Blood pump with encapsulated actuator

Abstract

This disclosure describes systems and methods for generating blood flow using a blood pump comprising a membrane and an encapsulated actuator. The pump may be implantable and may include: a stator assembly; an electromagnetic assembly supported by the stator assembly; a magnetic assembly; one or more springs attached to the stator and the magnetic assembly; and a packaging portion connecting the magnetic assembly to the stator assembly. The magnetic assembly may further be coupled to a membrane assembly comprising a flexible membrane. The electromagnetic assembly may be selectively activated to reciprocate the magnetic assembly, thereby reciprocating the membrane assembly and inducing undulations in the flexible membrane to pump blood from an inlet to an outlet of the pump. The encapsulation portion may prevent blood from interacting with an internal moving portion of the pump, thereby reducing the risk of hemolysis.

Description

[0001] CROSS REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 363,635 filed on April 26, 2022 and European Patent Application No. 22315090.5 filed on April 26, 2022, the entire contents of each of which are incorporated herein by reference. Technical Field

[0003] The present invention relates generally to blood pumps. For example, provided herein are systems and methods including an implantable heart pump with improved hydraulic performance that is designed to reduce hemolysis and platelet activation, such as by encapsulating an actuator assembly. Background Art

[0004] The human heart consists of four main chambers: two ventricles and two atria. Generally speaking, the right side of the heart receives oxygen-poor blood from the body into the right atrium and pumps it to the lungs via the right ventricle. The left side of the heart receives oxygen-rich blood from the lungs into the left atrium and pumps it to the aorta via the left ventricle for distribution throughout the body. Due to any of several diseases, including coronary artery disease, high blood pressure, valvular regurgitation and calcification, damage to the heart muscle caused by infarction or ischemia, myocarditis, congenital heart defects, abnormal heart rhythms, or various infectious diseases, the left ventricle may become less efficient and therefore unable to pump oxygenated blood throughout the body.

[0005] The American Heart Association estimates that approximately 6 million people in the United States suffer from some form of heart failure. Heart failure is generally classified into four different stages, the most severe of which is end-stage heart failure. Despite drug treatment, patients with end-stage heart failure may still experience heart failure symptoms at rest. Patients at this stage experience systolic heart failure, which is characterized by a reduced ejection fraction. In patients with systolic heart failure, the walls of the ventricles (which are usually thick in healthy patients) become thin and fragile. As a result, during heart contraction, a reduced volume of oxygenated blood is ejected into the blood circulation, which continues in a downward spiral until death. The one-year mortality rate for patients diagnosed with end-stage heart failure is approximately 50%.

[0006] For patients who have reached end-stage heart failure, treatment options are limited. In addition to continuing the medical therapy typically prescribed during early heart failure, treatment options are heart transplantation and implantation of mechanical assist devices. Although heart transplantation can significantly prolong a patient's life, only 3,000 to 3,500 transplants have been performed in the United States due to a lack of available donor organs. As a result, patients often wait on transplant waiting lists for months to years for a suitable donor heart. Currently, an alternative to heart transplantation is a circulatory assist device. Although the design of circulatory assist devices has improved in recent years, these implants typically only extend a patient's life by a few years at most and include several comorbidities.

[0007] One type of circulatory assist device that can be used for patients with end-stage heart failure is a left ventricular assist device (LVAD). An LVAD is a surgically implanted pump that draws oxygenated blood from the left ventricle and pumps it directly to the aorta, thereby unloading (reducing) the pumping work of the left ventricle. An LVAD is typically used as a "bridge therapy before transplantation," "bridge therapy before recovery," or "replacement therapy." When used as a bridge therapy before transplantation, an LVAD is used to extend the life of patients who are waiting for a heart transplant. In bridge therapy before recovery, the patient's natural heart recovers sufficient function during mechanical circulatory support, and the device can be removed or "retired" from the patient's body, with some remaining in place. When a patient is not suitable for a heart transplant, an LVAD can be used as a replacement therapy to extend life or improve the patient's quality of life, but this extension can only last for a few years.

[0008] In general, LVAD includes an inlet cannula, a pump and an outlet cannula, and is coupled to an external battery and a control unit. The inlet cannula is usually directly connected to the left ventricle (e.g., at the apex) and delivers blood from the left ventricle to the pump. The outlet cannula is usually connected to the aorta distal to the aortic valve and delivers blood from the pump to the aorta. Typically, a hose-type structure (e.g., a Dacron artificial blood vessel) is used to extend the outlet cannula of the pump to reach an appropriate delivery position on the aorta. Early LVAD designs were reciprocating, but rotary and centrifugal pumps have been used recently.

[0009] Isaacson's U.S. Patent No. 4,277,706, entitled "Actuator for Heart Pump," describes an LVAD with a reciprocating pump. The pump described in the Isaacson patent includes: a housing having an inlet and an outlet; a chamber inside the pump connected to the inlet and the outlet; a flexible membrane extending across the chamber; a plate fixed to the membrane; and a ball screw configured to reciprocate to drive the plate and connect the membrane from one end of the chamber to the other end to simulate heart contraction and heart relaxation. The ball screw is actuated by a direct current motor. The Isaacson patent also describes a controller configured to manage the rotation of the ball screw to control starting, stopping, and reversing of direction to control the flow of blood into and out of the pump.

[0010] Previously known reciprocating pump LVADs have several disadvantages. These pumps are typically large, heavy, and may require removal of intrathoracic tissue for implantation. They also require a large amount of energy to discharge blood through the compression chamber. Moreover, the pump subjects the blood to significant pressure fluctuations as it passes through the pump and causes high shear forces and hemolysis risks (e.g., due to valve and / or flow configurations). These pressure fluctuations may be exaggerated at higher blood flow rates. In addition, depending on the geometry of the pump, areas with less or no flow may cause flow stagnation, which may lead to thrombosis and may cause fatal medical conditions (e.g., stroke). Moreover, blood flowing through such a device may be destroyed when it contacts the moving components. For example, shear-induced damage may contribute to hemolysis. Finally, many positive displacement pumps as described in the Isaacson patent cannot achieve pulsatility similar to that of a natural heart (e.g., about 60 to 100 times per minute) while maintaining a physiological pressure gradient.

[0011] LVADs utilizing rotational and centrifugal configurations are also known. For example, U.S. Pat. No. 3,608,088 to Reich, entitled "Implantable Blood Pump," describes a centrifugal pump for assisting a failing heart. The Reich patent describes a centrifugal pump having an inlet connected to a rigid cannula coupled to the left ventricular cavity and a Dacron graft extending from the pump diffuser to the aorta. The pump includes an impeller that rotates at high speed to accelerate the blood and simulates the pulsation of a natural heart by varying the rotational speed or introducing a fluid oscillator.

[0012] U.S. Patent No. 5,370,509 to Golding, entitled "Sealless Rotodynamic Pump with Fluid Bearing," describes an axial blood pump that can be used as a heart pump. One embodiment described relates to an axial flow blood pump having impeller blades aligned with the axes of a blood inlet and a blood outlet. U.S. Patent No. 5,588,812 to Taylor, entitled "Implantable Electrical Axial-Flow Blood Pump," describes an axial flow blood pump similar to the Golding patent. The pump described in the Taylor patent has a pump housing that defines a cylindrical blood conduit through which blood is pumped from the inlet to the outlet, and rotor blades that rotate along the axis of the pump to accelerate the flow of blood through the blood conduit.

[0013] Although improvements have been made to previously known LVAD devices, these pump designs are not without problems. Like reciprocating pumps, rotary and centrifugal pumps are typically bulky and difficult to implant. Although a rotary pump is mechanically different from a positive displacement pump, it also exhibits undesirable characteristics. Like a positive displacement pump, a rotary pump applies significant shear forces to the blood, thereby creating a risk of hemolysis and platelet activation. The very nature of a disk or blade rotating about an axis results in regions of high and low speeds as well as vibration and heating. The areas near the leading and trailing edges of the blades and the gap between the blade tip and the housing experience the highest shear forces. Additionally, stagnation or low flow rates near the axis of rotation can lead to thrombosis.

[0014] Although centrifugal pumps are capable of producing pulsating flow by varying the rotational speed of the associated disks or blades, this only exacerbates the problems caused by the steep radial velocity profile and high shear forces. In common practice, the output (measured as flow rate at a given head) of currently available rotary pumps is controlled by varying the rotational speed of the pump. Taking into account the mass of the rotating components, the angular velocity of the rotating components, and the resulting inertia, the change in rotational speed may not be instantaneous but instead may be gradual. Therefore, although a centrifugal pump can mimic pulsating flow with speed changes, the resulting pulse may produce physiological pressure changes.

[0015] Furthermore, rotary pumps often result in non-physiological pressure changes being applied to the blood. If the rotational speed of the pump is varied to simulate pulsatile flow or to increase flow rate, the rotary pump is less likely to operate at its optimal operating point, thereby reducing efficiency and increasing energy losses and heat generation.

[0016] LVADs can also be configured to increase blood flow to match the patient's needs. Numerous publications and patents describe methods for adjusting LVAD pump flow to match the flow required by the patient. For example, U.S. Patent No. 7,520,850 to Brockway, entitled "Feedback control and ventricular assist devices," describes a system and method for controlling a ventricular assist device using pressure feedback. The system described in the Brockway patent attempts to maintain constant filling of the ventricles by measuring ventricular pressure and / or ventricular volume. Although such systems can achieve flow rates of up to 8 or 9 liters per minute, these flow rates are typically outside the effective operating range of current rotary pumps, which are typically tuned to operate in the range of 4 to 6 liters per minute. Therefore, increasing the flow rate in a rotary pump to match patient demand results in non-optimal pump performance.

[0017] Pumps other than rotary and positive displacement types for discharging fluids are known in the art. For example, U.S. Pat. Nos. 6,361,284 and 6,659,740 to Drevet, entitled "Vibrating Membrane Fluid Circulator," describe pumps in which a deformable membrane vibrates to propel fluid through a pump housing. In these patents, vibratory motion applied to the deformable membrane results in wave-like undulations in the membrane that propel fluid along a channel. Different flow rates can be achieved by controlling the excitation applied to the membrane.

[0018] U.S. Patent No. 7,323,961 to Drevet, entitled "Electromagnetic Machine with a Deformable Membrane," describes a device in which a membrane is coupled along an outer edge in a tensioned state to an electromagnetic device arranged to rotate about the membrane. As the electromagnetic device rotates, the outer edge of the membrane deflects slightly in a direction perpendicular to the plane of the membrane. These deflections cause wave-like fluctuations in the membrane that can be used to move a fluid in contact with the membrane.

[0019] U.S. Patent No. 9,080,564 to Drevet, entitled "Diaphragm Circulator," describes a tensioned deformable membrane in which fluctuations are generated by electromagnetically moving a magnetized ring attached to the outer edge of the deformable membrane over a coil. Axial displacement of the magnetized ring causes fluctuations of the membrane. As in the '961 patent, the membrane fluctuations can be controlled by manipulating the magnetic attraction. U.S. Patent No. 8,714,944 to Drevet, entitled "Diaphragm pump with a Crinkle Diaphragm of Improved Efficiency," and U.S. Patent No. 8,834,136 to Drevet, entitled "Crinkle Diaphragm Pump," teach similar types of vibrating membrane pumps.

[0020] None of the aforementioned patents to Delevingne describe a vibrating membrane pump suitable for use in a biological environment or capable of pumping blood for extended periods of time with a reduced risk of flow stagnation leading to thrombosis.

[0021] U.S. Patent Publications Nos. 2017 / 0290966 and 2017 / 0290967 to Botterbusch (each of which is incorporated herein by reference in its entirety) describe an implantable cardiovascular blood pump having a flexible membrane coupled to an electromagnetic actuator assembly that propagates wave-like undulations along the flexible membrane to propel blood through the pump while avoiding thrombosis, hemolysis, and / or platelet activation. The Botterbusch pump generates hydraulic power—flow and pressure—by transferring the linear motion of the electromagnetic actuator to a flexible membrane that deforms through interaction with the blood, thereby transferring energy to the blood. The flexible membrane is oriented at a 90° angle to the motion of the linear actuator so that the outer edge of the membrane is the first element to engage the blood. As a result, there is a risk of energy loss at the inlet of the membrane, which affects the hydraulic power generation of the pump.

[0022] There is a need for an energy-efficient implantable pump that is lightweight, small in size, and has a fast start and stop response and that can operate efficiently over a wide range of flow rates with improved hydraulic performance and minimal blood disruption. Summary of the invention

[0023] Provided herein are systems and methods for providing a blood pump for circulatory assistance. The pump system herein may be implanted in a patient or used in vitro. The pump system may be used for circulatory assistance, and may be, for example, atrial, ventricular, and / or vascular. The pump system may be an implantable pump system. The pump system may have a wave membrane capable of producing a wide range of physiological flow rates while applying low shear forces to the blood, thereby reducing hemolysis and platelet activation relative to previously known systems. The pump system may include a stator assembly, an electromagnetic assembly, a magnetic assembly, and a membrane assembly, as well as one or more encapsulator portions to encapsulate the electromagnetic assembly and prevent the moving components of the pump from damaging the blood. The pump system herein may also minimize areas within the pump that may be prone to thrombosis.

[0024] According to one aspect of the present invention, a blood pump may include: a housing having an inlet and an outlet and designed to be implanted at a patient's heart; a membrane disposed within the housing; an actuator disposed within the housing, the actuator being designed to reciprocate the membrane to pump blood; and a packaging assembly designed to encapsulate the actuator so that blood does not contact the actuator, the packaging assembly being disposed within the housing to define a flow channel between the housing and the packaging assembly. During operation, blood may enter the inlet, flow between the housing and the packaging assembly in the flow channel, and may be pushed across the membrane to the outlet to pump the blood. The pump may further include a magnetic assembly designed to move relative to the actuator assembly. The magnetic assembly is annular and disposed around the actuator. The blood pump may further include at least one spring coupled to the magnetic assembly and the actuator. The packaging assembly may include the magnetic assembly, and the packaging assembly also encapsulates at least one spring. The packaging assembly isolates the actuator from the blood path, which can reduce exposure of the blood to higher shear conditions in the actuator. The flow channel can be configured to minimize damage to von Willebrand factor multimers in the blood. The flow channel can be sized and configured to promote blood flow toward the outlet and prevent blood flow toward the inlet and / or configured to reduce recirculation of the blood. The flow channel can be sized and configured to reduce the risk of shear conditions of the blood in the flow channel.

[0025] According to another aspect of the present invention, a blood pump may include: a housing having an inlet and an outlet and designed to be implanted at a heart; an actuator disposed within the housing, the actuator including an electromagnetic assembly designed to generate a magnetic field; an upper stator coupled to a first side of the actuator; a lower stator coupled to a second side of the actuator; a magnetic assembly including at least one magnet, the magnetic assembly designed to reciprocate in response to the magnetic field; a first packaging portion coupled to the upper stator and the magnetic assembly; a second packaging portion coupled to the lower stator and the magnetic assembly; and a flexible membrane coupled to the magnetic assembly and configured to reciprocate in response to the magnetic assembly. The first packaging portion, the magnetic assembly, and the second packaging portion may encapsulate the actuator so that during operation, blood enters the inlet, flows between an inner wall of the housing and the first packaging portion, between the magnetic assembly and the second packaging portion, and is propelled across the flexible membrane to the outlet.

[0026] According to another aspect of the present invention, a blood pump may include: a housing having an inlet and an outlet, the outlet being designed to be in fluid communication with a patient's left ventricle; an actuator assembly including a stator assembly and an electromagnetic assembly designed to generate a magnetic field; the actuator assembly is disposed within the housing; a magnetic assembly designed to reciprocate in response to the magnetic field; and a packaging assembly coupled to the magnetic assembly and the stator assembly, the packaging assembly encapsulating the actuator; and a flexible membrane coupled to the magnetic assembly and designed to reciprocate in response to the magnetic assembly. During operation, blood may enter the inlet, flow between the inner wall of the housing and the magnetic assembly, between the stator assembly and the packaging assembly, and may be propelled across the flexible membrane to the outlet.

[0027] According to another aspect of the present invention, a method of pumping blood using a blood pump is provided. The method of pumping blood may include: providing a blood pump designed to be positioned at a ventricle of a patient; sending an electrical signal to an actuator to excite an electromagnetic assembly to generate a magnetic field. The blood pump may include: a housing having an inlet and an outlet, the outlet being designed to be in fluid communication with the ventricle of the patient; an actuator including a stator assembly and an electromagnetic assembly designed to generate a magnetic field, the actuator assembly being disposed within the housing; a magnetic assembly configured to reciprocate in response to the magnetic field; a packaging assembly coupled to the magnetic assembly and the stator assembly, the packaging assembly being designed to encapsulate the actuator; and a flexible membrane coupled to the magnetic assembly and configured to reciprocate in response to the magnetic assembly. The magnetic field may reciprocate the flexible membrane, thereby propagating waves along the flexible membrane, thereby moving blood from the inlet, between the inner wall of the housing and the magnetic assembly, between the stator assembly and the packaging assembly, across the flexible member and out of the outlet. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 An exemplary embodiment of a pump system of the present invention including a blood pump, a controller, a battery, a programmer, and a mobile device according to some aspects of the present invention is depicted.

[0029] Figure 2 yes Figure 1 Perspective view of a blood pump.

[0030] Figure 3A and 3B 1 and 2 are perspective and schematic diagrams, respectively, of electronic components of an exemplary embodiment of a controller of the present invention.

[0031] Figure 4 is a plan view of an external battery used in the pump system of the present invention.

[0032] Figure 5A and 5B 1 and 2 are respectively a perspective view and a schematic diagram of electronic components of an exemplary embodiment of a programmer of the present invention.

[0033] Figure 6 is a perspective view of a pump assembly of the present invention.

[0034] Figure 7 is a perspective cross-sectional view of a blood pump of the present invention.

[0035] Figure 8 is an exploded view of the blood pump of the present invention.

[0036] Fig. 9 is a perspective cross-sectional view of a pump assembly of the present invention.

[0037] Fig.10 is a perspective cross-sectional view of a membrane assembly of the present invention.

[0038] Fig.11 is a perspective cross-sectional view of a moving component of a pump assembly according to a first embodiment of the present invention.

[0039] Fig.12 is a cross-sectional view of a blood pump according to the present invention.

[0040] Fig.13 is a cross-sectional view of the lower portion of a blood pump depicting the flow channel and membrane assembly in a rest position.

[0041] Fig.14 is a cross-sectional view of the lower portion of a blood pump depicting the flow channel and membrane assembly as the membrane oscillates.

[0042] Fig.15A is used for Figure 1 0026] Cross-sectional view of an alternative exemplary embodiment of a blood pump of the present invention having improved hydraulic performance in a pump system of FIG. Fig. 15B yes Fig.15A Perspective view of a blood pump.

[0043] Fig.16A illustrates blood flow across a planar annular membrane support, while Fig. 16B Blood flow using a pump assembly having a skirt according to one aspect of the present invention is described. Fig. 16C A blood pump having an integrated portion incorporating a magnetic assembly within a housing is described, the magnetic assembly featuring a linear bearing element and a magnet, and Fig.16D A blood pump having an integrated portion incorporating a magnetic assembly and featuring a mechanical spring is described.

[0044] Fig.17 is a cross-sectional view of a blood pump with an encapsulated actuator assembly.

[0045] Fig.18 is an exploded view of a blood pump with an encapsulated actuator assembly.

[0046] Fig.19 is an exploded view of the moving magnet assembly.

[0047] Fig. 20A and 20B is a perspective view of a membrane assembly and an actuator assembly. Fig. 20C is a cross-sectional view of a portion of an actuator assembly and a membrane assembly.

[0048] Figures 21A to 21C is a cross-sectional view showing the movement of the membrane assembly.

[0049] Fig.22Ais a cross-sectional view of a blood pump including a packaged actuator assembly. Fig. 22B is a top perspective view of a blood pump including a packaged actuator assembly showing surfaces that come into contact with blood.

[0050] Fig.23 is an exploded view of a membrane assembly containing several sensor targets.

[0051] Fig.24 is a cross-sectional view of a blood pump with an encapsulated actuator assembly illustrating the main chamber of the present invention.

[0052] Fig.25 is a perspective view of an actuator assembly including grooves in the outer surface to prevent eddy currents from circulating in the stator.

[0053] Fig.26A is a cross-sectional view of the inlet block. Fig.26B is a top view of the inlet containing three flow channels.

[0054] Fig.27A is a cross-sectional view of a blood pump with a spring on the outside of the actuator assembly. Fig.27B is a cross-sectional view of a blood pump having a bearing on the outside of the actuator assembly.

[0055] Fig.28 is a cross-sectional view of a blood pump having a packaged actuator assembly with a bellows.

[0056] Fig.29A is a cross-sectional view of a blood pump having a flexure spring assembly. Fig.29B is a perspective view of a flexure spring assembly. DETAILED DESCRIPTION

[0057] The blood pump system of the present invention is particularly well suited for use as an implantable left ventricular assist device (LVAD) and includes an oscillating membrane pump suitable for long-term implantation in patients with end-stage heart failure. A blood pump system constructed according to the principles of the present invention includes a blood pump and an external battery, a controller, and a programmer. The blood pump system of the present invention may be implantable and / or may be a heart pump (e.g., an LVAD). The blood pump includes a housing having an inlet and an outlet, a flexible membrane, and an encapsulated actuator assembly. When configured as an LVAD, the housing includes an inlet cannula inserted into the patient's left ventricle near the apex of the heart and an outlet cannula surgically placed in fluid communication with the patient's aorta. By activating the actuator assembly within the blood pump, the membrane oscillates, thereby causing blood to be drawn into the pump through the inlet cannula and discharged into the aorta through the outlet cannula. The flow rate and pulsatility can be manipulated by changing one or more of the frequency, amplitude, and duty cycle of the actuator assembly.

[0058] To improve hydraulic performance, the blood pump may include a membrane assembly including a membrane and a skirt disposed within a housing to direct blood flow from the inlet toward the outlet of the pump. The skirt may be positioned within the housing so that blood flows across opposite sides of the skirt and toward the undulating membrane after activation of the pump. To enhance protection of blood flowing through the blood pump, the actuator assembly may be packaged using a packaging assembly so that a blood flow channel between an inlet cannula and an outlet cannula of the blood pump is defined by the packaging assembly of the blood pump and the inner surface of the housing.

[0059] Reference now Figure 1 , describing a pump system 10 constructed according to the principles of the present invention. The blood pump system 10 includes a pump 20, a controller 30, a battery 40, a programmer 50, and a software module optionally programmed to run on a mobile device 60. The pump 20 is configured to be implanted in the chest of a patient such that an inlet cannula 21 is coupled to the left ventricle LV of the heart H. The outlet cannula 22 of the pump 20 is configured to be coupled to the aorta A. The inlet cannula 21 is preferably coupled to the apex of the left ventricle LV, while the outlet cannula 22 is coupled to the aorta A near the ascending aorta, above the level of the cardiac arteries. The pump 20 may be affixed to the chest of the patient using ring suturing or other conventional techniques. The outlet cannula 22 (which may include a Dacron vascular graft or other synthetic material) is coupled to an outlet 23 of the implantable pump 20.

[0060] Now also refer to Figure 2 In a preferred embodiment, the pump 20 is composed of an upper housing portion 24 and a lower housing portion 25, the upper housing portion being joined to the lower housing portion along an interface 26, such as by threads or welding, to form a fluid-tight pump housing 27 that may have a cylindrical shape. The upper housing portion 24 includes an inlet cannula 21 and an electrical conduit 28 for receiving electrical wires from the controller 30 and the battery 40. The lower housing portion 25 includes an outlet 23 coupled to the outlet cannula 22, such as Figure 1 The pump housing 27 is made of a biocompatible material (eg, stainless steel or titanium) and is sized for implantation within the chest cavity of a patient.

[0061] Refer to Figure 1In one embodiment, the controller 30 and battery 40 are external to the body and are sized to be placed on a belt or garment worn by the patient. Both the controller 30 and the battery 40 are electrically coupled to the pump 20, for example, via a cable 29 extending through a percutaneous opening in the patient's skin and into an electrical conduit 28 of the pump housing 27. Illustratively, the battery 40 is electrically coupled to the controller 30 via a cable 41 integrated into the belt 42. In an alternative embodiment, the controller 30 may be enclosed within a biocompatible housing and sized to be implanted subcutaneously in the patient's abdominal cavity. In this alternative embodiment, the controller 30 may include a wireless transceiver for bidirectional communication with an external programming device and also include a battery that is continuously and inductively charged via the external battery 40 and an external charging circuit. As should be understood, the aforementioned alternative embodiment avoids the use of a percutaneous cable 29 and thus eliminates a frequent source of infection for conventional LVAD devices.

[0062] The battery 40 preferably comprises a rechargeable battery capable of charging the pump 20 and controller 30 for several hours (e.g., 4 to 12 hours) before requiring recharging. The battery 40 may include a separate charging circuit (not shown) as is common with rechargeable batteries. The battery 40 is preferably disposed within a housing suitable for carrying on a belt or holster so as not to interfere with the patient's daily activities.

[0063] The programmer 50 may be comprised of a conventional laptop computer that is programmed to execute programming software routines for use by a clinician or medical professional to configure operating parameters and to provide the operating parameters to the controller 30. The configuration and operating parameter data is stored in a memory associated with the controller 30 and is used by the controller to control the operation of the pump 20. As described in further detail below, the controller 30 directs the pump 20 to operate at specific parameters determined by the programmer 50. The programmer 50 is preferably coupled to the controller 30 via the cable 51 only when initially setting or periodically adjusting the operating parameters of the pump (e.g., when the patient sees the clinician).

[0064] According to another aspect of the present invention, the mobile device 60, which may be a conventional smart phone, may include an application for two-way and wireless communication with the controller 30, such as via WiFi or Bluetooth communications. The application on the mobile device 60 may be programmed to allow the patient to send instructions to the controller to modify or adjust a limited number of operating parameters of the pump 20 stored in the controller 30. Alternatively or in addition, the mobile device 60 may be programmed to receive from the controller 30 and display on a screen 61 of the mobile device 60 data regarding the operation of the pump 20 or alarms or status messages generated by the controller 30.

[0065] about Figure 3A and 3B , the controller 30 is described in more detail. Figure 1, the controller 30 may be sized and configured to be worn on the outside of the patient's body and may be incorporated into clothing (e.g., a belt or vest). The controller 30 includes an input port 31, a battery port 32, an output port 33, an indicator light 34, a display 35, a status light 36, and a button 37.

[0066] Input port 31 is configured to periodically and removably accept cable 51 to establish an electrical connection between programmer 50 and controller 30 via, for example, a USB connection. In this way, a clinician can couple to controller 30 to set or adjust operating parameters stored in controller 30 for controlling the operation of the pump. Additionally, when programmer 50 is coupled to controller 30, the clinician can also download data about the operation of the pump (e.g., actuation statistics) from controller 30 for processing and presentation on a computer. Figure 5A 5. Alternatively or in addition, controller 30 may include a wireless transceiver for wirelessly communicating with programmer 50 regarding this information. In this alternative embodiment, the wireless communication between controller 30 and programmer 50 may be encrypted using an encryption key associated with the controller's unique identification number (e.g., serial number).

[0067] The battery port 32 is configured to removably receive a cable 41 ( Figure 1 The battery port 32 may be configured to receive a cable 41 that is coupled to the patient's back (illustratively shown in FIG. 4 as being integrated with the belt 42) such that the cable 41 is routed through the belt and extends around the patient's back until it is coupled to the controller 30. In this manner, the battery 40 may be removed from the belt 42 and disconnected from the controller 30 to enable the patient to periodically replace the battery with a fully charged battery. It is contemplated that the patient will have at least two batteries available to him or her so that while one battery is coupled to the controller 30 to power the controller and pump, the other battery may be connected to a recharging station. Alternatively or in addition, the battery port 32 may be configured to accept a cable that is coupled directly to a power source, this substantially larger battery / charger combination allowing the patient to remove the battery 40 while lying supine in bed (e.g., sleeping).

[0068] The output port 33 is electrically coupled to the cable 29, which in turn is coupled to the pump 20 through the electrical conduit 28 of the pump housing 27. The cable 29 provides both energy to power the pump 20 according to the configuration settings and operating parameters stored in the controller 30 and to receive data from sensors disposed in the pump 20. In one embodiment, the cable 29 may include a cable with a biocompatible coating and be designed to extend percutaneously. The cable 29 may be impregnated with drugs to reduce the risk of infection, the transmission of potentially hazardous substances, or to promote healing where it extends through the patient's skin and tissue.

[0069] As mentioned above, the controller 30 may include an indicator light 34, a display 35, a status light 36, and a button 37. The indicator light 34 may visually display information related to the operation of the system, such as the remaining life of the battery 40. The display 35 may be a digital LCD display that displays real-time pump performance data, physiological data of the patient (e.g., heart rate), or operating parameters of the pump (e.g., target pump pressure or flow rate), etc. When certain parameter conditions are determined to exceed preprogrammed thresholds, an alarm may be sounded, an alarm may be displayed on the display 35, and / or an internal vibration element may vibrate the controller 30 to provide tactile stimulation. The status light 36 may include a light emitting diode (LED) that turns on or off to indicate whether a certain functionality of the controller or pump is functioning. The button 37 may be used to wake up the display 35 to set or calm an alarm, etc.

[0070] about Figure 3B ,describe Figure 3A The components of the illustrative embodiment of the controller 30. Figure 3A In addition to the components of the controller 30 described above, the controller 30 further includes a microprocessor 38, a memory 39, a battery 43, an optional transceiver 44, and an amplifier circuit 45. The microprocessor may be a general purpose microprocessor in which programming for controlling the operation of the pump 20 is stored in the memory 39. The memory 39 may also store configuration settings and operating parameters of the pump 20. The battery 43 supplies power to the controller 30 to provide operational continuity when the battery 40 is periodically swapped out. The optional transceiver 44 (e.g., a communication unit) facilitates communication via any of several well-known communication standards, including BLUETOOTH. TM , ZigBee and / or any IEEE 802.11 wireless standard (e.g., Wi-Fi or Wi-Fi Direct)) to wirelessly communicate with the programmer 50 and / or the mobile device 60. The controller 30 may further include an amplifier circuit 49 for amplifying the electrical signals transmitted between the controller 30 and the pump 20.

[0071] Reference now Figure 4, depicting a battery 40. The battery 40 provides power to the pump 20 and may also provide power to the controller 30. The battery 40 may be comprised of a single battery or a plurality of batteries disposed within a housing, and is preferably sized and configured to be worn externally on the patient's body (e.g., on a belt 42). A battery life indicator 46 may be provided on the exterior of the battery 40 to indicate the remaining charge of the battery. A cable 41 may have one end removably coupled to the battery 40 and the other end removably coupled to the battery port 32 of the controller 30 to supply power to power the pump 20. In one embodiment, the battery 40 may be recharged using a separate charging station, as is known in the art of rechargeable batteries. Alternatively or in addition, the battery 40 may include a port 47 that is removably coupled to a transformer and cable to enable the battery to be recharged using a conventional household electrical outlet (e.g., 120V, 60Hz AC power).

[0072] Reference now Figures 5A to 5B , describing the programmer 50. The programmer 50 may be a conventional laptop or tablet computer loaded with a programming software routine that is used to configure the controller 30 and set the operating parameters used by the controller 30 to control the operation of the pump 20. As discussed above, the programmer 50 is typically located in a clinician's office or hospital and is coupled to the controller 30 via a cable 51 or wirelessly to first set up the controller 30, and then thereafter periodically adjust the operating parameters that may be required as needed. The operating parameters of the controller 30 set using the programming routine of the programmer 50 may include, but are not limited to, pump operating mode, applied voltage, pump frequency, pump amplitude, target flow rate, pulsatility, and the like. When initially implanted, the surgeon or clinician may use the programmer 50 to transfer the initial operating parameters to the controller 30. After implantation, the patient may return to the clinician's office periodically to adjust the operating parameters, which may again be done using the programmer 50.

[0073] Programmer 50 may be any type of conventional personal computer device, such as a laptop computer or a tablet computer with touch screen capability. Figure 5B As shown in FIG. 1 , the programmer 50 preferably includes a processor 52, a memory 53, an input / output device 54, a display 55, a battery 56, and a communication unit 57. The memory 53 may include an operating system for the programmer and programming routines required to communicate with the controller 30. The communication unit 57 may include any of several well-known communication protocols, such as BLUETOOTH. TM , ZigBee and / or any IEEE 802.11 wireless standard (e.g., Wi-Fi or Wi-Fi Direct). Figure 5A, the programming routine used to program and communicate with controller 30 may also provide data identifying the operating parameters used by controller 30 to control pump 20 for display on the screen of programmer 50. The programming routine may also enable programmer 50 to download operational data or physiological data transmitted by the pump from controller 30 and display the information in real time when the programmer is coupled to the controller via a wired or wireless connection. The transmitted data may then be processed and displayed on the screen of programmer 50.

[0074] Reference now Figure 6 and 7 , illustrating a preferred embodiment of the pump assembly 70 and the pump 20. However, it should be understood that the pump assembly and the pump and the components contained therein may have different configurations without departing from the invention described herein. Figure 6 and 7 The shape and size described in the Figure 7 , the pump assembly 70 is configured to fit within the pump housing 27. To secure the pump assembly 70 within the pump housing 27, the pump assembly 70 may include a retaining ring 71 that may extend from and around the stator assembly 72 and may be captured between the upper housing portion 24 and the lower housing portion 25 when the housing portions are assembled, such as Figure 7 . In this way, the stator assembly 72 can be suspended within the pump housing to be in a close fitting relationship with the inner wall of the pump housing. The fixing ring 71 is preferably a rigid annular structure disposed concentrically around the stator assembly 72 and having a diameter greater than the stator assembly 72. The fixing ring 71 can be rigidly coupled to the stator assembly 72 via the support 73. The support 73 can create a gap 74 between the fixing ring 71 and the stator assembly 72, which is preferably about 0.05 mm at its most restricted point.

[0075] like Figure 7 , the pump assembly 70 can be disposed in the pump housing 27 such that the retaining ring 71 is captured on a step 75 formed between the upper housing portion 24 and the lower housing portion 25. In this way, the stator assembly 72 can be suspended within the pump housing 27 and prevented from moving within the pump housing. The pump housing 27 is preferably sized and configured to conform to the pump assembly 70 so that the stator assembly 72 does not contact the interior of the pump housing at any location other than at the retaining ring 71.

[0076] Figure 82 is an exploded view of the pump 20, which depicts the arrangement of the internal components of the pump assembly 70 arranged between the upper housing portion 24 and the lower housing portion 25. In particular, the pump assembly 70 may include a stator assembly 72, a magnetic ring assembly 76, a first electromagnetic coil 77, a second electromagnetic coil 78, a fixed ring 71, a first suspension ring 79, a second suspension ring 80, a post 81, and a membrane assembly 82. The stator assembly 72 may include a tapered section 83, electromagnetic coil holder portions 84, 85, and 86, and a flange portion 87. The magnetic ring assembly 76 may include a magnetic ring 88 and magnetic ring holder portions 89 and 90. The first electromagnetic coil 77 and the second electromagnetic coil 78 together with the electromagnetic coil holder portions 84, 85, and 86 may form an electromagnetic assembly 91. The electromagnetic assembly 91 together with the stator assembly 72 forms an actuator assembly. The actuator assembly together with the magnetic ring assembly 76 in turn forms an actuator system of the pump 20.

[0077] The first electromagnetic coil 77 and the second electromagnetic coil 78 can be concentrically sandwiched between the electromagnetic coil holder portions 84, 85 and 86 to form the electromagnetic assembly 91. The tapered section 83 (which can be coupled to the fixed ring 71 and the first suspension spring 79) can be concentrically positioned atop the electromagnetic assembly 91. The magnetic ring 88 can be disposed together with the magnetic ring holder portions 89 and 90 to form the magnetic ring assembly 76, which can be concentrically disposed to reciprocate above the electromagnetic assembly 91. The second suspension ring 80 can be concentrically disposed below the electromagnetic assembly 91. The flange portion 87 can be concentrically disposed below the second suspension ring 80. The post 81 can engage the first suspension ring 79, the magnetic ring assembly 76 and the second suspension ring 80 at equally spaced locations around the actuator assembly. The membrane assembly 82 can be concentrically positioned below the flange portion 87 and engaged with the post 81.

[0078] about Fig. 9 Further details of the pump assembly 70 are provided. Specifically, the actuator assembly 95 includes the stator assembly 72 and the electromagnetic assembly 91 (including the first electromagnetic coil 77 and the second electromagnetic coil 78). During use of the pump 20, the actuator assembly 95 remains fixed relative to the pump housing 27. The first electromagnetic coil 77 and the second electromagnetic coil 78 can be separated by the electromagnetic retainer portion 85. The controller 30 and the battery 40 are electrically coupled to the electromagnetic coils 77 and 78 via the cable 29 extending through the electrical conduit 28 of the pump housing 27 to supply current to the electromagnetic coils 77 and 78. The first electromagnetic coil 77 and the second electromagnetic coil 78 can be electrically connected to each other or can be configured to operate separately and have separate wired connections with the controller 30 and the battery 40 via the cable 29.

[0079] The electromagnetic coils 77 and 78 may be made of any conductive metal material (e.g., copper) and may further include one or more smaller metal wires wound into a coil. The wires of the electromagnetic coils are insulated to prevent shorting to adjacent conductive materials. Other components of the pump assembly 70 (e.g., the stator assembly 72) are also preferably insulated and / or made of non-conductive materials to reduce undesired transmission of electrical signals.

[0080] The actuator assembly 95 may be surrounded by a first suspension ring 79 and a second suspension ring 80. The suspension rings 79 and 80 may have an annular shape and fit concentrically around the actuator assembly 95. The first suspension ring 79 is preferably rigidly attached to a tapered section 83 near the top of the stator assembly 72 via a post 73 extending from the suspension ring to the stator assembly. As discussed above, the post 73 may also attach the fixed ring 71 to the stator assembly 72. The fixed ring 71 and the first suspension spring 79 may be sized and positioned so that there is a gap of no less than 0.5 mm between the first suspension ring 79 and the fixed ring 71. The second suspension ring 80 may similarly be attached to the bottom of the stator assembly 72 below the electromagnetic assembly 91 via a post. The suspension rings 79 and 80 are preferably sized and shaped so that when the suspension rings 79 and 80 are positioned around the actuator assembly 95, there is a gap of no less than 0.5 mm between the actuator assembly 95 and the suspension rings 79 and 80.

[0081] The first suspension ring 79 and the second suspension ring 80 may include stainless steel, titanium, or cobalt-chromium alloys that have elastic properties and exhibit spring force when deflected in a direction perpendicular to the plane of the spring. The first suspension ring 79 and the second suspension ring 80 may be substantially rigid relative to tangential forces applied to the suspension rings. In this way, the first suspension ring 79 and the second suspension ring 80 may exhibit spring tension when deformed upward and downward relative to the vertical axis of the actuator assembly but may be rigid against movement along any other axis (e.g., tilting or twisting movement).

[0082] The magnetic ring assembly 76 may have an annular shape and concentrically surround the actuator assembly 95. The magnetic ring 88 may include one or more materials that exhibit magnetic properties, such as iron, nickel, cobalt, or various alloys. The magnetic ring 88 may be made of a single unitary component or include several magnetic components coupled together. The magnetic ring assembly 76 may be sized and shaped so that when it is concentrically positioned above the actuator assembly 95, there is a gap of no less than 0.5 mm between the outer lateral surface of the actuator assembly 95 and the inner surface of the magnetic ring assembly 76.

[0083] The magnetic ring assembly 76 may be positioned concentrically around the actuator assembly 95 between the first suspension ring 79 and the second suspension ring 80 and may be rigidly coupled to the first suspension ring 79 and the second suspension ring 80. The magnetic ring assembly 76 may be rigidly coupled to the suspension ring by one or more posts 81 evenly spaced around the actuator assembly 95 and configured to extend parallel to the central axis of the pump assembly 70. The suspension rings 79 and 80 and the magnetic ring assembly 76 may be engaged so that the magnetic ring assembly 76 is equally suspended between the first electromagnetic coil 77 and the second electromagnetic coil 78 when the suspension ring has a non-deflected shape. Each of the suspension rings 79 and 80 and the magnetic ring holder portions 89 and 90 may include a post receiving area for engaging with the posts 81 or may be attached to the posts 81 in any suitable manner that results in the suspension rings 79 and 80 and the magnetic ring assembly 76 being rigidly attached to the posts 81. Post 81 may extend beyond suspension rings 79 and 80 to engage other components, such as flange portion 87 and membrane assembly 82 .

[0084] The first electromagnetic coil 77 can be activated by applying an electrical signal from the battery 40 to the first electromagnetic coil 77 by a controller, thereby inducing a current in the electromagnetic coil and generating a magnetic field around the electromagnetic coil 77. The direction of the current in the electromagnetic coil 77 and the polarity of the magnetic ring assembly 76 closest to the electromagnetic coil 77 can be configured so that the first electromagnetic coil magnetically attracts or repels the magnetic ring assembly 76 as needed. Similarly, a magnetic field can be generated in the second electromagnetic coil 78 by introducing a current in the second electromagnetic coil. The direction of the current in the second electromagnetic coil 78 and the polarity of the magnetic ring assembly 76 closest to the second electromagnetic coil can also be similarly configured so that when the appropriate current is induced in the second electromagnetic coil 78, the first electromagnetic coil 77 magnetically attracts or repels the magnetic ring assembly 76.

[0085] Since the magnetic ring assembly 76 can be rigidly attached to the post 81, which in turn can be rigidly attached to the first suspension ring 79 and the second suspension ring 80, the elastic properties of the suspension rings allow the magnetic ring assembly 76 to move upward toward the first electromagnetic coil 77 or downward toward the second electromagnetic coil 78, depending on the polarity of the magnetic field generated by the electromagnetic rings. In this way, when the magnetic ring assembly 76 experiences an upward magnetic force, the magnetic ring assembly 76 deflects upward toward the first electromagnetic coil 77. As the post 81 moves upward with the magnetic ring assembly 76, the post 81 causes the suspension rings 79 and 80 to elastically deform, which generates a spring force opposite to the direction of movement. When the magnetic field generated by the first electromagnetic coil disappears, when the current stops, this downward spring force causes the magnetic ring assembly to return to its neutral position. Similarly, when the magnetic ring assembly 76 is magnetically attracted downward, the magnetic ring assembly 76 deflects downward toward the second electromagnetic coil 78. As the post 81 moves downward with the magnetic ring assembly 76, the post 81 applies elastic deformation of the first and second suspension rings, thereby generating spring forces in opposite directions. When the magnetic field generated by the second electromagnetic ring disappears, when the current stops, this upward spring force causes the magnetic ring assembly to return to its neutral position again.

[0086] The electromagnetic coils 77 and 78 may be energized individually, or alternatively, may be connected in series to cause the electromagnetic coils to be activated simultaneously. In this configuration, the first magnetic coil may be configured to experience a current direction opposite to that of the second electromagnetic coil. Thus, when current is induced to the first electromagnetic coil 77 to attract the magnetic ring assembly 76, the same current is applied to the second electromagnetic coil 78 to induce a current that causes the second electromagnetic coil 78 to repel the magnetic ring assembly 76. Similarly, when current is induced to the second electromagnetic coil 78 to attract the magnetic ring assembly 76, the current applied to the first electromagnetic coil 77 causes the first electromagnetic coil to repel the magnetic ring assembly 76. In this way, the electromagnetic coils 77 and 78 work together to cause deflection of the magnetic ring assembly 76.

[0087] By manipulating the timing and strength of the electrical signals applied to the electromagnetic coils, the frequency at which the magnetic ring assembly 76 deflects toward the first and second electromagnetic coils can be altered. For example, by alternating the current induced in the electromagnetic coils more frequently, the magnetic ring assembly can be caused to cycle up and down more times in a given period of time. By increasing the amount of current, the magnetic ring assembly can be deflected at a faster rate and can be caused to travel a longer distance.

[0088] Alternatively, the first electromagnetic coil 77 and the second electromagnetic coil 78 may be energized independently. For example, the first electromagnetic coil 77 and the second electromagnetic coil 78 may be energized at different strengths; one may be coordinated to decrease in strength as the other increases in strength. In this way, as the strength of the signal applied to the first electromagnetic coil 77 results in a decreasing upward magnetic attraction, the strength of the signal applied to the second electromagnetic coil 78 to cause downward magnetic attraction may simultaneously increase.

[0089] According to one aspect of the present invention, the movement of the magnetic ring assembly 76 can be transferred to a membrane assembly 82 which can be disposed concentrically below the stator assembly 72. The membrane assembly 82 is preferably rigidly attached to the magnetic ring assembly 76 by posts 81. Fig. 9 In the embodiment depicted in , the post 81 may extend beyond the second suspension ring 80 and be coupled to the membrane assembly 82 .

[0090] Reference now Fig.10 , an embodiment of the membrane assembly 82 is described in more detail. The membrane assembly 82 may include a rigid membrane ring 96 and a membrane 97. The rigid membrane ring 96 exhibits rigid properties under typical forces experienced during the entire operating range of the present invention. A post receiving position 98 may be formed into the rigid membrane ring 96 to engage the membrane assembly 82 and the post 81. Alternatively, the post 81 may be attached to the rigid membrane ring 96 in any other manner, which transfers the movement of the magnetic ring assembly 76 to the rigid membrane ring 96. The rigid membrane ring 96 may be attached to the membrane 97 and keep the membrane taut. The membrane 97 may be molded directly onto the rigid membrane ring 96 or may be attached to the rigid membrane ring 96 in any manner, which keeps the membrane 97 uniformly tensioned along its circumference. The membrane 97 may alternatively include a flexible folding structure, wherein it is attached to the rigid membrane ring 96 to increase the ability of the membrane to move, wherein the membrane is attached to the rigid membrane ring 96. The membrane 97 may further include a circular hole 99 disposed in the center of the membrane.

[0091] In a preferred embodiment, the membrane 97 has a thin, planar shape and is made of an elastomer having elastic properties and good durability. Alternatively, the membrane 97 may have a uniform thickness from the membrane ring to the circular hole. As a further alternative, the thickness of the membrane 97 may vary and exhibit a more complex geometry. For example, Fig.10 , the membrane 97 may have a decreasing thickness as the membrane extends from the rigid membrane ring 96 to the circular hole 99. Alternatively or in addition, the membrane 97 may incorporate a metal element (e.g., a coil spring) to enhance the spring force of the membrane in a direction perpendicular to the plane of the membrane, and this spring force may vary radially along the membrane. In yet another embodiment, the membrane 97 may be preformed with an undulating shape.

[0092] Fig.11 Depiction Figures 6 to 92 shows the moving portion of an embodiment of the pump assembly 70 as a non-ashing element. The non-moving portion of the pump assembly, including the actuator assembly 95 and the electromagnetic assembly 91 (partially shown), can be fixed to the pump housing 27 by the fixed ring 71. The moving portion of the pump assembly 70 can include a column 81, a first suspension spring 79, a magnetic ring assembly 76, a second suspension spring 80, and a membrane assembly 82. As the magnetic ring assembly 76 moves up and down, the movement is rigidly transferred to the membrane assembly 82 by the column 81. Taking into account the rigidity of the column, when the magnetic ring assembly 76 moves a certain distance up or down, the membrane assembly 82 can travel the same distance. For example, when the magnetic ring assembly 76 travels 2mm from a position near the electromagnetic coil 77 to a position near the second electromagnetic coil 78, the membrane assembly 82 can also travel 2mm in the same direction. Similarly, the frequency at which the magnetic ring assembly 76 traverses the space between the first and second electromagnetic coils can be the same as the frequency at which the membrane assembly 82 travels the same distance.

[0093] Reference now Fig.12 ,exist Figures 6 to 9 In the embodiment of the pump 20 described in , blood may enter the pump 20 from the left ventricle through the inlet cannula 21 and flow down the pump assembly 70 into the delivery channel 100, which is defined by the inner surface of the pump housing 27 and the exterior of the pump assembly 70. The delivery channel 100 begins at the top of the stator assembly 72 and extends between the tapered section 83 and the interior of the pump housing 27. As the blood moves downward to the tapered section 83, it is directed through the gap 74 and into the vertical portion of the delivery channel 100 in the area between the pump housing 27 and the actuator assembly 95, and is contained in the gap between the magnetic ring assembly 76 and the electromagnetic assembly 91. The delivery channel 100 extends downward to the flange portion 87 of the stator assembly 72, which routes the blood into the flow channel 101 within which the membrane assembly 82 is suspended. The delivery channel 100 delivers the blood to the membrane assembly 82 by directing the blood from the inlet cannula 21 through the delivery channel 100 to the flow channel 101. By actuating the electromagnetic coils 77 and 78, the membrane 97 can undulate within the flow channel 101 to cause wave formation in the membrane 97 moving from the edge of the membrane toward the circular hole 99. Thus, when blood is delivered from the delivery channel 100 to the membrane assembly 82, it can be radially propelled along both the top and bottom of the membrane 97 toward the circular hole 99 and exit the outlet 23 therefrom.

[0094] According to one aspect of the invention, the oscillating membrane pump described herein reduces thrombosis by placing moving parts directly within the main flow path, thereby reducing the risk of flow stagnation. Specifically, Fig.11The moving components depicted in the figure (including the magnetic ring assembly 76, the suspension rings 79 and 80, the column 81 and the membrane assembly 82) are all positioned within the delivery channel 100 and the flow channel 101. Flow stagnation can be further avoided by eliminating secondary flow paths that can experience significantly slower flow rates. The width of the fluid channel (i.e., the delivery channel 100 and the flow channel 101) can be optimized to minimize the exposure of blood to shear conditions. The flow channel can be sized and shaped to optimize hydraulic performance. In particular, the flow channel 101 can be sized and configured to promote blood flow toward the outlet and prevent blood from flowing toward the inlet. It should be understood that the size and shape of the flow channel can affect the blood flow through the pump, and the optimal size and shape can be selected to optimize hydraulic performance. For example, the size and shape of the flow channel can be optimized to prevent backflow and recirculation while allowing forward flow; therefore, backflow is prevented without blocking forward flow.

[0095] Now turn to Fig.13 and 14 , showing the lower portion of the pump 20 including the flange portion 87, the membrane assembly 82, and the lower housing portion 25. The delivery channel 100 can be in fluid communication with the membrane assembly 82 and the flow channel 101, the flow channel being defined by the bottom surface of the flange portion 87 and the inner surface of the lower housing portion 25. The flange portion 87 can include a feature 102 that extends downward as the flange portion 87 moves radially inward. The inner surface of the lower housing portion 25 can also be inclined upward as it extends radially inward. The combination of the upward inclination of the inner surface of the lower housing portion 25 and the downward movement of the bottom surface of the flange portion 87 narrows the flow channel 101 because the channel moves radially inward from the delivery channel 100 to the circular hole 99 of the membrane 97 disposed around the pump outlet 23.

[0096] As explained above, the membrane assembly 82 can be suspended by the posts 81 in the flow channel 101 below the bottom surface of the flange portion 87 and above the inner surface of the lower housing portion 25. The membrane assembly 82 can freely move up and down in the vertical direction in the flow channel 101, and this movement is only limited by the suspension rings 79 and 80. The membrane assembly 82 can be restricted by the rigid posts 81 and the suspension rings from twisting, tilting, or moving in any direction in the flow channel 101 (except for up and down movement).

[0097] Flow channel 101 is divided into an upper flow channel and a lower flow channel by membrane 97. The geometry of membrane 97 may be angled so that when membrane assembly 82 is at rest, the top surface of membrane 97 is parallel to the bottom surface of flange portion 87 and the bottom surface of membrane 97 is parallel to the opposing surface of lower housing portion 25. Alternatively, membrane 97 may be sized and shaped so that when membrane assembly 82 is at rest, the upper and lower flow channels narrow as they move radially inward from delivery channel 100 to circular hole 99 in membrane 97.

[0098] Now also refer to Fig.14 , when the rigid membrane ring 96 is caused to move up and down in the flow channel 101 by the post 81, the outermost portion of the membrane 97 closest to the rigid membrane ring 96 moves up and down with the rigid membrane ring 96. The membrane 97 (which is flexible and has elastic properties) causes the up and down movement of the portion of the membrane closest to the rigid membrane ring 96 to gradually transfer along the membrane 97 toward the circular hole 99. This movement across the flexible membrane 97 causes a wave-like deformation in the membrane, which can propagate inward from the rigid membrane ring 96 toward the hole 99.

[0099] The waves formed in the fluctuating membrane can be manipulated by changing the frequency at which the rigid membrane ring 96 moves up and down and the distance that the rigid membrane ring 96 moves up and down. As explained above, the amplitude and frequency of the up and down movement of the rigid membrane ring 96 are determined by the amplitude and frequency of the reciprocation of the magnetic ring assembly 76 above the electromagnetic assembly 91. Therefore, the waves formed in the fluctuating membrane can be adjusted by changing the frequency and amplitude of the reciprocation of the magnetic ring assembly 76.

[0100] When blood is introduced from delivery channel 100 into flow channel 101, undulations in membrane 97 cause the blood to be propelled toward circular aperture 99 and out of pump housing 27 via outlet 23. Energy transfer from the membrane to the blood is directed radially inward along the length of the membrane toward aperture 99 and along both sides of membrane 97 to propel the blood along the flow channel toward outlet 23.

[0101] For example, when the rigid membrane ring 96 moves downward with the magnetic ring assembly 76, the upper portion of the flow channel 101 near the delivery channel 100 expands, causing blood from the delivery channel 100 to fill the upper portion of the flow channel near the outer region of the membrane 97. As the rigid membrane ring 96 moves upward, the upper portion of the flow channel 101 begins to narrow near the rigid membrane ring 96, causing the wave-like deformation to transfer across the membrane. As the wave propagates across the membrane 97, the blood in the upper portion of the flow channel 101 is pushed toward the circular hole and eventually leaves the pump housing 27 through the outlet 23. At the same time, as the rigid membrane ring 96 moves upward, the lower portion of the flow channel 101 closest to the outside of the membrane 97 begins to expand, allowing blood to flow from the delivery channel 100 into this area. Subsequently, when the rigid membrane ring 96 pushes downward again, the lower region of the flow channel 101 closest to the outside of the membrane 97 begins to narrow, causing the wave-like deformation to transfer across the membrane, which pushes the blood toward the outlet 23.

[0102] By manipulating the waves formed in the undulating membrane by varying the frequency and amplitude of the up and down movement of the magnetic ring assembly 76, the pressure gradient within the flow channel 101 can be adjusted and ultimately the flow rate of blood moving through the flow channel 101 can be adjusted. Proper control of the movement of the magnetic ring assembly 76 allows oxygen-rich blood to be effectively and safely pumped from the left ventricle to the aorta and throughout the body as needed.

[0103] In addition to only pumping blood from the left ventricle to the aorta, the pump 20 of the present invention can be operated to accurately mimic physiological pulsatility without losing pump efficiency. In the embodiments described in detail above, pulsatility can be achieved almost instantly by changing the frequency and amplitude of the movement of the magnetic ring assembly 76 to produce a desired flow output or by stopping the movement of the magnetic ring assembly for a period of time to produce a period with low flow output or no flow output. Unlike a typical rotary pump that requires a certain period of time to reach a set number of rotations per minute to achieve the desired fluid displacement and pulsatility, the pump 20 can reach the desired flow output almost instantly due to the very low inertia generated by the small moving mass of the moving components of the pump assembly and similarly can stop output almost instantly. The ability to start and stop as needed allows rapid changes in pressure and flow. The duty cycle defined by the percentage of time of the membrane 97 excited in the set period can be adjusted together with the frequency and amplitude to achieve the desired flow output and pulsatility without losing pump efficiency. Even if the frequency and amplitude are kept constant, the flow rate can be changed by manipulating the duty cycle between 0 and 100%.

[0104] According to another aspect of the present invention, the controller 30 can be programmed by the programmer 50 to operate at a selected frequency, amplitude, and duty cycle to achieve a wide range of physiological flow rates and with physiological hemodynamics. For example, the programmer 50 can direct the controller 30 to operate the pump 20 at a given frequency, amplitude, and / or duty cycle during periods when the patient is typically asleep and can direct the controller 30 to operate the pump 20 at a different frequency, amplitude, and or duty cycle during periods when the patient is typically awake. The controller 30 or the pump may also include an accelerometer or position indicator to determine whether the patient is supine or ambulatory, the output of which can be used to move from one set of pump operating parameters to another set of pump operating parameters. When the patient experiences some discomfort or the physician determines that the parameters are not optimal, the physician can modify at least one or more of the frequency, amplitude, and duty cycle to achieve the desired functionality. Alternatively, the controller 30 or the mobile device 60 can be configured to modify one or more of the frequency, amplitude, and duty cycle to accommodate the patient's needs.

[0105] The pump 20 may further include one or more additional sensors for adjusting the flow output and pulsatility according to the patient's needs. The sensors may be incorporated into the pump 20 or alternatively or additionally may be implanted elsewhere in or on the patient. The sensors are preferably in electrical communication with the controller 30 and may monitor operating parameters that measure the performance of the pump 20 or physiological sensors that measure physiological parameters of the patient (e.g., heart rate or blood pressure). By using one or more physiological sensors, the pulsatile flow can be synchronized with the patient's cardiac cycle by, for example, monitoring blood pressure or muscle contraction and synchronizing the duty cycle according to the sensed output.

[0106] The controller 30 may compare the physiological sensor measurements to the current pump output. If it is determined by analyzing the sensor measurements that the demand exceeds the current output, the frequency, amplitude and / or duty cycle may be automatically adjusted to meet the current demand. Similarly, the controller may determine that the current output exceeds the demand and therefore modify the output by changing the frequency, amplitude and / or duty cycle. Alternatively or in addition, an alarm may be issued from the controller 30 when it is determined that the demand exceeds the current output. Similarly, the operational measurements from the operational sensors may be compared to predetermined thresholds and an alarm may be issued from the controller 30 if the measurements exceed the predetermined thresholds or a fault is detected.

[0107] The pump 20 is sized and shaped to produce physiological flow rates, pressure gradients, and pulsatility at an operating point that achieves maximum efficiency. In particular, the pump 20 may be sized and shaped to produce a physiological flow rate in the range of 2 to 15 liters per minute at a pressure gradient below a threshold associated with hemolysis. Moreover, to mimic a typical physiological pulse of 60 times per minute, the pump 20 may pulse approximately once per second. To achieve such pulsatility, a 20% to 50% duty cycle may be utilized, having an "on" or "high" period of 0.2 to 0.5 seconds and an "off" or "low" period of 0.5 to 0.8 seconds, for example, where the "high" setting represents an operating point that results in a frequency and amplitude of an increased blood flow rate relative to the physiological pressure, while the "low" setting represents an operating point that results in a frequency and amplitude of a lower blood flow rate relative to the physiological pressure. For a given system, maximum efficiency at a particular operating frequency, amplitude, and voltage can be achieved while producing a flow rate of 2 to 15 liters per minute at a duty cycle of 20% to 50% by manipulating one or more of the shape and size of the blood flow channel, the elastic properties of the suspension ring, the mass of the moving parts, the membrane geometry, and the elastic and frictional properties of the membrane. In this way, the pump 20 can be designed to produce a desired physiological output while continuing to operate at optimal operating parameters.

[0108] By adjusting the duty cycle, the pump 20 can be configured to produce a wide range of output flow rates under physiological pressure gradients. For example, for an exemplary LVAD system configured to produce 2 to 15 liters per minute at a duty cycle of 20% to 50%, the optimal operating frequency may be 25 to 70 Hz or even 120 Hz. For this system, for example, by changing only the duty cycle, the flow output may be increased to 10 liters per minute or decreased to 4 liters per minute. Since the duty cycle and frequency operate independently of each other, the duty cycle may be manipulated between 0 and 100% without affecting the frequency.

[0109] The pump systems described herein, tuned to achieve physiological flow rates, pressure gradients, and pulsatility, also avoid hemolysis and platelet activation by applying low to moderate shear forces on the blood, similar to the shear forces encountered by blood elements in a normal, disease-free vascular system. In the embodiments detailed above, the delivery channel 100 can be sized and configured to also avoid friction between the moving magnetic ring assembly 76, suspension rings 79 and 80, posts 81, and lower housing portion 25 by sizing the channel so that at least 0.5 mm of clearance is maintained between all moving components. Similarly, the magnetic ring assembly 76, suspension rings 79 and 80, and posts 81 are all offset from the stator assembly 72 by at least 0.5 mm to avoid friction between the stator assembly and the moving parts.

[0110] Reference now Fig.15A and 15B , describes an alternative exemplary embodiment of the pump assembly of the present invention. The construction of the pump 20' is similar to Figure 7 , 8 12 and 13 , wherein like components are identified with like numerals. Pump 20′ differs from pump 20 in that membrane assembly 82′ includes a skirt 115 coupled to membrane 97′. The skirt illustratively includes a first portion 115a and a second portion 115b. The first portion 115a of the skirt 115 extends upwardly in a first direction toward the inlet 21′ within the delivery channel 100′, for example, parallel to the longitudinal axis of the stator assembly 72′ and / or the central axis of the pump housing 27′. The second portion 115b of the skirt 115 is bent toward the outlet 23′ so that the second portion 115b is coupled to the membrane 97′ so that the membrane 97′ is oriented in a second direction, for example, perpendicular to the first portion 115a of the skirt 115. For example, the skirt 115 may have a J-shaped cross-section such that the first portion 115a forms a cylindrical ring around the stator assembly 72' and the second portion 115b has a predetermined radius of curvature that allows blood to flow smoothly from the delivery channel 100' across the skirt 115 to the outer edge of the membrane 97' and into the flow channel 101' while reducing stagnation of blood flow. The skirt 115 interrupts blood flow recirculation within the delivery channel 100' and increases the hydraulic power generated for a given frequency while minimizing blood damage. In addition, the J-shape of the skirt 115 around the stator assembly 72' can be stiffer than a flat rigid membrane ring, thereby reducing flexing and fatigue, as well as resistance to blood moving across the membrane 97'.

[0111] The skirt 115 exhibits rigid properties under typical forces experienced during the entire operating range of the present invention and can be made of a biocompatible metal (e.g., titanium). The skirt 115 is preferably impermeable so that blood cannot flow through the skirt 115. The post receiving position 98' can be formed into the skirt 115 to engage the membrane assembly 82' with the post 81'. Alternatively, the post 81' can be attached to the skirt 115 in any other manner that transfers the movement of the magnetic ring assembly 76' to the skirt 115.

[0112] As the magnetic ring assembly 76' moves up and down, the movement is rigidly transferred by the post 81' to the J-shape of the skirt 115 of the membrane assembly 82'. Taking into account the rigidity of the post, when the magnetic ring assembly 76' moves a certain distance up or down, the membrane assembly 82' can move the same distance. For example, when the magnetic ring assembly 76' moves 2mm from a position near the first electromagnetic coil 77' to a position near the second electromagnetic coil 78', the membrane assembly 82' can also move 2mm in the same direction. Similarly, the frequency at which the magnetic ring assembly 76' traverses the space between the first and second electromagnetic coils can be the same as the frequency at which the membrane assembly 82' moves the same distance.

[0113] The skirt 115 may be attached to the membrane 97' and hold the membrane 97' taut. The membrane 97' may be molded directly onto the skirt 115 or may be attached to the skirt 115 in any manner that keeps the membrane 97' uniformly taut along its circumference. For example, the skirt 115 may be coated with the same material used to form the membrane 97', and the coating on the skirt 115 may be integrally formed with the membrane 97'.

[0114] Blood may enter the pump 20' from the left ventricle through the inlet cannula 21' and flow down the pump assembly into the delivery channel 100'. As the blood moves down the tapered section 83', it is directed through the gap 74' and into the vertical portion of the delivery channel 100' in the area between the pump housing 27' and the actuator assembly 95'. Fig.15A, the skirt 115 divides the delivery channel 100' into an upper delivery channel 100a and a lower delivery channel 100b, so that the blood flow through the delivery channel 100' is divided into a flow channel 101a through the upper delivery channel 100a and a flow channel 101b through the lower delivery channel 100b, wherein the flow channels 101a and 101b are separated by the membrane 97'. As will be understood by those of ordinary skill in the art, the volume of blood passing through each of the delivery channels 100a and 100b may depend on the diameter of the first portion 115a of the skirt 115. For example, the larger the diameter of the first portion 115a of the skirt 115, the larger the volume of the delivery channel 100a, and the smaller the volume of the delivery channel 100b. The ratio of the volume of the delivery channel 100a to the volume of the delivery channel 100b may be, for example, 1:1, 1:2, 1:3, 1:4, 2:1, 3:1, 4:1, etc., depending on the blood flow rate required on each surface of the membrane 97'.

[0115] By directing blood from the inlet cannula 21' across the skirt 115 within the delivery channel 100', the blood flow is divided into the delivery channels 100a and 100b and flows to the flow channels 101a and 101b respectively, so that the blood flows across the upper and lower surfaces of the membrane 97' of the membrane assembly 82'. Fig.16A , blood flow through a pump having a planar rigid membrane ring spaced a relatively small distance from the pump housing can allow unrestricted blood flow across the upper surface of the flexible membrane while restricting blood flow across the lower surface of the flexible membrane. Fig. 16B and 16C As depicted in FIG. 1 , blood flow through a pump having a J-shaped skirt or integrated portion can be distributed across the upper and lower sides of the flexible membrane in a desired ratio.

[0116] The second portion 115b of the skirt 115 is bent toward the outlet 23' so that the second portion 115b is coupled to the membrane 97' so that the membrane 97' is oriented in a second direction, such as perpendicular to the first portion 115a of the skirt 115. For example, the skirt 115 may have a J-shaped cross-section so that the first portion 115a forms a cylindrical ring around the stator assembly 72' and the second portion 115b has a predetermined radius of curvature that allows blood to flow smoothly from the delivery channel 100' across the skirt 115 to the outer edge of the membrane 97' and into the flow channel 101' while reducing stagnation of blood flow. The skirt 115 interrupts the recirculation of blood flow within the delivery channel 100' and increases the hydraulic power generated for a given frequency while minimizing blood damage. In addition, the J-shape of the skirt 115 around the stator assembly 72' can be stiffer than a flat rigid membrane ring, thereby reducing flexing and fatigue, as well as resistance to blood moving across the membrane 97'.

[0117] Return to reference Fig.15ABy actuating the electromagnetic coils 77' and 78', the membrane 97' can fluctuate within the flow channels 101a and 101b to cause wave formation in the membrane 97' that moves from the edge of the membrane 97' toward the circular hole 99'. Therefore, when blood is delivered from the delivery channel 100' to the membrane assembly 82', it can be radially pushed along both the upper and lower surfaces of the membrane 97' toward the circular hole 99' and exit the outlet 23' therefrom. The blood flow distribution across the upper and lower surfaces of the membrane 97' reduces the recirculation of blood within the delivery channel 101' and reduces repeated exposure of blood to high shear stress areas, which results in a significant improvement in the hydraulic performance of the pump 20'.

[0118] Reference now Fig. 16C , illustrating a pump 400 that is similar to the pump 20 and includes a pump housing 402, an integrated assembly 406, a membrane 416, and an actuator assembly 404, which may be the same or similar to the actuator assembly 95. The integrated assembly 406 may be disposed around the actuator assembly 404 and may include a magnetic assembly 408 and a transition portion 410. The magnetic assembly 408 may be similar to the magnetic ring assembly 76 and / or may include one or more magnets 422 and / or an iron portion 420. It should be understood that the magnetic assembly 408 may include a Halbach array. The integrated assembly 406 may further include an outer cover 418 to allow for hermetic sealing of components in the integrated assembly 406 (e.g., the magnetic assembly 408) and a magnet backing 424 to facilitate magnet alignment and assembly. The integrated assembly 406 may also include one or more bearing portions 419.

[0119] The integrated assembly 406 may be similar in function to the skirt 115, except that the integrated assembly 406 may incorporate the magnetic assembly 408. The integrated assembly 406 may extend upward within the delivery channel 405, and further include a transition portion 410 extending toward a membrane 416, which may be the same as or similar to the membrane 97. The transition portion 410 may attach the integrated assembly 406 to the membrane 416. The integrated assembly 406 may define a first blood channel 412 between the integrated assembly 406 and the pump housing 402, and may further define a second blood channel between the integrated assembly 406 and the actuator assembly 404. Similar to the skirt 115, the integrated assembly 406 may transfer blood into the first blood channel 412 and the second blood channel 414, and ultimately to the membrane 416.

[0120] The pump housing 402 may include one or more magnets 413 and one or more bearing portions 417. The bearing portion 417 may be in fluid communication with the bearing portion 419 (e.g., via blood in the first blood channel 412), and together may form a bearing that resists radial movement of the moving assembly 406. The bearing portions 417 and 419 may include biocompatible materials such as ceramics, alumina, zirconium oxide, or zirconium oxide toughened alumina, or engineered plastics such as polyetheretherketone (PEEK) and Delrin, or metal alloys coated with friction coatings such as titanium coated with titanium nitride (TiN) or zirconium nitride (ZrN). The magnets 413 and the magnetic assembly 408 may interact to resist axial movement and return the moving assembly axially to a neutral position.

[0121] One or more magnets of the magnetic assembly 408 may be enlarged to add the second blood channel 414 while maintaining an attractive force between the one or more coils (e.g., coil 411) of the actuator assembly 404 and the magnetic assembly 408. Adding the second blood channel 414 may reduce the risk of shear-induced damage and / or thermal damage to the blood. Fig. 16C 4. As shown in FIG. 4, in addition to the membrane 416, the pump 400 may also have a single moving assembly (eg, integrated assembly 406).

[0122] Reference now Fig.16D, illustrating a pump 450 including an inlet spring 458 and an outlet spring 460. Pump 450 may be similar to pump 400, and may include an actuator assembly 452 (which may be similar to actuator assembly 404), a pump housing 456 (which may be similar to pump housing 402), and an integrated assembly 454 (which may be similar to integrated assembly 406). As shown in FIG. 16, integrated assembly 454 may be coupled to inlet spring 458 and outlet spring 460. Inlet spring 456 and outlet spring 460 may be coupled to integrated assembly 454 at one end and to pump housing 456 at the other end. For example, inlet spring 458 and outlet spring 460 may be integral springs or any other well-known springs. Inlet spring 458 and outlet spring 460 may include biocompatible metals such as, for example, stainless steel, titanium, or cobalt chromium, and / or may be treated to increase durability and blood compatibility by methods of removing surface defects or cold working the material. The inlet spring 458 and / or outlet spring 460 can be made by cutting shapes from a flat plate of biocompatible metal. Alternatively, the inlet spring 458 and / or outlet spring 460 can be machined from a solid block of material, thus allowing for a more contoured and / or three-dimensional design. In a preferred embodiment, the solid block of material is stainless steel or titanium. The inlet spring 458 and outlet spring 460 can resist both radial and axial movement of the moving assembly 456 and can return the moving assembly 456 to a neutral position. It should be understood that the inlet spring 458 and / or outlet spring 460 can be optional (for example, the pump 450 can include the inlet spring 458 and / or outlet spring 460). Also as Fig.16D , damping structure 462 may be coupled to and / or extend from actuator assembly 452 and may facilitate damping vibrations of pump 450 (e.g., caused by moving assembly 454). Damping structure 462 may include, for example, a polymer material having a Shore hardness value of 20 to 80A, such as a biocompatible polyurethane. It should be understood that inlet spring 458 and outlet spring 460 may be the same or similar to suspension springs. Alternatively, an active damping structure may be used. The active damping structure may include or otherwise employ one or more moving masses or tuned mass dampers to reduce vibrations. In one example, the active damping structure may be positioned on an outer surface of the pump, such as Fig.17 Vibration damping assembly 523 in.

[0123] Reference now Fig.17 , illustrating a pump 500 having a packaging assembly. The pump 500 is similar to the pump described above with respect to Figure 7 , 812. For example, the pump 500 may include an inlet cannula 501 (which may be similar to the inlet cannula 21), an outlet cannula 502 (which may be similar to the outlet cannula 22), an upper housing portion 515 (which may be similar to the upper housing portion 24), and a lower housing portion 517 (which may be similar to the lower housing portion 25). The upper housing portion 515 may be coupled to the lower housing portion 517 and the outlet cannula 502. The lower housing portion 517 may be coupled to the outlet cannula 502. The upper housing portion 515 and / or the inlet cannula 501 may be coupled to a stator assembly 511, which may include an upper stator portion 521 and a lower stator portion 520, and a core stator portion 545. The core stator portion 545 may be coupled to both the upper stator portion 521 and the lower stator portion 520, and may support electromagnetic coils (e.g., the first electromagnetic coil 504 and the second electromagnetic coil 505).

[0124] like Fig.17 , the upper stator portion 521 and the lower stator portion 520 can form a stator assembly 511 and can be designed to accommodate and fix an electromagnetic assembly 503, which can be similar in structure and / or function to the electromagnetic assembly 91. For example, the electromagnetic assembly 503 can include a first electromagnetic coil 504 and a second electromagnetic coil 505. It should be understood that the electromagnetic assembly 503 can be any electromagnetic assembly described herein and / or can include more or less than two electromagnetic coils. The electromagnetic assembly 503 together with the stator assembly 511 forms an actuator assembly.

[0125] A magnetic assembly 513, which may be similar in structure and function to the magnetic ring assembly 76, may be suspended around the electromagnetic assembly 503. For example, the magnetic assembly 513 may be Fig.19 . The magnetic assembly 513 may also be coupled to a first spring 534 (which may be similar to the first suspension spring 79) and a second suspension spring 535 (which may be similar to the second suspension spring 80). The first suspension spring 534 may also be coupled to the upper stator portion 521, and the second suspension spring 535 may also be coupled to the lower stator portion 520. The first suspension spring 534 and the second suspension spring 535 may bias the magnetic assembly 513 toward a neutral position between the first suspension spring 534 and the second suspension spring 535 and / or may offset the magnetic assembly 513 from the actuator assembly 503. It should be further understood that the first suspension spring 534 and the second suspension spring 535 may resist torsional and / or tilting movement of the magnetic assembly 513 and / or provide a restoring force to return the magnetic assembly 513 toward a center position. In particular, the first suspension spring 534 and the second suspension spring 535 may help keep the axial centerline of the stator parallel to the magnetic ring.

[0126] The upper stator portion 521 may be further coupled to a top encapsulator 532, and the lower stator portion 520 may be coupled to a bottom encapsulator 531. The top encapsulator 532 and the bottom encapsulator 531 may each be coupled to the magnetic assembly 513. The top encapsulator 532 and the bottom encapsulator 531 may be elastic membranes made of any well-known elastic or expandable material and / or structure. For example, the top encapsulator 532 and / or the bottom encapsulator 531 may be made of any well-known elastic and / or thermoplastic material and / or viscoelastic material (e.g., silicone) and / or any ridged material that forms a structure designed to expand (e.g., a metal structure with bellows). The top encapsulator 532 and the bottom encapsulator 531 may exert a spring force on the magnetic assembly 513 due to the elastic properties of each. The top encapsulator 532 and the first suspension spring 534 can work together to jointly apply a spring force to the magnetic assembly 513, and similarly, the bottom encapsulator 531 and the second suspension spring 535 can work together to apply a spring force to the magnetic assembly 513. The first suspension spring 534 and / or the second suspension spring 535 can be sized and otherwise designed to accommodate the spring force of the top encapsulator 532 and / or the bottom encapsulator 531. For example, the first suspension spring 534 and / or the second suspension spring 535 can be sized and otherwise shaped to achieve a desired neutral position of the magnetic assembly 513 based at least in part on the elastic properties of the top encapsulator 532 and the bottom encapsulator 531.

[0127] The magnetic assembly 513, the top and bottom encapsulators 532 and 531, and the stator assembly 511 may together form a packaging assembly 525, which may form a continuous surface, thereby packaging the actuator assembly 503, the first suspension spring 534, and the second suspension spring 535. In this way, a blood flow channel 537 may be defined between the magnetic assembly 513, the top and bottom encapsulators 532 and 531, and the stator assembly 511 (i.e., the packaging assembly 525) on one side, and between the inner surfaces of the upper housing portion 515 and the lower housing portion 517 on the other side.

[0128] The encapsulation assembly 525 can present a number of advantages. For example, because the actuator assembly 503, the first suspension spring 534, and the second suspension spring 535 are encapsulated, the blood is prevented from interacting with the actuator assembly 503, the first suspension spring 534, and the second suspension spring 535, and thus such encapsulation can prevent damage to the blood (e.g., hemolysis) that can occur when these components interact with the blood and the magnetic assembly 513 during operation of the pump 500. Moreover, from a fluid dynamics point of view, the blood path can be smoother, with fewer areas with stagnation and turbulence, thereby reducing the risk of thrombosis. The blood path can be optimized to minimize exposure of the blood to shear conditions, which can cause damage to blood elements (e.g., adhesion proteins, von Willebrand factor).

[0129] The membrane assembly 538 can be coupled to the magnetic assembly 513 so that the membrane assembly 538 moves with the magnetic assembly 513. The membrane assembly 538 can include a skirt 550 and a membrane 507, which can be similar to the skirt 115 and the membrane 97', respectively, as described above with respect to Fig. 16B Description. Membrane 507 may be circular and may include a circular hole in the center. For example, skirt 550 may be disposed around packaging assembly 525 and may extend in a vertical direction within delivery channel 537 and may bend toward membrane 507, which may be oriented in a horizontal direction. For example, skirt 550 may have a J-shaped cross-section such that a portion of skirt 550 forms a cylindrical structure around stator assembly and may have a predetermined radius of curvature that allows blood to flow smoothly from delivery channel 537 across skirt 550 to membrane 507, thereby reducing stagnation of blood flow.

[0130] The skirt 550 can reduce or eliminate blood recirculation within the delivery channel 537 and increase the hydraulic power generated for a given frequency while minimizing blood damage. In addition, the J-shape of the skirt 550 can be stiffer than the membrane 507, thereby reducing flexing and fatigue, as well as resistance to blood moving across the membrane 507. The membrane assembly 538 can be rigidly coupled to the magnetic assembly 513 via a plurality of rigid pins and / or via weldable surface contacts. When the magnetic assembly 513 moves up and down (e.g., reciprocating), the skirt 550 will also do so, thereby inducing wave-like fluctuations in the membrane 507, which push the blood above and below the membrane 507, thereby separating the blood flow path 537 including the blood flow path 506 toward the outlet cannula 502 of the pump 500.

[0131] The upper housing portion 515 may include a vibration damping assembly 523, which may be designed to dampen vibrations of the pump 500 when the magnetic assembly 513 reciprocates in operation. For example, the vibration damping assembly 523 may be a tuned mass damper, in which the mass is tuned to oscillate 180 degrees in phase with the primary motion of the actuator. The vibration damping assembly 523 may include a mass 540 suspended by one or more vibration springs 541. For example, the mass 540 may be an annular mass. The vibration damping assembly 523 may be disposed around and / or positioned on the outer surface of the upper housing portion 515, or otherwise incorporated into the upper housing portion 515. The mass 540 and the vibration springs 541 may be sized and shaped to reduce the vibration level of the pump 500 due to the reciprocation of the magnetic assembly 513.

[0132] Reference now Fig.18 , illustrating an exploded view of the actuator assembly, magnetic assembly, and membrane assembly. Fig.18 As shown in FIG. 1 , the inlet block 601 may include an inlet cannula 621 (which may be similar to Fig.17 The inlet cannula 501 of FIG. 501 and the upper stator portion 622 (which may be similar to Fig.17 The first suspension spring 603 (which may be similar to Fig.17 The first suspension spring 534) can be coupled to the upper stator portion 622.

[0133] The core assembly 602 can be coupled to the upper stator portion 622 and can be disposed below the first suspension spring 603. The core assembly 602 can include an electromagnetic assembly 605 (which can be similar to Fig.17 The actuator assembly 503) and the core stator portion 624 (which can be connected to Fig.17 The core stator portion 624 may support the electromagnetic assembly 605. The core assembly 602 may include an encapsulation portion 626, which may be a flexible film (e.g., silicone) that may cover all or a portion of the electromagnetic assembly 605 and / or the core stator portion 545. The magnetic assembly 607 (which may be similar to Fig.17 The magnetic assembly 513 of the core assembly 602 can be disposed around the core assembly 602 and can be coupled to the inlet block 601 via the first suspension spring 534. The magnetic assembly 607 can include a pin receiving portion 619 sized and designed to receive and engage the pin 615.

[0134] The second suspension spring 609 (which may be similar to Fig.17 The second suspension spring 535 of the embodiment of the present invention may also be coupled to the magnetic assembly 607 and also coupled to the lower stator portion 611 (which may be similar to Fig.17607 can be concentrically positioned between the first suspension spring 603 and the second suspension spring 609 so that the magnetic assembly 607 can oscillate between the first suspension spring 603 and the second suspension spring 609. The first suspension spring 603 and the second suspension spring 609 can be further coupled to the core assembly 602. The lower stator portion 611 can further include a protrusion 628 that can extend upward relative to the lower stator portion 611. For example, the protrusion 628 can extend through the core stator portion 624 and engage the upper stator portion 622 to couple the lower stator portion 611 and the core stator portion 624 to the upper stator portion 622. In one example, the engagement between the protrusion 628 and the upper stator portion 622 can be a threaded engagement.

[0135] The membrane assembly 645 may include a skirt 613 and a membrane 640. The skirt 613 may be similar to Fig.17 The skirt 550 and the membrane 640 may be similar to Fig.17 The skirt 613 may further include a plurality of pin receiving portions 617, which may be holes extending through the skirt 613 and may be sized and shaped to receive pins 615. The pins 615 may be any type of well-known pins that may extend through the skirt 613 and couple the skirt 613 to the magnetic assembly 607. In this manner, the membrane assembly 645 may be rigidly coupled to the magnetic assembly 607. It should be understood that the magnetic assembly 607 may alternatively be coupled to the skirt 613 using any other well-known coupling techniques (e.g., adhesives, threaded engagement, etc.).

[0136] Reference now Fig.19 , explaining the magnetic ring assembly 700. Fig.19 , the magnetic ring assembly 700 may include magnet 701, magnet 705, and magnet 709, each of which may include one or more magnet portions forming a ring and / or having a general radius of curvature. It should be understood that the magnet portions 701, 705, and 709 may include one or more magnets and / or iron portions (e.g., iron cobalt). In an embodiment, the magnetic portions 701, 705, and 709 are iron cobalt. In an embodiment, the magnetic ring assembly 700 may include three magnets such as iron, neon, and / or boron, which have an iron back cover of iron cobalt. It should be further understood that the magnetic portions 701, 705, and / or 709 may be or include a Halbach array. The magnetic ring assembly 700 may further include an inner housing 706, which may contain or otherwise support the moving magnet portions 701, 705, and 709. The outer housing 707 may be disposed over the inner housing 706 and the magnet portions 701, 705, and 709, and may be coupled to the inner housing 706 to secure and seal the magnet portions 701, 705, and 709 to the inner housing 706. Fig.19700, but it should be understood that more or fewer magnet sections may be included in the magnetic ring assembly 700. It should be understood that the magnetic ring assembly 700 may include magnetic segments arranged in series, such as the magnet sections 701, 705, and 709. Alternatively, the magnetic ring assembly 700 may include a single continuous cylindrical magnet or a series of magnets.

[0137] Figures 20A to 20C Pump 800, packaging assembly 850, and membrane assembly 817 are illustrated. Fig. 20A , the packaging assembly 850 can be Fig.17 Specifically, the packaging assembly 850 may include an upper stator assembly 801, a top packager 815, a magnetic assembly 805, a bottom packager 816, and a lower stator assembly 803, which may be similar to Fig.17 805. The upper stator portion 521, the top encapsulator 519, the magnetic assembly 513, the bottom encapsulator 521, and the lower stator portion 520. The upper stator assembly 801 can be coupled to the inlet cannula 855. The magnetic assembly 805 can include a pin receiving portion 821.

[0138] like Fig. 20A , the magnetic assembly 805 can be positioned between and coupled to the top encapsulator 815 and the bottom encapsulator 816. The top encapsulator 815 can engage the upper stator portion 801. The encapsulation assembly 850 can be coupled to the membrane assembly 817 (which can be similar to Fig.17 The membrane assembly 538) is axially and concentrically aligned. For example, the membrane assembly 817 may include a skirt 807 and a membrane 818, which may be similar to Fig.17 Skirt 550 and membrane 507.

[0139] Fig. 20B 817 can be positioned concentrically around and offset from the magnetic ring assembly 805. Fig. 20B , the membrane assembly 817 can be rigidly coupled to the magnetic ring assembly 805 via a pin 811, which can extend through the membrane assembly 817 and engage the magnetic ring assembly 805. Referring now to Fig. 20C , illustrating the connection between the membrane assembly 817 and the magnetic assembly 805. Fig. 20C , the film assembly 817 can include a hole 820 through which the pin 811 can be inserted to engage with a pin receiving portion 821 of the magnetic assembly 805 , the pin receiving portion 821 being sized and designed to receive the pin 811 .

[0140] Reference now Figures 21A to 21C , illustrating the movement of the membrane 901 during the operation of the pump. Fig.21AAs shown in FIG. 1 , the magnetic assembly 903 (which may be similar to Fig.17 513) has moved to the uppermost position relative to stator assembly 909 (which may be similar to stator assembly 511). As a result, membrane assembly 907 (which may be similar to membrane assembly 538) may also move upward, thereby causing membrane 901 (which may be similar to membrane 507) to move upward. However, when membrane assembly 907 moves upward, independent portion 905 of membrane 905 may remain in a lower position. Fig. 21B and Fig. 21C , the membrane assembly 907 can be moved downward to the second and third positions, respectively, wherein a portion of the membrane 901 (the independent end 901) rises and the membrane assembly 907 falls. In this way, a wave-like undulation toward the independent end 905 can be generated, which pushes the blood to the independent end 905. This process is repeated, and the membrane 901 moves upward back to the second and third positions. Fig.21A , and then move again to the first position shown in Fig. 21B and 21C The second and third positions are shown in the figure.

[0141] Reference now Fig.22A and Fig. 22B , the pump 1000 may be similar to Fig.17 Pump 500. Fig.22A , pump 1000 may include packaging assembly 1001, upper housing portion 1002, lower housing portion 1003, and membrane assembly 1004, which may be similar to packaging assembly 525, upper housing portion 515, lower housing portion 517, and membrane assembly 535. Packaging assembly 1001 on one side and upper housing portion 1002 and lower housing portion 1003 on the other side may form blood flow path 1005. Fig.22A , blood may enter the components shown in red, and thus may enter the inlet cannula 1006 , travel along the membrane assembly 1004 in the blood flow path 1005 , and exit the outlet cannula 1007 .

[0142] Fig. 22B 1 is a top view of pump 1000 depicting packaging assembly 1001, membrane assembly 1004, and a portion of upper housing portion 1002. Fig. 22B , the blood path 1005 is defined by the inner surface of the packaging assembly 1001 and the upper housing portion 1002, and is divided into two blood flow paths by the membrane assembly 1004. The upper housing portion 1002 may further include a positioning sensor 1008, which can determine certain operational information about the position of the pump and / or membrane assembly 1005.

[0143] exist Fig.23 The membrane assembly 1004 is described in more detail in FIG. Fig.23, the membrane assembly 1004 can include one or more sensor targets 1301. The sensor target 1301 can be a permanent magnet that is a target for a sensor mounted on the outside of the pump housing and can create a moving field for the sensor. The sensor target 1301 can be connected to Fig. 22B 1301. The membrane assembly 1004 may be used together with the positioning sensor 1008 described in the figure to determine information about the position of the membrane assembly 1004 relative to the pump. Such information can be used to control the movement of the membrane in a closed-loop circuit, thereby widening the operating range and preventing excessive amplitudes that may damage the spring. In one embodiment, the sensor target may be similar to such a structure further described in detail in U.S. Pat. No. 10,799,625, which is incorporated herein by reference. The membrane assembly 1004 may include one or more sensor receiving portions 1303 that may be sized and shaped to receive the sensor target 1301. The sensor receiving portion 1303 may be sealed with a sealing portion 1302, which may cover the sensor receiving portion 1303 and the sensor target 1301.

[0144] Reference now Fig.24 , illustrates a cross-sectional view of a pump 1100 having various isolated portions. The pump 1100 may be similar to Fig.17 1. The pump 500 of FIG. 1 may include a stator assembly 1103, an electromagnetic assembly 1108, a magnetic assembly 1107, a top encapsulator 1109, and a bottom encapsulator 1111, and an encapsulation assembly 1113. The magnetic assembly 1107 may include an isolation portion 1124, which may include gaps and / or empty spaces in the magnetic assembly 1107 that may be filled with epoxy backfill 1124. The electromagnetic assembly 1108 may similarly include an isolation portion 1126, which may include gaps and / or empty spaces in the electromagnetic assembly 1108 that may be filled with epoxy backfill. Such epoxy backfill of the isolation portions 1124 and 1126 may protect metal components and / or wires and / or provide a locking feature to prevent unscrewing. The epoxy backfill may be added under vacuum before sealing the subassembly. For example, the actuator assembly 1106 , which may include the core stator portion 1104 and the electromechanical assembly 1108 , may be hermetically sealed (eg, by a welded joint). The core stator portion 1104 may support the electromechanical assembly 1108 .

[0145] Reference now Fig.25 , a perspective view of the actuator assembly 1106 is shown. Fig.25 , the actuator assembly 1106 may include a number of grooves 1130 positioned on the outer surface of the actuator assembly 1106. The grooves 1130 may be sized and arranged to prevent eddy currents from circulating in the stator. The grooves 1130 may also provide a wiring path for connecting to the coils. Fig.25, a wire path 1132 is shown in one of the circular grooves for connection to the coil. The groove 1130 can be sized to facilitate backfilling of the stator from the inner diameter, which can be used to get epoxy into the outer diameter of the actuator assembly.

[0146] Reference again Fig.24 , the isolation portion 1122 can be filled with a packaging fluid. For example, the packaging fluid can be a perfluorocarbon, such as perfluorodecalin. For example, the isolation portion 1122 can be defined by the space between the actuator assembly 1106 and the stator assembly 1125, the top encapsulator 1109, the magnetic assembly 1107, and the bottom encapsulator 1111. The packaging fluid can be an inert fluid that prevents the migration of air, water, and other dissolved components. The packaging fluid can be silicone oil, saline, and / or deionized water. The packaging fluid can be added to the pump 1100 by the following process. First, a two-way faucet can be connected to the pump 1100 (for example, through an inlet block). Then, the pump core can be placed under vacuum as a connector that can switch to a liquid path. Once the packaging fluid has filled the isolation portion 1122, the chamber pressure can be returned to atmospheric pressure. Then, the sealed package backfill inlet.

[0147] Reference now Fig.26A and Fig.26B , the entry block 1400 may be similar to Fig.18 The entry block 601 in. Fig.26A , the inlet block 1400 may include at least a portion of the stator assembly and an inlet cannula 1402. For example, the inlet block 1400 may include a stator joint 1406 for engaging the stator assembly. The stator joint 1406 may be a threaded joint. The inlet block 1400 may further include a number of dividers 1404 positioned near the bottom of the inlet cannula 1402 that create a mechanical connection between the actuator and the housing. Fig.26B (which is a top view of inlet block 1400), blood can enter the pump through inlet cannula 1402. The shape of divider 1404 can be designed to prevent flow stagnation to reduce the risk of thrombosis. As blood traverses inlet block 1400, it can be divided into various blood flow paths by divider 1404. Inlet block 1400 can include channels for electrically connecting the actuator assembly to the outside of the pump and / or channels for filling cavity 1122, such as Fig.24 Displayed in.

[0148] Reference now Figures 27A to 27B , illustrating pump 1500. Pump 1500 may be similar to Fig.17For example, the pump 1500 may include an inlet cannula 1502, a stator assembly 1507, a top encapsulator 1510, a magnetic assembly 1511, a bottom encapsulator 1514, an electromagnetic assembly 1512, an upper housing portion 1503, a lower housing portion 1505, a membrane assembly 1509, and an outlet cannula 1515, which may be similar to the above-mentioned components. Fig.17 The inlet cannula 501, stator assembly 511, top package 532, magnetic assembly 513, bottom package 531, electromagnetic assembly 503, upper housing portion 515, lower housing portion 517, membrane assembly 538 and outlet cannula 502 are described. Fig.27A As shown in FIG. 1 , the elastic properties of the top package 1510 and the bottom package 1514 can provide a spring function to return the actuator to the center position. Fig.27B , the pump housing 1500 can include one or a bearing portion 1517. The bearing portion 1517 can resist radial movement of the magnetic assembly 1511 within the pump 1500.

[0149] Reference now Fig.28 , illustrating a pump 1600, and which may include a top package 1603 and a bottom package 1610, each of which may include a bellows. The pump 1600 may be similar to Fig.17 For example, the pump 1600 may include an inlet cannula 1610, a stator assembly 1604, a magnetic assembly 1602, a bottom packager 1610, an electromagnetic assembly 1605, an upper housing portion 1611, a lower housing portion 1612, and a membrane assembly 1613, which may be similar to the components including Fig.17 The inlet cannula 501, the stator assembly 511, the magnetic assembly 513, the electromagnetic assembly 503, the upper housing portion 515, the lower housing portion 517 and the membrane assembly 538. The top package 1603 and the bottom package 1610 can be similar to Fig.17 1603 and the bottom package 1610, however, the top package 1603 may include a bellows 1614 and the bottom package 1610 may include a bellows 1615. For example, the top package 1603 and the bottom package 1610 may be formed of one or more well-known metals or metal alloys, and the bellows 1614 and 1615 may be corrugated bellows. In this way, the top package 1614 and the bottom package 1614 may be made of metal, but still be flexible and facilitate the movement of the magnetic assembly 1602.

[0150] Reference now Figures 29A to 29B , illustrating a pump 1700 including a flexure spring 1710 attached to an actuator compartment 1716. The pump 1700 may be similar to Fig.17For example, the pump 1700 may include an inlet cannula 1701, a stator assembly 1702, a top package 1704, a magnetic assembly 1705, a bottom package 1706, an electromagnetic assembly 1708, and a membrane assembly 1738, which may be similar to the pump 1700 that includes Fig.17 The inlet cannula 501, the stator assembly 511, the top packager 532, the magnetic assembly 513, the bottom packager 531, the electromagnetic assembly 503 and the membrane assembly 538.

[0151] The membrane assembly 1738 may be coupled to the magnetic assembly 1705. The electromagnetic assembly 1708 may be positioned within an actuator compartment 1716, which may be a cylindrical or similarly shaped structure that serves as a physical connection between the magnetic ring and the flexure bearing, which may be porous. For example, the actuator compartment may be a thin-walled cylinder. The electromagnetic assembly 1708 may be isolated from the rest of the pump 1700 by the top encapsulator 1704 and the bottom encapsulator 1706. The actuator compartment 1716 may be connected to the stator assembly 1702 via one or more flexure (helical) springs 1701. In Fig.29B 17. The flexure spring 1710 is shown in more detail in FIG. The flexure spring 1710 may include a number of curved through cuts 1720 that achieve a spiral shape on the flexure spring 1710. The flexure spring 1710 may optionally include a number of actuator compartment engagement portions along the flexure spring 1710. The flexure spring 1710 may be connected to the stator assembly 1702 at the stator receiving portion 1723, and may be connected to the actuator compartment 1716 via the actuator compartment engagement portion 1722. The flexure spring 1710 may incorporate dimensions and material properties that allow it to provide a spring force. The actuator compartment 1716 may be coupled to the magnetic assembly 1705; in an embodiment, the actuator compartment 1716 and the magnetic assembly 1705 are flexibly connected by a flexure bearing. The flexure bearing may provide a restoring force and may resist radial movement.

[0152] Reference now Fig.29B , illustrating a perspective view of the flexure spring and actuator compartment. Fig.29B1705. As shown in FIG. 17 , the stator assembly 1702 can include a central component 1734, which can be cylindrical and can engage an upper flexure spring 1730 and a lower flexure spring 1732 (each of which can be similar to the flexure spring 1710). The upper flexure spring 1730 and the lower flexure spring 1732 can also each be coupled to an actuator compartment 1716, which can be rigidly coupled to the magnetic assembly 1705. The top package 1704 and the bottom package 1706 can each be coupled to the stator assembly 1702 and the magnetic assembly 1705. An electromagnetic assembly (not shown) can be disposed in the actuator compartment 1716, but can be rigidly connected to the central component 1734 so that the actuator compartment 1716 is free to move axially relative to the stator assembly 1702. A membrane assembly 1738 can be coupled to the magnetic assembly 1705.

[0153] When the magnetic assembly 1705 interacts with the electromagnetic assembly, the magnetic assembly 1705 can be reciprocated up and down relative to the stator assembly 1702. Since the actuator compartment 1716 can be rigidly coupled to the magnetic assembly 1705, the actuator compartment 1716 can similarly reciprocate. The upper flexure spring 1730 and the lower flexure spring 1732 can allow the actuator compartment 1716 to move in the axial direction, and the upper flexure spring 1730 and the lower flexure spring 1732 can return the actuator compartment 1716 and thus the magnetic assembly 1738 to a neutral position via the spring force in the upper flexure spring 1730 and the lower flexure spring 1732. The upper flexure spring 1730 and the lower flexure spring 1732 can further resist the torsion or tilting of the actuator assembly 1716 and the magnetic assembly 1705.

[0154] Although various illustrative embodiments of the present invention are described above, it will be apparent to those skilled in the art that various changes and modifications may be made in the embodiments without departing from the present invention. Fig. 9 The pump assembly 70 shown in FIG. 1 may have a different order and may include additional or fewer components of various sizes and configurations. The appended claims are intended to cover all such changes and modifications as fall within the true spirit and scope of the present invention.

Claims

1. A blood pump system, comprising: a housing having an inlet and an outlet configured for fluid communication with a patient's circulatory system; a membrane disposed within the housing; an actuator disposed within the housing, the actuator configured to reciprocate the membrane to pump blood; and a packaging assembly configured to package the actuator so that blood does not contact the actuator, the packaging assembly disposed within the housing and configured to define a flow channel between the housing and the packaging assembly, Wherein, during operation, blood enters the inlet, flows in the flow channel between the housing and the packaging assembly, and is pushed across the membrane to the outlet to pump the blood.

2. The blood pump system of claim 1, wherein the actuator further comprises a magnetic assembly.

3. The blood pump system of claim 2, wherein the magnetic assembly is annular.

4. The blood pump system of claim 2, further comprising at least one spring coupled to the magnetic assembly, wherein the packaging assembly is coupled to the magnetic assembly, and the at least one spring and the packaging assembly exert a spring force on the magnetic assembly.

5. The blood pump system of claim 1, wherein the packaging assembly reduces the risk of damaging the blood due to shear conditions.

6. The blood pump system of claim 1, wherein the flow channel is configured to minimize disruption of von Willebrand Factor multimers in the blood.

7. The blood pump system of claim 1, wherein the flow channel is sized and configured to facilitate blood flow toward the outlet and to inhibit blood flow toward the inlet.

8. The blood pump system of claim 1, wherein the flow channel is sized and configured to reduce the risk of shear conditions of the blood in the flow channel and reduce recirculation of the blood.

9. The blood pump system of claim 1, further comprising a packaging fluid disposed between the packaging assembly and the actuator.

10. The blood pump system of claim 9, wherein the encapsulating fluid is a perfluorocarbon.

11. The blood pump system of claim 9, wherein the encapsulating fluid is selected from one of silicone oil, saline, deionized water, or perfluorodecalin.

12. A blood pump system comprising: a housing having an inlet and an outlet, the outlet being designed to be in fluid communication with the patient's circulatory system; an actuator comprising an electromagnetic assembly configured to generate a magnetic field; the actuator assembly being disposed within the housing, a stator assembly coupled to the actuator; a magnetic assembly configured to reciprocate in response to the magnetic field; and a packaging assembly coupled to the magnetic assembly and the stator assembly, the packaging assembly together with the magnetic assembly and the stator assembly being designed to package the actuator; and a flexible membrane coupled to the magnetic assembly and configured to reciprocate in response to the magnetic assembly; Wherein, during operation, blood enters the inlet, flows between the inner wall of the housing and the magnetic assembly, between the stator assembly and the packaging assembly, and is pushed across the flexible membrane to the outlet.

13. The blood pump system of claim 12, wherein the stator assembly comprises an upper stator assembly and a lower stator assembly.

14. The blood pump system of claim 13, wherein the upper stator assembly and the lower stator assembly are each coupled to the magnetic assembly.

15. The blood pump system of claim 13, wherein the magnetic assembly is annular.

16. The blood pump system of claim 13, further comprising at least one spring coupled to the magnetic assembly.

17. The blood pump system of claim 12, wherein the packaging assembly reduces the risk of damaging the blood due to shear conditions.

18. The blood pump system of claim 17, wherein the packaging assembly and the housing define a flow channel.

19. The blood pump system of claim 18, wherein the flow channel is sized and configured to facilitate blood flow toward the outlet and to inhibit blood flow toward the inlet.

20. The blood pump system of claim 18, wherein the flow channel is configured to reduce recirculation of the blood.

21. A method of pumping blood using a blood pump, the method comprising: A blood pump is provided that is designed to be in fluid communication with a patient's circulatory system, the pump comprising: a housing having an inlet and an outlet; an actuator comprising an electromagnetic assembly designed to generate a magnetic field, the actuator assembly being disposed within the housing and comprising: stator assembly, and a magnetic assembly configured to reciprocate in response to the magnetic field; a packaging assembly coupled to the magnetic assembly and the stator assembly, the packaging assembly being designed to package the actuator; and a flexible membrane coupled to the magnetic assembly and configured to reciprocate in response to the magnetic assembly; and sending an electrical signal to the actuator to energize the electromagnetic assembly to generate the magnetic field; The magnetic field reciprocates the flexible membrane, thereby propagating waves along the flexible membrane, causing blood to move from the inlet between the inner wall of the housing and the magnetic assembly, stator assembly and packaging assembly, across the flexible member and out of the outlet.

22. A blood pump comprising: a housing having an inlet and an outlet and configured to be in fluid communication with a circulation system; Actuator, It is arranged in the housing, and the actuator comprises: an electromagnetic assembly configured to generate a magnetic field; an upper stator coupled to the electromagnetic assembly; a lower stator coupled to the electromagnetic assembly; and a magnetic assembly comprising at least one magnet, the magnetic assembly configured to reciprocate in response to the magnetic field; a first packaging portion coupled to the upper stator and the magnetic assembly; a second packaging portion coupled to the lower stator and the magnetic assembly; and a flexible membrane coupled to the magnetic assembly and configured to reciprocate in response to the magnetic assembly; The first packaging portion, magnetic assembly and second packaging portion encapsulate the actuator so that during operation, blood enters the inlet, flows between the inner wall of the housing and the first packaging portion, between the magnetic assembly and the second packaging portion, and is pushed across the flexible membrane to the outlet.

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