WO2021062566A1

WO2021062566A1 - Modular impeller system for fluid circulation

Info

Publication number: WO2021062566A1
Application number: PCT/CA2020/051677
Authority: WO
Inventors: Gabriel GEORGES
Original assignee: Puzzle Medical Devices Inc.
Priority date: 2019-10-05
Filing date: 2020-12-05
Publication date: 2021-04-08

Abstract

Device for assisting a flow of a fluid within a conduit of a body, comprising: An impeller hub, structured to be connectable to an impeller vane and being sized, shaped and dimensioned to be implanted into the conduit of the body via transcatheter manipulation. At least one impeller vane structured to be connectable to the impeller hub and sized, shaped and dimensioned to be implanted into the animal body via transcatheter manipulation. The impeller hub and the at least one impeller vane, when interconnected, forming an impeller, the impeller being sized, shaped and dimensioned to be operable within the conduit of the animal body. A motor having an output shaft operatively connectable to the impeller hub to operate the impeller.

Description

MODULAR IMPELLER SYSTEM FOR FLUID CIRCULATION CROSS-REFERENCE

[0001] The present application is claims priority to United States Provisional Patent Application Serial No. 62/911,257, entitled “Modular Impeller System for Fluid Circulation ”, fded October 5, 2019; the entirety of the contents thereof is incorporated herein by reference for all purposes.

FIELD

[0002] The present disclosure relates to systems and devices for influencing fluid circulation in a patient, specifically, but not exclusively, to ventricular assist devices.

BACKGROUND

[0003] Fluid carrying conduits in patients, such as blood vessels or other conduits near the heart, liver or kidneys carrying fluids other than blood (e.g., urine, lymph, etc.), may require fluid flow influencing (e.g. an increase in fluid flow rate, a decrease in fluid flow rate, a stoppage of fluid flow, etc.) in various medical situations.

[0004] Heart failure is an example of a common such situation. In patients with heart failure, their heart becomes unable to pump enough blood to meet their body’s needs for blood and oxygen.

[0005] Heart failure is a disease affecting upwards of 6 million Americans and 26 million people worldwide at any given time. There is no cure. For those suffering from heart failure, their ability to function in everyday life and their overall quality of life steadily and inevitably declines. There may be times of rapid deterioration. Even with the best of medical care, heart failure sufferers’ symptoms will slowly, inevitably progress. They will rapidly become limited in their activities. At some point in time, they will experience increasing symptoms of the disease even at rest and under optimal medical therapy. People with end-stage heart failure disease currently have a 2-year estimated chance of survival of only 20%.

[0006] To try to improve this somber forecast of the probable course and outcome of the disease, multiple strategies for caring for people having heart disease have been developed. Such strategies include both short-term mechanical patient support options, as well as longer-term patient support options. Unfortunately, none of the options currently available are optimal. [0007] Prior to review of the current conventional treatment possibilities, it should be noted that all such treatments are surgical in nature. They may be carried out on a patient suffering from the disease either via “open surgery” (i.e., the traditional surgical method of the cutting of skin and tissues so that the surgeon has a full view of the structures or organs involved) or via “minimally invasive surgery” (i.e., newer surgical techniques that do not require large incisions). Examples of minimally invasive surgical techniques are transcatheter techniques, in which a catheter (e.g., a relatively long flexible tube) is inserted into the patient’s body and the intervention is performed through the lumen (i.e.. the hollow cavity) of the catheter at a site distal to (e.g., away from) the catheter insertion site. As compared with open surgical techniques, transcatheter techniques generally are lower risk to the patient, shorter in time for the surgeon to perform, and have shorter patient recuperation times. They are usually preferred by patients.

[0008] One current treatment possibility for heart disease is a heart transplant. Heart transplantation involves the removal of a patient’s diseased heart and its replacement with a 25 healthier heart from a heart donor. There are, however, an extremely limited number of donor hearts available. In North America for example, only about 3,000 donor hearts are available each year. So, heart transplantation is not an option which is generally available to patients as the number of donor hearts is far less than the number of sufferers of the disease. Further, heart transplantation obviously requires very invasive open surgery. It carries additional significant risks, including (but in no way limited to) transplant coronary artery disease and life-long suppression of the recipient’s immune system. For all of these reasons, heart transplantation is in most cases limited to younger patients, and therefore younger patients are prioritized on heart transplant lists.

[0009] Another current treatment possibility for heart disease is through the removal of a patient’s diseased heart and its replacement with an artificial heart device (typically known as a “total artificial heart”). While the number of total artificial hearts is not limited (as is the case with donor human hearts) as they are manufactured devices, at the moment their use is limited to being only temporary. No total artificial heart is available for permanent implantation. Thus, total artificial hearts are used in patients who are in the end-stages of heart disease, but for whom no donor heart is yet available. Their use is quite limited, as the number of donor hearts is limited. In addition, implantation of a total artificial heart still requires very invasive open surgery, and carries risks as noted above. There are very few total artificial heart products currently available for use in patients. One product is the SynCardia™Temporary Artificial Heart. Another potential product, which is still in development, is the Carmat™artificial heart.

[0010] A third current treatment possibility for heart disease, and the most common, is through the implantation and use of what is known as a “Ventricular Assist Device” (commonly abbreviated to and referred to as a ‘VAD’). A VAD is a mechanical pump that is surgically implanted within a patient to help a weakened heart pump blood. Unlike a total artificial heart, a VAD does not replace a patient’s own heart, instead it helps the patient’s native heart pump blood. VADs may be used to help the left side of a patient’s heart, in which case they are known as LVADs. Or, they may be used to help the right side of a patient’s heart, in which case they are known as RVADs. LVADs are far more commonly used. Currently, VADs may either be used as a bridge until a heart transplant can be performed (as is the case with total artificial hearts) or they may be used long term in patients whose condition makes it impossible to receive a heart transplant or who require immediate long-term support. There are different types and configurations of VADs, some of which will be discussed below.

[0011] Common to almost all currently available VADs is that their implantation requires open surgery, and carries the downsides and risks thereof noted above, and others. The complication rate and the mortality rate associated with the use of VADs are both significant. For example, patients are at risk of embolic stroke (e.g., a stroke caused by the blockage of a blood vessel due to a blood clot having formed), for amongst other reasons, the positioning of a VAD at the apex of the heart. Patents are also at risk of a cerebral (i.e. brain) or gastro- intestinal hemorrhage as most VADs pump blood continuously (as opposed to a normal heart, which pumps blood in pulses). This continuous pumping of blood causes the patient’s blood vessels to become more fragile (and thus prone to hemorrhaging) and also causes a decrease in the patent’s von Willebrand factor (which is a molecule in human blood that is part of the process to prevent and stop bleeding). Further, owing to the complexity of the VAD implantation surgery, VADs are only implanted in specialized centers. Indeed, the number one reason for patients refusing to undergo VAD implantation is the patient’s fear of such invasive implantation surgery and the complications arising therefrom. For all of these reasons, although more than 250,000 heart disease suffers in North America alone could benefit from VAD implantation, there are less than 4,000 yearly VAD implants in the United States.

[0012] All of these generations of VADs described above that are currently in use (or previously had been used) require (or required) invasive classic open surgery (e.g., a median sternotomy or a less invasive mini-thoracotomy). During the implantation procedure, a VAD is surgically attached (e.g., sutured) to the heart while the main VAD body remains external to the patient’s vasculature (e.g., heart and blood vessels). The pump inlet of the VAD is sutured to the left or right ventricle of the heart (depending on whether the VAD is an LVAD or an RVAD) and the outflow tubing from the VAD is sutured to the aorta (in the case of an LVAD) or the pulmonary artery (in the case of an RVAD).

[0013] As was described above, however, patients prefer minimally invasive transcatheter interventions to open surgery. And thus, the most recent efforts in the development of mechanical support strategies for people with heart disease have been made towards the development of pumps that do not require open surgery, but rather could be implantable transcatheter.

[0014] Currently, the only commercial product that can be implanted transcatheter is the Impella™ family of micro-pump devices from Abiomed™. An Impella device has a single micro axial pump (e.g., having an impeller) with a cannula (e.g., a small tube-like structure). The device is implanted within the left ventricle (in the case of an LVAD) or right ventricle (in the case of an RVAD) of the heart so as to cross the aortic valve (in the case of an LVAD) or tricuspid and pulmonary valve (in the case of an RVAD). The inlet of the pump is within the ventricle or within the vessels that discharge fluid into the ventricle and the outlet of the pump is outside of the heart, in the aorta (in the case of an LVAD) and in the pulmonary artery (in the case of an RVAD). As the pump impeller turns, blood is drawn into the device through the pump inlet. The blood then travels under pressure having been imparted by the pump through the cannula and exits the device through the pump outlet in the aorta or pulmonary artery (as the case may be). In this manner, the VAD provides pumping assistance to the ventricle of the heart.

[0015] An Impella device is implanted via a percutaneous procedure. In a percutaneous procedure access to the patient’s internal organs is made via needle-puncture of the skin (e.g., via the well- known conventional Seldinger technique). Typically, in such procedures, the needle-puncture site is relatively remote from the actual internal organs that the surgeon will be operating on. For example, although it is the heart that a surgeon will be operating on, the initial needle puncture of the skin takes place in the patient’s groin area so that the surgeon can access the patient’s vasculature through the femoral vessels. Once access is obtained, the surgeon can advance the necessary tools to conduct the surgical procedure through the patient’s vasculature to their heart. The surgeon then conducts the procedure on the heart, usually via wires extending from the tools, travelling through the patient’s vasculature and outside of the patient’s body via the access opening that the surgeon had previously made. Once the procedure has been completed, the surgeon removes the tools from the patient’s vasculature in the same manner. In such procedures, access via the femoral artery (in the patient’s groin area) or the axillary artery (about the patient’s clavicle) are more common.

[0016] One difficulty that arises with respect to such percutaneous procedures and devices such an Impella device, is that the size of the device is significantly limited because of the remote peripheral insertion location of the device (through femoral or axillary artery, as the case may be). /. e.. the size of the structures that will travel through the patient’s blood vessels is limited to being only slightly larger than those vessels themselves, as those vessels can only stretch a limited amount before they will become damaged. In the context of an Impella device, what this means is that the actual physical size of the pump (including the motor) is limited since the pump must travel through the patient’s blood vessels to the patient’s heart.

[0017] This, in turn, limits the actual physical size of the cannula of the pump through which the pumped blood will flow. Thus, in order for the Impella device pump to provide a sufficient volume of blood flow through the cannula to adequately assist the patient’s heart, the impeller of the pump will have to rotate at a very high speed. (Generally, the higher the rotation speed of the impeller, the more blood the pump will pump.) This high impeller rotation speed can be problematic, however. High impeller rotation speed generates substantial shear stress forces on the blood elements being pumped, leading to known detrimental phenomena such as platelet activation, von Willebrand factor multimer destruction, destruction of red blood cells and thrombus formation. All of which can lead to embolic strokes or pump thrombosis, as described above.

[0018] In view of this, improved transcatheterly-implantable VAD solutions are currently in development (Hsu et al, 2012). Such devices include devices developed by Magenta Medical™ or Second Heart Assist™ and the recently approved Heartmate™ PHP by Abbott™. These devices all have a common goal of overcoming the limitations of the Impella devices by using impellers that have the capability of being expanded in vivo. In this manner, the device can be implanted transcatheter with the pump impeller being in a small configuration (sufficient to be able to travel through the patient’s blood vessels without causing damage). At the implantation site, the impeller then can be expanded to be of a larger size. In this manner, the impeller can be operated at relatively lower speeds (as compared with the one of an Impella device), as the expandable impeller, in its operating configuration is relatively larger than the Impella device impeller. (As, generally, larger diameter impellers need only rotate at a slower speed than a smaller diameter impeller would have to to pump the same amount of blood, these devices attempt to reduce the risks present in devices with high-speed impellers.)

[0019] A first approach to deploy such a device is based on structural folding of some impeller components, where mechanical joints allow the deployment of the system. This operating basis of such a design enables a wide range of geometries and materials for the design of the impeller, enabling the impeller designer to have an increased focus on hydraulic efficiency. Specifically, O. Reitan proposed a device where the deployment of the impeller blades resides on rotational joints fixed to a central hub which enables a large dimensional gap between the stored and deployed configuration (Reitan, 1998). This enables the deployment of a larger impeller with a lower rotational speed ensuring sufficient flow with minimal impact to blood components. However, mechanical joints on such devices often represent a geometric discontinuity where blood stagnation elevates the risk of thromboembolism, blocking the clinical viability of such devices.

[0020] Foldable devices where the impeller and housing deployment relies on an inflatable mechanism have also been proposed (Khaw & Li, 2003; Siess, 2014), but the requirement of a permanent supply of fluid to maintain the inflation pressure limits the portability of the device. Furthermore, the durability of an impeller encompassing complex and multiple mechanical joints has yet to be proven in the clinical setting. In case of thrombus formation, endothelialization or platelet aggregation on the joint surfaces, joint movement may be hindered and threaten device retrieval.

[0021] Several patents teach compressing the impeller blades to achieve the stored configuration using flexible components. The deployment is then realized by the extraction of the device from a cannula (McBride et al, 2013) or through the expansion movement of the impeller housing (Toellner, 2016; Wiessler et al, 2015). While these flexible devices globally offer simpler deployment of uniform geometries, their bendable regions are subject to higher stress levels in the stored configuration and the flexibility of the material can lead to additional bending under high load implying a limited hydrodynamic efficiency. Additionally, most foldable devices are based on a radial compression of the impeller blades, which can be done up to a certain limit bound by the material properties. This compression limitation complexifies the design: it impacts the diameter range of the device which needs to be in accordance with clinical requirements of a peripheral implant. This geometrical impact restricts once again the portion of the impeller design which can be driven towards hydraulic efficiency. There are also concerns over the durability of the flexible impellers, compared to all impellers used in currently approved devices which are made of hard plastics such as PEEK or titanium and thus do not suffer from durability issues.

[0022] In view of the aforementioned drawbacks of current and currently proposed impeller designs for such devices, improved designs would be desirable.

SUMMARY

[0023] It is an object of the present technology to ameliorate at least some of the inconveniences present in the prior art.

[0024] It is a further object of the present technology to provide devices with an improved impeller design at least in one aspect as compared with at least one design present in the prior art.

[0025] According to certain aspects and embodiments defined below and in the claims, there are provided systems and methods for fluid circulation influencing. In certain aspects and embodiments, the abovementioned inconveniences are ameliorated, reduced or avoided.

[0026] Herein, amongst other things, is proposed a novel device deployment scheme, where multiple parts of the impeller are delivered longitudinally and can be sequentially assembled within the vasculature. Such as design may overcome at least one of the issues with previous device designs. The proposed construction enables larger flexibility in terms of impeller design since the dimensional limitation bound by the vessel length is much smaller. This also enables the choice of a material driven towards higher performance of a minimally invasive fluid circulation device, without any constraints of foldability.

[0027] The present technology is at least based in part on the developers’ observations and findings that providing the patient with a large diameter pump that provides the required flow rate can reduce the induced shear rate on blood elements compared to smaller diameter pumps, thereby reducing the chances of hemolysis, platelet activation, clotting factors destruction and/or thrombosis. This is achieved partly by a lower pump speed for the larger pumps (6000-10,000rpm) compared to smaller diameter pumps (e.g., 25, 000-50, OOOrpm).

[0028] Larger pumps however typically require an open surgical approach because they are too large to be implanted via a transcatheter technique, which requires the device to be fitted inside a patient’s peripheral arteries (e.g., femoral or axillary arteries). [0029] The present technology is designed to provide the patient with a larger hemodynamic support system while preserving the possibility of percutaneous transcatheter implantation. This is achieved through a modular device which can be assembled inside the patient.

[0030] From one aspect, there is provided a system for influencing fluid circulation and deliverable to a fluid carrying conduit of a patient, the fluid influencing system comprising: at least two modular impeller vanes for pumping the fluid; a hub comprising a core 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 modular blades in an assembled configuration, wherein at least a portion of the docking surface conforms in shape to at least a portion of the fluid modular blade, such that when in the assembled configuration, the at least two impeller vanes are positioned radially about the elongate axis of the core, and outwardly of the at least two docking surfaces. In certain embodiments, there are provided three fluid modular blades. In certain embodiments, there are provided any number of fluid modular blades. In certain embodiments, there are provided 4, 5, 6, 7, 8, 9 or 10 modular blades.

[0031] In certain embodiments, the core and the at least two fluid modular blades are arranged such that the longitudinal axes of the at least two fluid modular blades substantially align with the elongate axis of the core when in the assembled configuration.

[0032] In certain embodiments, the core and the fluid modular blades are sized such that a diameter of the assembled fluid modular blades and the core is less than a diameter of the conduit of the patient into which the system is deliverable. In certain embodiments, the docking unit and the fluid modular blades are sized such that a diameter of the assembled fluid modular blades and the core about the same as a diameter of the conduit of the patient into which the system is deliverable. In certain embodiments, the core and the fluid modular blades are sized such that a diameter of the assembled fluid modular blades and the core 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.

[0033] In certain embodiments, the core and the at least two fluid modular blades are moveable between a delivery configuration in which the elongate axis of the core and the longitudinal axes of the fluid modular blades are substantially aligned (in series), and the assembled configuration in which the at least two fluid modular blades are positioned radially about the elongate axis of the core (in parallel). [0034] In certain embodiments, when in the delivery configuration, the vanes are positioned distally to the interventionist and the central hub, proximally.

[0035] In certain embodiments, the system further comprises a delivery sheath for housing the fluid modular blades and the core in the delivery configuration and arranged to be deliverable into the conduit of the patient, the delivery sheath being arranged to be removeable.

[0036] In certain embodiments, the modular vanes are functionally attached to a guidewire system that allows them to be controlled through a transcatheter manipulation.

[0037] In certain embodiments, the guidewires pass through the central hub before exiting the patient’s vessel. In these embodiments, pulling or pushing the guidewires attached to the modular vanes translates into vane movement towards or away from the central hub.

[0038] In certain embodiments, the functional attachment of the vanes to the central hub is achieved through but not limited to a slide-in mechanism, a clip-on mechanism, a magnetic attraction, a friction seal, a ball-in-socket attachment, a screw-in mechanism or a latch system.

[0039] 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.

[0040] In certain embodiments, the impeller vanes are composed of a single solid shape.

[0041] In certain embodiments, the impeller vanes are composed of a single flexible shape.

[0042] In certain embodiments, the impeller vanes are composed of multiple modular elements. In these embodiments, the impeller vane sub-units are functionally attached one to another. In these embodiments, functional attachment of the vanes to one another is achieved through but not limited to a slide-in mechanism, a clip-on mechanism, a magnetic attraction, a friction seal, a ball- in-socket attachment, a screw-in mechanism or a latch system.

[0043] In certain embodiments, the impeller vane sub-units are composed of a single solid shape.

[0044] In certain embodiments, the impeller vane sub-units are composed of a single flexible shape. [0045] In certain embodiments, once functionally attached to the central hub, the vanes can functionally detach from their respective guidewires.

[0046] In certain embodiments, a motor is positioned outside of the vessel where the device is implanted. In these embodiments, the rotation of the motor is transferred to the system through a flexible drive shaft.

[0047] In certain embodiments, the central core is directly attached to a motor inside the vessel.

[0048] In certain embodiments, the assembled impeller is surrounded by a vessel protection cage; wherein the cage around the impeller serves to prevent the impeller from making contact with the vessel wall and wherein the cage can conform to a collapsed form during delivery and an expanded form during deployment of the system.

[0049] In certain embodiments, the cage is functionally attached to the central core hub.

[0050] In certain embodiments, the cage around the impeller allows for device anchoring in the vessel wall.

[0051] In certain embodiments, the system in implanted percutaneously.

[0052] In certain embodiments, the system is implanted in the descending aorta or pulmonary veins and utilized as a left ventricular assisting device.

[0053] In certain embodiments, the system is implanted in the vena cava or pulmonary arteries and utilized as a right ventricular support.

[0054] In certain embodiments, the system is implanted in the vena cava and utilized as a renal venous decongestion device.

[0055] In certain embodiments, the system is implanted in the abdominal aorta and utilized as a renal perfusion enhancement device.

[0056] 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 clearly 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 10 specified features or components with or without the other. For example, “A and/or B” is to be taken as specific disclosure of each of (i) A, (ii) B and (iii) A and B, just as if each is set out individually herein.

[0060] In the context of the present specification, the words “first”, “second”, “third”, etc. have been used as adjectives only for the purpose of allowing for distinction between the nouns that they modify from one another, and not for the purpose of describing any particular relationship between those nouns. Thus, for example, it should be understood that, the use of the terms “first module” and “third module” is not intended to imply any particular order, type, chronology, hierarchy or ranking (for example) of/between the module, nor is their use (by itself) intended imply that any “second module” must necessarily exist in any given situation.

[0061] Implementations of the present technology each have at least one of the above-mentioned objects and/or aspects, but do not necessarily have all of them. It should be understood that some aspects of the present technology that have resulted from attempting to attain the above-mentioned object may not satisfy this object and/or may satisfy other objects not specifically recited herein.

[0062] Additional and/or alternative features, aspects and advantages of implementations of the present technology will become apparent from the following description, the accompanying drawings and the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0063] For a better understanding of the present technology, as well as other aspects and further features thereof, reference is made to the following description which is to be used in conjunction with the accompanying drawings, where:

[0064] FIG. 1 illustrates a side view of a system comprising a core, two modular vanes and an expandable cage when in an assembled configuration, according to certain embodiments of the present technology; [0065] FIG. 2 illustrates an orthogonal view of a system comprising a core, two modular vanes and an expandable cage when in an assembled configuration, according to certain embodiments of the present technology;

[0066] FIG. 3 illustrates a front view of a system comprising a core, two modular vanes and an expandable cage when in an assembled configuration, according to certain embodiments of the present technology;

[0067] FIG. 4 illustrates a side view of a system comprising a core, two modular vanes and an expandable cage when in a delivery configuration, according to certain embodiments of the present technology;

[0068] FIG. 5 & 6 illustrate the assembly sequence of a first modular vane in a system comprising a core and two modular vanes, according to certain embodiments of the present technology;

[0069] FIG. 7 illustrates an orthogonal view of an isolated first modular vane, according to certain embodiments of the present technology;

[0070] FIG. 8 illustrates a complimentary orthogonal view of an isolated first modular vane, according to certain embodiments of the present technology;

[0071] FIG. 9 illustrates an example of a latch coupling mechanism between the impeller core and a first vane, according to certain embodiments of the present technology;

[0072] FIG. 10 illustrates a side view of a system comprising a central core and a first two-subunit modular vane, when in the delivery configuration, according to certain embodiments of the present technology;

[0073] FIG. 11 & 12 illustrates a side view of an example assembly sequence of a multiple sub unit modular vane, in a system comprising a central core and a first two-subunit modular vane, according to certain embodiments of the present technology. In these figures, the two-subunits of the modular impeller vane are guided by guidewires and operationally linked by magnets, according to certain embodiments of the present technology.

[0074] FIG. 13 illustrates a side view of a system comprising a core, two modular vanes and an expandable cage when in an assembled configuration, when the motor driving the assembled impeller is separated from the impeller by a flexible driveshaft, according to certain embodiments of the present technology.

DETAILED DESCRIPTION

[0075] The present disclosure is not limited in its application to the details of construction and the 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", "comprising", 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.

[0076] Broadly, there is provided a modular pumping device that can be delivered in place within an animal (human) body an in unassembled state and can be assembled in vivo within the vasculature of the body.

[0077] Referring to FIG. 1, in this embodiment, the device 100 comprises an impeller 101 including an impeller hub 102, a first vane 104, a second vane 106, a cage 108, and a motor 110. The motor 110 has an output shaft 112. In Fig. 1, cage 108 is in the expanded configuration. The device 100 is shown in an assembled state (configuration).

[0078] Referring to FIG 2, the impeller hub 102 has a first channel 114 therein into which an extended portion 120 of the vane 106 has been received. The extended portion 120 of vane 106 has been slid into the first channel 114 to provide a mechanical interlock therebetween, to secure the vane 106 to the impeller hub 102. The vane 106 also has a portion 116 with a surface 118 that is sized and shaped to mate with an exterior surface 122 of the impeller hub 102 when the vane 106 has been secured to the impeller hub 102. Output shaft 112 is also shown extending away from the impeller hub 102.

[0079] Referring to FIG. 3, the vane 104 and the impeller hub 102 have a similar relationship to the vane 106 and the impeller hub 102. Thus, impeller hub 102 has a second channel 115 therein into which an extended portion 128 of vane 106 has been slid to provide a mechanical interlock therebetween. Thus, the vane 104 has been secured to the impeller hub 102. The vane 104 has a portion 126 with a surface 127 that is sized and shaped to mate with the exterior surface 122 of the impeller hub 102 when the vane 104 has been secured thereto.

[0080] Referring to FIG. 4, the device 100 is showing in an unassembled state for delivery. The unassembled device 100 is contained within a delivery sheath 130. In this embodiment, within the delivery sheath, in order of delivery are vane 106, vane 104, and impeller hub 102. A guide wire 132 is releasably attached to vane 106 and vane 104 and passes through a central opening (FIG. 5) in the impeller hub.

[0081] Referring to FIG. 5, the device 100 has been delivered unassembled into place. The guidewire 132 may be manipulated to cause extended portion 120 of vane 104 to slide into channel 114 in impeller hub 102 to attached the vane 104 thereto. Referring to FIG. 6, vane 104 has been connected to impeller hub 102 via guidewire 132 having been manipulated to have the extended portion 116 of the vane 104 slide into the channel 114 and be retained therein. (Similarly, although not shown, vane 106 may be connected to impeller hub 102 to form impeller 101.)

[0082] Referring to Fig. 8, vane 104 has a tab 134 to be used to secure the vane 104 to the impeller hub 102 once the extended portion 116 has been fully slide into the channel 114. Referring to Fig. 9, there is a complimentary slot 136 located in the impeller hub 102 body to received and retain the tab 134 of vane 104.

[0083] Referring to FIG. 10, another embodiment, device 100 is shown in an unassembled state for delivery. The unassembled device 100 is contained within a delivery sheath 130. In this embodiment, vane 104 is itself of a modular construction, comprising two component parts 142 and 144. A guidewire 132 is attached to each of the component parts 142, 142 and passes through a central opening (unlabelled) in the impeller hub 102. (Vane 106 of a similar modular construction and cage 108 are not shown in this view.) In this embodiment, within the delivery sheath, in order of delivery are shown, vane component 142, vane component 144, and impeller hub 102.

[0084] Referring to Figs. 11 and 12, the sequences of securing component parts 142, 144 together (via manipulation of the guidewire 132) to form vane 104 is shown.

[0085] Referring to Fig. 13, there is shown a device 200 being a third embodiment of the present technology. In this embodiment a drive shaft 238 operatively couples the motor (not shown) to the impeller hub 202 to drive the impeller 201. [0086] Modifications and improvements to the above-described implementations of the present technology may become apparent to those skilled in the art. The foregoing description is intended to be exemplary rather than limiting. The scope of the present technology is therefore intended to be limited solely by the scope of the appended claims.

Claims

1. A device for assisting a flow of a fluid within a conduit of an animal body, the device comprising: an impeller hub, the impeller hub structured to be connectable to an impeller vane, the impeller hub being sized, shaped and dimensioned to be implanted into the conduit of the animal body via transcatheter manipulation; at least one impeller vane, the at least one impeller vane structured to be connectable to the impeller hub, the impeller vane being sized, shaped and dimensioned to be implanted into the animal body via transcatheter manipulation; the impeller hub and the at least one impeller vane, when interconnected, forming an impeller, the impeller being sized, shaped and dimensioned to be operable within the conduit of the animal body; a motor having an output shaft operatively connectable to the impeller hub to operate the impeller.

2. The device of claim 1 , wherein the device is unassembled and is assemblable in the conduit of the animal body.

3. The device of any one of claims 1 and 2, wherein, the at least one impeller vane is two impeller vanes, and the impeller hub and the impeller vanes, when interconnected, form the impeller.

4. The device of any one of claims 1 to 3, further comprising a cage for surrounding the impeller, the cage having a collapsed configuration and an expanded configuration, when in the collapsed configuration the cage being sized and dimensioned to be implanted into the animal body via transcatheter manipulation, when in the expanded configuration the cage being sized, shaped and dimensioned to surround the impeller without interfering with operation of the impeller.

5. The device of claim 4, wherein the expanded configuration of the cage is sized, shaped and dimensioned to anchor the device to a wall of the conduit of the animal body.

6. The device of any one of claims 4 to 5, wherein the cage comprises nitinol.

7. The device of any one of claims 1 to 6, wherein the motor is sized, shaped and dimensioned to be implanted into the animal body via transcatheter manipulation.

8. The device of any one of claims 1 to 7, wherein the device further comprises a driveshaft operatively connectable between the output shaft of the motor and the impeller hub to operate the impeller.

9. The device of claim 8, wherein the driveshaft is housed within an elongated housing.

10. The device of claim 9, wherein the elongated housing and the driveshaft are flexible.

11. The device of any one of claims 1 to 10, wherein the impeller hub and the at least one impeller vane are mechanically interlockable with one another.

12. The device of any one of claims 1 to 11, wherein the impeller hub and the at least one impeller vane are slidably interconnectable with one another.

13. The device of any one of claims 1 to 12, further comprising a guide releasably attached to the at least one impeller vane.

14. The device of claim 13, wherein the guide is a guidewire.

15. The device of claim 13, wherein the guide is a catheter.

16. The device of any one of claims 13 to 15, further comprising a delivery sheath containing at least the guide, the impeller hub, and the at least one impeller vane; the delivery sheath and its contents being insertable into a catheter for transcatheter implantation of the contents into the conduit of the animal body.

17. The device of claim 16, wherein the at least one impeller vane comprises a plurality of impeller vane components connectable together to form the at least one impeller vane.

18. The device of claim 17, wherein the guide is releasably attached to the impeller vane components.

19. The device of any one of claims 13 to 18, wherein the guide passes through an opening in the impeller hub.

20. The device of any one of claims 3 and claims 4 to 12 as they depend directly or indirectly from claim 3, further comprising a first guide releasably attached to a first one of the impeller vanes; and a second guide releasably attached to a second one of the impeller vanes.

21. The device of claim 20, wherein one of the first guide and the second guide is a gui dewire.

22. The device of claim 20, wherein one of the first guide and the second guide is a catheter.

23. The device of any one of claims 20 to 22, further comprising a delivery sheath containing at least the first guide, the second guide, the impeller hub, and the impeller vanes; the delivery sheath and its contents being insertable into a catheter for transcatheter implantation of the contents into the conduit of the animal body.

24. The device of claim 23, wherein the first one of the impeller vanes comprises a first plurality of impeller vane components connectable together to form the first one of the impeller vanes, and the first guide is attached to the first plurality of impeller vane components; and the second one of the impeller vanes comprises a second plurality of impeller vane components connectable together to form the second one of the impeller vanes, and the second guide is attached to second plurality of impeller vane components.

25. The device of any one of claims 20 to 24, wherein the first guide passes through an opening in the impeller hub; and the second guide passes through the opening in the impeller hub.

26. The device of any one of claims 4 and claims 5 to 12 as they depend directly or indirectly from claim 3, further comprising a guide releasably attached to the at least one impeller vane and the cage.

27. The device of claim 26, wherein the guide is a guidewire.

28. The device of claim 26, wherein the guide is a catheter.

29. The device of any one of claims 26 to 28, further comprising a delivery sheath containing the guide, the impeller hub, the at least one impeller vane, and the cage; the delivery sheath and its contents being insertable into a catheter for transcatheter implantation of the contents in the conduit of the animal body.

30. The device of claim 29, wherein the at least one impeller vane comprises a plurality of impeller vane components connectable together to form the at least one impeller vane, and the guide is releasably attached to the impeller vane components.

31. The device of any one of claims 26 to 30, wherein the guide passes through an opening in the impeller hub.

32. The device of any one of claims 1 to 31 wherein the animal body is a human body.

33. The device of any one of claims 1 to 32, wherein the at least one impeller vane is between 3 and 10 impeller vanes inclusive.

34. A method of implanting the device for assisting a flow of a fluid within a conduit of an animal body of any one of claims 13 to 25, comprising: inserting the delivery sheath of the device into a desired implant location using a Seldinger technique; delivering the contents of the delivery sheath in place; and manipulating at least one guide to operatively connect the at least one impeller vane to the impeller hub.

35. The method of claim 34, wherein the contents are arranged in the delivery sheath such that at least one impeller vane is delivered prior to the impeller hub.

36. The method of any one of claims 34 to 35, further comprising, prior to manipulating at least one guide to operatively connect the at least one impeller vane to the impeller hub, manipulating at least one guide to connect the plurality of impeller vane components together to form the at least one impeller vane.

37. The method of any one of claims 34 to 36, further comprising manipulating at least one guide to cause the cage to adopt the expanded configuration and to surround the impeller.

38. The method of any one of claims 34 to 37, further comprising operatively connecting the output shaft of the motor to the impeller hub.

39. The method of any one of claims 34 to 38, further comprising operatively connecting the driveshaft to the output shaft of the motor and to the impeller hub.

40. The method of any one of claims 33 to 39, further comprising detaching and removing at least one of the guides.

41. The method of any one of claims 33 to 40, further comprising removing the delivery sheath