Abstract: A system includes a core and a catheter for use with (A) a first atrial arm and a first ventricular arm articulatable with respect to each other at a first articulation site to clamp one leaflet of a patient's native heart valve, and (B) a second atrial arm and a second ventricular arm articulatable with respect to each other at a second articulation site to clamp another native leaflet of the native valve. The core tapers in a distal direction toward its smallest perimeter, defining a minimum nonzero angle of the atrial arms with respect to a central longitudinal axis of the core. The catheter advances the core and the arms toward the native valve. The catheter and the core have an advancement configuration in which the smallest perimeter of the core is adjacent to the first and second articulation sites. Other embodiments are also described.

Abstract: A transluminal sheath is advanced transseptally into a left atrium of the subject. A distal end of a surrounding-sheath, having an anchor disposed therein, is advanced via a distal end of the transluminal sheath, into a left ventricle of the subject via a commissure of the mitral valve. While the distal end of the surrounding-sheath is in the left ventricle, the surrounding-sheath is pulled proximally with respect to the anchor to expose the anchor. While the distal end of the surrounding-sheath is in the left ventricle, mitral valve tissue that is within the left ventricle is encircled by helically wrapping the anchor around the mitral valve tissue. Subsequently, the surrounding-sheath is extracted from the heart. Other embodiments are also described.

Abstract: Apparatus is described for administering a substance to a subject. A vial contains the substance and a stopper is disposed within the vial and is slidably coupled to the vial. A first threaded element is (a) rotatable with respect to the vial and (b) substantially immobile proximally with respect to the vial during rotation of the first threaded element. A second threaded element is threadedly coupled to the first threaded element. At least a distal end of the second threaded element is substantially non-rotatable with respect to the vial, and the distal end of the second threaded element defines a coupling portion that couples the second threaded element to the stopper. The first threaded element, by rotating, linearly advances the stopper and at least the distal end of the second threaded element toward a distal end of the vial. Other embodiments are also described.

Abstract: A method for treating an intervertebral disc of a subject is provided, the method including delivering a growth factor to a nucleus pulposus of the intervertebral disc. At least one intra-pulposus exposed electrode surface is implanted in the nucleus pulposus. At least one extra-pulposus exposed electrode surface is implanted in a body of the subject outside the nucleus pulposus. The growth factor is supported by activating control circuitry to drive the intra-pulposus and the extra-pulposus exposed electrode surfaces to electroosmotically drive nutrient-containing fluid into the nucleus pulposus. Other embodiments are also described.

Abstract: Apparatus is provided for treating heart failure, the apparatus including one or more propeller blades and a controller, which is configured to rotate the one or more propeller blades to produce continuous non-pulsatile blood flow not synchronized with a cardiac cycle of a subject. An intra-atrial anchor includes a stent surrounding the one or more propeller blades. The intra-atrial anchor is coupled to the one or more propeller blades and configured to be anchored in a left atrium of the subject so as to position the one or more propeller blades in the left atrium oriented such that the one or more propeller blades, when rotated by the controller, draw blood from the left atrium and expel the blood in the left atrium toward a mitral valve, thereby increasing atrial pressure above the mitral valve. Other embodiments are also described.

Abstract: Apparatus is provided for treating an intervertebral disc of a subject, the apparatus including: at least one intra-pulposus exposed electrode surface, which is configured to be implanted in a nucleus pulposus of the intervertebral disc; and one or more extra-pulposus exposed electrode surfaces, which are configured to be implanted outside the nucleus pulposus, in electrical communication with the intervertebral disc. Control circuitry is electrically coupled to the at least one intra-pulposus exposed electrode surface and one or more extra-pulposus exposed electrode surfaces. The control circuitry is configured to drive fluid and introduce nutritional substances into the intervertebral disc, by applying a voltage between the at least one intra-pulposus exposed electrode surface and the one or more extra-pulposus exposed electrode surfaces. Other embodiments are also described.

Abstract: Apparatus is provided that includes a two-dimensional arrangement (70) of extracranial electrodes (30), configured to be placed outside and in electrical contact with a skull of a subject identified as at risk of or suffering from a disease; and a cerebrospinal fluid (CSF) electrode (32), configured to be implanted in a ventricular system of a brain of the subject. Control circuitry is configured to drive the extracranial and the CSF electrodes (30, 32) to clear a substance from brain parenchyma of the subject into at least one region of the brain selected from the group consisting of: a subarachnoid space of the brain and dural sinuses of the brain. Other embodiments 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.

Abstract: Apparatus and methods are described including an implantable device having first and second longitudinal ends, the device having a length of less than 80 mm when the device is unconstrained. The device includes struts arranged such that, when the device is unconstrained, along a continuous portion of the device having a length that is at least 5 mm, a maximum inter-strut distance defined by any set of two adjacent struts is more than 1.5 times as great as a maximum inter-strut distance defined by any set of two adjacent struts within longitudinal portions of the device within 3 mm of the longitudinal ends of the device. Other applications are also described.

Abstract: A method is provided including disposing midplane treatment electrodes over a superior sagittal sinus, outside and in electrical contact with a skull of a head of a subject identified as at risk of or suffering from Alzheimer's disease. Lateral treatment electrodes are disposed between 1 and 12 cm of a sagittal midplane of the skull. The subject is treated by clearing amyloid beta, by activating control circuitry to apply one or more treatment currents between (a) one or more of the midplane treatment electrodes and (b) one or more of the lateral treatment electrodes; and configure the midplane treatment electrodes as cathodes, and the lateral treatment electrodes as anodes. Other embodiments are also described.

Abstract: A transluminal sheath is advanced into a femoral vein of a subject, through an inferior vena cava of the subject, into a right atrium of a heart of the subject, and transseptally into a left atrium of the heart. A surrounding-sheath is advanced out of a distal end of the transluminal sheath, into the left atrium, and toward a commissure of a mitral valve of the heart. A commissural helix is implanted at the commissure by advancing the commissural helix out of the surrounding-sheath and through the commissure into a left ventricle of the heart, such that the commissural helix wraps around at least some chordae tendineae at the commissure and facilitates sealing of the commissure. Subsequently to the implantation of the commissural helix, the surrounding-sheath is extracted from the heart. Other embodiments are also described.

Abstract: A method is provided including disposing central electrodes outside and in electrical contact with a skull of a head of a subject identified as at risk of or suffering from Alzheimer's disease, within one cm of a sagittal midplane of the skull; and disposing peripheral electrodes outside and in electrical contact with the skull, superior to an orbitomeatal plane of the skull and inferior to a first plane midway between the orbitomeatal plane and a cranial vertex of the skull, the first plane parallel to the orbitomeatal plane. The subject is treated by clearing amyloid beta, tau protein, and/or metal ions from brain parenchyma to a subarachnoid space, by activating control circuitry to apply respective currents between one or more of the central electrodes and two or more of the peripheral electrodes, and configure the central electrodes as cathodes and the peripheral electrodes as anodes. Other embodiments are also described.

Abstract: An implant includes a housing that houses circuitry that is electrically coupled to one or more electrodes. The implant includes an antenna that is electrically coupled to the circuitry. The antenna has a pre-treatment state in which the antenna is not shaped to receive wireless power for treating a subject, and a treatment state in which the antenna is shaped to receive wireless power and to anchor the implant with respect to a nerve of the subject. Other embodiments are also described.

Abstract: A method for repairing a heart includes identifying a heart of a patient as having a reduced ejection fraction. In response to the identifying, wall stress of a ventricle of the heart is reduced by implanting apparatus that facilitates cyclical moving of fluid that is not blood of the patient into and out of the ventricle of the heart. During ventricular diastole, a volume of the fluid is moved into the ventricle in a manner that produces a corresponding decrease in a total volume of blood that fills the ventricle during diastole. During ventricular systole, the volume of the fluid is moved out of the ventricle in a manner that produces a corresponding decrease in a total volume of the ventricle during isovolumetric contraction of the ventricle. Other embodiments are also described.

Abstract: An electrical amyloid beta-clearance system for treating a subject identified as at risk of or suffering from Alzheimer's disease is provided, the system including midplane treatment electrodes, adapted to be disposed over a superior sagittal sinus, outside and in electrical contact with a skull of a head of the subject; lateral treatment electrodes, adapted to be disposed between 1 and 12 cm of a sagittal midplane of the skull; and control circuitry, configured to clear amyloid beta from a subarachnoid space to the superior sagittal sinus, by applying one or more treatment currents between (a) one or more of the midplane treatment electrodes and (b) one or more of the lateral treatment electrodes. Other embodiments are also described.

Abstract: A method includes advancing apparatus including a core toward a patient's heart valve. The core tapers in a distal direction toward the smallest perimeter of the core. The apparatus includes a first ventricular arm, which is articulatable with respect to a first atrial arm at a first articulation site, and a second ventricular arm, which is articulatable with respect to a second atrial arm at a second articulation site. The articulation sites are adjacent to the smallest perimeter. The tapering of the core defines a minimum nonzero angle of the atrial arms with respect to a central longitudinal axis of the core. The method also includes clamping the first and second leaflets between the respective atrial arms and the respective ventricular arms. Other embodiments are also described.

Abstract: Apparatus (20) for treating an intervertebral disc (30) of a subject is provided. The apparatus (20) includes at least three intra-pulposus exposed electrode surfaces (40), which are configured to be implanted within a nucleus pulposus (42) of the disc (30), at different respective locations; and one or more extra-pulposus exposed electrode surfaces (44), which are configured to be implanted outside the nucleus pulposus (42), in electrical communication with the disc (30). Control circuitry (50) is configured to (a) configure the intra-pulposus exposed electrode surfaces (40) to be cathodes, and the one or more extra-pulposus exposed electrode surfaces (44) to be one or more anodes, and (b) drive the intra-pulposus exposed electrode surfaces (40) and the one or more extra-pulposus exposed electrode surfaces (44) to electroosmotically drive fluid into the nucleus pulposus (40) to increase pressure in the disc (30).

Abstract: A method of treating diastolic heart failure includes implanting a cardiac implant in a heart of a subject diagnosed as suffering from diastolic heart failure. A superior portion of a flexible tether of the cardiac implant is anchored to one or more left-atrial sites of one or more walls of the left atrium. An inferior portion of the flexible tether is anchored to a site of a wall of a mid third of the left ventricle, of a wall of an apical third of the left ventricle, and/or of a papillary muscle of the left ventricle. As a result, the flexible tether reduces a volume of the left atrium during at least a portion of ventricular diastole of each cardiac cycle, thereby enhancing ventricular filling. Other embodiments are also described.

Abstract: A method of treating hyaline cartilage of a subject is provided, the method including implanting a first exposed electrode surface in osteochondral tissue of the subject, and implanting a second exposed electrode surface in a body of the subject. Regeneration of the hyaline cartilage is promoted by activating control circuitry to drive the first and the second exposed electrode surfaces to drive nutrients toward the first exposed electrode surface. Other embodiments are also described.

Abstract: Implantable first atrial and ventricular arms are articulatable at a first articulation site to clamp a first heart valve leaflet. A first implantable elongate transitioning member is (a) connected at a fixed connection point at a portion of the first ventricular arm farthest from the first articulation site, (b) has a portion that faces an opposite surface of the first ventricular arm, and (c) is controllable to move the first ventricular arm. Implantable second atrial and ventricular arms are articulatable at a second articulation site to clamp a second leaflet. A second implantable elongate transitioning member is (a) connected at a fixed connection point at a portion of the second ventricular arm farthest from the second articulation site, (b) has a portion that faces an opposite surface of the second ventricular arm, and (c) is controllable to move the second ventricular arm. Other embodiments are also described.