A mechanical circulatory assist device is provided including a stent, a coiled wire wound around the stent, and a reciprocating valve including a housing, one or more leaflets coupled to the housing, and one or more permanent magnets coupled to the housing. The magnets are arranged to interact with a magnetic field generated by the coiled wire when current flows therethrough, so as to axially move the reciprocating valve with respect to the stent when the reciprocating valve is disposed within the stent. Upstream axial motion of the reciprocating valve causes the leaflets to be in an open state in which they allow blood flow through the reciprocating valve. Downstream axial motion of the reciprocating valve causes the leaflets to be in a closed state in which they inhibit blood flow through the reciprocating valve. Other embodiments are also described.

A mechanical circulatory assist device is provided including a stent, a coiled wire wound around the stent, and a reciprocating valve including a housing, one or more leaflets coupled to the housing, and one or more permanent magnets coupled to the housing. The magnets are arranged to interact with a magnetic field generated by the coiled wire when current flows therethrough, so as to axially move the reciprocating valve with respect to the stent when the reciprocating valve is disposed within the stent. Upstream axial motion of the reciprocating valve causes the leaflets to be in an open state in which they allow blood flow through the reciprocating valve. Downstream axial motion of the reciprocating valve causes the leaflets to be in a closed state in which they inhibit blood flow through the reciprocating valve. Other embodiments are also described.

Apparatus and methods are described including a catheter, and first and second impellers configured to be inserted into a subject's body via the catheter, the first and second impellers being disposed in series with each other. A first impeller cage is disposed around the first impeller, and a second impeller cage is disposed around the second impeller. A sleeve extends longitudinally along more than 50 percent of a distance between the first and second impellers. Other applications are also described.

Apparatus and methods are described including a catheter, and first and second impellers configured to be inserted into a subject's body via the catheter, the first and second impellers being disposed in series with each other. A first impeller cage is disposed around the first impeller, and a second impeller cage is disposed around the second impeller. A sleeve extends longitudinally along more than 50 percent of a distance between the first and second impellers. Other applications are also described.

Methods and devices for supporting circulation. The methods may include positioning a blood pump in the arterial vasculature or the venous vasculature. The methods may include positioning a pump portion of the blood pump in a descending aorta, an inferior vena cava, a renal artery, and/or a renal vein. The methods include delivering a pump portion of a blood pump to a target location and rotating one or more impellers to move blood through the pump portion.

A mechanical circulatory assist device is provided including a stent, a coiled wire wound around the stent, and a reciprocating valve including a housing, one or more leaflets coupled to the housing, and one or more permanent magnets coupled to the housing. The magnets are arranged to interact with a magnetic field generated by the coiled wire when current flows therethrough, so as to axially move the reciprocating valve with respect to the stent when the reciprocating valve is disposed within the stent. Upstream axial motion of the reciprocating valve causes the leaflets to be in an open state in which they allow blood flow through the reciprocating valve. Downstream axial motion of the reciprocating valve causes the leaflets to be in a closed state in which they inhibit blood flow through the reciprocating valve. Other embodiments are also described.

A mechanical circulatory assist device is provided including a stent, a coiled wire wound around the stent, and a reciprocating valve including a housing, one or more leaflets coupled to the housing, and one or more permanent magnets coupled to the housing. The magnets are arranged to interact with a magnetic field generated by the coiled wire when current flows therethrough, so as to axially move the reciprocating valve with respect to the stent when the reciprocating valve is disposed within the stent. Upstream axial motion of the reciprocating valve causes the leaflets to be in an open state in which they allow blood flow through the reciprocating valve. Downstream axial motion of the reciprocating valve causes the leaflets to be in a closed state in which they inhibit blood flow through the reciprocating valve. Other embodiments are also described.

The devices and methods described herein include an implantable body lumen fluid flow modulator including an upstream flow accelerator separated by a gap from a downstream flow decelerator. The gap is a pathway to entrain additional fluid from a branch lumen(s) into the fluid stream flowing from the upstream flow accelerator to the downstream flow decelerator.

A catheter pump having a rotor shaft rotatably arranged in the inner catheter for driving an expandable conveyor element provided at the pump head. The conveyor element is rotatably mounted between a. distal hearing point and a proximal bearing point, wherein the outer catheter has a sleeve section on the distal end thereof surrounding the proximal bearing point, and wherein the proximal bearing point can be moved in the axial direction relative to the sleeve section in order to expand the conveyor element, wherein the proximal bearing point comprises a bearing receiver having a rotational bearing point for a rotary head rotationally fixed to the distal end of the rotor shaft, and a force application point at an axial distance to same for a force application section provided at the distal end of the inner catheter for axially moving the proximal bearing points relative to the sleeve section.

A catheter pump having a rotor shaft rotatably arranged in the inner catheter for driving an expandable conveyor element provided at the pump head. The conveyor element is rotatably mounted between a. distal hearing point and a proximal bearing point, wherein the outer catheter has a sleeve section on the distal end thereof surrounding the proximal bearing point, and wherein the proximal bearing point can be moved in the axial direction relative to the sleeve section in order to expand the conveyor element, wherein the proximal bearing point comprises a bearing receiver having a rotational bearing point for a rotary head rotationally fixed to the distal end of the rotor shaft, and a force application point at an axial distance to same for a force application section provided at the distal end of the inner catheter for axially moving the proximal bearing points relative to the sleeve section.