Blood pump and associated components and method of use and associated method of manufacture

Abstract

A blood pump having a configuration including a multi-lumen shaft that includes a torque cable mounted at a first end portion to a motor shaft that is part of an extracorporeal pump motor and mounted at an axially spaced second end portion to an in vivo impeller and having a central lumen. The multi-lumen shaft includes a torque cable lumen sized and configured to enclose the torque cable, at least one inflow lumen, and at least one outflow lumen.

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This patent application claims priority and the benefit of priority from U.S. Provisional Application No. 63 / 374,426, filed on September 2, 2022; U.S. Provisional Application No. 63 / 352,907, filed on June 16, 2022; U.S. Provisional Application No. 63 / 352,932, filed on June 16, 2022; U.S. Provisional Application No. 63 / 352,962, filed on June 16, 2022; and U.S. Provisional Application No. 63 / 353,353, filed on June 17, 2022, the contents of which are hereby incorporated by reference as if fully set forth herein.

[0002] The present invention is related to blood pumps and is particularly suitable for intravascular blood pumps such as heart blood pumps.

Background Art

[0003] Over the years, various types of blood pumps have been developed for the purpose of enhancing or replacing the blood - pumping function of damaged or diseased hearts. The pump can be designed to provide right - ventricular and / or left - ventricular assistance, but left - ventricular assistance is a more commonly seen application in that the left ventricle is much more likely to become diseased or damaged than the right ventricle.

[0004] The blood pump must feed the fluid at an appropriate rate without applying excessive Reynolds shear stress to the fluid. It is well known to those skilled in the art that the application of shear stress to cell membranes can cause lysis or cell destruction. Since the cell membrane of red blood cells does not contain a reinforcing cytoskeleton to maintain cell shape, red blood cells are particularly susceptible to shear - stress damage.

[0005] Intravascular blood pumps include small blood pumps that can be introduced percutaneously or surgically into a patient's vascular system and generally provide left heart and / or right heart support. For example, refer to Patent Document 1 that describes a multi-stage intravascular axial flow blood pump that can be percutaneously inserted into an artery for heart assistance, and Patent Document 2 that describes a single-stage intravascular axial flow blood pump. These contents are hereby incorporated by reference as if fully set forth herein. These blood pumps place the drive unit / motor outside the body (extracorporeally) and use a long cable drive system. The operability and / or durability of these types of blood pumps have often been lower than desired. During use, the components of these devices tend to deteriorate prematurely due to the rotational and pulsatile forces received by the blood pump.

[0006] Other intravascular blood pumps are configured such that the drive unit / motor and the impeller are directly connected to each other and the motor and the impeller (pump) housing have substantially the same outer diameter. For example, refer to Patent Document 3. Its content is hereby incorporated by reference as if fully set forth herein. These systems have been well used for blood delivery, but the flow rate provided generally falls below 3 - 4 liters per minute at a backpressure of about 100 mmHg. The low torque limit of small "micro" motors limits the delivery rate.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0008] There is a need for a blood pump that can mitigate the above drawbacks of prior art intravascular blood pumps.

Means for Solving the Problem

[0009] An embodiment of the present invention provides a blood pump comprising an extracorporeal motor, and a multi-lumen shaft that is coupled to the motor at one end and is coupled to an impeller shaft separately, and that surrounds a long torque cable by providing an inflow fluid path and an outflow (purge) fluid path for cooling and / or lubricating the long torque cable.

[0010] The distal end portion of the multi-lumen shaft may be in fluid communication with a bearing housing and a bearing / bushing that is held by the bearing housing and is configured to connect the inflow and outflow fluid paths by providing a transverse fluid purge path.

[0011] Aspects of the present invention relate to lubrication / purge fluid paths.

[0012] Embodiments of the invention relate to a blood pump including an extracorporeal motor housing with a motor coupled to a motor shaft, a torque cable coupled to the motor shaft and extending longitudinally outside the motor housing, and a multi-lumen shaft sized and configured to enclose at least one section of the torque cable and having a torque cable lumen. The torque cable lumen defines at least a portion of an outflow (purge) fluid path that extends around the torque cable along its length. The multi-lumen shaft further includes at least one fluid inflow lumen in fluid communication with the outflow (purge) fluid path such that the outflow fluid of the outflow path purges debris and cools and / or lubricates the torque cable. The blood pump also includes an impeller shaft attached to the distal end portion of the torque cable. The impeller shaft has an outer surface configured to provide a portion of the outflow (purge) fluid path, and the outer surface is configured to be in fluid communication with the distal end portion of the torque cable lumen. The blood pump also includes an impeller coupled to the impeller shaft.

[0013] The torque cable lumen may terminate at a certain distance in the proximal direction from the distal end of at least one inflow lumen of the multi-lumen shaft. The proximal end portion of the impeller shaft may be adjacent to and / or located inside the distal end portion of the torque cable lumen.

[0014] The motor shaft may have an axially extending conduit sized and configured to receive a portion of the torque cable.

[0015] The blood pump may further include a motor cap coupled to the motor and a manifold coupled to the distal portion of the motor cap. The motor cap may have a fluid outflow port in fluid communication with the torque cable lumen.

[0016] The blood pump may further include a manifold surrounding and coupled to a partial length of the multi-lumen shaft. The manifold may have a fluid inflow port in fluid communication with at least one inflow lumen.

[0017] The manifold may be defined by a plurality of cooperating components that are mounted together. The manifold may be mounted to the proximal end portion of the multi-lumen shaft.

[0018] The multi-lumen shaft may include a proximal end portion located in the manifold. The proximal end portion of the multi-lumen shaft may have an outer wall portion provided with a fluid suction port in fluid communication with at least one inflow lumen. The blood pump may further include a fluid inflow conduit mounted to the manifold at one end and to an inflow fluid source connector at the opposite end.

[0019] The blood pump may further include a motor cap surrounding inner and outer seals sandwiching a grease pocket. The motor cap may be coupled to the distal end of the motor, in fluid communication with the fluid outflow path of the multi-lumen shaft, and define a fluid outflow port that provides a portion of the fluid outflow path that extends laterally outward from the motor cap and is external to the inner and outer seals.

[0020] The multi-lumen shaft can be an extruded body having an outer wall portion of a first polymer, optionally a polyamide or a polyimide.

[0021] The extruded body can surround a first internal polymer tube that provides a torque cable lumen, optionally Pebax (PEBAX).

[0022] The snorkel tube can be an extruded body that encloses a coil of a certain length.

[0023] The motor shaft rotates at about 50,000 rpm and has a maximum outer diameter of 0.100 inches, so that in order to make the life of the seal at the distal end portion of the motor as desired, when the shaft is rotating at about 50,000 rpm, it can be configured to reduce the surface speed compared to those of larger diameters.

[0024] The blood pump can further include an outlet cage surrounding the impeller and an inlet cage distal to the outlet cage.

[0025] The blood pump can further include an impeller shaft extending distally from the bearing housing. The impeller shaft can be coupled to the distal end portion of the torque cable.

[0026] Optionally, the impeller shaft can extend into a portion of the proximal bushing. By mounting both the proximal end portion of the impeller shaft and the proximal bushing to the torque cable, the torque cable can be coupled to the impeller shaft.

[0027] The blood pump can further include a bearing housing that holds a bearing / bushing surrounding a portion of the impeller shaft. The bearing / bushing can have at least one radially extending open conduit that defines a transverse portion for allowing purge fluid to cross from at least one inflow lumen, which is in fluid communication with a fluid inflow path provided by at least one inflow lumen of the multi-lumen shaft, to an outflow (purge) fluid path, so that the bearing / bushing acts as a hydrostatic bearing / bushing.

[0028] The blood pump may further include axially spaced proximal and distal bushes located at the end portions on both sides of the bearing / bush. The proximal bush may be mounted on the impeller shaft and the torque cable. Optionally, the distal bush may be mounted on the impeller shaft distally of the bearing housing.

[0029] The proximal and distal bushes may be configured to define thrust washers, thereby securing the bearing / bush therebetween. The proximal and distal bushes may restrain the impeller shaft inside the bearing / bush while the impeller shaft is freely spinning in the bearing / bush.

[0030] The multi-lumen shaft may have at least one pressure sensor lumen.

[0031] The torque cable may have an axially extending lumen. The axially extending lumen of the torque cable can hold at least one section of at least one support wire.

[0032] The torque cable may have a body of a plurality of filament overlapping layers arranged in an overlapping pattern to define a cylindrical body.

[0033] The bearing housing may hold a tube section forming at least one inflow lumen of the multi-lumen shaft and may have a transverse passage that fluidly connects the fluid from the tube section to the bearing / bush beyond the bearing housing in at least one radially extending open conduit.

[0034] Embodiments of the invention provide a blood pump comprising a manifold coupled to a multi-lumen shaft at a proximal end portion and a bearing housing adjacent a distal end portion of the multi-lumen shaft proximate to an impeller of the blood pump, wherein the multi-lumen shaft has an inflow fluid path and an outflow fluid path, the outflow fluid path extending along and surrounding a torque cable retained within the multi-lumen shaft, while the torque cable is coupled to an external motor, flowing a biocompatible fluid into the manifold and then into the inflow path of the multi-lumen shaft, flowing the biocompatible fluid from the inflow path into a transverse path at least partially defined by a bearing (bushing) surrounding a portion of the impeller shaft, and purging debris, cooling, and lubricating the torque cable by flowing the biocompatible fluid out along and around the torque cable from the outflow path, and pumping blood using the blood pump while flowing the biocompatible fluid in and out, related to a method for cooling / lubricating a torque cable of an intravascular blood pump.

[0035] Outflow further includes guiding a portion of the biocompatible fluid from the transverse path to flow along a purge path formed in an impeller shaft coupled to the impeller, while guiding other biocompatible fluid to continue the outflow around the torque cable of the outflow fluid path.

[0036] Outflow further includes guiding a portion of the biocompatible fluid from the transverse path to the patient's body from the impeller shaft / bearing housing interface, while guiding other biocompatible fluid to continue the outflow around the torque cable of the outflow fluid path.

[0037] A portion of the outflow path may be defined by a torque cable lumen of the multi-lumen shaft, and the torque cable lumen may extend longitudinally.

[0038] Aspects of the invention relate to a bearing (bushing) for a heart pump.

[0039] Embodiments of the invention relate to a bearing (bushing) for a heart pump, including a bearing (bushing) body having an axially extending open conduit sized and configured to receive an intravascular impeller shaft. The bearing (bushing) body further defines a fluid cross-flow path sized and configured to define at least one purge fluid path section by including at least one radially extending open conduit, such that the bearing (bushing) acts as a hydrodynamic bearing / bushing.

[0040] The bearing (bushing) body is formed of 3016 PEEK with 15 - 25% by volume of carbon fiber in the range of 15 - 25% by volume and PTFE in the range of 15 - 25% by volume, thereby obtaining a wear-resistant and lubricious body.

[0041] The at least one radially extending open conduit may have first and second radially extending conduit sections facing each other in the axially extending open conduit.

[0042] The at least one radially extending open conduit may have a diameter in the range of about 0.010 inches to about 0.030 inches.

[0043] The axially extending open conduit may have a diameter in the range of about 0.5 mm to about 1 mm.

[0044] The bearing (bushing) may be combined with an impeller shaft having at least one outer surface section with a recess defining part of the fluid purge flow path.

[0045] Aspects of the invention relate to an impeller shaft for a heart pump.

[0046] Embodiments of the invention relate to an impeller shaft sized and configured for an intravascular impeller of a blood pump. The impeller shaft may include a shaft body extending axially. The shaft body may have a proximal end portion and an opposite distal end portion spaced apart. The shaft body may have a maximum outer diameter in the range of 0.5 to 1 mm. The shaft body may have an outer surface with at least one recess defining a purge fluid passageway by extending over at least a portion of the length of the shaft body.

[0047] The at least one recess may define a flat section on the outer surface.

[0048] The at least one recess may be a single recess.

[0049] The at least one recess may be a spiral groove.

[0050] The flat section may extend circumferentially around the outer surface by a distance in the range of 0.010 mm to 0.025 mm.

[0051] The distal end portion may be tapered distally from a maximum outer diameter portion to a smaller diameter portion. The at least one recess may extend proximally on the distal end portion.

[0052] The impeller shaft may have a length in the range of about 10 mm to about 15 mm. The at least one recess may extend for a distance that is at least 50% of the length of the shaft body from the proximal end of the shaft body to a location near the distal end of the shaft body.

[0053] The at least one recess may have a distal end terminating at a distance in the range of 5 to 6 mm from the tip of the distal end portion of the impeller shaft.

[0054] The shaft body may be a metal having a hardness of at least Rockwell C60.

[0055] The outer surface of the shaft body may have a finish of RMS 8.

[0056] The impeller shaft may further include a diamond-like coating (DLC) configured to impart hardness and lubricity.

[0057] Aspects of the present invention relate to an impeller torque cable assembly for a heart pump.

[0058] Embodiments of the invention relate to an impeller subassembly for a blood pump, comprising an impeller sized and configured for intravascular deployment, an impeller shaft attached to the impeller, a distal bushing disposed to surround and attached to an outer surface of a portion of the impeller shaft and attached to the wall of a conduit housing the impeller, a proximal bushing disposed to surround and attached to an outer surface of a portion of the impeller shaft at a location proximal to the distal bushing, a bearing (bushing) surrounding a section of the impeller shaft and located between the distal and proximal bushings, and a torque cable held inside the proximal bushing and attached to the proximal bushing at a location spaced from the impeller shaft.

[0059] The subassembly may further include a bearing housing surrounding the bearing (bushing).

[0060] The bearing (bushing) may have at least one radially extending open conduit defining a cross-section for purging fluid from an upstream fluid inlet path of the bearing / bushing to a purge fluid outlet path in fluid communication with the fluid inlet path, whereby the bearing / bushing also acts as a hydrodynamic bearing / bushing.

[0061] The proximal bushing may be attached to the impeller shaft and to the torque cable and a support wire.

[0062] The proximal and distal bushes may be configured to define a thrust washer, thereby securing a bearing / bush therebetween. The proximal and distal bushes can restrain the impeller shaft inside the bearing / bush while the impeller shaft is freely spinning in the bearing / bush.

[0063] The bearing housing may have an outer surface facing the impeller, where an impeller / housing interface can be defined. The impeller / bearing housing interface may be configured to discharge purge fluid to the impeller.

[0064] The torque cable may have a central conduit that holds a support wire. The proximal bush may be crimped to the distal end portion of the torque cable and the support wire at a first location and may be crimped to the impeller shaft at a second location distal to the first location.

[0065] The torque cable and the support wire may be held in the central lumen of a multi-lumen shaft. The subassembly may further include a bearing housing adapter that extends around the outer distal end of the multi-lumen shaft between the bearing housing and the multi-lumen shaft to attach the multi-lumen shaft to the bearing housing.

[0066] The bearing (bush) may have a radially extending through conduit that defines a direct communication passage sized and configured to connect at least one inlet lumen of the multi-lumen shaft to an outflow path provided by a longitudinally extending conduit of the bearing (bush) in fluid communication with an outflow lumen of the multi-lumen shaft.

[0067] The impeller shaft may have an outer surface held in a conduit of the impeller that defines at least one recess configured to provide a purge fluid passage from purge fluid exiting a bearing housing surrounding the bearing (bush).

[0068] The bearing housing may have an open central conduit and at least one longitudinally extending conduit in fluid communication with at least one radially extending open conduit of the bearing (bushing) located radially spaced from the open central conduit.

[0069] At least one radially extending open conduit of the bearing housing may be arranged as a first conduit, and the bearing housing may have first and second radially extending conduit sections facing each other across the axially extending open central conduit.

[0070] The bearing housing may have an outer surface that faces the impeller and defines a bearing / impeller interface. A first quantity of purge fluid may be configured to exit the bearing / impeller interface while maintaining a sufficient fluid pressure to prevent blood from entering the bearing housing, while a greater second quantity of purge fluid is redirected to an outflow path provided by the outflow lumen of the multi-lumen shaft.

[0071] The multi-lumen shaft may have a central lumen that extends longitudinally and defines at least a portion of the outflow path. The multi-lumen shaft may have at least one inflow lumen that defines at least a portion of the inflow path.

[0072] At least one inflow lumen may extend circumferentially around the central lumen.

[0073] At least one inflow lumen may be provided by first and second polymer tubes at least partially retained in the extruded body of the multi-lumen shaft.

[0074] Aspects of the present invention relate to a motor assembly with a seal for a blood pump.

[0075] Embodiments of the invention relate to a motor assembly for a blood pump, including a motor housing, a motor within the motor housing, a motor shaft coupled to the motor, a torque cable coupled to the motor shaft, and inner and outer seals coupled together to sandwich a grease pocket. The motor shaft that houses the torque cable may extend through the inner and outer seals. The torque cable may be sized and configured to be disposed at a distance outside the outer side of the motor shaft and the outer side of the motor housing.

[0076] The inner seal may be configured as a memory lip seal, and the outer seal may be configured as a cooperating stainless steel spring that applies pressure to the torque shaft. The grease pocket may contain food-grade grease.

[0077] The motor may include a motor end cap that defines a fluid outflow port in fluid communication with a fluid outflow path of a multi-lumen shaft that surrounds the torque cable and extends laterally outwardly from the motor cap to the fluid outflow port outside the inner and outer seals.

[0078] The motor assembly may further include a manifold coupled to the motor end cap. The multi-lumen shaft may extend into the manifold, and the manifold may include an inflow port in fluid communication with at least one inflow lumen provided by the multi-lumen shaft.

[0079] Aspects of the invention relate to a motor shaft for a blood pump.

[0080] Embodiments of the invention relate to a motor shaft for a blood pump, including a cylindrical metal body having an open central conduit sized and configured to receive a flexible torque cable. The cylindrical body may have a maximum outer diameter in the range of 0.050 inches to 0.100 inches and may have an outer surface having a diamond-like coating (DLC) that imparts hardness and lubricity.

[0081] Aspects of the present invention relate to support wires and torque cables for a blood pump.

[0082] Embodiments of the invention relate to a blood pump including an extracorporeal motor housing having a motor coupled to a motor shaft. The motor shaft may have an axially extending conduit. The blood pump may further include a torque cable coupled to the motor shaft and extending longitudinally a certain distance outside the blood pump housing, and a multi-lumen shaft sized and configured to enclose a section of the torque cable and defining at least a portion of a purge fluid outflow path. The multi-lumen shaft may further include at least one inflow lumen. The blood pump may further include an impeller coupled to the distal end of the torque cable and a support wire extending into at least a section of the axially extending conduit of the torque cable.

[0083] The support wire may extend to the motor shaft and extend proximally to terminate at and / or extend from the proximal end of the torque cable.

[0084] The torque cable may extend over the entire length of the motor shaft.

[0085] The torque cable may be configured to float inside the torque cable lumen over at least a majority of its length.

[0086] The support wire may terminate at a distance in the range of 1 to 3 inches in the distal direction of a manifold coupled to the motor. The manifold may define a portion of a fluid inflow path in fluid communication with at least one inflow lumen.

[0087] The support wire may be a first support wire. The blood pump may further include a second support wire extending into the torque cable in the distal direction of the first support wire.

[0088] The first support wire and the second support wire may be nitinol support wires.

[0089] The torque cable may have a body of a plurality of filament superposed layers disposed in a superposed pattern defining a cylindrical body, and a longitudinally extending lumen is disposed in the center so as to extend therein.

[0090] Threads of different layers may be provided at one or more different angles so that the threads of the first layer cross the threads of one or more adjacent layers.

[0091] The blood pump may further include a motor cap coupled to the motor and a manifold coupled to the motor cap. The motor cap may have a fluid outflow port in fluid communication with the outflow path.

[0092] The blood pump may further include a manifold coupled to the motor cap and may include a fluid inflow port in fluid communication with at least one inflow lumen. The manifold may surround a partial length of the multi-lumen shaft.

[0093] The manifold may be defined by a plurality of cooperating components mounted to the proximal end portion of the multi-lumen shaft.

[0094] The multi-lumen shaft may have a proximal end portion located in the manifold. The proximal end portion of the multi-lumen shaft may have an outer wall portion provided with a fluid suction port in fluid communication with at least one inflow lumen. The blood pump may further include a fluid inflow conduit mounted to the manifold at one end and to a fluid inflow connector at the opposite end.

[0095] The blood pump may further include a motor cap surrounding inner and outer seals sandwiching a grease pocket. The motor cap may define an end cap of the motor housing and may provide a fluid outflow port in fluid communication with the fluid outflow path of the multi-lumen shaft. The motor cap may define a part of the outflow path of the blood pump that is outside the inner and outer seals and extends laterally outward from the motor cap.

[0096] The multi-lumen shaft can have an extruded body with an outer wall portion of a first polymer, optionally a polyamide or a polyimide.

[0097] The extruded body can be provided with a first internal polymer tube defining a torque cable lumen, optionally surrounding Pebax and capable of providing at least one inflow lumen, or the extruded body can be provided by a first extruded body defining a torque cable lumen and a cooperating second extruded body disposed coaxially therewith and defining an inflow lumen.

[0098] By rotating at about 50,000 rpm and having a maximum outer diameter of 0.100 inches over at least most of its length, the shaft can be configured to reduce the surface speed for larger diameters when the shaft is rotating at about 50,000 rpm, so as to make the life of the seal at the distal end portion of the motor shaft as desired.

[0099] The blood pump can further include an outflow cage surrounding the impeller and an inlet cage distal to the outlet cage.

[0100] The multi-lumen shaft can have a distal end portion that terminates at a location proximal to and spaced from the impeller.

[0101] The blood pump can further include an impeller shaft extending distally from the bearing housing.

[0102] The blood pump can further include an impeller shaft having at least one outer surface section defining a portion of the (purge) outflow fluid path.

[0103] The blood pump may further include a bearing housing that holds a bearing (bush) surrounding a section of the impeller shaft. The bearing (bush) may have at least one radially extending pipe that is in fluid communication with a fluid inlet path that is at least partially provided by at least one inlet lumen of the multi-lumen shaft and defines at least one transverse (purge) fluid path, whereby the bearing (bush) acts as a hydrostatic bearing / bush.

[0104] The blood pump may further include axially spaced proximal and distal bushes located on both sides of the bearing / bush. The proximal bush may be mounted on the impeller shaft, the torque cable, and the second support wire. The distal bush may be mounted on the impeller shaft outside the bearing housing.

[0105] The bearing / bush may be secured therebetween by configuring the proximal and distal bushes to define a thrust washer.

[0106] The multi-lumen shaft may include at least one pressure sensor lumen.

[0107] The blood pump may further include an impeller shaft coupled to the impeller and the torque cable. The impeller shaft may define a portion of a (purge) fluid outlet path that is in fluid communication with a transverse fluid path provided by a bearing / bush surrounding a portion of the impeller shaft.

[0108] The bearing / bush may surround a portion of the impeller shaft coupled to the impeller. The biocompatible purge fluid from at least one inlet lumen may pass through the through-hole of the bearing / bush providing the transverse fluid path, along a portion of the impeller shaft, and along the torque cable lumen in the distal direction to purge debris and / or cool and lubricate the torque cable.

[0109] The bearing housing may have an outer surface that faces the impeller and defines a bearing / impeller interface. A first quantity of purge fluid may be configured to exit the bearing / impeller interface to the patient while maintaining a sufficient fluid pressure to prevent blood from entering the bearing housing, while a greater quantity of purge fluid is configured to exit the blood pump along an outflow path provided by a multi-lumen shaft.

[0110] The blood pump may be configured to pump blood from an outlet cage at a rate in the range of 2 to 7 liters per minute over a continuous intravascular use of at least 6 days while continuously providing a biocompatible fluid to at least one inlet lumen and to the outflow path.

[0111] Aspects of the invention relate to a motor cap for a blood pump.

[0112] Embodiments of the invention relate to a motor cap for a blood pump that includes a motor cap body having a chamber sized and configured to hold inner and outer cooperating seals, a neck portion configured to receive a neck portion of a manifold, and a proximal longitudinally extending wall portion having threads configured to be coupled to a motor. The end cap may have a fluid outflow port.

[0113] The fluid outflow port may extend laterally outwardly from the longitudinally extending wall portion.

[0114] The neck portion may have an open conduit sized and configured to receive a torque cable.

[0115] The chamber may have an inner surface that defines a portion of a purge fluid outflow path of the blood pump from a multi-lumen shaft to the fluid outflow port.

[0116] Aspects of the invention relate to a manifold for a blood pump.

[0117] An embodiment of the invention relates to a manifold for a blood pump, comprising a first member having axially spaced proximal and distal ends and having an outer wall portion with a fluid inlet port extending therein to an open internal manifold chamber, a second member having a neck portion and attached to the proximal end of the first member, the neck portion having an open through-passageway and being sized and configured to be coupled to an end cap of a motor housing, and a third member attached to the distal end of the first member and having an open through-passageway, the open through-passageway of the third member having a diameter larger than that of the open through-passageway of the second member.

[0118] The manifold may further include a multi-lumen lumen surrounding a torque cable having a proximal end portion mounted to the first member and / or the second member inside the manifold, the torque cable extending outside the second member and the multi-lumen shaft extending outside the third member.

[0119] Aspect of the present invention relates to a method of assembling and manufacturing a blood pump.

[0120] An embodiment of the invention relates to a method of assembling and / or manufacturing a blood pump, including providing a multi-lumen shaft having a torque cable lumen and an inflow lumen. The multi-lumen shaft is flexible and elongated and is configured for an intrarterial serpentine path to a patient's heart. The method may further include attaching a proximal end portion of the multi-lumen shaft to the manifold, inserting a proximal end portion of a torque cable, which extends a certain distance outside the multi-lumen shaft, into a motor shaft of a motor before or after the attachment, attaching a proximal bushing to an impeller shaft and a torque cable, and attaching an impeller to the impeller shaft.

[0121] The method may further include inserting a proximal end portion of the torque cable into an end cap along with the motor shaft before inserting the proximal end portion of the torque cable into the motor shaft.

[0122] The method may further include attaching a bearing housing adapter to a bearing housing and an outer wall portion of the multi-lumen shaft.

[0123] The step of attaching the impeller can include attaching the distal bushing to the impeller shaft, inserting the impeller shaft together with the distal bushing into the impeller's conduit, and attaching the distal bushing and the impeller shaft to the impeller.

[0124] The method can further optionally include attaching the bearing / bushing to the bearing housing and inserting the impeller shaft into the bearing / bushing, before attaching the impeller shaft to the impeller.

[0125] Further features, advantages, and details of the present invention will be recognized by those skilled in the art upon reading the figures and detailed description of the preferred embodiments that follow, such description being merely illustrative of the present invention.

[0126] Aspects of the invention described with respect to one embodiment can be incorporated into different embodiments even if not explicitly described for them. That is, all embodiments, and / or features of any one embodiment, can be combined in any manner and / or combination. The applicant reserves the right to modify the claims at the time of the original application or submit new claims as appropriate, including the right to correct the claims at the time of the original application to incorporate other claims or any of their features even if not so claimed in the original application. The above and other objects and / or aspects of the present invention are described in detail in the following specification.

Brief Description of the Drawings

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DETAILED DESCRIPTION OF THE INVENTION

[0128] Now, referring to the accompanying drawings showing embodiments of the invention, the present invention will be described in more detail below. However, this invention can be embodied in many different forms and should not be construed as limited to the embodiments presented herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Throughout, like numbers refer to like elements. In the specification and drawings, the abbreviation "FIG." can be used interchangeably with the words "Fig." and "Figure". Although one embodiment is considered, it will be recognized that the features or operations of one embodiment can be applied to others.

[0129] In the drawings, the thickness of lines, layers, features, components, and / or regions may be exaggerated for clarity, and broken lines (such as those shown in the circuits of a flow diagram) indicate any feature or operation unless otherwise specified. Additionally, the order of operations (or steps) is not limited to the order presented in the claims unless otherwise clearly indicated.

[0130] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the invention. As used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. When used herein, the terms "comprise" and / or "comprising" specify the presence of the stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. When used herein, the phrase "and / or" includes any and all combinations of one or more of the associated listed items.

[0131] Unless defined otherwise, all terms (including technical and scientific terms) used herein shall have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries shall be understood to have a meaning that coincides with the meaning in the context of the specification and the related art, and it will be further understood that they should not be interpreted in an idealized or overly formal sense unless clearly defined as such herein. Well-known functions or structures are not described in detail for the sake of brevity and / or clarity.

[0132] When a feature such as a layer, region, or substrate is referred to as being "on" another feature or element, it will be understood that it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another feature or element, no intervening elements are present. When a feature or element is referred to as being "connected" or "coupled" to another feature or element, it will also be understood that it can be directly connected to the other element or intervening elements may be present. In contrast, when a feature or element is referred to as being "directly connected" or "directly coupled" to another element, no intervening elements are present. Although an embodiment has been described or illustrated, the features so described or illustrated may also apply to other embodiments. The term "about" means that the stated number can vary by up to + / - 20%.

[0133] Referring to FIGS. 1 and 2, an example of a blood pump 10 is shown. The blood pump 10 includes a motor 14, a multi-lumen shaft 30 that surrounds a torque cable 25, an inlet cage 33 (blood suction port), a (snorkel) tube 35 that extends between the inlet cage 33 and an impeller 40, and an outlet cage 44 (fed blood outlet) having a blood outlet window portion 44w. A snorkel 31 can be attached to the snorkel tube 35 and disposed at the distal end portion 10d of the blood pump 10. The snorkel / snorkel tube can be provided in several configurations.

[0134] The blood pump 10 may also have a manifold 110 coupled to the motor 14. The manifold 110 has a manifold chamber 110c. As will be further discussed below with respect to FIG. 3, the manifold 110 can hermetically surround at least a portion of a partial length of the shaft 30, generally at least one section of the proximal end portion 30p of the multi-lumen shaft 30, and define at least a part of a (purge) fluid inflow path to at least one opening / port 130 of the outer wall portion 30w of the multi-lumen shaft 30 and to at least one inflow lumen 133 provided by the multi-lumen shaft 30. The term "in-flow" can be used interchangeably with "inflow" in this specification. The term "out-flow" can be used interchangeably with "outflow" in this specification.

[0135] The blood pump 10 may also have a bearing housing 50 that includes a bearing housing adapter 52 for coupling the outer wall portion 30w of the multi-lumen shaft 30 to the bearing housing 50, adjacent to the impeller 40. As will be discussed below, the bearing housing 50 can be in fluid communication with a radially extending passage 602 of a bearing / bushing 600 and its longitudinal conduit 605 to provide a cross-flow passage 55 that forms part of an outflow path F O thereof.

[0136] The multi-lumen shaft 30 has a proximal end portion 30p adjacent to the motor 14 and an opposite distal end portion 30d having a terminal end adjacent to the impeller 40. The torque cable 25 also has a proximal end portion 25p adjacent to the motor 14 and an opposite distal end portion 25d having a terminal end adjacent to the impeller 40. The torque cable 25 may also be referred to interchangeably as a "drive cable". The torque cable 25 can be directly or indirectly attached to the impeller 40 at the distal end portion 25d of the torque (drive) cable 25 and to the motor 14 at the proximal end portion 25p of the torque (drive) cable 25.

[0137] The motor 14 can be held in the motor housing 16. The motor housing 16 can be provided as a pair of cooperating handle shells 16s. The motor housing 16 can be an extracorporeal housing.

[0138] (Distal to the housing 16) The in-vivo portion of the blood pump 10 is configured to be inserted into the aorta from a remote access point such as an incision below the groin that provides access to the femoral artery. In so doing, the in-vivo portion of the blood pump 10 (the leading snorkel 31) passes through the descending aorta until it reaches the ascending aorta near the heart. The multi-lumen shaft 30 can surround the torque cable 25 and have a length sufficient to dispose the motor 14 outside the body. The proximal end portion 30p of the multi-lumen shaft 30 can be the end portion facing the impeller 40 and the snorkel 31 and can be located outside the body, generally near the patient's groin. FIG. 7 shows an example of the operational configuration of the heart H having the blood suction cage 33 and the snorkel 31 in the left ventricle (LV) of the patient's heart. The impeller 40 and the blood outlet cage 44 are disposed in the aorta above the aortic valve and adjacent to the coronary artery to discharge the pumped blood from the cage window portion 44w into the aorta, while the motor 14 and the motor housing 16 are outside the patient. The arrows indicate the main blood flow to the suction cage 33 and from the outflow cage 44 during operation.

[0139] Briefly, when the proximal end portion of the torque cable 25 is mechanically rotated by the motor shaft 114 of the motor 14, which is generally disposed outside the patient's body, it transmits a rotational force over the length of the multi-lumen shaft 30 to spin the impeller 40 at high speed near the heart.

[0140] The blood pump 10 may be particularly suitable for performing ventricular assistance during surgery or providing temporary bridging support to help the patient overcome a crisis.

[0141] The motor 14 is arranged to drive the torque cable 25 of the multi-lumen shaft 30, and the torque cable drives the impeller 40 / pump unit. The motor 14, which is operated at an external location, may have any desirable dimensions. The multi-lumen shaft 30 is continuously lubricated by a biocompatible (purging) liquid. A portion of this liquid exits from the bearing / impeller shaft interface and thus enters the blood flow. The remaining portion is guided to flow through the outflow path and can be recovered outside the body after passing through the lumen 131 provided in the multi-lumen shaft 30 that holds the drive cable 25.

[0142] The multi-lumen shaft 30 and the impeller 40 can be sized to have a diameter suitable for intravascular use. For example, the size range includes, but is not necessarily limited to, 9 French to 30 French, this range is generally in the range of 14 French to 24 French, and more generally in the range of 18 French to 20 French.

[0143] The blood pump 10 may include first and second support wires 119, 219 that are longitudinally spaced apart and located inside the torque cable 25. Referring to FIG. 1, the first support wire 119 may have a distal end portion 119e that at least partially extends along the motor shaft 114, terminating in the range of 1 to 3 inches from the manifold 110 and shown in FIG. 3 as extending over the entire motor shaft. The second support wire 219 may have a proximal end portion 219e that terminates in the range of 1 to 3 inches from the proximal end of the impeller shaft 140. The first support wire 119 may support the torque cable 25 in the high torque area (at the motor 14) so that the torque cable 25 does not collapse under load. The first support wire 119 may also act as a tension relief when exiting the distal end of the manifold 110. The second support wire 219 may cause the impeller shaft 140 and the torque cable 25 to be crimped together by using the proximal bushing 400 without collapsing the (hollow) torque cable 25. The second support wire 219 may also act as a tension relief.

[0144] In some embodiments, the first and second support wires 119, 219 may be provided as a single support wire rather than separate support wires, and the single support wire may extend substantially the entire length of the torque cable 25, or may be located only at the proximal end portion or only at the distal end portion of the torque cable 25.

[0145] Referring to FIG. 3, an enlarged cross-sectional view of the proximal end portion 10p of the blood pump 10 is shown. The motor 14 has a motor shaft 114 that obtains a through conduit 114c for holding the proximal end portion 25p of the torque cable 25. The torque cable 25 can extend distally from the conduit 114c of the motor shaft 114 to the lumen 131 of the multi-lumen shaft 30. The torque cable 25 can be joined to the inner wall portion 114w of the conduit 114c. The torque cable 25 can extend over at least 50% of the axial extension length of the conduit 114c. The torque cable 25 can extend over the entire conduit 114c and has a length that is greater on the distal outer side of the motor 14 facing the impeller 40 than on the proximal outer side of the motor 14. The motor shaft 114 can be made of metal and can have a diamond-like coating (DLC) on the inner surface and / or outer surface to impart hardness and improved surface finish and lubricity. The outer diameter of the motor shaft 114 is preferably as small as possible to reduce the surface speed that improves the seal life. In some embodiments, the surface speed is about 773 feet per minute when the motor shaft 114 is rotating at about 50,000 rpm. The maximum outer diameter of the motor shaft 114 over at least a majority (50% or more) of its length can be in the range of 0.0100 inches to 0.050 inches, such as about 0.060 inches.

[0146] The lumen 131 that holds the torque cable 25 can also be referred to as the "torque cable lumen". The torque cable lumen 131 can define at least a part of the purge liquid outflow path F indicated by the arrows towards the outflow conduit 231 and the outflow connector 331. O of.

[0147] The blood pump 10 can also include at least one inflow conduit 233 and an inflow connector 333 that are connected to a source of biocompatible fluid in a pressurized state, such as physiological saline or a physiological saline mixture, a medical (biocompatible) lubricant, a glucose solution, or the like. The connectors 331, 333 can be Luer connectors.

[0148] The inflow conduit 233 is shown by the arrows pointing to the distal end portion 30d of the shaft 30 and the distal end portion of the manifold 110 (purge) fluid inflow path F I can be in fluid communication with at least one inflow lumen 133 of the manifold 110 and the multi-lumen shaft 30 that can define at least a portion of I .

[0149] Referring to FIGS. 3 and 15, the motor 14 can include cooperating inner and outer seals 213, 214 that can sandwich a pocket 216 that includes grease 216g therebetween. The torque cable 25 can extend into conduits 220 formed in the pocket 216 and each of the inner and outer seals 213, 214. The grease 216g can be a food-grade grease such as silicone grease.

[0150] The inner and outer seals 213, 214 can each cooperate to prevent or inhibit outflow fluid from entering the motor 14. Each of the inner and outer seals 213, 214 can be formed of a different material. One of the seals 213, 214 can include a high-performance filled UHMWPE material such as UPC25 by BALSEAL of FootHills Ranch, California, USA. UPC25 is a high-temperature resistant filled UHMWPE material designed to perform chemical and temperature cycling applications in the temperature range up to 135 degrees Celsius and is well-suited for rotational and reciprocating motion applications. The other of the seals 213, 214 can include a polyimide-filled PTFE compound such as SP191 by BALSEAL of FootHills Ranch, California, USA. SP191 exhibits low friction and minimal wear in rotational and reciprocating motion sealing applications, is FDA compliant, and has low outgassing properties according to ASTM E595. Refer to Material Data Sheet M-64 (Review 02:08-18-20). The outer seal 214 can include a 316SL stainless steel spring that applies a sealing pressure to the motor shaft 114. The distal / outer seal 214 can be configured as a flange seal and can include the UPC25 material and a 316L SS spring. The inner / proximal seal 213 can be configured as a memory lip seal and can include the SP191 material.

[0151] Referring again to FIG. 3, the manifold 110 may be provided as a three-member body 110b, and the three members are all coupled and optionally joined together. The three members may include a first end cap 112 and an opposite second end cap 115 that is coupled to the tubular (main) body 111. The tubular body 111 may define a chamber 110c that extends around the multi-lumen shaft 30. The tubular main body 111 may have an outer wall portion 110w that includes at least one fluid port 110p that is coupled to an end portion of the conduit 233. The multi-lumen shaft 30 may include an outer wall portion 30w that includes at least one opening 130 that defines an inlet port such that fluid flows from the inlet conduit 233 into the manifold 110, and then into the inlet lumen 133 and longitudinally into the distal end portion 30d of the multi-lumen shaft 30.

[0152] The first end cap 112 may hold the end of the proximal portion of the multi-lumen shaft 30. The tubular body 111 may have an inner wall portion that bites into the outer wall portion 30w of the multi-lumen shaft 30 to hold it. The first end cap 112 may be joined to or otherwise attached to the inner wall portion 111i of the tubular body 111. The second end cap 115 may be joined to or otherwise attached to the opposite end of the tubular body 111. The second end cap 115 has an opening 115a that is sized and configured to extend the multi-lumen shaft 30 from the manifold 110. The second end cap 115 may be joined and / or sealed to the outer wall portion 30w of the multi-lumen shaft 30.

[0153] (Shown as being through the first end cap 112) The manifold 110 may have a neck portion 112n that projects outwardly and is coupled to a motor cap 315 that has chambers that respectively house and are located around the inner and outer seals 213, 214. The motor cap 315 may have a longitudinally projecting neck portion 316 that faces and is coupled to the neck portion 112n of the first end cap 112. The motor cap 315 may be screwed onto the threads 14t of the distal end portion 14d of the motor 14.

[0154] Outlet path F O At least one port 315p coupled to conduit 231 to define a portion of can be provided in motor cap 315. Motor cap 315 extends longitudinally along short conduit 319 that holds torque cable 25 through internal fluid interface 318 that can extend from manifold 110 to conduit 231, and outlet path F that extends radially at a portion of the diameter of motor cap 315 between the outer surface of outer seal 214 and the inner surface of motor cap 315 O can also define a portion of.

[0155] In some embodiments, torque cable 25 can have an open central conduit 25c that can accommodate support wire 119. Support wire 119 can be nitinol and can have a diameter in the range of 0.010 inches to 0.015 inches and in some particular embodiments about 0.012 inches.

[0156] Referring to FIG. 11, torque cable 25 can be formed of wound filaments 26. Filaments 26 can be wound to form a cylindrical body by a plurality of overlapping layers of filaments disposed as layers, with filaments disposed in an overlapping pattern at different angles in each adjacent layer, and axial extending lumen / conduit 25c disposed to extend centrally. In different layers, one or more respective filaments can be provided at different angles such that filaments of one layer cross filaments of an adjacent layer. Filaments 26 can be thin metal wires such as stainless steel or other suitable material, and the cylindrical body can be flexible enough to elastically bend in at least two dimensions. In some embodiments, a plurality of filaments 26 can be used to define a single strand, and a plurality of strands by filaments 26 are wound or twisted together to form torque cable 25. In some embodiments, eight filaments 26 define each strand, and eight strands are wound together to form torque cable 25. Filaments 26 suitable for torque cable 25 can be obtained from Asahi Intecc USA or Asahi Intecc Global.

[0157] In some embodiments, the torque cable 25 may have an open central conduit 25c along at least a portion of its length. The support wire 119 may float freely within the central conduit 25c or may be attached by friction or adhesion at one or more locations. The support wire 119 may facilitate the assembly of several components and / or may impart tension relief and / or kink prevention support to the flexible torque cable 25 and / or the multi-lumen shaft 30.

[0158] Figure 4A illustrates an example of a multi-lumen shaft 30 having a plurality of internal lumens 131, 133, 135. This figure also shows an (effluent) cage 44, which is not part of the body 30b of the multi-lumen shaft 30. The body 30b of the multi-lumen shaft 30 may be provided as an extruded body 30b comprising a number of (substantially parallel) longitudinally extending lumens 131, 133 and one or more ports 130 extending from an outer wall portion 30w (Figure 3) to the inflow lumen 133. The body 30b may be an extruded body of polyamide or polyimide.

[0159] Provide a lumen 131 for enclosing the torque cable 25 (fluid purge) effluent F O Another tube 131t, such as a Pebax tube, may be used to provide at least a portion of the path. Alternatively, the lumen 131 may be formed directly in the body 30b of the multi-lumen shaft 30. As shown in the figure, at least one inflow lumen 133 may be provided as a pair of radially opposed lumens. At least one inflow lumen 133 may be provided as a plurality of separate tubes or passages formed directly in the multi-lumen shaft body 30b. At least one inflow lumen 133 may be provided as a polymer tube (optionally a polyimide tube) 133t.

[0160] Referring to FIG. 5, at least one inflow lumen 133 can extend a distance "D" in the distal direction from the distal end 131d of the torque cable lumen 131. In other words, the torque cable lumen 131 can terminate at a certain distance in the proximal direction from the distal end of the inflow lumen 133. The distance "D" can be in the range of 10% to 30% of the length of the impeller shaft 140. In some embodiments, the distance D can be in the range of 0.1 mm to 0.3 mm. The impeller shaft 140 can define a part of the transverse F C outflow path F extending between the purge fluid flow paths O . By the impeller shaft 140 and the configurations of the inflow and outflow lumens 133, 131 respectively, structural rigidity / durability can be imparted to the multi-lumen shaft 30.

[0161] The multi-lumen shaft 30 can also include at least one pressure sensor lumen 135 shown as two radially opposed pressure sensor conduits configured to hold (optical) pressure sensors. The at least one pressure sensor lumen 135 is circumferentially spaced from the inflow lumen 133 and can be radially (at a common radius) aligned with the inflow lumen 133. Other pressure sensors and mechanisms can also be used.

[0162] FIG. 4B illustrates another example of an extruded body 30b comprising an inflow lumen 133 provided as an outer ring surrounding an outflow lumen 131 arranged to provide a concentric or coaxial lumen configuration.

[0163] The multi-lumen shaft 30 can be provided by several techniques. For example, the multi-lumen shaft 30 can comprise an extruded body / extrusion body 30b having a number of lumens. The central lumen 131 can be of a different material than the inflow lumen 133. This configuration can be provided by co-extrusion in which separate materials are extruded simultaneously. In other embodiments, such as the coaxial embodiment for Figure 4B, two separate "tube" extruded bodies 30b1, 30b2 of the same or different materials that form coaxial inflow and outflow lumens are provided, but the two extruded tube bodies are coaxially arranged with one surrounding the other and can be assembled together after being extruded separately.

[0164] Refer to FIGS. 5 and 6, which are enlarged cross-sectional views of a portion of the blood pump 10 adjacent to the impeller 40. As shown in the figures, the impeller 40 is mounted on an impeller shaft 140 extending from the distal end portion 30d of the multi-lumen shaft 30. The proximal bushing 400 and the distal bushing 500 can sandwich an intermediate bushing 600 (sometimes referred to as a "bearing", but functionally, since this component does not have a "bearing" or a rotatable component, the term "bushing" may be more accurate). Also, for ease of discussion in terms of the proximal and distal bushings, the terms "bearing / bushing", "bearing (bushing)", or "bushing / bearing" and other such terms 600 can be used interchangeably herein to refer to the component of the bushing 600.

[0165] The bearing / bushing 600 can be formed of a polymer such as PEEK. In some embodiments, the bearing / bushing 600 can be formed of 3016 PEEK containing carbon fiber in the range of 15 - 25 (volume)% and PTFE in the range of 15 - 25 (volume)%, thereby providing a body with wear resistance and lubricity.

[0166] The distal end 25d of the torque cable 25 can be coupled to a proximal bushing 400 that can be mounted on the impeller shaft 140. The distal end portion 140d of the impeller shaft 140 can be inserted into the conduit 41 of the impeller 40. The distal bushing 500 can be crimped onto the impeller shaft 140. The impeller 40 can be press-fitted and / or joined to the impeller shaft 140 and the distal bushing 500. The proximal bushing 400, which can act as a thrust washer, can be provided at the proximal end portion 140p of the impeller shaft 140. The proximal bushing 400 can be mounted, for example, crimped and / or joined, to the impeller shaft 140 and the torque cable 25, and, if used, the second support wire 219. In so doing, the proximal bushing 400 defines a part of an assembly that can be mounted, such as by press-fitting and / or joining, to the bearing housing 50.

[0167] The bearing / bushing 600 can be press-fitted into the bearing housing 50 and no adhesive is required. However, in some embodiments, the bearing / bushing 600 can be joined to the bearing housing 50.

[0168] The distal and proximal bushings 500, 400 can each act as thrust washers that "secure" the bearing / bushing 600. The thrust washer / bushings 400, 500 restrain the impeller shaft 140 inside the bearing / bushing 600 while allowing the impeller shaft 140 to spin freely within the bearing / bushing 600. The distal and proximal bushings 500, 400 maintain a gap that provides an interface 50I between the impeller 40 and the bearing housing, and hold the impeller shaft 140 in a position that provides an outflow path F for purge fluid from the bearing housing at this interface 50I. H The impeller shaft 140 can be held at a position that provides the outflow path F for purge fluid from the bearing housing at this interface 50I.

[0169] In some embodiments, the second support wire 219 can extend along the torque cable 25 in a region adjacent to the impeller shaft 140 and can extend proximally from the proximal end of the impeller shaft 140 in the range of 1 to 3 inches.

[0170] The bearing / bushing 600 can be located in the bearing housing 50. The bearing housing 50 can define an impeller / interface 50I between the outer surface 50f of the bearing housing 50 and the impeller 40. The bearing outer surface 50f facing the proximal end 40p of the impeller 40 is spaced at a distance close to the proximal end 40p of the impeller 40. This distance can be in the range from about 0.001 inches to about 0.015 inches. The bearing housing 50 cooperates with the bearing / bushing 600, the impeller shaft 140, and the multi-lumen shaft 30 to define a purge fluid path P of the interface 50 that guides fluid to exit from the surface 50f radially spaced from the proximal end 40p of the impeller 40. F defines. The pressure / flow rate of the purge fluid P at this impeller / bearing housing interface F is relatively low and can be discharged into the blood, but is sufficient to prevent blood from entering the bearing / bushing 600 and / or the bearing housing 50.

[0171] The bearing housing adapter 52 can attach the outer wall portion 30w of the multi-lumen shaft 30 to the outer wall portion 50w of the bearing housing 50. The bearing housing adapter 52 can be tapered inwardly from the outer diameter portion of the bearing housing 50 in the direction towards the motor 14.

[0172] Referring to FIG. 6, a portion of the proximal bushing 400 and the proximal end of the impeller shaft 140 can be located inside the outflow lumen 131 and / or inside the outflow tube 131t along with the torque cable 25.

[0173] Referring to FIGS. 5, 6, 8A - 8C, 9A - 9C, the bearing housing 50 may have a longitudinally extending central conduit 54 that holds the outer surface of the bearing / bushing 600. The bearing housing 50 may also have first and second longitudinally extending conduits 53 on both sides of the central conduit 54. The first and second conduits 53 are in fluid communication with their respective inlet pipes 133t and / or hold a section thereof. The bearing housing 50 may have a transverse passage 55 that is in fluid communication with the port 602 of the bearing / bushing 600 and the longitudinally extending conduit 605. The transverse passage 55 uses the bearing / bushing 600 to connect the inlet path F provided by the inlet lumen 133 I to the outlet path F provided by the torque cable lumen 131 O in fluid connection. A sealing material 155 (such as an adhesive) may be used to seal the outer end of the passage 55. The transverse passage 55 may be aligned with the port 602 of the bearing / bushing 600.

[0174] The transverse passage 55 may have an outer diameter in the range of from about 0.010 inches to about 0.030 inches, such as about 0.020 inches. In some embodiments, the first and second conduits 53 may have an outer diameter larger than that of the transverse passage 55, generally in the range of from about 0.020 inches to about 0.030 inches, such as about 0.025 inches.

[0175] Examples of the bearing / bushing are shown in FIGS. 10A and 10B. The bearing / bushing 600 has a central conduit 605 sized and configured to receive a section of the impeller shaft 140. The radially extending passage 602 is located near the distal end 600d rather than the proximal end 600p of the bearing / bushing 600. At least one of the radially extending passages 602 may be located at a distance in the range of from about 0.020 inches to about 0.075 inches, such as about 0.050 inches, from the distal end 600d of the bearing / bushing 600 as measured from the center of the radially extending passage 602.

[0176] Referring to FIGS. 5, 6, and 13, the impeller shaft 140 can be configured to have a distal end 140d that is a tapered end 141. The impeller shaft 140 can have at least one outer surface section 145 configured to provide a distal outflow / liquid purge path. The at least one outer surface section 145 can extend for a partial length of the impeller shaft 140 from the proximal end 140p to an intermediate section. The shape / depth / width of the outer surface section 145 can be sized to regulate the volume of purge fluid passing through the shaft / bearing interface 50I. One or more of the shapes / widths of the at least one outer surface section 145 can vary along the length of the impeller shaft 140. For example, a larger flow path configuration can be provided proximal to the shaft / bearing interface 50I in the direction towards the torque cable lumen 131 relative to the size inside the body of the impeller 40.

[0177] The at least one outer surface section 145 can be flat, or have a recess, or other configuration providing a fluid passage / path. FIG. 12C illustrates an outer surface section 145 that can be provided as a helical groove 145'. Thus, the outer surface section 145' can be helical to different circumferential positions over a certain length.

[0178] When the at least one outer surface section 145 is provided as a linear recess and / or a flat recess section, these can be a single outer surface section or multiple outer surface sections, and each such recess section or single section can have a circumferential extent β that ranges up to about 45 degrees, generally in the range of 10 - 30 degrees.

[0179] The impeller shaft 140 can have an overall length L1 in the range of 12 to 15 mm. The distal end portion 140d can be tapered inwardly over a small length L2 in the range of 1 mm or less, such as from 0.1 mm to 0.7 mm. At least one outer surface section 145 can have a longitudinal extent length L3 in the range of 3 to 8 mm, generally 7 to 8 mm, and can start from the proximal end 140p of the impeller shaft 140. At least one outer surface section 145 can extend from the proximal end 140p at least to a position adjacent to the outer surface 50f of the bearing housing 50. The impeller shaft 140 can be made of medical grade hardened steel with a minimum Rockwell of C60. The impeller shaft 140 can be coated with a diamond-like coating (DLC) for hardness and lubricity. In some embodiments, the impeller shaft 140 can have a smooth finish of RMS 8.

[0180] Referring to FIGS. 6, 13, and 17, at least one outer surface section 145 can be configured to provide a discharge outflow path P, indicated by an arrow, for exiting from the proximal side of the impeller 40 at the bearing housing / impeller interface 50I. F The distal outflow of the purge fluid can be "clean" and / or a fluid seal can be provided at the bearing housing / impeller interface 50I so that blood does not enter the bearing / bush 600.

[0181] Optionally, at least one outer surface section 145 can extend inside the body of the impeller 40 to define a small distal outflow path P, indicated by small arrows, extending towards the distal end 40d of the impeller both outside the impeller shaft 140 and inside the impeller 40. I can be defined.

[0182] The blood pump 10 can be configured to provide a purge flow path without the need for a seal at the distal end portion 30d of the multi-lumen shaft 30. Using the transverse passage 55 of the bearing housing 50, the radially extending passage 602 of the bearing / bushing 600, and the central conduit 605, which cooperate to operate without the need for a seal at the distal end portion 30d of the multi-lumen shaft 30 in a fluid communication state, a transverse path F C to, and then an outflow path F O to which an inflow path F I merges can be defined. The blood pump 10 can be configured. The bearing housing 50 can cooperate with the bearing / bushing 600 to define an orthogonal flow section from the inflow lumen 133 to at least one outer surface section 145 of the impeller shaft 140. The radially extending passage 602 can have an outer diameter in the range of 0.010 inches to 0.030 inches, such as about 0.020 inches. The central conduit 605 can have a diameter larger than that of the radially extending passage 602, and the central conduit 605 can be in the range of about 0.020 inches to 0.030 inches, such as about 0.026 inches.

[0183] The impeller 40 can be an extended impeller. For example, reference is made to U.S. Patent No. 9,028,392, U.S. Patent No. 8,079,948, co-pending U.S. Patent Application No. 17 / 858,615, and U.S. Provisional Patent Application No. 63 / 353,353, the contents of which are hereby incorporated by reference as if fully set forth herein.

[0184] Now referring to FIGS. 16 and 17, examples of purge fluid directions that can be provided by the blood pump 10 are an inflow "F I ", an outflow "F O ", a purge fluid "P F " at the impeller / bearing housing interface 50I, and a purge fluid "P I " at the impeller shaft 140 are shown.

[0185] Figure 18 shows an operation that can be performed to cool / lubricate the torque cable of an intravascular blood pump. The blood pump includes a manifold coupled to a multi-lumen shaft at its proximal end portion and a bearing housing at its distal end portion. The bearing housing is proximal to the impeller of the blood pump. The multi-lumen shaft includes an inflow fluid path and an outflow fluid path. The outflow fluid path extends along and surrounds a torque cable held within the multi-lumen shaft, while the torque cable is coupled to an extracorporeal motor (block 500). A biocompatible fluid flows into the manifold and into the inflow path of the multi-lumen shaft (block 510). And the biocompatible fluid from the inflow path flows into a transverse path that is at least partially defined by a bearing (bushing) surrounding a section of the impeller shaft (block 520). And the biocompatible fluid flows out along and around the torque cable from the outflow path, thereby purging debris and cooling and lubricating the torque cable (block 530). The method may also include pumping blood using the blood pump while flowing the biocompatible fluid in and out (block 540).

[0186] The outflow may include guiding a portion of the biocompatible fluid from the transverse path to flow along a purge path formed on the outer surface of the impeller shaft coupled to the impeller, and the remaining volume of the biocompatible fluid proceeds in the outflow fluid path to the outflow portion around the torque cable (block 545).

[0187] The outflow further includes guiding a portion of the biocompatible fluid from the transverse path from the impeller shaft / bearing housing interface to the patient's body (block 550).

[0188] Referring to FIGS. 19A and 19B, the blood pump 10 is configured to include a motor housing 16, and the motor 14 is an extracorporeal type. A power connector 129 can be coupled to the motor housing 16 and the motor 14. The multi-lumen shaft 30 surrounds the torque cable 25 and has a distal end 30d that terminates at the outlet cage 44 and / or the impeller 40. A snorkel tube 35 extends between the inlet cage 33 and the impeller 40 and / or the outlet cage 44 (blood supply outlet). The snorkel 31 can be attached to the snorkel tube 35 and disposed at the distal end 10d of the blood pump 10.

[0189] Referring to FIG. 19B, the snorkel tube 35 can include a coil 135 encapsulated and / or embedded in one or more substrates of the snorkel tube 35. The snorkel tube 35 can be an extruded body with the coil 135 encapsulated therein. The snorkel tube 35 can be an extruded or molded body of a medical polymer and / or copolymer. The coil 135 can be (inside) between at least one layer of the material / substrate forming the snorkel body 35 and can be encapsulated in a lubricious medical elastomeric material. In some embodiments, the snorkel tube 35 can have a higher elasticity than the catheter 30 and / or a lower durometer than the durometer of the catheter 30.

[0190] Coil 135 can be a single coil or a number of coils configured to provide a series of coil segments over at least a majority of the axial length of the snorkel tube 35 as shown over its full length. Coil 135 can have a series of circumferentially extending coil segments 135s that vary in spacing / density at different locations so as to increase the number of adjacent / neighboring coil segments 135s at one or more different locations. As shown in the figure, the distal end 135d of coil 135 can have contacting coil segments 135s and can have a smaller outer diameter relative to at least some of the more proximal coil segments 135s. The distal end 135d of coil 135 can be attached to the proximal end of the inlet cage 33 terminating therewith. Coil 135 can be configured to provide at least a section in a helical 136 configuration. Coil 135 can be configured to have symmetrically spaced coil segments over a portion of its axial distance.

[0191] Again referring to FIG. 19B, the multi-lumen shaft 30 has a maximum outer diameter “d1” that is smaller than the maximum outer diameter “d2” of the snorkel tube 35. In some embodiments, d2 > 1.1d1 and d2 < 2d1.

[0192] Now referring to FIG. 20, as discussed above, the impeller can be the expanded impeller 40’ shown within the patient's heart H. The expanded impeller 40’ has a first configuration for insertion / removal in which the blades 44b are crushed against the shaft 40s and an operating configuration in which the impeller blades 44b project radially from the shaft 40s. As shown in the figure, the expanded impeller 40’ is inside an expandable (or crushable) cage 44’ that includes a blood outflow window 44w. Further details of examples of expanded impellers can be found, for example, in U.S. Patent No. 9,028,392, U.S. Patent No. 8,079,948, co-pending U.S. Patent Application No. 17 / 858,615, and U.S. Provisional Patent Application No. 63 / 353,353, and reference is made thereto, and these contents are incorporated herein by reference as if fully set forth herein.

[0193] Embodiments of the present invention provide a method for assembling and / or manufacturing a blood pump. The method includes providing a multi-lumen shaft having a torque cable lumen and an inflow lumen, the multi-lumen shaft being flexible and elongate and configured for insertion via an intrarterial serpentine path into a patient's heart. The proximal end portion of the multi-lumen shaft is attached to a manifold. The method also includes attaching, either before or after attachment, the proximal end portion of a torque cable that extends a certain distance outside the multi-lumen shaft to a motor shaft of a motor. The method also includes attaching a proximal bushing to the impeller shaft and the torque cable, and attaching a bearing / bushing to the impeller shaft. The method also includes attaching a bearing housing to the bearing / bushing, and attaching an impeller to the impeller shaft.

[0194] The method may include inserting the proximal end portion of the torque cable into an end cap alongside the motor shaft before inserting the proximal end portion of the torque cable into the motor shaft.

[0195] The method may include attaching a bearing housing adapter to the bearing housing and the outer wall portion of the multi-lumen shaft.

[0196] The impeller may be attached by attaching a distal bushing to the impeller shaft, inserting the impeller shaft together with the distal bushing into the conduit of the impeller, and joining the distal bushing and the impeller shaft to the impeller.

[0197] The blood pump 10 can be sized and configured for use at a valve, such as left ventricular and / or right ventricular assist procedures. By way of example only, such ventricular assist procedures can be employed in cardiac surgery including coronary artery bypass grafting (CABG), cardiopulmonary bypass (CPB), open and closed chest (minimally invasive) surgery, implantable assist devices, and / or situations of failure-to-wean-from-bypass, but are not limited thereto. However, it should be readily understood that the intravascular blood pump assembly and method of the present invention are not limited to such uses. Also, although generally illustrated and described with reference to left heart assist applications, it should be readily understood that the principles of the present invention apply equally to right heart assist applications considered to be within the scope of the present invention. The foregoing and other variations and additional features will be described in detail.

[0198] The blood pump 10 has an inflow path F I and, via at least one inflow lumen 133, an outflow path F O and is configured to pump blood from the outlet cage 44 at a rate in the range of 2 to 7 liters per minute over a period of continuous intravascular use of at least 6 days while continuously providing a biocompatible fluid.

[0199] The blood pump 10 can be configured to provide axial or mixed flow. As used herein, the term "axial flow" is considered to include flow characteristics that include both axial and (some) radial components.

[0200] Blood pump 10 is configured to redirect blood through the right ventricle and / or the left ventricle, by providing left heart and / or right heart support, with the goal of reducing the volume of blood pumped by a particular ventricle. “Unloading” the ventricle in this manner is suitable in certain instances, but it should be readily understood that the pump and cannula arrangement described herein may be employed to “preload” the ventricle. Ventricular preload can be achieved by positioning the outflow cannula from the pump into a given ventricle such that the pump can be used to fill the ventricle with blood or preload it. This is particularly beneficial in the right ventricle. Sometimes, when an adequate level of blood is not supplied to the right ventricle from the right atrium, the amount of blood the right ventricle delivers to the pulmonary artery during systole is insufficient. This can result when the right ventricle and / or right atrium are under stress or strain during surgery. Preloading can overcome this problem by actively supplying blood to the right ventricle and facilitating delivery of blood to the pulmonary artery. The same technique can be used to facilitate delivery of blood from the left ventricle to the aorta by preloading the left ventricle.

[0201] The drawings and the specification disclose embodiments of the invention and employ specific terms, but these are for illustrative purposes only and are used in a general and descriptive sense only, and the scope of the invention is set forth in the following claims.

[0202] Accordingly, the foregoing is illustrative of the invention and should not be construed as limiting thereof. More specifically, workflow steps may be performed in different ways, in different orders, and / or in conjunction with other workflow steps, or some workflow steps may be omitted or replaced with other steps. Although only a few exemplary embodiments of the invention have been described, those skilled in the art will readily recognize that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of the invention.

[0203] Accordingly, all such modifications are intended to be included within the scope of the invention as defined in the claims. In the claims, a means-plus-function clause, when used, is intended to cover not only structural equivalents but also equivalent structures for performing the recited function in combination with the structures described in this specification when implemented in use. Therefore, the foregoing is illustrative of the invention and should not be construed as being limited to the specific embodiments disclosed, and it should be understood that modifications to the disclosed embodiments are intended to be included within the scope of the appended claims together with other embodiments. The invention is defined by the following claims, and equivalents of the claims are also included therein.

Explanation of Reference Numerals

[0204] 10 Blood pump 14 Motor 14t Thread 16 Motor housing 16s Handle shell 25 Torque cable 25c Open central pipeline 26 Filament 30 Multilumen shaft 30b Body 31 Snorkel 33 Inlet cage 35 Snorkel tube 40 Impeller 40’ Extended impeller 40s Shaft 41 Pipeline 44 Outlet cage 44’ Extended cage 50 Bearing housing 50f Outer surface 50I Impeller / bearing housing interface 52 Bearing housing adapter 53 First and second pipelines 54 Central pipeline 55 Cross passage 110 Manifold 110b Three-member body 110c Manifold chamber 111 Tubular body 112 First end cap 112n Head portion 114 Motor shaft 115 Second end cap 115a Opening 119 First support wire 129 Power connector 130 Opening 131 Lumen 133 Lumen 135 Coil 135s Coil section 136 Spiral configuration 140 Impeller shaft 141 Tapered end 145 Outer surface section 145’ Spiral groove portion 155 Sealing material 213 Inner seal 214 Outer seal 216 Pocket 216g Grease 219 Second support wire 220 Pipeline 231 Outflow conduit 233 Inflow conduit 315 Motor cap 315p Port 316 Head portion 318 Internal fluid interface 319 Short pipeline 331 Outflow connector 333 Inflow connector 400 Proximal bushing 500 Distal bushing 600 Bearing (bushing) 602 Radially extending passage 605 Central pipeline F C Transverse path F I Inflow path F O Outflow path H Heart L1 Overall length Small length of L2 P F Purge fluid path β Circumferential extension range

Claims

1. An external motor housing equipped with a motor coupled to a motor shaft, A torque cable connected to the motor shaft and extending longitudinally on the outside of the motor housing, A multi-lume shaft comprising a torque cable lumen sized and configured to enclose at least one section of the torque cable, wherein the torque cable lumen further comprises at least one fluid inlet lumen that defines at least a portion of an outflow fluid path extending along and around the torque cable and is in fluid communication with the outflow fluid path, so that the outflow fluid of the outflow fluid path purges debris and cools and / or lubricates the torque cable, An impeller shaft attached to the distal end portion of the torque cable, comprising an outer surface configured to provide a portion of the outflow fluid path, and the outer surface configured to be in fluid communication with the distal end portion of the torque cable lumen, An impeller coupled to the impeller shaft, A blood pump equipped with the following features.

2. The blood pump according to claim 1, wherein the torque cable lumen terminates in the proximal direction at a certain distance from the distal end of at least one fluid inlet lumen of the multi-lumen shaft, and the proximal end portion of the impeller shaft is located adjacent to and / or inside the distal end portion of the torque cable lumen.

3. The blood pump according to claim 1, wherein the motor shaft is provided with an axially extending conduit that is sized and configured to accommodate a portion of the torque cable.

4. The blood pump according to claim 1, further comprising a motor cap coupled to the motor and a manifold coupled to the distal portion of the motor cap, wherein the motor cap is provided with a fluid outlet port that is in fluid communication with the torque cable lumen.

5. The blood pump according to claim 1, further comprising a motor cap that surrounds internal and external seals sandwiching a grease pocket, wherein the motor cap is coupled to the distal end of the motor and defines a fluid outlet port that is in fluid communication with the fluid outlet path of the multi-lumen shaft, and provides a portion of the fluid outlet path that is outside the internal and external seals and extends laterally outward from the motor cap.

6. The present invention further comprises an impeller shaft extending distally from the bearing housing and entering the impeller, wherein the proximal end of the impeller shaft is connected to the distal end portion of the torque cable. The impeller shaft extends over a portion of the proximal bushing, and the torque cable is connected to the impeller shaft by the proximal end portion of the impeller shaft and the proximal bushing being attached to the torque cable. A blood pump according to claim 1.

7. The blood pump according to claim 1, further comprising a bearing housing that holds a bearing surrounding a portion of the impeller shaft, wherein the bearing is in fluid communication with a fluid inflow path provided by at least one inflow lumen of the multi-lumen shaft, defines a transverse portion for allowing purge fluid to traverse from the at least one inflow lumen to the outflow fluid path, and comprises at least one radially extending open conduit through which a portion of the purge fluid from the transverse portion flows between the impeller shaft and the bearing, thereby the bearing acts as a hydrostatic bearing and suppresses contact between the bearing and the impeller shaft.

8. The bearing further comprises proximal and distal bushings located at both ends of the bearing and spaced apart in the axial direction, wherein the proximal bushing is mounted on the impeller shaft and the torque cable, The distal bushing is mounted on the impeller shaft distal to the bearing housing. A blood pump according to claim 7.

9. The blood pump according to claim 8, wherein the proximal and distal bushings are configured to define a thrust bushing, the impeller shaft extends over the proximal and distal bushings and a bearing, the proximal bushing has a distal flange, the distal bushing has a proximal flange, and the bearing is fixed between the distal flange and the proximal flange.

10. The blood pump according to claim 1, wherein the torque cable comprises an axially extending lumen, and the axially extending lumen of the torque cable holds at least one portion of at least one support wire.

11. The blood pump according to claim 7, wherein the bearing housing holds a tubular section forming at least one inlet lumen of the multi-lumen shaft, and comprises a transverse passage for fluid connection of fluid from the tubular section through the bearing housing to the at least one radially extending open conduit in the bearing, and the outer end of the at least one radially extending open conduit is sealed.

12. A method for cooling / lubricating the torque cable of an intravascular blood pump, A blood pump is provided comprising a manifold coupled to a multi-lumen shaft at its proximal end, and a bearing housing adjacent to the distal end of the multi-lumen shaft located proximal to the impeller of the blood pump, wherein the multi-lumen shaft comprises an inflow fluid path and an outflow fluid path, the outflow fluid path extends along and surrounds a torque cable held on the multi-lumen shaft, and the torque cable is coupled to an external motor. The biocompatible fluid is introduced into the manifold and into the inflow path of the multi-lumen shaft, The biocompatible fluid is to flow from the aforementioned inflow path to a transverse path defined at least partially by a bearing surrounding a portion of the impeller shaft connected to the impeller, Furthermore, by discharging the biocompatible fluid from the outflow path along and around the torque cable, any debris is purged, and the torque cable is cooled and lubricated. The blood pump is used to supply blood while the biocompatible fluid is flowing in and out. A method of including.

13. The method of claim 12, wherein the flowing further includes guiding a portion of the biocompatible fluid from the transverse path to flow along the torque cable of the outflow fluid path and around the torque cable, while guiding the other portion of the biocompatible fluid to flow along the torque cable of the outflow fluid path.

14. The method of claim 12, wherein the flow further includes guiding a portion of the biocompatible fluid from the transverse path to the patient's body through the interface between the impeller shaft and the bearing housing interface, while guiding the other biocompatible fluid along the torque cable of the outflow fluid path and outflow around the torque cable.

15. The impeller shaft is a shaft body extending in the axial direction, comprising a proximal end portion and an opposite distal end portion spaced apart, and comprising an outer surface having at least one flat section or recess that defines a purge fluid passage by extending over at least a portion of the length of the shaft body, A blood pump according to claim 1, comprising:

16. The blood pump according to claim 15, wherein the at least one flat section or recess defines a flat section on the outer surface.

17. The blood pump according to claim 15, wherein the at least one flat section or recess is a single recess.

18. The blood pump according to claim 15, wherein the at least one flat section or recess is a spiral groove.

19. The blood pump according to claim 16, wherein the flat section extends circumferentially for a distance of 0.010 mm to 0.025 mm around the outer surface.

20. The blood pump according to claim 15, wherein the impeller shaft has a length in the range of 10 to 15 mm, and the at least one flat section or recess extends for a distance of at least 50% of the length of the shaft body from the proximal end of the shaft body to the proximal part of the distal end.

21. A distal bushing is disposed to surround the outer surface of a portion of the impeller shaft and be mounted on the outer surface, housed in the piping of the impeller and mounted on the wall surface of the piping of the impeller shaft, A proximal bushing is provided that surrounds the outer surface of a portion of the impeller shaft at a proximal position to the distal bushing and is mounted on the outer surface of the distal bushing, The impeller shaft is further provided with a bearing located between the distal and proximal bushings, surrounding one section of the impeller shaft. The blood pump according to claim 1, wherein the distal end portion of the torque cable is held inside the proximal bushing and attached to the proximal bushing at a point spaced apart from the impeller shaft.

22. The blood pump according to claim 21, further comprising a bearing housing surrounding the bearing, wherein the bearing housing is fixed to the outer wall of the catheter body providing the multi-lumen shaft.

23. The blood pump according to claim 21, wherein the proximal and distal bushings are configured to define a thrust bushing, the bearing is held in a bearing housing fixed to the outer wall of the catheter providing the multi-lumen shaft, and the proximal and distal bushings are configured to keep the impeller stationary in the axial direction and prevent axial movement relative to the bearing.

24. The blood pump according to claim 22, wherein the bearing housing has an outer surface facing the impeller, defining an interface on the outer surface, and the interface is configured to discharge purge fluid to the impeller.

25. The blood pump according to claim 21, wherein the torque cable comprises a central conduit for holding at least one support wire, and the proximal bush is crimped at a first location to the torque cable and one distal end portion of the at least one support wire, and crimped at a second location distal to the first location to the impeller shaft.

26. The blood pump according to claim 22, wherein the bearing housing has an outer surface facing the impeller that defines the interface between the bearing and the impeller, and a first amount of purge fluid is configured to exit from the interface between the bearing and the impeller while maintaining sufficient fluid pressure to prevent blood from entering the bearing housing, while a second, larger amount of purge fluid is guided to return to an outflow path provided by the outflow lumen of the multi-lumen shaft.

27. ​​The blood pump further comprises: A blood pump according to claim 1, comprising an inner and outer seal that are joined together and sandwich a grease pocket, wherein the motor shaft, which contains the torque cable, extends within the inner and outer seals, and the torque cable is sized and configured to extend a certain distance outside the motor shaft and outside the motor housing.

28. The blood pump of claim 27, wherein the inner seal is configured as a memory lip seal, the outer seal is configured as a cooperative stainless steel spring that applies pressure to the torque shaft, and the grease pocket contains food-grade grease.

29. The blood pump according to claim 27, wherein the motor comprises a motor end cap that defines a fluid outlet port in fluid communication with the fluid outlet path of a multi-lumen shaft surrounding the torque cable, and provides at least a portion of the fluid outlet path that is outside the internal and external seals and extends laterally outward from the motor cap to the fluid outlet port.

30. The blood pump according to claim 1, wherein the motor shaft comprises a cylindrical metal body having a central conduit sized and configured to accommodate a flexible torque cable when open, the cylindrical body having a maximum outer diameter in the range of 0.050 inches to 0.100 inches, and having an outer surface having a diamond-like coating (DLC) that provides hardness and lubricity.

31. An external motor housing comprising a motor coupled to a motor shaft, wherein the motor shaft comprises an axially extending conduit, A torque cable connected to the motor shaft and extending longitudinally for a certain distance outside the blood pump housing, A multi-lume shaft comprising a torque cable lumen sized and configured to enclose one section of the torque cable and define at least a portion of the purge fluid outflow path, further comprising a multi-lume shaft comprising at least one inflow lumen, An impeller connected to the distal end of the torque cable, At least one support wire extending over at least one section of the axially extending conduit of the torque cable, A blood pump equipped with the following features.

32. The blood pump according to claim 31, wherein the at least one support wire extends along the motor shaft and terminates at the proximal end of the torque cable, and / or extends proximal to extend from the proximal end.

33. The blood pump according to claim 31, wherein the torque cable extends over the entire length of the motor shaft.

34. The blood pump according to claim 31, wherein the at least one support wire terminates distally to the manifold coupled to the motor, and the manifold defines a portion of a fluid inflow path that is in fluid communication with the at least one inflow lumen.

35. The blood pump according to claim 31, wherein the at least one support wire is provided as a first support wire and a second support wire, and the second support wire is configured to extend to the torque cable distal to the first support wire.

36. The blood pump according to claim 31, further comprising a motor cap coupled to the motor and a manifold coupled to the motor cap, wherein the motor cap has a fluid outlet port that is in fluid communication with the outlet path.

37. The blood pump according to claim 36, further comprising a manifold coupled to the motor cap and having a fluid inlet port in fluid communication with the at least one inlet lumen, wherein the manifold surrounds a portion of the length of the multi-lumen shaft.

38. The blood pump according to claim 37, wherein the multi-lumen shaft comprises a proximal end portion located in the manifold, the proximal end portion of the multi-lumen shaft comprises an outer wall portion having a fluid intake port in fluid communication with at least one inlet lumen, and further comprises a fluid inlet conduit attached to the manifold at one end and to a fluid inlet connector at the other end.

39. The blood pump according to claim 31, further comprising a motor cap that surrounds internal and external seals sandwiching a grease pocket, wherein the motor cap defines the end cap of the motor housing and provides a fluid outlet port that is in fluid communication with the fluid outlet path of the multi-lumen shaft, and the motor cap defines a part of the blood pump outlet path that is outside the internal and external seals and extends laterally outward from the motor cap.

40. The blood pump according to claim 31, further comprising an impeller shaft coupled to the impeller and extending distally from the bearing housing.

41. The blood pump according to claim 31, further comprising an impeller shaft attached to the impeller, the impeller shaft having at least one external surface division defining a portion of the outflow fluid path.

42. The blood pump according to claim 31, further comprising a bearing housing that holds a bearing surrounding one section of the impeller shaft, wherein the bearing has at least one radially extending conduit that defines at least one transverse fluid path in a state of fluid communication with a fluid inflow path provided at least in part by at least one inflow lumen of the multi-lumen shaft, and the bearing acts as a hydrostatic bearing.

43. The blood pump according to claim 42, further comprising proximal and distal bushings located on both sides of the bearing and spaced apart in the axial direction, wherein the proximal bushing is mounted on the impeller shaft, the torque cable, and the at least one support wire, and the distal bushing is mounted on the impeller shaft outside the bearing housing.

44. The blood pump according to claim 43, wherein the proximal and distal bushings are configured to define radially extending flanges and thrust washers having bearings between them.

45. The blood pump according to claim 31, further comprising an impeller shaft coupled to the impeller and the torque cable, wherein the impeller shaft defines a portion of the fluid outflow path that is in fluid communication with a transverse fluid path provided by bearings surrounding a portion of the impeller shaft.

46. The blood pump of claim 45, wherein a portion of the impeller shaft coupled to the impeller is surrounded by the bearing, and a biocompatible purge fluid from the at least one inlet lumen travels distally along a portion of the impeller shaft to the torque cable lumen, passing through holes in the bearing providing the transverse fluid path, and / or cooling and lubricating the torque cable.

47. The blood pump according to claim 46, wherein the bearing housing has an outer surface facing the impeller that defines the interface between the bearing and the impeller, and is configured such that a first amount of purge fluid exits the interface between the bearing and the impeller to the patient while maintaining sufficient fluid pressure to prevent blood from entering the bearing housing, while a larger amount of purge fluid exits the blood pump on an outflow path provided by the multi-lumen shaft.

48. The blood pump according to claim 31, configured to supply blood to the outlet cage at a rate of 2 to 7 liters, while continuously supplying a biocompatible fluid to at least one inlet lumen and to the outlet path.

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