Abstract: Apparatus and method for delivering and deploying an intravascular device into the vessel including an outer and inner tube that are axially linked by a housing structure at the proximal end of the catheter, and a retractable sleeve structure having a middle tube and sleeve tip. The sleeve tip is sealed to the inner tube at the distal end, and continuously extends into the middle tube. At the proximal end of the sleeve structure, the middle tube is sealed to either a housing structure or slideable proximal ring, forming a sealed chamber between the inner tube and the sleeve structure. A radial space is formed between the sleeve tip and the inner tube optimized for intravascular device placement. During retraction of the sleeve structure, the fold of the sleeve tip peels away from the device, which expands to its deployed state while minimizing axial forces and friction.

Abstract: Apparatus and methods are described including an impeller (50) that includes a proximal bushing (64) and a distal bushing (58). Two or more helical elongate elements (52) extend from the proximal bushing (64) to the distal bushing (58), and an axial structure (54) is disposed inside of the two or more helical elongate elements (52), and along an axis around which the helical elongate elements (52) wind. The impeller (50) includes an impeller-overexpansion-prevention element (72). The impeller-overexpansion-prevention element is a single integrated structure that includes a ring (73) disposed around the axial structure (54), and a plurality of elongate elements (67) each of the elongate elements (67) extending from the ring to a respective helical elongate element (52) and being coupled to the respective helical elongate element (52) so as to prevent radial expansion of the impeller (50). Other applications are also described.

Abstract: Apparatus and methods are described including a left-ventricular assist device that includes an impeller configured to be placed inside a subject's left ventricle and to pump blood from the 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 aorta and a distal portion of the tube is disposed within the left ventricle. The distal portion of the tube extends to the 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. Other applications are also described.

Abstract: Apparatus and methods are described including a ventricular assist device configured to assist ventricular functioning of a subject. The ventricular assist device includes an impeller and a frame disposed around the impeller. An axial shaft extends from a proximal end of the frame to a distal end of the frame, the impeller being coupled to the axial shaft. The axial shaft includes a proximal portion and a distal portion, which are coupled to each other via a joint. The proximal portion and the distal portion of the axial shaft are configured to flex with respect to each other via the joint. Other applications are also described.

Abstract: Apparatus and methods are described including a ventricular assist device that includes a blood pump configured to be placed inside a left ventricle of a subject and to pump blood from the subject's left ventricle to an aorta of the subject. A blood pressure sensor measures aortic pressure of the subject. A computer processor varies a flow rate that is that is generated by the blood pump, and determines a relationship between arterial pulsatility of the subject and the flow rate that is generated by the blood pump, based upon aortic pressure that is measured by the blood pressure sensor as the flow rate that is generated by the blood pump is varied. The computer processor estimates native cardiac output of the subject at least partially based upon the relationship. 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. A driving magnet is coupled to a motor and is rotated by the motor. A driven magnet is magnetically coupled to the driving magnet and is rotated by the driving magnet. A drive cable extends from the driven magnet and imparts rotational motion from the driven magnet to the impeller. A set of sensors is configured to detect a magnetic phase difference between the driven magnet and the driving magnet. A computer processor receives the detected magnetic phase difference and determines a physiological parameter of the subject, at least partially in response thereto. 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 of the structure, the first and second bushings being connected to one another by at least one elongate element. The elongate element is caused to radially expand and form at least one helical elongate element, at least partially by axially compressing the structure. The helical elongate element is coated with a coupling agent configured to enhance bonding between the helical elongate element and an elastomeric layer. The coated helical elongate element is coated with the elastomeric layer. Subsequently, an elastomeric film is coupled to the helical elongate element, such that the helical elongate element with the elastomeric film coupled thereto defines a blade of the impeller. Other applications are also described.

Abstract: Apparatus and method for delivering and deploying an intravascular device into the vessel including an outer and inner tube that are axially linked by a housing structure at the proximal end of the catheter, and a retractable sleeve structure having a middle tube and sleeve tip. The sleeve tip is sealed to the inner tube at the distal end, and continuously extends into the middle tube. At the proximal end of the sleeve structure, the middle tube is sealed to either a housing structure or slideable proximal ring, forming a sealed chamber between the inner tube and the sleeve structure. A radial space is formed between the sleeve tip and the inner tube optimized for intravascular device placement. During retraction of the sleeve structure, the fold of the sleeve tip peels away from the device, which expands to its deployed state while minimizing axial forces and friction.

Abstract: Apparatus and method for delivering and deploying an intravascular device into the vessel including an outer and inner tube that are axially linked by a housing structure at the proximal end of the catheter, and a retractable sleeve structure having a middle tube and sleeve tip. The sleeve tip is sealed to the inner tube at the distal end, and continuously extends into the middle tube. At the proximal end of the sleeve structure, the middle tube is sealed to either a housing structure or slideable proximal ring, forming a sealed chamber between the inner tube and the sleeve structure. A radial space is formed between the sleeve tip and the inner tube optimized for intravascular device placement. During retraction of the sleeve structure, the fold of the sleeve tip peels away from the device, which expands to its deployed state while minimizing axial forces and friction.

Abstract: Apparatus and method for delivering and deploying an intravascular device into the vessel including an outer and inner tube that are axially linked by a housing structure at the proximal end of the catheter, and a retractable sleeve structure having a middle tube and sleeve tip. The sleeve tip is sealed to the inner tube at the distal end, and continuously extends into the middle tube. At the proximal end of the sleeve structure, the middle tube is sealed to either a housing structure or slideable proximal ring, forming a sealed chamber between the inner tube and the sleeve structure. A radial space is formed between the sleeve tip and the inner tube optimized for intravascular device placement. During retraction of the sleeve structure, the fold of the sleeve tip peels away from the device, which expands to its deployed state while minimizing axial forces and friction.

Abstract: Apparatus and method for delivering and deploying an intravascular device into the vessel including an outer and inner tube that are axially linked by a housing structure at the proximal end of the catheter, and a retractable sleeve structure having a middle tube and sleeve tip. The sleeve tip is sealed to the inner tube at the distal end, and continuously extends into the middle tube. At the proximal end of the sleeve structure, the middle tube is sealed to either a housing structure or slideable proximal ring, forming a sealed chamber between the inner tube and the sleeve structure. A radial space is formed between the sleeve tip and the inner tube optimized for intravascular device placement. During retraction of the sleeve structure, the fold of the sleeve tip peels away from the device, which expands to its deployed state while minimizing axial forces and friction.

Abstract: Apparatus and method for delivering and deploying an intravascular device into the vessel including an outer and inner tube that are axially linked by a housing structure at the proximal end of the catheter, and a retractable sleeve structure having a middle tube and sleeve tip. The sleeve tip is sealed to the inner tube at the distal end, and continuously extends into the middle tube. At the proximal end of the sleeve structure, the middle tube is sealed to either a housing structure or slideable proximal ring, forming a sealed chamber between the inner tube and the sleeve structure. A radial space is formed between the sleeve tip and the inner tube optimized for intravascular device placement. During retraction of the sleeve structure, the fold of the sleeve tip peels away from the device, which expands to its deployed state while minimizing axial forces and friction.

Abstract: Apparatus and method for delivering and deploying an intravascular device into the vessel including an outer and inner tube that are axially linked by a housing structure at the proximal end of the catheter, and a retractable sleeve structure having a middle tube and sleeve tip. The sleeve tip is sealed to the inner tube at the distal end, and continuously extends into the middle tube. At the proximal end of the sleeve structure, the middle tube is sealed to either a housing structure or slideable proximal ring, forming a sealed chamber between the inner tube and the sleeve structure. A radial space is formed between the sleeve tip and the inner tube optimized for intravascular device placement. During retraction of the sleeve structure, the fold of the sleeve tip peels away from the device, which expands to its deployed state while minimizing axial forces and friction.

Abstract: Apparatus and method for delivering and deploying an intravascular device into the vessel including an outer and inner tube that are axially linked by a housing structure at the proximal end of the catheter, and a retractable sleeve structure having a middle tube and sleeve tip. The sleeve tip is sealed to the inner tube at the distal end, and continuously extends into the middle tube. At the proximal end of the sleeve structure, the middle tube is sealed to either a housing structure or slideable proximal ring, forming a sealed chamber between the inner tube and the sleeve structure. A radial space is formed between the sleeve tip and the inner tube optimized for intravascular device placement. During retraction of the sleeve structure, the fold of the sleeve tip peels away from the device, which expands to its deployed state while minimizing axial forces and friction.