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: 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 tube configured to traverse a subject's aortic valve. A frame is disposed within a portion of the tube, and a plurality of winged projections are coupled to the frame. An impeller is disposed inside the tube, the impeller including proximal and distal bushings, a helical elongate element, and a spring disposed inside of the helical elongate element, the spring defining a lumen therethrough. A film of material is supported between the helical elongate element and the spring. A rigid shaft extends from the proximal bushing to the distal bushing via the lumen defined by the spring. The impeller is rotated, such as to pump blood from the subject's left ventricle to the subject's aorta. 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: 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 at least one motor configured to be disposed outside a body of a subject, a catheter, a proximal impeller disposed on the catheter and configured to pump blood by rotating, and a distal impeller disposed on the catheter. The distal impeller is configured to pump blood by rotating and is disposed on the catheter distally to the proximal impeller such that longitudinal centers of the proximal and distal impellers are separated from each other by at least 3 cm. Other applications are also described.

Abstract: Apparatus and methods are described for manufacturing a housing for an impeller of a blood pump. A frame is treated in order to enhance bonding between an inner surface of the frame and an inner lining. Subsequently, the inner lining is coupled to the inner surface of the frame along at least a portion of a central cylindrical portion of the frame. Subsequent to coupling the inner lining to the inner surface of the frame along at least a portion of the central cylindrical portion of the frame, a portion of an elongate tube is placed around at least a portion of the frame. While heating the inner lining, the frame, and the portion of the elongate tube, pressure is applied such as to cause the portion of the elongate tube to become coupled to the frame. Other applications are also described.

Abstract: Apparatus and methods are described including a left-ventricular assist device that includes an impeller (50) and a frame (34) disposed around the impeller (50). The frame (34) includes strut junctions (33) at a proximal end of the frame, the strut junctions (33) being configured to be maintained in open states, during assembly of the left ventricular assist device, to facilitate insertion of the impeller (50) into the frame (34). A securing element (117) holds the struts junctions in closed states, subsequent to the insertion of the impeller (50) into the frame (34). A pump-outlet tube (24) extends to a distal end of the frame (34) and defines one or more lateral blood inlet openings (108) that are configured to allow blood to flow from the subject's left ventricle into the pump-outlet tube (24). Other applications are also described.

Abstract: Apparatus and methods are described including a left-ventricular assist device including an impeller and a frame disposed around the impeller. A pump-outlet tube traverses the subject's aortic valve with a distal portion of the pump-outlet tube disposed within the subject's left ventricle. The distal portion of the pump-outlet tube extends to a distal end of the frame and defines more than 10 blood-inlet openings that are sized such as (a) to allow blood to flow from the subject's left ventricle into the tube and (b) to block structures from the subject's left ventricle from entering into the frame. The porosity of the distal portion of the pump-outlet tube is lower within a proximal region of the distal portion of the pump-outlet tube than within a distal region of the distal portion of the pump-outlet tube that is distal to the proximal region. Other applications are also described.

Abstract: Apparatus and methods are described for manufacturing a housing for an impeller of a blood pump. A mandrel is placed inside an inner lining, with a central cylindrical portion of a frame disposed around the inner lining, the mandrel being shorter than a length of the inner lining. A portion of an elongate tube is placed around at least a portion of the frame. The inner lining, the frame and the portion of the elongate tube are heated, via the mandrel, and, while heating the inner lining, the frame, and the portion of the elongate tube, pressure is applied from outside the portion of the elongate tube, such as to cause the portion of the elongate tube to become coupled to the frame. Other applications are also described.

Abstract: Apparatus and methods are described including a ventricular assist device that includes an impeller disposed within a frame and configured to pump blood through a pump-outlet tube and out of one of more blood outlet openings. The frame includes an inner lining. A protective braid is disposed over a distal portion of the frame and configured to block structures from the subject's left ventricle from entering into the frame. A proximal end of the protective braid is embedded between the pump-outlet tube and the inner lining, such that, during crimping of the frame, the braid becomes crimped with the pump-outlet tube and the inner lining, thereby preventing the braid from moving with respect to pump-outlet tube or the inner lining. 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: Apparatus and methods are described, including a blood pump that includes a catheter, a proximal impeller disposed on the catheter inside a proximal impeller housing, and which is configured to pump blood by rotating inside the proximal impeller housing. A distal impeller is disposed on the catheter inside a distal impeller housing, distally to the proximal impeller, and the distal impeller is configured to pump blood by rotating inside the distal impeller housing. A tubular element is disposed between the proximal impeller housing and the distal impeller housing, the tubular element being configured to have a tubular configuration during rotation of the proximal and distal impellers. 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. 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.