146 results about "Loop of Henle" patented technology

A prosthetic heart valve (10) (e.g., a prosthetic aortic valve) is designed to be somewhat circumferentially collapsible and then re-expandable. The collapsed condition may be used for less invasive delivery of the valve into a patient. When the valve reaches the implant site in the patient, it re-expands to normal operating size, and also to engage surrounding tissue of the patient. The valve includes a stent portion (200) and a ring portion (100) that is substantially concentric with the stent portion but downstream from the stent portion in the direction of blood flow through the implanted valve. When the valve is implanted, the stent portion engages the patient's tissue at or near the native valve annulus, while the ring portion engages tissue downstream from the native valve site (e.g., the aorta).

Methods and devices for use in tissue approximation and fixation are described herein. The present invention provides, in part, methods and devices for acquiring tissue folds in a circumferential configuration within a hollow body organ, e.g., a stomach, positioning the tissue folds for affixing within a fixation zone of the stomach, preferably to create a pouch or partition below the esophagus, and fastening the tissue folds such that a tissue ring, or stomas, forms excluding the pouch from the greater stomach cavity. The present invention further provides for a liner or bypass conduit which is affixed at a proximal end either to the tissue ring or through some other fastening mechanism. The distal end of the conduit is left either unanchored or anchored within the intestinal tract. This bypass conduit also includes a fluid bypass conduit which allows the stomach and a portion of the intestinal tract to communicate.

A mitral heart valve annuloplasty ring having a posterior bow that conforms to an abnormal posterior aspect of the mitral annulus. The ring may be generally oval having a major axis and a minor axis, wherein the posterior bow may be centered along the minor axis or offset in a posterior section. The ring may be substantially planar, or may include upward bows on either side of the posterior bow. The ring may include a ring body surrounded by a suture-permeable fabric sheath, and the ring body may be formed of a plurality of concentric ring elements. The ring is semi-rigid and the posterior bow is stiff enough to withstand deformation once implanted and subjected to normal physiologic stresses. The ring elements may be bands of semi-rigid material. A method of repairing an abnormal mitral heart valve annulus having a depressed posterior aspect includes providing a ring with a posterior bow and implanting the ring to support the annulus without unduly stressing the attachment sutures.

An intravascular stent assembly for implantation in a body vessel, such as a coronary artery, includes undulating circumferential rings having peaks on the proximal end and valleys on the distal end. Adjacent rings are coupled together by links. The rings and links are arranged so that the stent has good conformability as it traverses through, or is deployed in, a tortuous body lumen. The stent is also configured such that the likelihood of peaks and valleys on adjacent rings which point directly at each other to overlap in tortuous body vessels is reduced.

Several methods and apparatus are available for treating patients that suffer from both gastro-esophageal reflux disorder and hiatal hernias. In order to treat these patients, an endoscopic probe may be used to push the herniated stomach below the diaphragm. In some embodiments, a two-part stent comprising a funnel stent and a reverse stent may be deployed to prevent a future re-herniation of the stomach and to reduce the annulus of the lower esophageal sphincter. In some embodiments, a reverse stent with perforating barbs may be deployed, in which the barbs penetrate the esophageal wall and attach to the diaphragm. In some embodiments, the crus muscles may be sutured together to reduce the hiatus size and a reverse stent may be deployed to reduce the annulus of the lower esophageal sphincter.

An intravascular stent assembly for implantation in a body vessel, such as a coronary artery, includes undulating circumferential rings having peaks on the proximal end and valleys on the distal end. Adjacent rings are coupled together between peaks on one ring and valleys on the proximally adjacent ring. To increase flexibility of the stent, the links do not couple all of the peaks on a ring to the proximally adjacent ring.

A mitral annuloplasty ring with an inner core and an outer band located therearound is disclosed. The ring has an anterior region, a posterior region opposite the anterior region, and two side regions therebetween. A cross-sectional width dimension of the outer band is greater in the posterior region of the ring than in the anterior region. A cross-sectional width dimension of a semi-flexible core is thinner in the anterior and posterior regions than in the side regions so that the mitral ring is more rigid in the anterior-posterior direction. A tricuspid annuloplasty ring of the invention has an inner core and an outer band located therearound. The inner core has an anterior region separated across a gap from a septal region, and a posterior region. A cross-sectional width dimension of the outer band is greater in the septal region than either the anterior or posterior regions.

An anatomically approximate prosthetic heart valve includes dissimilar flexible leaflets, dissimilar commissures and / or a non-circular flow orifice. The heart valve may be implanted in the mitral position and have one larger leaflet oriented along the anterior aspect so as to mimic the natural anterior leaflet. Two other smaller leaflets extend around the posterior aspect of the valve. A basic structure providing peripheral support for the leaflets includes two taller commissures on both sides of the larger leaflet, with a third, smaller commissure between the other two leaflets. The larger leaflet may be thicker and / or stronger than the other two leaflets. The base structure defines a flow orifice intended to simulate the shape of the mitral annulus during the systolic phase. For example, the flow orifice may be elliptical. A relatively wide sewing ring has a contoured inflow end and is attached to the base structure in such a way that the valve can be implanted in an intra-atrial position and the taller commissures do not extend too far into the left ventricle, therefore avoiding injury to the ventricle.

A multi-lumen catheter comprising a loop-like structure at the distal portion of the catheter is disclosed herein. In one variation, the loop-tip catheter comprises a dual lumen catheter and a loop-like structure at the distal end of the catheter. The loop-like structure includes at least one lumen, which is in fluid communication with at lease one of the two lumens in the dual lumen catheter. One or more ports are provided on the loop-like structure for accessing the lumens within the loop. In another variation, the loop-tip catheter is configured with an arterial inlet positioned on an inner surface of the loop, while a venous outlet is positioned on an outer surface of the loop. Methods for making and using variations of the loop-tip catheter are also disclosed herein.

A prosthetic aortic valve is designed to be implanted in the natural aortic annulus and to extend into the ascending aorta to a point short of the right and left coronary arteries. Blood leakage around the valve is prevented by tension in one or more circumferential cords drawing annular tissue into sealing contact with an external sealing ring on the valve body. The security of the valve's attachment to a patient is assured with a plurality of interrupted sutures between a semirigid flange on the valve outer surface and the patient's aortic commissures and / or the patient's ascending aortic wall. The sutures are preferably attached to posts or cleats on the semirigid sewing flange, the flange being spaced apart from the valve inlet by the sealing ring.

A sewing ring (12) has a diameter commensurate with a diameter of a removed mitral valve. Skirts (44, 46) of mesh or net material extend downward from the sewing ring and line the walls of an associated vessel (58). Basal chordae simulating structures (34, 36) in the form of elongated strips of mesh or netting, rods, or the like extend from the skirt to an underside of each of two valve leaflets (14, 16). Marginal chordae simulating structures (30, 32) extend between each leaflet and the basal chordae simulating structure. The sewing ring (12) is stitched to an open end of a vessel and inner ends of the basal chordae simulating structure are stitched or stapled (50, 52) to associated papillary musculature (54, 56). In this manner, the papillary muscles assist in controlling the timing and control of the mitral valve.

A system for treating mitral valve regurgitation includes a tensioning device having a flexible annuloplasty ring, a plurality of anchoring members and a tensioning filament attached to the flexible ring. One embodiment of the invention includes a method for attaching a flexible annuloplasty ring to the annulus of a mitral valve, and adjusting the lengths of segments of the tension filament attached to the flexible ring in order to exert force vectors on the annulus, thereby reshaping the mitral valve annulus so that the anterior and posterior leaflets of the mitral valve close completely during ventricular contraction.

At the present time, physicians often treat patients with atrial fibrillation (AF) using radiofrequency (RF) catheter systems to ablate conducting tissue in the wall of the Left Atrium of the heart around the ostium of the pulmonary veins. These systems are expensive and take time consuming to use. The present invention circular ablation system CAS includes a multiplicity of expandable needles that can be expanded around a central axis and positioned to inject a fluid like ethanol to ablate conductive tissue in a ring around the ostium of a pulmonary vein quickly and without the need for expensive capital equipment. The expansion of the needles is accomplished by self-expanding or balloon expandable structures. The invention includes centering means so that the needles will be situated in a pattern surrounding the outside of the ostium of a vein. Also included are members that limit the distance of penetration of the needles into the wall of the left atrium, or the aortic wall. The present invention also has an important application to ablate tissue around the ostium of one or both renal arteries, for the ablation of the sympathetic nerve fibers and / or other afferent or efferent nerves going to or from each kidney in order to treat hypertension.

Loop structures for positioning diagnostic an therapeutic elements on the epicardium or other organ surface.

A bifurcated stent graft section includes a plurality of loops formed from a serpentine support wire forming a stent at a distal end of one of the short legs of the bifurcated stent graft section. A delivery system includes a coil having a wire configured to pass through the loops and prevent disengagement of the loops from the delivery system without relative rotational movement between the coil and the loops. In a method for delivery the bifurcated stent graft section, the bifurcated stent graft section is advanced to the treatment site, a sheath is retracted to deploy the proximal end of the bifurcated stent graft section while the coil retains the distal end of one of the short legs of the bifurcated stent graft section. A second guidewire is threaded into the short leg of the bifurcated stent graft section which is been stabilized by being held by the coil of the delivery system. An extension leg graft is delivered over the second guidewire and deployed to be coupled to the other short leg of the bifurcated stent graft section while the coil retains the loops. The coil is rotated to release the loops and allow the bifurcated stent graft section to fully deploy. A second extension leg graft is delivered and coupled to the other leg of the bifurcated stent graft section to complete the construction of a bifurcated stent graft in situ.

An “all-inside double-bundle” ACL reconstruction technique, according to which two femoral sockets and two closed tibial sockets are provided to accommodate retrograde fixation of two grafts (for example, two semitendonosus allografts) within the four sockets. At least one of the tibial sockets is formed by using a retrograde drill device provided with a retrograde drill cutter detachable from a retrograde drill guide pin. The femoral tunnels or sockets may be formed by the retrograde drill method or by a conventional method, and may be carried out before or after the formation of the tibial sockets. The grafts (for example, two semitendonosus allografts) are secured in the knee by employing a continuous loop / button construct provided with a button, preferably of titanium alloy, and a continuous loop of suture attached to the button.

A surgical instrument that creates a circular cut 42 of almost any diameter in the lens capsule 50 of the eye, yet its entire diameter is less than 1 mm when inserted into the eye. A cutting edge 14 is affixed to the distal tip of a super-elastic rod 11 with its distal end formed into a circular loop. The circular loop is first retracted inside of an outer tube member 12, and then the tube 12 is inserted into the eye. The loop is then expelled from the tube 12, allowing the loop to reform inside of the eye. As the loop is retracted back into the tube 12, the cutting edge 14 follows the circular path of the loop, cutting a circular opening (a capsulorrhexis) 42, into the lens capsule 50.

An intravaginal fertilization and culture container includes a main chamber and a microchamber. A culture medium, one or more oocytes and sperm are introduced through an access opening having an associated resealable closure device. The container is enveloped in a capsule of soft elastic material prior to lodgment in the posterior fornix. A loop on one capsule part adapts the length to anatomic variations. The microchamber has a channel which receives the catheter tip to facilitate embryo retrieval while eliminating risk of injury thereto. The microchamber permits embryos to be microscopically inspected in situ before transfer to the uterine cavity.

A jacket of biological compatible material has an internal volume dimensioned for an apex of the heart to be inserted into the volume and for the jacket to be slipped over the heart. The jacket has a longitudinal dimension between upper and lower ends sufficient for the jacket to surround a lower portion of the heart with the jacket surrounding a valvular annulus of the heart and further surrounding the lower portion to cover at least the ventricular lower extremities of the heart. The jacket is adapted to be secured to the heart with the jacket surrounding at least the valvular annulus and the ventricular lower extremities. The jacket is adjustable on the heart to snugly conform to an external geometry of the heart and assume a maximum adjusted volume for the jacket to constrain circumferential expansion of the heart beyond the maximum adjusted volume during diastole and to permit unimpeded contraction of the heart during systole.

The invention is directed to an expandable stent for implanting in a body lumen, such as a coronary artery, peripheral artery, or other body lumen. The invention provides for an intravascular stent having a plurality of cylindrical rings connected by undulating links. The stent has a high degree of flexibility in the longitudinal direction, yet has adequate vessel wall coverage and radial strength sufficient to hold open an artery or other body lumen. The stent can be compressed or crimped onto a catheter to a very low profile since the peaks that are adjacent the curved portion of the undulating link are shorter than other peaks in the same cylindrical ring to prevent overlap yet still achieve a very low profile, tightly crimped stent onto a catheter.

The present invention relates to a device and method which may be used to reinforce the native annulus during spinal surgery. The device is a catheter based device which is placed into the inter-vertebral space following discectomy performed by either traditional surgical or endoscopic approaches. The distal end of the catheter is comprised of an expansile loop which may be increased in diameter by advancement of a portion of the catheter via its proximal end, such proximal end remaining external to the body. The expansile loop may be formed such that when the loop is diametrically contracted the loop feeds into its other end, similar to a snake eating its own tail. Stabilization of the outer portion of the loop and pulling out the inner portion will thereby increase the overall diameter of the loop while maintaining it as a closed loop or torus. The expansile loop then uses an attachment means to secure it to substantially healthy tissues of the annulus, nucleus, or endplates. The present invention comprises four embodiments and can be used to 1) facilitate disk fusing, 2) perform an artificial replacement of the nucleus, 3) perform an artificial replacement of the annulus, or 4, perform an artificial replacement of both the nucleus and annulus.

An endoluminal prosthesis for treating a diseased portion of the ascending aorta includes a tubular graft material having an outer surface and an inner surface and a support structure coupled to the graft material. An anchoring device is coupled to the proximal end of the support structure to engage the sinotubular junction or the sinuses adjacent the sinotubular junction. The anchoring device may be a stent ring with barbs on an outer surface to engage the sinotubular junction, a plurality of anchors extending into the sinuses including hooks to engage the sinuses, a plurality of bent stents with distally facing shoulders extending into the sinuses and engaging a distal edge of the sinuses, or a series of progressively larger diameter stent rings extending into the sinuses to engage the distal edge of the sinuses.

An annuloplasty repair segment for heart valve annulus repair. In one embodiment a multi-stranded cable replaces solid core wire for both the tricuspid and mitral valves. Cable allows for greater deployment flexibility for minimally-invasive surgical (MIS) implant, while still maintaining the required strength and similar tensile properties of solid-core wire. Stranded cable provides a MIS annuloplasty ring with sufficient flexibility in the x-y plane to allow a surgeon to squeeze the ring into a small incision, such as being able to pass through an 18Fr or smaller catheter, while maintaining structural rigidity under forces exerted on the implanted ring by the cardiac cycle. The particular shape of the annuloplasty ring is fixed using a heat setting process.

An expandable stent is implanted in a body lumen, such as a coronary artery, peripheral artery, or other body lumen for treating an area of vulnerable plaque. The invention provides for an intravascular stent having a plurality of cylindrical rings connected by straight links. Alternatively, the cylindrical rings of the distal section and the cylindrical rings of the proximal section are connected directly to adjacent cylindrical rings. The stent has adequate vessel wall coverage and radial strength sufficient to hold open an artery or other body lumen. A central section is positioned between distal and proximal sections and is aligned with the area of vulnerable plaque to enhance growth of cells over the fibrous cap of the vulnerable plaque to reinforce the area and reduce the likelihood of rupture.

A method for percutaneous aortic valve (PAV) replacement and a temporary aortic valve used to facilitate the same. The temporary valve is comprised of a reversibly expandable occluding means, such as balloons, surrounding a central catheter mechanism. The temporary valve is positioned within the ascending aorta, just above and downstream from the coronary ostia. The occluding means is configured such that, when fully expanded against the aortic wall, gaps are left that promote continuous coronary perfusion during the cardiac cycle. The native aortic valve is next dilated, and then ablated through deployment of an ablation stent. The ablation stent displaces the native valve tissues and remains within the aortic annulus to receive and retain the PAV. The PAV can then be positioned and deployed within the ablation stent with precision and ease. Ablation of the native aortic valve removes the structural obstacles to precise PAV placement. The temporary aortic valve mediates the hemodynamic forces encountered by the surgeon following native valve ablation. The temporary valve also promotes patient stability through continuous coronary perfusion and a moderated transvavlular pressure gradient. Mathematical considerations for determining the optimum cross-sectional area for the temporary valve blood perfusion gaps are also described.