Abstract: Disclosed herein is a flexible self-expandable stent using shape memory alloy for expanding stenosal portions and method and apparatus for fabricating the same.

Abstract: An implantable expandable medical device in which selected regions of the device are in a martensite phase and selected regions are in an austenite phase. The martensitic regions exhibit pseudoplastic behavior in vivo and may be deformed without recovery under in vivo body conditions.

Abstract: An endoluminal device, such as a stent or a vena cava filter, comprising at least one superelastic section and at least one plastically deformable section. The superelastic section may comprise, for example, a superelastic grade of nitinol, whereas the plastically deformable section may comprise, for example, gold, platinum, tantalum, titanium, stainless steel, tungsten, a nickel alloy, a cobalt ally, a titanium alloy, or a combination thereof. Each plastically deformable section may merely comprise a constrained portion of the superelastic section comprising a plastically deformable material, such as gold.

Abstract: Nickel-titanium alloys that have been deep drawn in a cold working process have linear pseudoelastic behavior without a phase transformation or onset of stress-induced martensite. A medical device made from a structural element which has been deep drawn and subsequently formed into a desired medical device geometry will experience such linear pseudoelastic behavior.

Abstract: This invention is directed to an intracorporeal device formed of a high strength Co—Ni—Cr alloy and is particularly suitable for forming a composite product with a pseudoelastic member formed of NiTi alloy. Suitable intracorporeal products include guidewires and stents. The high strength alloy consists essentially of about 28 to about 65% cobalt, about 2 to about 40% nickel, about 5 to about 35% chromium, up to about 12% molybdenum, up to about 20% tungsten, up to about 20% iron and the balance inconsequential amounts of impurities and other alloying constituents, with a preferred alloy composition including about 30 to about 45% cobalt, about 25 to about 37% nickel, about 15 to about 25% chromium and about 5 to about 15% molybdenum. Intravascular devices such as guidewires, stents and the like can be formed of this high strength Co—Ni—Cr alloy.

Abstract: A stent or other intraluminal medical device having markers formed from housings integral with the stent and marker inserts having a higher radiopacity than the stent provides for more precise placement and post-procedural visualization in a vessel, by increasing the radiopacity of the stent under X-ray fluoroscopy. The housings are formed integral to the stent and the marker inserts are made from a material close in the galvanic series to the stent material and sized to substantially minimize the effect of galvanic corrosion. The housings are also shaped to minimize their impact on the overall profile of the stent. The stent or other intraluminal medical device may also be fabricated from an alloy having a higher radiopacity without sacrificing any properties of the base alloy forming the stent or other intraluminal medical device.

Abstract: A stent for a vessel implanted in the vessel of the living body including a main body portion of the stent formed into a tube by a yarn formed of a biodegradable polymer exhibiting a shape memory function. The main body portion of the stent is shape-memorized to a size that can be inplanted in the vessel. The main body portion of the stent is implanted in the vessel of the living body as it is contracted in diameter by an external force, and is enlarged in diameter by being heated with the temperature of the living body. The main body portion of the stent is formed by winding a yarn formed of a biodegradable polymer in a tube form as the yarn is bent in a zigzag design. The main body portion of the stent is enlarged or contracted in diameter with the bends of the yarn as the displacing portions.

Abstract: An assembly and method for effecting the condition of a mitral valve annulus of a heart includes a guide wire configured to be fed into the coronary sinus of the heart, and a mitral valve annulus therapy device configured to be slidingly received on the guide wire and advanced into the coronary sinus of the heart on the guide wire. A guide tube may further be employed for guiding the device into the coronary sinus. An introducer which may be employed for pushing the device into or pulling device out of the heart has a mechanism for releasably locking to the device. This enables substitution of the device if needed. Also, the crossover point of the circumflex artery and coronary sinus may be determined and avoided when the device is deployed.

Abstract: An intraluminal prosthesis is provided with a plurality of annular elements. Each annular element includes a plurality of struts and apices connected to form an annular configuration. Each annular element has a compressed state and an expanded state, and has a longitudinal dimension which is smaller in the expanded state than in the compressed state. A plurality of connecting members connect the apices of adjacent annular elements. The connecting members have a plurality of alternating segments that function to compensate for the smaller longitudinal dimension of each annular element in the expanded state. The stent may be provided with varying flexibility along its length and/or circumference, and may include segments that have different diameters.

Abstract: An implantable expandable medical device in which selected regions of the device are in a martensite phase and selected regions are in an austenite phase. The martensitic regions exhibit pseudoplastic behavior in vivo and may be deformed without recovery under in vivo body conditions.

Abstract: A prothesis for transluminal implantation consists of a flexible tubular interbraided structure of metal or polymeric monofilaments, and polymeric multifilament yarns. The prosthesis can be elastically deformed to reduce its diameter through axial elongation. The monofilaments and multifilament yarns are arranged in axially spaced apart helices, concentric on a common central axis of the prosthesis. The monofilaments are selectively shaped before their interbraiding with the multifilament yarns, either by an age-hardening or other heat-setting stage, or a cold-working stage that controllably plastically deforms the strands. The shaped structural strands cooperate to impart to the prosthesis its nominal shape and resilience. The textile strands cooperate to provide a sheeting that occupies interstices between adjacent structural strands, to reduce permeability and thereby enhance the utility of the prosthesis as a vascular graft.

Abstract: A tubular implant having an axial end to which is attached a ring of spoons of a material different from that of the implant. In another aspect, the invention provides a method of attaching elements to an axial end of a tubular implant comprising the steps of providing said elements on one end of a support tube having a radius substantially that of the implant in its unexpanded configuration, abutting the implant and elements end-to-end, fixing the elements to the implant; and parting the elements from the support tube. In a third aspect, the invention provides an implant carrying an element of another material, the element and implant having complementary tapered mating surfaces for achieving a taper form fit of the element onto the implant.

Abstract: A design for a self-expanding intervertebral device is described for use in spinal stabilization. The device is designed to be collapsed into a smaller form for ease of implantation and then re-expand to a larger, final size in order to first distract and then maintain this distraction rigidly once implanted. In all forms of the device, the key design element comprises angled or rounded internal structural members to allow ease of initial deformation. Other key features include no mechanically moving parts, implant is a single piece device, and the device contains a cavity for placement of suitable additional material to augment structural strength or promote bone fusion. The device design is applicable to devices designed for placement between adjacent vertebral endplates or longer (taller) constructs spanning non-adjacent endplates.

Abstract: Devices for excluding aneurysms and treating atherosclerotic disease, for intra-aneurysmal occlusion, and devices for preventing distal emboli. The devices are generally pliable and collapsible thin film devices which can be delivered via a microcatheter into the desired location where they are deployed and undergo either a shape memory phase transformation or in situ polymerization to assume the stable configuration of a permanent endoluminal prosthesis. Prior to being caused to assume their final shape, the devices remain soft, collapsible and pliable to ensure atraumatic delivery through the vascular system. Upon reaching the endoluminal defect in the vessel, the device is extruded from the microcatheter. Devices are also provided for retrieving clots.

Abstract: Devices for excluding aneurysms and treating atherosclerotic disease, for intra-aneurysmal occlusion, and devices for preventing distal emboli. The devices are generally pliable and collapsible thin film devices which can be delivered via a microcatheter into the desired location where they are deployed and undergo either a shape memory phase transformation or in situ polymerization to assume the stable configuration of a permanent endoluminal prosthesis. Prior to being caused to assume their final shape, the devices remain soft, collapsible and pliable to ensure atraumatic delivery through the vascular system. Upon reaching the endoluminal defect in the vessel, the device is extruded from the microcatheter. Devices are also provided for retrieving clots.

Abstract: A stent having a structure differentiated in terms of its stiffness. Such differentiation is achieved with the use of a superelastic material that transitions between a relatively soft and malleable phase to a stiffer phase at a transition temperature that is adjustable. By differentially adjusting the transition temperature of different portions of the stent, a differentiation of the stiffness of the structure is achieved upon the stent being subjected to body temperature.

Abstract: A self-expanding endoluminal device comprising at least one tubular filamentary member having a hollow core for receiving a guidewire, the tubular member having a straightened configuration with the guidewire in the hollow core and a shape memory configuration without the guidewire in the hollow core. A delivery system includes the guidewire. The hollow core may contain a substance that is adapted to be eluted from the tubular member or permanently contained inside. The device may further comprise a graft. The device may also comprise a plurality of filamentary members, more than one of which may comprise tubular members. The device may also have a severable extension that extends outside of the body through which the substance may be periodically injected.

Abstract: A system for treating atrial fibrillation includes a stent and a delivery catheter for carrying the stent to a treatment site. The stent is self-expanding, for example, being formed of a shape memory alloy, and is configured to lodge against the interior wall of a pulmonary vein. The stent may be formed as a loop, helix, progressively wound helix or other suitable shape, and in one embodiment has an exposed proximal portion including an ablation region that contacts and subtends a circumference of the vein, or contacts endocardial wall tissue along a circumferential path at the ostium. The proximal portion is attached to an energy delivery line in the catheter to energize the stent and ablate tissue in the circumferential region, forming a lesion to block conduction across the ostium or preventing trigger signals originating in the pulmonary vein from initiating or sustaining fibrillation in the atrium.

Abstract: A medical device for use within a body lumen that is made from a binary nickel-titanium alloy that remains in its austenitic phase throughout its operational range is disclosed. The medical device, such as an intraluminal stent, is made from superelastic nickel-titanium and may optionally be alloyed with a ternary element. By adding the ternary element and/or through heat treatment, it is possible to lower the phase transformation temperature between the austenitic phase and the martensitic phase of the nickel-titanium alloy. By lowering the phase transformation temperature, the martensite deformation temperature is likewise depressed. It is possible then to depress the martensite deformation temperature below body temperature such that when the device is used in a body lumen for medical treatment, the nickel-titanium device remains completely in the austenitic phase without appearance of stress-induced martensite even if the device is placed under stress.

Abstract: A method of manufacturing medical devices of a size sufficiently small to be passed through the vasculature of the body, and more particularly through the small vessels of the brain. The method includes the steps of laser cutting a pattern of apertures in the surface of a tubular workpiece, radially compressing the tubular workpiece to reduce the outer dimensions of the workpiece and heat setting the reduced diameter workpiece to form the very small medical device.

Abstract: Devices for excluding aneurysms and treating atherosclerotic disease, for intra-aneurysmal occlusion; and devices for preventing distal emboli. The devices are generally pliable and collapsible thin film devices which can be delivered via a microcatheter into the desired location where they are deployed and undergo either a shape memory phase transformation or in situ polymerization to assume the stable configuration of a permanent endoluminal prosthesis. Prior to being caused to assume their final shape, the devices remain soft, collapsible and pliable to ensure atraumatic delivery through the vascular system. Upon reaching the endoluminal defect in the vessel, the device is extruded from the microcatheter. Devices are also provided for retrieving clots.

Abstract: A medical device and a method for providing a change of shape in a part of the body of an organism. The device is insertable into the body of the organism and comprises a member having a preferred state of shape and having a tendency to transfer its shape towards said preferred state of shape when being in a non-preferred state of shape. The device further comprises a resorbable means which is arranged to hold the member in the non-preferred state of shape and to delay the transfer when the device is inserted into the body of the organism by counteracting said transfer during resorption of the resorbable means by the surrounding body of the organism.

Abstract: An improved guiding member for use within a body lumen having a unique combination of superelastic characteristics. The superelastic alloy material has a composition consisting of about 30% to about 52% (atomic) titanium, and about 38% to 52% nickel and may have one or more elements selected from the group consisting of iron, cobalt, platinum, palladium, vanadium, copper, zirconium, hafnium and niobium. The alloy material is subjected to thermomechanical processing which includes a final cold working of about 10 to about 75% and then a heat treatment at a temperature between about 450° and about 600° C. and preferably about 475° to about 550° C. Before the heat treatment the cold worked alloy material is preferably subjected to mechanical straightening. The alloy material is preferably subjected to stresses equal to about 5 to about 50% of the room temperature ultimate yield stress of the material during the thermal treatment.

Abstract: Method for producing a medical support device from an object, using an electromagnetic field generator, whereby the method comprises of the steps of placing a formation mandrel against the object, close to a predetermined formation area, and applying the electromagnetic field to the formation area, thereby forming the object. The produced object can be made from a tubular segment, a folded sheet of material or a plurality of wires joined together.

Abstract: An implantable coil stent comprises at least a first curved segment and a curved segment which arc about the longitudinal axis of the stent. An expandable link extends between the second end of the first curved segment and the first end the second curved segment.

Abstract: A new multiple component stent arrangement which allows for initial self-expansion and subsequent deformation to a final enlarged size. These tissue supporting devices are generally cylindrical or tubular. They have at least one component which is deformable, by an external force, to maintain further expansion.

Abstract: Medical devices may be made of shape-memory materials portions of which have been heat treated to exhibit spatial variations in the stiffness of the material. Devices including stents, vena cava filters and guidewires may be constructed from such materials. Devices may also be made from shape-memory materials which have been locally heat treated such that the superelasticity of the treated portion is destroyed while the remainder of the shape-memory material can transition between the martensitic and austenitic states.

Abstract: A stent for use in a curved body lumen is disclosed. The stent is made from a superelastic alloy such as nickel titanium or nitinol, and optionally includes a ternary element. The superelastic alloy has a low temperature phase or martensitic phase and a high temperature phase or an austenitic phase. In the high temperature phase, the stent has a curve along the length that closely matches the curve of the vessel in the patient's anatomy. When deployed in the curved vessel of the patient, the heat set curve of the stent closely conforms to the curvature in the vessel and minimizes trauma and stress to the vessel.

Abstract: The present invention relates to resin composition with superior antioxidant properties, mechanical strength and insulating properties. A mixture of a thermoplastic resin in pellet or granular form and water is heated under pressure at a subcritical condition of the water to melt the thermoplastic resin, and the melted resin is cooled.

Abstract: Segmented articulatable stent of open structure comprised of end-connected struts making up the segments with angular interconnects between segments.

Abstract: A stent for a vessel implanted in the vessel of the living body including a main body portion of the stent formed into a tube by a yarn formed of a biodegradable polymer exhibiting a shape memory function. The main body portion of the stent is shape-memorized to a size that can be inplanted in the vessel. The main body portion of the stent is implanted in the vessel of the living body as it is contracted in diameter by an external force, and is enlarged in diameter by being heated with the temperature of the living body. The main body portion of the stent is formed by winding a yarn formed of a biodegradable polymer in a tube form as the yarn is bent in a zigzag design. The main body portion of the stent is enlarged or contracted in diameter with the bends of the yarn as the displacing portions.

Abstract: The present invention provides radially-expandable stents that, in various embodiments, may reduce the bending stresses/strains associated with the compressed state of self-expanding stents and/or may prevent longitudinal expansion/contraction of radially expandable stents between the compressed and expanded states. In addition, stents according to the present invention preferably exhibit increased longitudinal flexibility in both the compressed and expanded states. The present invention also includes delivery systems in which threading of the guidewire through the delivery system may be simplified. In addition, the delivery systems according to the present invention may also incorporate a balloon to assist in radially expanding the stent and/or seating of the stent in the lumen during deployment without removing the stent delivery catheter.

Abstract: The present invention provides stents for deploying within tubular organs, blood vessels, or other tubular body lumens. Such stents comprise a stent body comprising an elastic material, the stent body being characterized by a free cylindrical shape having a free diameter. The stent body is at least partially covered with a covering that substantially prevents the stent body from expanding towards its free diameter when the stent body is placed into a diameter smaller than the free diameter. In one embodiment, the covering is a metal coating on the stent body. In another embodiment, the covering is a tube, or multiple tubes, around the stent body. Also provided is a method for deploying the stents of the present invention within tubular organs, blood vessels, or other tubular body lumens.

Abstract: A device and method of use for a partial occlusion device (POD) for matter and liquid flow control. More specifically, a device relating to the partial occlusion of blood vessels to affect the flow of blood through the blood vessels is disclosed. The POD may be formed from a mesh material and includes one or more lumens. The POD may be particularly useful in treating Hypoplastic Left Heart Syndrome, by reducing pulmonary blood flow to decrease the risk of pulmonary hypertension. The POD may also be used to deliver therapeutic agents to a specific site. The POD can be retrieved after placement.

Abstract: A stent for a vessel implanted in the vessel of the living body including a main body portion of the stent formed into a tube by a yarn, which is formed of a biodegradable polymer, exhibiting a shape memory function. The main body portion of the stent is shape-memorized to a size that can be implanted in the vessel. The main body portion of the stent is implanted in the vessel of the living body as it is contracted in diameter by an external force, and is enlarged in diameter by being heated with the body temperature of the living body. The main body portion of the stent is formed by winding a yarn formed of a biodegradable polymer in a tube form as the yarn is bent in a zigzag design. The main body portion of the stent is enlarged or contracted in diameter with the bends of the yarn as the displacing portions.

Abstract: The coated superelastic stent is formed from a tube of collagen having an inner structure of a micro-cable made of strands of a material exhibiting super-elasticity or shape memory properties, such as nickel-titanium, and includes a strand of radiopaque material, such as platinum or gold, in order to provide a radiopaque marker during interventional therapeutic treatment or vascular surgery. The collagen tube can be loaded with a therapeutic agent for treatment of the desired site in the vasculature.

Abstract: A radially self-expanding implantable intraluminal device formed from a hollow tubular braid. The intraluminal device may be used in a variety of medical procedures which require a passageway to be maintained in an open position or which require reinforcement, support or a bypass conduit such as in blood vessels weakened by disease. The intraluminal device is longitudinally expanded or radially collapsed for ease of insertion into a lumen and upon alignment within the lumen, the intraluminal device radially self-expands to come into intimate contact with the inner surface of the lumen.

Abstract: Medical devices may be made of shape-memory materials portions of which have been heat treated to exhibit spatial variations in the stiffness of the material. Devices including stents, vena cava filters and guidewires may be constructed from such materials. Devices may also be made from shape-memory materials which have been locally heat treated such that the superelasticity of the treated portion is destroyed while the remainder of the shape-memory material can transition between the martensitic and austenitic states.

Abstract: The hinge stent is a balloon-expandable or self-expandable intravascular endoprosthesis used for treatment of vascular injury. The hinge stent is formed of a single stent section or of multiple stent sections joined together. Each stent section has a node and strut structure extending throughout in order to uncouple expansion forces of the stent to hold a blood vessel outward from crush forces that resist the formation of an oval shape during a crush deformation. Each node includes a hinge which is joined via a transition region to a strut. The hinge can bend in the direction of a uniformly curved surface of the stent but not in the radial direction. The strut can bend in the radial direction but not in the uniformly curved surface of the stent. The widths, lengths, and radial dimensions of the hinges and struts provide a balloon-expandable hinge stent that is non-crushable. For a self-expandable stent the hinge and strut dimensions provide expansion forces that are controlled independently from crush forces.

Abstract: The present invention provides a self-expanding tubular stent comprising a plurality of stent segments. Each stent segment is formed of an elongate ribbon having portions cut therefrom to form a wave-like undulating pattern, opposed edges of which are attached to one another so as to form a generally cylindrical configuration. A disclosed method effects formation of such an expandable tubular stent by first providing an elongate flat ribbon of biocompatible stent material and selectively removing portions of such material to form an undulating wave-like pattern along the length of the ribbon. The ribbon is then coiled into a generally cylindrical configuration and opposed ends of the ribbon are secured to one another to form a generally cylindrical and expandable spiral stent section. After forming a plurality of such stent sections, the stent sections are arranged in longitudinal succession and interconnected so as to form an elongated stent configuration.

Abstract: An implantable coil stent comprises at least a first curved segment and a curved segment which arc about the longitudinal axis of the stent. An expandable link extends between the second end of the first curved segment and the first end the second curved segment.

Abstract: Intravascular devices and methods are provided for forming a vascular graft by axially distending a blood vessel to induce growth. These devices advantageously can be implanted via a catheter, thereby eliminating the need for a more invasive implantation procedure when the stretching is to be done in vivo. Preferably, the device for axially distending a blood vessel to induce growth of the vessel includes an intravascular stretching mechanism attachable directly to an interior lumen portion of the blood vessel, and a means for operating the stretching mechanism to cause the vessel to distend axially. The stretching mechanism can include a pair of wires or stents that engage the blood vessel wall. Components of the stretching mechanism can include a shape memory material.

Abstract: A stent and catheter for implanting or removing a helical-shaped stent within a body passageway; the catheter having an elongate sheath capable of being secured to one end of the stent at a distal region of the sheath and an inner member extending from the sheath, and capable of being secured to the other end of the stent. The inner member is rotatable relative to the sheath to transmit torque to the stent to permit unwinding of the helical stent as its limiting strain to expand the stent. Also discussed are methods for performing procedures for implanting or removing a helical stent from a body passageway.

Abstract: This invention is directed to an intracorporeal device formed of a high strength Co—Ni—Cr alloy and is particularly suitable for forming a composite product with a pseudoelastic member formed of NiTi alloy. Suitable intracorporeal products include guidewires and stents. The high strength alloy consists essentially of about 28 to about 65% cobalt, about 2 to about 40% nickel, about 5 to about 35% chromium, up to about 12% molybdenum, up to about 20% tungsten, up to about 20% iron and the balance inconsequential amounts of impurities and other alloying constituents, with a preferred alloy composition including about 30 to about 45% cobalt, about 25 to about 37% nickel, about 15 to about 25% chromium and about 5 to about 15% molybdenum. Intravascular devices such as guidewires, stents and the like can be formed of this high strength Co—Ni—Cr alloy.

Abstract: A tubular graft/stent comprises a tubular sheath having at intervals along its length a plurality of ring-like rigid members, which are attached to the sheath around their respective circumferences and are made of a shape memory material, so that when the members change shape the sheath adopts a new cross section in conformity with the members along the sheath's whole length. The members may be discontinuous to allow the adoption of a contracted shape in the martensitic phase and an expanded shape in the austenitic phase. A graft may also have a branched side tube which can be inverted so as to be housed within the sheath.

Abstract: The diamter of &bgr;-titanium alloy wire is reduced by cold wire-drawing and the &bgr;-titanium alloy wire is subjected to heat treatment. The heat treatment comprises the first aging process for precipitation strengthening and the second aging process for removing processing strain. &bgr;-titanium alloy wire is heat-treated under the supply of tension at the second aging process.

Abstract: The invention provides a means of boosting the mechanical performance of shaped shaped medical devices comprising polymer hydrogels, such as stents, so that they may be more easily inserted into or removed from the body. In one aspect, the invention provides shaped medical devices having increased mechanical strength and comprising both ionic and covalent crosslinks. In another aspect, the invention provides a shaped medical device having a heterogeneous polymer composition and a variable dissolution or degradation rate along its length. The shaped medical devices according to the present invention retain their shape and stiffness during insertion into the body and can swell and soften inside the body to enhance patient comfort.

Abstract: Implantable connector devices which are useable to maintain fluidic connection between, or approximation of, openings formed in adjacent natural or prosthetic anatomical conduits (or adjacent openings formed in a single anatomical conduits). These connector devices generally comprise a plurality of radially expandable annular members having one or more elongate strut members extending therebetween. Initially, the device is mountable on or within a delivery catheter while in a radially compact configuration. After the delivery catheter has been inserted into the body, the device is caused to transition to a radially expanded configuration whereby it becomed implanted within the body so as to maintain the desired fluidic connection between, or the desired approximation of, the anatomical conduit(s).

Abstract: A radially self-expanding implantable intraluminal device formed from a hollow tubular braid. The intraluminal device may be used in a variety of medical procedures which require a passageway to be maintained in an open position or which require reinforcement, support or a bypass conduit such as in blood vessels weakened by disease. The intraluminal device is longitudinally expanded or radially collapsed for ease of insertion into a lumen and upon alignment within the lumen, the intraluminal device radially self-expands to come into intimate contact with the inner surface of the lumen.

Abstract: The invention provides a tubular expandable stent including a plurality of cylindrically shaped open cylindrical segments aligned on a common longitudinal axis to define a generally tubular stent body, each segment being defined by a member formed in an undulating flexible pattern of interconnected substantially parallel struts with pairs thereof having alternating interconnecting end portions to define the periphery of the expandable stent segment, and in which the connected end portions of paired struts in each segment, before the stent is expanded, are positioned substantially opposite to connected end portions of paired struts in adjacent segments.