling and disassembling the fluid pump unit 14 from the docking unit 16 but do not engage or contact the oppositely feeing parts of the fluid pump unit 14. This limitation or minimization of a contact between the fluid pump unit openings 64 and the docking device 16 can minimize fluid flow obstruction and increase the efficiency of the fluid pump units 14.

[0082] The docking end 28 has an opening (“docking end opening”) 36 formed therein for a cable 38 associated with die fluid pump unit 14 to extend therefrom, The opening 36 for the cable 38 is positioned off-centre at a second end of the fluid pump unit 14. As best Seen in FIG. 3, a cable housing 42 extends from the docking end 28 of the docking unit 16, and is arranged to house all the cables 38 of the fluid pump units 14, The cable housing 42 defines a cable housing lumen (not shown) for housing the cables 38 of the individual fluid pump units 14, and optionally a cable of a functional unit (not shown) when included. The cable housing lumen also optionally houses a guide wire 44 extending through the docking unit body 22. At least one end of the cable housing 42 incorporates a sealing mechanism 46 (FIG. 3) to operatively seal the cable housing lumen from fluid infiltration The sealing mechanism 46 allows the cable 38 of each fluid pump unit 14 and any additional functional unit cables to extend through the cable housing lumen. The guide wire 44 may be made of any material, such as a shape memory alloy, e.g. nitinoL The cable housing lumen may further comprise a support structure (not shown) for providing separate paths for the cables 38 and the guide wire 44. The cable housing 42 may be a catheter. [0083] A cable management system (not shown) is operatively connected to the cable 38 of each fluid pump unit 14, and arranged to be retained outside of the patient, in use, for manipulation by a practitioner to move the cables 38 of each fluid pump unit 14 for assembly and/or disassembly of at least the device portion 18 of the system 10, or for any other purpose. [0084] In certain embodiments, the docking unit 16 has a docking unit lumen 48 extending longitudinally through the docking unit body 22. The docking unit lumen 48 may be positioned parallel to, or along the elongate axis 26 of the docking unit body 22, In certain embodiments, the docldng unit lumen 48 enables intravascular fluid injection, blood withdrawal directly from the docking device or the ability to couple to an additional functional unit In certain embodiments which include the additional function unit the additional functional unit comprises one or more of a sensor (e.g. for sensing temperature, pH, fluid flow), a drug delivery component a fluid drawing component and a fluid injection component and the like. The additional functional unit may be sized and shaped like a fluid pump unit 14 to enable coupling with the docking unit 16. In certain other embodiments, the docking unit 16 does not have a docking unit lumen 48. The docking unit body 22 is a non-expandable body of solid construction.

[0085] A retaining device 50 is provided on the docking unit 16 for retaining the fluid pump units 14 and the docking unit 16 in the assembled configuration. As shown, the retaining device 50 comprises a retaining ring 52 extending around the docking surface 24 and is sized to allow the fluid pump unit 14 to pass therethrough, in both directions (i.e, during assembly and disassembling). The retaining device 50 is sized and shaped to allow assembly and disassembly of die fluid pump units 14 and docking unit 16, The retaining ring 52 is resiliency biased towards tiie docking surface 24. The retaining ring 52 is angled with respect to the elongate axis 26 of the docking unit body 22. In certain embodiments, one or multiple retaining devices may be provided for each of the fluid pump units 14 or functional units couplable to the docking unit 16.

In certain embodiments, the retaining device 50 may be omitted.

[0086] Instead of, or in addition to, the retaining ring 52, the retaining device 50 may comprise any device associated with the docking unit 16, or the fluid pump unit 14, for holding or maintaining the fluid pump units 14 in the assembled configuration. In certain other embodiments, the retaining device 50 comprises any one or more of magnets, screws, hooks, clips, a ratchet mechanism, or the like. In certain embodiments, the retaining device 50 has an expandable configuration, such as a stent-like or other expandable scaffold. [0087] The system 10 further comprises an anchoring system 54 for releasably retaining the docking unit 16, with or without the fluid pump units 14 coupled thereto, in the conduit 12 of the patient In the embodiments illustrated in FIGS, 2 and 3, the anchoring system 54 comprises an anchor member 56 which is resilientiy biased away from the elongate axis 26 of the docking unit 16. The anchor member 56 is a ring, or a plurality of rings. In certain other embodiments, the anchor member 56 is an expandable device such as a balloon or an expendable frame. The anchor member 56 may be made of a shape memory alloy, such as Nitinol™. In certain embodiments, removal of the delivery sheath 20 results in deployment of the anchoring system 54. In other embodiments, the anchoring system 54 may be connected to, and extend from, the docking unit 16, or the fluid pump units 14.

[0088] Turning now to the fluid pump units 14, best seen in FIGS. 6-8. The fluid pump units 14 are arranged to pump fluid, such as blood, Each fluid pump unit 14 comprises an outer casing 58 having a first end 60 and the second end 40, and a longitudinal axis 62 extending between the first and second ends 60, 40. The fluid pump unit 14 comprises openings 64 defined in the outer casing 58 at the first end 60, and circumferentially in the outer casing 58 spaced from the first end 60. The openings 64 can function as fluid inlets or as fluid outlets, depending on the orientation of the system 10 relative to the fluid flow (e,g. blood flow) direction in the conduit 12. When the fluid pump unit 14 is delivered to the aorta such that the first end 60 is upstream of the fluid flow, the opening 64 at the first end 60 is an inlet, and the circumferentially positioned openings 64 are the outlet When the fluid pump unit 14 is delivered to the aorta such that the first end 60 is downstream of the fluid flow, the opening 64 at the first end 60 is an outlet, and tiie circumferentially positioned openings 64 are the inlet In other words, when the fluid flow (e.g. native blood flow) encounters the circumferential openings 64 before the first end opening 60, the first end openings 64 function as the outlet, and when the fluid flow encounters the first end openings 64 first, then these function as the inlet

[0089] In tiie embodiments illustrated, the circumferentially positioned openings 64 are defined in tiie outer casing 58 and comprise: a first circumferential opening 66, a second circumferential opening 68 and a third circumferential opening 70 (as best seen in FIG. 8). In other embodiments, any number of circumferential openings 64 can be provided. There may be a single circumferential opening 64, or a plurality of circumferential openings 64. The circumferential openings 64 are positioned such that they do not face the docking surface 24 when the fluid pump unit 14 and the docking unit 16 are in the assembled configuration. In other words, the openings 64 stop short of extending around the entire circumference of the outer casing 58. This can help to ensure an unhindered fluid flow into or out of die fluid pump unit 14. A distance between the first and the third circumferential openings 66, 70 is larger than a distance between die first and the second circumferential openings 66, 68, and the second and third circumferential openings 68, 70.. This larger spacing between the fust and third circumferential openings 66, 68 defines a portion free of openings on die outer casing 58, and which will face the docking surface 24 in the assembled configuration. The portion is circumferentially aligned with the plurality of openings 64 on die outer casing 58. In certain other embodiments, the position of the openings 64 differs from those illustrated. In certain other embodiments, die circumferential openings 64 are positioned all the way around the outer casing 58. In these embodiments, the docking unit 16 stops short of the level of the circumferential openings 64. [0090] The fluid pump unit 14 is further provided with a motor 72 (FIG. 6) housed in the outer casing 58. A diameter of the outer casing 58 and consequently die motor 72 is selected such that the combined diameter of the system 10 in the assembled configuration is less than a diameter of the aorta. There is also provided a motor shaft 74 connected to die motor 72 and an impeller 76 connected to the motor shaft 74 via its impeller shaft 77. The motor 72 is operatively connected to the motor shaft 74 for rotating the motor shaft 74 with the impeller 76. In this embodiment, the motor 72 is a 6 mm motor with a maximum rpm of 50,000. However, other motor 72 types are also envisaged to be within the scope of the present technology. In selecting the number and type of motors 72 for use with the present technology, a desired flow output is to be taken into consideration. So for a specific desired flow output in a given conduit, a single or combination of motors 72 is selected having a total flow output meeting die desired flow output. A flow rectifier 71 may also be provided in the fluid puny unit 14.

[0091] In other embodiments, the outer casing 58 comprises an outer structure (not shown) of the motor 72. In yet other embodiments, the outer casing 58 may house the impeller 76 only, with the motor 72 housed externally to die fluid pump unit 14 and connected thereto. Also in other embodiments (not shown), the fluid pump unit 14 Includes a cannula for fluid delivery. For example, the cannula may be used for drawing or pushing blood into specific conduits such as renal arteries, hepatic veins, etc.

[0092] The system 10 further comprises a computer system (not shown) having a processor (not shown) for controlling the operation of the motor 72. The motor 72 is electrically coupled to the processor by the cable 38, and powered by a power system 78, which will be described below. In certain embodiments, the motor 72 can be operable to provide a pulsed pumping effect

[0093] The outer casing 58 of the fluid pump unit 14 comprises a body 80 which is generally cylindrical (convex) and a cap 82 at the second end 40. The cap 82 is chamfered, has an asymmetric shape, and defines an opening 84 for the cable 38 to pass therethrough· This is best seen in FIG. 6. The cable 38 has been omitted from FIGS. 7 and 8 for clarity. In alternative embodiments, the outer casing 58 has a one-piece construction with the second end 40 having chamfered or asymmetric shape, such as a cone or a cone-like shape. The docking end 28 of the docking unit 16 has a complementary shape to the second end 40 (cap) of the fluid pump unit 14 such that rotational movement of the fluid pump unit 14 is inhibited when the fluid pump unit 14 and the docking unit 16 arc in the assembled configuration. The cable 38 extends from the second end 40 of the fluid pump unit 14, and more specifically from the cable opening 84 provided in the cap 82. The cable 38 is electrically connected to foe motor 72 housed therein. The cable opening 84 for foe cable 38 formed in the second end 40 is off-centre with respect to foe circumference 32 of the second end 40 of the fluid pump unit 14.

[0094] Although the system is illustrated as having three fluid pump units 14, and a corresponding three docking surfaces 24 on the docking unit 16, the system 10 may be provided with any number of fluid pump units 14 or docking surfaces 24. In certain other embodiments (not shown), the system 10 is provided with any number of fluid pump units 14, such as one, two, four, five, six, seven and eight fluid pump units 14, and the equivalent number of docking surfaces 24. In certain other embodiments, the system 10 is provided with one or more fluid pump units 14 and one or more other functional units, and an equivalent number of docking surfaces 24 On the docking unit 16. [0095] In the assembled configuration, and best seen in FIG. 10, the fluid pump units 14 are positioned radially about the elongate axis 26 of the docking unit 14, outwardly of the docking surfaces 24, with the longitudinal axes 62 of the fluid pump units 14 substantially parallel with one another, and/or the elongate axis 26 of the docking unit 16. The assembled configuration resembles a hub-spoke configuration in cross section.

[0096] The docking unit 16 and the fluid pump units 14 are moveable between the delivery configuration in which the longitudinal axes 62 of the fluid pump units 14 are aligned with the elongate axis 26 of the docking unit 16, and the assembled configuration in which the fluid pump units 14 are positioned radially about the elongate axis 26 of the docking unit 16. In this respect, the system 10 is fUrther provided with a docking mechanism 86 (FIG. 6) for controlling relative movement between the docking unit 16 and the fluid pump units 14. The docking mechanism 86 is arranged to enable both assembly and dis-assembly of at least the device portion 18 of the system 10, in vivo, in the patient

[0097] In certain embodiments, the docking mechanism 86 comprises the cable 38 extending from the second end 40 of the outer casing 58 of the fluid pump unit 14, through the docking end 28 of the docking unit 16. Optionally, the cable 38 is opcrably connectable to the cable management system for manipulating the cable 38 to effect relative movement between the fluid pump unit 14 and the docking unit 16. Alternatively, the cables 38 can be manipulated in any other way. The cable 38 is sufficiently stiff to allow pulling and pushing whilst avoiding buckling. As best seen in FIG. 11, each cable 38 comprises an outer sheath 88 defining a cable lumen 90, the cable lumen 90 housing at least one electrical wire 92, and a reinforcement wire 94. In other embodiments (not shown), there is no reinforcement wire in the cable 38, the reinforcement wire being replaced by reinforcement to the outer sheath 88.

[0098] The system 10 is further provided with the power system 78, in certain embodiments, for providing power to the fluid pump units 14, and/or the functional unit when present [0099] In certain embodiments, the power system 78 comprises a transcutaneous induction charging system. The induction charging system comprises a first, internal induction charger 96 (FIG. 12B) comprising an internal induction coil 98 electrically connected to the fluid pump units 14, and/or the functional unit, opcrably oouplable to an external induction charger 100 (FIG. 12A) having a second induction coil 102, complementary to the first induction coil 98. The first and/or second induction coils 98, 102 each contain a single coil. The use of multiple induction coils is not excluded. The external induction charger 100 may also be operatively connected to a battery pack 104 which is arranged to be charged through the first and second induction coils 98, 102. The external induction charger 100 may have any suitable shape such as a rectangular flat casing, or a toroidal flat casing, or other shapes. [0100] The external induction charger 100 is implemented as a wearable device 100 in certain embodiments, such as a watch. The wearable device may include at least one sensor (not shown) for measuring a physiological parameter of the patient such a pulse, a saturation rate, a blood pressure, true blood flow rate, inferred blood flow rate. The wearable device may further comprise a processor (controller) 106 operatively communicable with the battery 104 and optionally the sensors. In one embodiment, the wearable device is arranged such that external induction charger 100 is positioned on the dorsal aspect of the wrist of tire patient when wearing the wearable device on the wrist Other positions such as radio-ulnar articulation, other positions along the patient's arm, hand, leg or foot are not excluded from the scope of the invention. [0101] There may also be provided an internal controller (not shown), operatively connected to the first induction coil 98 by an electric wire 108. A battery (not shown) may also be provided for providing power to the internal controller and the first induction coil 98. The internal and/or external controllers can control the induction charging process between the first and second induction coils 98, 102. The internal and/or external controller may also be arranged to redistribute power to the fluid pump unit 14 and/or other parts of the system 10. In certain embodiments, the battery component 104 of the external induction charger 100 is removable from the external induction charger 100, allowing continuous use by exchanging a discharged battery for a second folly charged battery. The internal and/or external controller may also uplink or downlink with external communication devices such as cell phones, smart watches, smart household devices, and hospital linked monitoring apparatuses or systems. The internal controller is operatively connected to device by wire having a first section, arranged to be positioned subcutaneously, and a second section arranged to be positioned intravaseularly.

[0102] The internal controller may be operatively linked to the external controller in a wired or wireless fashion. The internal and/or external controllers may have additional function capabilities such as one or more of: monitoring a charge level of battery, monitoring or recording a vital sign o.g. pulse, saturation rates, systolic/diastoHc blood pressure, true blood flow rate, and device performance parameters : such as wattage or inferred blood flow rate. In certain embodiments, the wearable device is complemented by an external induction coil assembly (not shown) embedded within a bed mattress, onto which the patient may rest, or Into any other furniture, household appliance or any wearable device in close range of the patient during the night or day. In alternative embodiments, the power source comprises a battery. Other wired or wireless power charging methods are not excluded from the scope of the present invention. In certain embodiments, additional autonomous battery packs (not shown) may be provided and be added to the external induction charger for extending die operational battery lifetime of the device. In certain embodiments, the cable 38 or other wire connects the docking device 16 to the subcutaneous controller, and may have a fixed length.

[0103] Another embodiment of the system 10 is shown in FIGS. 13 and 14. This embodiment of the system 10 In FIGS. 13 and 14 differs from that of FIGS. 1-3 in that the docking surface 24 of the docking unit 16 defines an opening 110 in fluid communication with the docking unit lumen 48. hi use, the fluid will flow into the docking unit lumen 48, and through the opening 110 in the docking surface 24 to the fluid pump units 14, Further, the docking unit 14 of FIGS. 13 and 14 includes a cannula 112 extending from the end of the docking device 16. Coupling elements 116 such as magnets or any other connectors, are provided between the fluid pump units 14 and the docking surface 24 of the docking unit 16. In use, the rmnnul» 112 is arranged to be located inside the patient's conduit, such as the aorta, for drawing or propulsion of fluid. For example, blood can be drawn or pushed into any one of: the four heart chambers, any artery, any vein, any organ such as the bladder, the kidney, the liver, any body cavity large enough for accommodating the docking unit 16 and fluid pump units 14. A cannula anchoring system 114 can be provided (not shown) for securing the cannula 112 to the desired anatomical site. Cannula anchoring systems 114 can include any one or more of: a pig tail shaped eaimula end, deployable anchoring systems, a screwing system, or any other system. In certain embodiments, the fluid pump units 14 and the docking unit 16 are positioned in the descending aorta (FIG, 15), but may be positioned elsewhere along the aorta or any of the heart chambers, any artery, vein or cavity. In other embodiments, the cannula 112 is operatively connected to one or more of the fluid pump units (not shown), instead of the docking unit 16.

[0104] Power can be transferred through a contact or contactless method to the individual fluid pump units 14. There may be individual power wires extending from each pumping unit 14 to the subcutaneous controller.

[0105] In another embodiment, not shown, the system 10 is provided with a wire management system for varying a length of any of die wires or cables of the system 10 in use. In one embodiment, the wire management system (not shown) comprises a spring-loaded mechanism for wire retraction. In another embodiment, the wire management system comprises an elastic wire casing. The wire management system can accommodate for arm movements of the patient by varying the wire length, to reduce or minimize patient discomfort. The wire management system can be positioned subcutaneously. [0106] In another embodiment (not shown), the system 10 differs from the embodiment of FIGS.

1-3, in that it does not include a docking unit 16. The system 10 comprises four fluid pump units 14 for pumping the fluid which are arranged to be assembled together in the assembled configuration; and a connecting mechanism for securing the fluid pump units 14 in the assembled position, hi certain other embodiments, there are provided three fluid pump units 14. Any number of fluid pump units 14 can. be provided. The connecting mechanism comprises ««meeting elements acting between the coupling surfaces of the fluid pump units, hi certain embodiments, the connecting elements comprise magnets, clips, and the like.

[0107] In use, a method of delivering the system 10 to the conduit 12 of the patient comprises: providing the fluid pump units 14, and optionally the docking unit 16, in the delivery configuration and housed within the delivery sheath 20; and inserting the delivery sheath 20, the docking unit 16 and the fluid pump units 14 in the delivery configuration into the conduit 12 of tiie patient. When delivering the system 10 to the aorta, for example, the delivery sheath 20 can be inserted through the subclavian artery or the femoral artery. The delivery is percutaneous. Alternatively, the delivery may involve an arterial out-down. The method continues with retracting the delivery sheath 20 whilst maintaining the fluid pump unite 14, and optionally the docking unit 16, in the conduit 12 of the patient; and assembling the fluid pump units 14, and optionally the docking unit 16, into the assembled configuration whilst in the conduit 12. Retraction of the delivery sheath 20 may deploy the anchoring system 54. Alternatively, the anchoring system 54 can be deployed in any other way to position the docking unit 16 within the conduit 12, A portion of the anchor members 56 may push outwardly and contact an internal surface of the conduit 12, The assembling step of the method comprises manipulation of the cables 38 of each of the fluid pump unite 14 individually, to position them relative to each other, and optionally relative to the docking unit 16. More specifically, tension is applied to the cable 38 of each fluid pump unit 14, such as by pulling, to draw the fluid pump unit 14 into engagement with each other, or to the docking unit 16. In certain embodiments, the second end 40 of the fluid pump unit 14 engages with the docking end 28 of the docking unit 16. The docking surface 24 may act as a guide in this respect The method further continues with sending instructions to the motors 72 or to the processor or controllers to commence rotation. The motors 72 of the fluid pump units 14 may be controlled individually or as a single unit

[0108] The device portion 18 of the system 10, comprising the fluid pump units 14 and optionally the docking unit 16, are arranged to be delivered inside the patient, whilst other components of the system 10 arc arranged to remain on the outside of the patient, including one or more of: at least a portion of the cable housing 42, the cable management system, the computer system, the processor, and at least aportion ofthe power system 78.

[0109] A method of removal of the fluid circulation support system 10 comprises disassembling the fluid pump units 14 flora the docking unit 16, or flora each other, by applying a force to the cables 38 to push the fluid pump units 14 away from the docking unit 16 or flora each other, and positioning the fluid pump units 14, and optionally the docking unit 16, such that they are aligned in series, Once they are aligned, the docking unit 16 and/or the fluid pump units 14 may be retrieved back through the conduit 12 or another conduit of the patient The docking unit 16 and the fluid pump units 14 may be retrieved through the delivery sheath 20, or by any other mechanism. [0110] It should be appreciated that the Invention is not limited to the particular embodiments described and illustrated herein but includes all modifications and variations falling within the scope of die invention as defined in the appended claims.

Claims

1. A system for supporting fluid circulation and deliverable tb a fluid carrying conduit of a patient, the fluid circulation support system comprising:

• at least two fluid pump units for pumping the fluid, each fluid pump unit having a longitudinal axis;

• a docking unit comprising a docking unit body having at least two docking surfaces, each docking surface arranged to be couplable with at least a portion of at least one of the fluid pump unite in an assembled configuration, wherein each docking surface faces outwardly from an elongate axis of the docking unh body, and wherein at least a portion of the docking surface conforms in shape to at least a portion of the fluid pump unit, such that when in the assembled configuration, the at least two fluid pumps are positioned radially about the elongate axis of the docking unit, and outwardly of the at least two docking surfaces

2. The system of claim 1, wherein the docking unit and the at least two fluid pump units are arranged such that the longitudinal axes of the at least two fluid pump units substantially align with the elongate axis of the docking unit when in the assembled configuration.

3, The system of claim 1 or claim 2, wherein the docking unit and the fluid pump units are sized such that a diameter of the assembled system is less than a diameter of the conduit of the patient into which the system is deliverable.

4. The system of any of claims 1-3, wherein the docking unit and the at least two fluid pump units are moveable between a delivery configuration in which the elongate axis of the docking unit and the longitudinal axes of the fluid pump units are substantially aligned, and the assembled configuration in which the at least two fluid pump units are positioned radially about the elongate axis of the docking unit

5. The system of claim 4, further comprising a delivery sheath for housing the fluid pump units and the docking unit to the delivery configuration, and arranged to be deliverable into the conduit of the patient, the delivery sheath being arranged to be removeable.

6. The system of any of claims 1-5, wherein the fluid pump unit comprises an outer casing having a first end and a second end, the outer casing having openings defined in the outer casing to act as a fluid inlet and a fluid outlet to use, and a motor housed to the outer casing.

7. The system of claim 6, wherein the motor comprises a shaft and an impeller rotatably moveable about the shaft.

8, The system of claim 6 or claim 7, wherein the openings comprise one opening defined at the first end of the outer casing, and at least one other opening defined circumferentially in the outer casing.

9. The system of claim 8, wherein the at least one other opening defined circumferentially in the outer casing stops short of extending around the entire circumference of the outer casing.

10. The system of claim 9, farther comprising a portion, circumferentially aligned, and between the at least one other opening defined circumferentially in the outer casing, which portion feces flic docking surface when the fluid pump unit and the docking unit are in the assembled configuration.

11. The system of any of claims 6-10, whereto the outer casing comprises a convex and asymmetrically shaped second end, and the docking surface has a docking end having a complementary shape to the second end for receiving the second end thereto.

12. The system of any of claims 1-11, wherein the docking unit comprises a docking device lumen extending longitudinally through the docking unit body, and optionally a guide wire extending through the docking device lumen,

13. The system of any of claims 1-12, further comprising a retaining device for retaining the at least two fluid pump units and the docking unit in the assembled configuration.

14. The system of claim 13, wherein the retaining device comprises a retaining ring extending around the docking surface.

15. The system of daim 13 or claim 14, wherein the retaining ring is resiliently biased towards the docking surface.

16. The system of any of claims 1-15, farther comprising a functional unit, also couplable with the docking unit, the functional unit being operable to perform any one or more of the following functions: fluid Injection or drawing fluid, drug delivery, physiological sensing (temperature, pH, fluid flow).

17. The system of any of claims 1-16, further comprising a power source fin providing power to the fluid pump units, and/or the functional unit

18. The system of claim 17, wherein the power source comprises an induction coil electrically connected to the fluid pump units, and/or the functional unit, operably couplable to an external induction coil and a battery.

19. The system of claim 18, wherein the external induction coil and the battery are implemented as a wearable device.

20. The system of claim 19, wherein the wearable device includes at least one sensor for measuring a physiological parameter of the patient, selected as one or more of: a pulse, a saturation rate, a blood pressure, true blood flow rate, inferred blood flow rate.

21. The system of claim 19 or claim 20, wherein the wearable device further comprises a processor operatively communicable with the battery and optionally the sensors.

22. The system of any of claims 1-21, farther comprising a docking mechanism for controlling relative movement between the docking unit and the at least two fluid pump units, the docking mechanism arranged to move the at least two fluid pump units between a delivery configuration in which the elongate axis of the docking unit and the longitudinal axes of the fluid pump units are aligned, and the assembled configuration in which the at least two fluid pump units are positioned radially about the elongate axis of the docking unit

23. The system of claim 22, wherein the docking mechanism, comprises a cable connected to each fluid pump unit and optionally opeiably connectable to a cable management system for manipulating the cable to effect relative movement between each one of die fluid pump units and the docking unit

24. The system of claim 23, wherein the cable extends from the outer casing of the fluid pump unit and through the docking end of the docking unit.

25. The system of claim 24, wherein the cable extends from a position at the second end of the outer casing of the fluid pump unit which is off-centre relative to a circumference of the outer casing.

26. The system of elflim 24, further comprising a cable housing, extending beyond the docking end of the docking unit, for housing the cables of each fluid pump unit

27. The system of any of claims 23-26, wherein each cable comprises an outer sheath housing at least one electrical wire, and optionally a reinforcement wire.

28. The system of any of claims 23-27, farther comprising a cable management system, operatively connected to the cable of each fluid pump unit, and arranged to be retained outside of the patient for manipulation by a practitioner to manipulate the cables of each fluid pump unit

29. The system of any of claims 1-28, further comprising an anchoring system for releasably retaining the docking unit in the conduit of die patient.

30. The system of claim 29, wherein the anchoring system comprises an anchor member which is rcsiliontly biased away from the elongate axis of the docking unit,

31. The system of claim 30, wherein the anchor member comprises a ring connected to the docking unit

32. A fluid pump unit for a fluid circulation support system, die fluid pump unit comprising an outer casing having a first end and a second end, the outer casing having at least two openings defined in ti» outer casing to act as a fluid inlet and a fluid outlet, respectively, in use, and a motor housed in the outer casing.

33. The fluid pump unit of claim 32, wherein the motor comprises a shaft and an impeller rotatably moveable about the shaft, and optionally the motor including a motor casing.

34. The fluid pump unit of claim 32 or claim 33, wherein the openings comprise one opening defined at the first end of the outer casing, and at least one other opening defined circumferentially in the outer casing.

35. The fluid pump unit of claim 34, wherein the at least one other opening defined circumferentially in the outer casing stops short of extending around the entire circumference of die outer casing.

36. The fluid pump unit of claim 35, further comprising a portion, circumferentially aligned, and between the at least one other opening defined circumferentially iri the outer casing, which portion feces a docking surface of a docking unit when the fluid puny) unit and the docking unit are in an assembled configuration.

37. The fluid pump unit of any of claims 32-36, wherein the outer casing comprises a convex and asymmetrically shaped second end.

38. The fluid pump unit of claim 37, Anther comprising a cable extending from the second end, and from a position which is off-centre relative to a circumference of the second end.

39. The fluid pump unit of claim 38, the cable comprising an outer sheath defining a lumen, the lumen housing a reinforcement wire and electrical wires in electrical contact with the motor.

40. A docking unit for a fluid circulation support system, the docking unit comprising a docking unit body having at least two docking surfaces, each docking surface arranged to be couplable with at least a portion of at least one fluid pump unit in an assembled configuration, wherein each docking surface faces outwardly from an elongate axis of the docking unit body.

41. The docking unit of claim 40, the docking unit body further comprising a docking end having an opening for receiving a cable of the fluid pump unit therethrough.

42, The docking unit of claim 40 or claim 41 , further comprising a cable housing, extending beyond the docking end of the docking unit, for housing the cables of each fluid pump unit