Systems and methods for generating blood flow with a blood pump including a membrane and an encapsulated actuator are described. 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 encapsulation portions that connect the magnetic assembly to the stator assembly. The magnetic assembly may further be coupled to a membrane assembly including a flexible membrane. The electromagnetic assembly may be selectively activated to cause the magnetic assembly to reciprocate, thereby causing the membrane assembly to reciprocate and inducing wavelike undulations in the flexible membrane to pump blood from an inlet to an outlet of the pump. The encapsulation portions may prevent blood from interacting with an interior moving portion of the pump thereby reducing the risk of hemolysis.

An implantable LVAD is provided that includes a pump shaped so as to define a pump chamber. The pump includes a tubular linear motor, which includes a magnetic piston, which includes a reciprocating one-way valve configured to allow downstream blood flow and inhibit upstream blood flow; and a stator, which is configured to magnetically drive the magnetic piston with reciprocating motion, so as to pump blood downstream during downstream motion of the magnetic piston while the reciprocating one-way valve is closed. The pump further includes a spring, which is arranged to store energy during upstream motion of the magnetic piston and release the stored energy during the downstream motion of the magnetic piston. Control circuitry is configured to activate the tubular linear motor to provide pulsatile flow synchronized with cardiac cycles. Other configurations are also described.

An implantable LVAD is provided that includes a pump shaped so as to define a pump chamber. The pump includes a tubular linear motor, which includes a magnetic piston, which includes a reciprocating one-way valve configured to allow downstream blood flow and inhibit upstream blood flow; and a stator, which is configured to magnetically drive the magnetic piston with reciprocating motion, so as to pump blood downstream during downstream motion of the magnetic piston while the reciprocating one-way valve is closed. The pump further includes a spring, which is arranged to store energy during upstream motion of the magnetic piston and release the stored energy during the downstream motion of the magnetic piston. Control circuitry is configured to activate the tubular linear motor to provide pulsatile flow synchronized with cardiac cycles. Other configurations are also described.

A cardiac assist device with an expandable cup (4) having a transport state and an operational state, the expandable cup comprising a plurality of inflow apertures (5), and an outflow nozzle (6), and an inflatable balloon (8) positioned inside the expandable cup (4). A catheter assembly (3) is connected to the inflatable balloon (8) during operation, and a control unit (2) is connected to the catheter assembly (3). The control unit (2) is arranged to operate the inflatable balloon (8) with a frequency of more than 100 beats per minute.

A magnetic driver generates a magnetic field that rotates about an axis and induces nutation in a disc with an array of magnets (wobble plate). The magnetic driver can be a drive disc with an array of magnets and rotated by a drive motor, or can be electromagnetic coils sequentially energized, to provide the rotating magnetic field. The wobble plate nutates about the axis of the rotating magnetic field but is constrained from rotating about the axis. The wobble plate can be enclosed in a pump housing where nutation of the wobble plate causes pumping of a fluid to occur, such as in an implanted Left Ventricular Assist Device (LVAD) or a Total Artificial Heart (TAH). Driven in reverse, an input pumping fluid may induce nutation of the wobble plate which in turn induces rotary motion of a drive disc that drives a generator or a motor/generator.

A magnetic driver generates a magnetic field that rotates about an axis and induces nutation in a disc with an array of magnets (wobble plate). The magnetic driver can be a drive disc with an array of magnets and rotated by a drive motor, or can be electromagnetic coils sequentially energized, to provide the rotating magnetic field. The wobble plate nutates about the axis of the rotating magnetic field but is constrained from rotating about the axis. The wobble plate can be enclosed in a pump housing where nutation of the wobble plate causes pumping of a fluid to occur, such as in an implanted Left Ventricular Assist Device (LVAD) or a Total Artificial Heart (TAH). Driven in reverse, an input pumping fluid may induce nutation of the wobble plate which in turn induces rotary motion of a drive disc that drives a generator or a motor/generator.

A method is provided that includes inserting an inflow cannula of a left ventricular assist device (LVAD) of a LVAD system into a left chamber of a heart of a patient transeptally via a right atrium and a superior vena cava (SVC). An outflow cannula of the LVAD is coupled to a left subclavian artery or a left axillary artery. Other embodiments are also described.