Abstract: Apparatus and methods are described including a blood pump configured to be placed inside a body of subject. The blood pump includes an impeller, a frame disposed around the impeller, and a distal-tip portion disposed distally with respect to the frame. A duckbill valve is disposed entirely within a distal most 10 mm of the distal-tip portion. The duckbill valve defines a wide inlet and a narrow tip that defines a slit therethrough. The duckbill valve is proximally facing, such that the wide inlet faces a distal end of the distal-tip portion and such that the narrow tip faces away from the distal end of distal-tip portion. Other applications are also described.

Abstract: An assembly for driving movement of an elongate surgical tool, comprising: a plurality of adjacent pairs of driving wheels, each pair of driving wheels having a space therebetween such that spaces of the plurality of pairs of driving wheels are axially aligned to form a channel for the elongate surgical tool to extend through; wherein at least one pair of driving wheels out of the plurality of pairs is arranged to lie on a plane different than a plane on which at least one other pair of driving wheels lies.

Abstract: Apparatus and methods are described including a blood pump that includes an impeller configured to be delivered through vasculature of a subject while the impeller is in a radially-constrained configuration. The impeller is configured to self-expand to a non-radially-constrained configuration, and to pump blood while in the non-radially-constrained configuration. A ratio between (a) a diameter of the impeller when the impeller is in its non-radially-constrained configuration at a location at which the diameter of the impeller is at its maximum and (b) a diameter of the impeller when the impeller is in its radially-constrained configuration is greater than 7:2. Other applications are also described.

Abstract: Apparatus and methods are described, including a left-ventricular assist device that includes an impeller, and a frame disposed around the impeller, the frame having a length of more than 25 mm when disposed in a non-radially constrained configuration. A rigid axial shaft extends from a proximal end of the frame to a distal end of the frame. A motor is disposed outside a body of a subject, and drives the impeller to pump blood within the subject's body, by rotating. A drive cable extends from outside the subject's body to the axial shaft. The drive cable imparts rotational motion from the motor to the impeller by rotating. The drive cable is a flexible cable comprising a plurality of coiled wires. Other applications are also described.

Abstract: Apparatus and methods are described including a left ventricular assist device. The left ventricular assist device includes an impeller configured to be placed inside a subject's left ventricle, and to pump blood from the subject's left ventricle to the subject's aorta, by rotating. A frame is disposed around the impeller. A tube traverses the subject's aortic valve, such that a proximal portion of the tube is disposed within the subject's aorta and a distal portion of the tube is disposed within the subject's left ventricle. The distal portion of the tube defines one or more blood inlet openings that are configured to allow blood to flow from the subject's left ventricle into the tube. A braided element is configured to prevent inner structures of the left ventricle from passing into the one or more blood inlet openings. Other applications are also described.

Abstract: Apparatus and methods are described including a blood pump configured to be placed inside a body of subject, the blood pump including an impeller configured to pump the subject's blood by rotating, and an axial shaft upon which the impeller is disposed. Proximal and distal radial bearings are configured to stabilize the axial shaft radially during rotation of the impeller. An atraumatic distal-tip portion is disposed distally with respect to the impeller, the atraumatic distal-tip portion including an inflatable portion. A purging fluid is pumped toward the distal-tip portion, such as to (a) purge the distal bearing, and (b) inflate the inflatable portion of the distal-tip portion. Other applications are also described.

Abstract: Apparatus and methods are described including a left ventricular assist device. The left ventricular assist device includes an impeller configured to be placed inside a subject's left ventricle, and to pump blood from the subject's left ventricle to the subject's aorta, by rotating. A frame is disposed around the impeller. A tube traverses the subject's aortic valve, such that a proximal portion of the tube is disposed within the subject's aorta and a distal portion of the tube is disposed within the subject's left ventricle. The distal portion of the tube defines one or more blood inlet openings that are configured to allow blood to flow from the subject's left ventricle into the tube. A mesh is configured to prevent inner structures of the left ventricle from passing into the one or more blood inlet openings. Other applications are also described.

Abstract: Apparatus and methods are described including a ventricular assist device that includes an impeller configured to be placed inside a left ventricle of a subject, and a frame configured to be disposed around the impeller. The frame is shaped such that, in a non-radially constrained configuration of the frame, the frame defines a cylindrical central portion, and a distal conical portion that is disposed distally with respect to the cylindrical central portion and that widens from a distal end of the frame to a distal end of the cylindrical central portion. The frame defines struts that define openings therebetween, and all openings that are defined at least partially within the distal conical portion of the frame extend into the cylindrical central portion of the frame. Other applications are also described.

Abstract: An assembly for driving movement of an elongate surgical tool, comprising: a plurality of adjacent pairs of driving wheels, each pair of driving wheels having a space therebetween such that spaces of the plurality of pairs of driving wheels are axially aligned to form a channel for the elongate surgical tool to extend through; wherein at least one pair of driving wheels out of the plurality of pairs is arranged to lie on a plane different than a plane on which at least one other pair of driving wheels lies.

Abstract: Apparatus and methods are described including a ventricular assist device that includes an impeller configured to be placed inside a subject's left ventricle. A frame is disposed around the impeller, the frame defining generally-cylindrical central portion, and a proximal conical portion that widens from a proximal end of the frame to a proximal end of the generally-cylindrical central portion. A motor drives the impeller to pump blood from the left ventricle to the subject's aorta, by rotation of the impeller. The impeller is configured to be disposed at least partially within the proximal conical portion of the frame during at least some of a time during which the impeller rotates. Other applications are also described.

Abstract: Apparatus and methods are described including a blood pump that includes an axial shaft, an impeller disposed on the axial shaft, a frame disposed around the impeller, and a motor disposed outside a subject's body, and configured to drive the impeller to pump blood from a distal end of the impeller to a proximal end of the impeller. A drive cable extends from outside the subject's body to the axial shaft, and is configured to impart rotational motion from the motor to the impeller by rotating. The drive cable is held in a preloaded state with respect to the frame, such that initiation of pumping of blood by rotation of the impeller does not cause the drive cable to axially elongate. Other applications are also described.

Abstract: Apparatus and methods are described including a blood pump that includes an impeller, and a motor configured to drive the impeller to pump blood by rotating the impeller. The impeller is configured to undergo axial motion, in response to changes in a pressure against which the impeller is pumping. A sensor detects the axial motion of the impeller, and generates a sensor signal in response thereto. A computer processor receives the sensor signal and generates an output in response thereto. Other applications are also described.

Abstract: A blood pump is described that includes an impeller having proximal and distal bushings, at least one helical elongate element, a spring that is disposed inside of the helical elongate element and along an axis around which the helical elongate element winds, and a film of material supported between the helical elongate element and the spring. A frame is disposed around the impeller. A flexible elongate element extends radially from the spring to the helical elongate element, and maintains the helical elongate element within a given distance from the spring, to thereby maintain a gap between an outer edge of a blade of the impeller and an inner surface of the frame, during rotation of the impeller. Other applications are also described.

Abstract: Apparatus comprising and methods are described including a blood pump that includes an axial shaft, and an impeller disposed on the axial shaft. The impeller is configured to pump blood of the subject by rotating. The impeller and the axial shaft are configured to undergo axial back-and-forth motion during operation of the impeller. A distal tip element is disposed at a distal end of the blood pump. The distal tip element defines an axial-shaft-receiving tube, configured to receive at least a portion of the axial shaft during forward motion of the axial shaft. The distal tip element additionally defines an atraumatic distal tip portion disposed distally of the axial-shaft-receiving tube. Other applications are also described.

Abstract: Apparatus and methods are described including manufacturing an impeller by forming a structure having first and second bushings at proximal and distal ends that are connected to one another by at least one elongate element. The elongate element is made to radially expand and form a helical elongate element. An elastomeric material is coupled to the helical elongate element, such that the helical elongate element with the elastomeric material coupled thereto defines a blade of the impeller. The coupling is performed such that a layer of the material disposed around a radially outer edge of the helical elongate element forms the effective edge of the impeller blade. A step is performed to enhance bonding of the elastomeric material to the helical elongate element in a manner that does not cause a protrusion from the effective edge of the impeller blade. Other applications are also described.

Abstract: An implant system is provided, which includes an implant, including an implant body and an electrode disposed on the implant body; and a hollow needle, which is configured to be percutaneously advanceable into tissue of a subject. The hollow needle is shaped so as to define a lumen dimensioned to house the implant; at a distal end of the hollow needle, a distal end opening configured to facilitate passage of the implant therethrough from the lumen; and a lateral wall shaped so as to define a window therethrough to the lumen. Other embodiments are also described.

Abstract: Apparatus and methods are described including a blood pump that includes an impeller configured to pump blood through a subject's body, and a frame disposed around the impeller. In a radially-non-constrained configuration of the frame, the frame defines a proximal conical portion and a cylindrical portion disposed distally to the proximal conical portion. During operation of the blood pump, the impeller moves with respect to the frame, and a range of movement of the impeller is such that at least a first portion of the impeller is disposed within the proximal conical portion of the frame during at least some of the operation of the blood pump, and at least a second portion of the impeller is disposed within the cylindrical portion of the frame during at least some of the operation of the blood pump. Other applications are also described.

Abstract: Apparatus and methods are described including coupling a rigid tube to a drive cable that comprises a plurality of coiled wires, by placing ends of the drive cable and the rigid tube at a given location within a butt-welding overtube. The ends of the drive cable and the rigid tube are visible when they are disposed at the given location within the butt-welding overtube, via a window defined by the butt-welding overtube. The placement of the drive cable within the butt-welding overtube is such that a helical groove within a portion of the butt-welding overtube is disposed over the drive cable. Welding rings are formed around the butt-welding overtube. Other applications are also described.

Abstract: Apparatus and methods are described including a blood pump that includes an impeller configured to pump blood through a subject's body, and a frame disposed around the impeller. The frame defines struts having a structure that is such that, as the frame transitions from a proximal end of the frame toward a center of the frame, the struts pass through junctions, at which the two struts branch from a single strut, in a Y-shape. The structure of the struts of the frame is configured such that, in response to a distal end of a delivery catheter and the frame being moved into overlapping positions with respect to each other, the frame assumes a radially-constrained configuration by becoming axially elongated, and the frame causes the impeller to assume a radially-constrained configuration by becoming axially elongated. Other applications are also described.

Abstract: An implant that includes an electrode is advanced to a nerve of a subject using a tube. The tube and the implant are arranged at a nonzero angle with respect to a skin surface of the subject, and the implant is passed distally from an opening of the tube, in a vicinity of a portion of the nerve. A longitudinal axis of the implant is realigned to become generally parallel with the skin surface, by proximally withdrawing the tube from the subject. Other embodiments are also described.