Abstract: To improve the re-wrappability of the expander members used on balloon catheters subsequent to an initial inflation thereof, the balloon member is subjected to an annealing process in which the balloon member, in its wrapped configuration, is placed within a plastic sheath and it, together with the sheath, is then placed between the jaws of a clamping fixture where the jaws may be heated to a predetermined temperature. When the jaws are made to close on the sheath and the wrapped balloon contained within it, the wrapped balloon is subjected to a radial compressive pressure and a temperature approximately equal to or above the glass transition temperature for the balloon material utilized and then maintained at that temperature for a predetermined time interval. The annealing is found to introduce a memory component into the plastic of the balloon that causes it to assume a lower profile upon deflation than otherwise obtained.

Abstract: A body compatible stent is formed of multiple filaments arranged in two sets of oppositely directed helical windings interwoven with one another in a braided configuration. Each of the filaments is a composite including a central core and a case surrounding the core. In the more preferred version, the core is formed of a radiopaque and relatively ductile material, e.g. tantalum or platinum. The outer case is formed of a relatively resilient material, e.g. a cobalt/chromium based alloy. Favorable mechanical characteristics of the stent are determined by the case, while the core enables in vivo imaging of the stent. The composite filaments are formed by a drawn filled tubing process in which the core is inserted into a tubular case of a diameter substantially more than the intended final filament diameter. The composite filament is cold-worked in several steps to reduce its diameter, and annealed between successive cold-working steps.

Abstract: A device for deploying radially self-expanded stents and other radially expandable stents includes an inner catheter, an outer catheter surrounding the inner catheter, and a tubular stent retaining sheath formed of a rolling membrane. The sheath is doubled over upon itself to provide an inner sheath layer attached to the inner catheter, and an outer sheath layer attached to the outer catheter. The sheath layers extend along and surround a radially self-expanding stent, to maintain the stent distally of the inner catheter and in a radially compressed, axially elongated state. Distally of the stent, the inner and outer sheath layers converge and are narrowed in the distal direction to define a tapered distal tip. To release the stent, the outer catheter is moved proximally to roll the membrane away from its surrounding relation to the stent, whereupon the stent radially self-expands progressively, beginning at its distal end.

Abstract: A process for preparing coating compositions of a commingled hydrogel of a polyurethane-polyurea polymer hydrogel and a poly(N-vinylpyrrolidone) polymer hydrogel; a process for making materials composed of a polymeric plastic or rubber substrate or a metallic substrate, with a coating of the commingled hydrogel thereon; and a process for making medical devices with a coating of the commingled hydrogel thereon, are disclosed. The coating compositions tenaciously adhere to the substrate materials and medical devices to which they are applied due to bonding of a tie coat to a reactive substrate surface and due to the commingling of the two hydrogel components. The coating compositions and coated materials and medical devices are non-toxic and biocompatible, making them ideally suited for use in applications such as for catheters, catheter balloons and stents.

Abstract: A balloon catheter includes an inflatable expander member for deploying a large diameter stent includes a plurality of balloon segments affixed to the distal end of a multi-lumen catheter body, the segments being selectively expansible in groups whereby the stent can be spread to conform to the blood vessel in which it is deployed while still permitting blood to perfuse through the spaces occupied by the uninflated ones of the segments. By using plural segments of smaller effective diameter, the composite expander can be made large enough to spread a collapsed stent without exceeding the burst strength of the individual balloon segments.

Abstract: A catheter for use in angioplasty and other medical procedures is disclosed. The catheter features a flexible-wire mesh tip movably attached at a distal end of the catheter, the tip being expandable from a contracted position which it is first in when the catheter is deployed inside the lumen of a vessel, to stretch open the lumen and eliminate a flow obstruction therein, such as is caused by plaque deposits; the tip subsequently being returnable to its contracted position inside the catheter when the catheter is withdrawn from the lumen of the vessel. Radio frequency energy may additionally be used to weld the source of the flow obstruction to the wall of the lumen leaving a conduit of sufficiently expanded diameter to allow resumption of normal flow in the vessel.

Abstract: A radially self-expanding stent having multiple layers includes a medial region and proximal and distal cuffs having diameters greater than the medial region diameter when the stent is in the relaxed state. A silicone coating circumscribes at least the medial region of the stent. A deployment device for the stent includes an inner tube surrounded by the stent along with an outer tube that radially compresses the stent. A low durometer sleeve, fixed to the inner tube and in surface engagement with the compressed stent, tends to fix the axial position of the stent relative to the inner tube whenever the outer tube is moved axially relative to the inner tube. Consequently, precision in stent placement and the ability to recapture a partially deployed stent are enhanced.

Abstract: A body compatible stent is formed of multiple filaments arranged in at least two sets of oppositely directed helical windings interwoven with one another in a braided configuration. Each of the filaments is a composite including a central core and a case surrounding the core. In the more preferred version, the core is formed of a radiopaque and relatively ductile material, e.g. tantalum or platinum. The outer case is formed of a relatively resilient material, e.g. a cobalt/chromium based alloy. Favorable mechanical characteristics of the stent are determined by the case, while the core enables in vivo imaging of the stent. The composite filaments are formed by a drawn filled tubing process in which the core is inserted into a tubular case of a diameter substantially more than the intended final filament diameter. The composite filament is cold-worked in several steps to reduce its diameter, and annealed between successive cold-working steps.

Abstract: A body compatible stent is formed of multiple filaments arranged in two sets of oppositely directed helical windings interwoven with one another in a braided configuration. Each of the filaments is a composite including a central core and a case surrounding the core. In the more preferred version, the core is formed of a radiopaque and relatively ductile material having a linear attenuation coefficient of at least 25 cm.sup.-1 at 100 KeV, e.g. tantalum or platinum. The outer case is formed of a relatively resilient material, e.g. a cobalt/chromium based alloy. Favorable mechanical characteristics of the stent are determined by the case, while the core enables in vivo imaging of the stent. Alternative composite filaments employ an intermediate barrier layer between the case and core formed for example of tantalum, niobium or platinum. To improve compatibility, a biocompatible cover layer can surround the case.

Abstract: A medical device such as a catheter is described having a stiff, preferably metallic, proximal tube. The distal portion of the proximal tube may have a plurality of perforations or slots formed therein to increase its flexibility. This provides a smooth transition between the relatively stiff proximal tube and a more flexible distal polymeric tube.

Abstract: A diagnostic catheter comprises an inner layer of substantially unmodified polyamide over which is a reinforcing means and an outer layer of polymer having a hardness of 50 Shore D to 70 Shore D, along with a suitable radiopaque filler. Affixed either directly to the end of the above tubular body or to a stem member secured to that tubular body is a soft-tip formed from a blend of PEBA whose hardness is such that the catheter can be Considered as having an atraumatic tip. The resulting catheter exhibits excellent torque and column strength characteristics while providing a relatively large diameter lumen for a given outside diameter.

Abstract: A percutaneous stent-graft is disclosed for restoring blood flow between vessels. The stent-graft has a body implantable device and first and second peel-away retaining elements. Also disclosed are methods for deploying a stent-graft.

Abstract: A non-coextrusion process for making multi-layer angioplasty balloons involves pre-forming separate parisons and then concentrically disposing the plural parisons to form a composite parison which is then subjected to a blow-molding process. The resulting balloon can have its properties tailored by appropriate selection of the particular plastics to be used for the multiple parisons.

Abstract: A process for preparing coating compositions of a commingled hydrogel of a polyurethane-polyurea polymer hydrogel and at least one other polymer hydrogel of a polymer different from polyurethane-polyurea; a process for making materials composed of a polymeric plastic or rubber substrate or a metallic substrate, with a coating of the commingled hydrogel thereon; and a process for making medical devices with a coating of the commingled hydrogel thereon, are disclosed. The coating compositions tenaciously adhere to the substrate materials and medical devices to which they are applied due to bonding of a tie coat to a reactive substrate surface and due to the commingling of the two hydrogel components. The coating compositions and coated materials and medical devices are non-toxic and biocompatible, making them ideally suited for use in applications such as for catheters, catheter balloons and stents.

Abstract: The present invention provides a compression device for selectively applying compressive force to a localized area of interest on the surface of a body that is readily positioned and fastened in place. The device includes a resilient compressible element positioned on a relatively rigid member associated with a clamping frame that at least partially surrounds a limb or other body area of interest. An adjustable closure means is provided for adjustably completing the clamp arrangement to completely enclose said bodily region of interest in a manner that enables the compressible element to be applied to the precise site of interest. The adjustable closure element permits accommodating bodily parts such as limbs of various size and facilitates adjustment of the compressive pressure applied. The device may take a variety of embodiment forms.

Abstract: This invention relates to a drug delivery device having a hollow tube which is configured to serve as a guide wire for intraluminal procedures. The distal portion of the tube has at least one opening which has a diameter suitable for the infusion of a drug formulation therethrough. The tube is preferably formed from a superelastic material such as nickel-titanium alloy. This invention also relates to various methods of using this drug delivery device in thrombolytic and other intraluminal procedures.

Abstract: An intravascular catheter having an elongated tubular body with a proximal portion, a distal portion and a lumen extending therebetween. The tubular body is formed with: (a) an inner layer of a blend of (i) about 10-25 weight percent of a polyester-polyurethane having a durometer of from about 45D-55D, and (ii) about 38-53 weight percent of a polyester polyurethane having a durometer of from about 65D-75D; (b) a reinforcing means at least partially surrounding the inner layer; and (c) an outer layer comprising a blend of (i) about 10-25 weight percent of a polyester-polyurethane having a durometer of from about 45D-55D and (ii) about 38-53 weight percent of a polyester-polyurethane having a durometer of from about 659D-75D.

Abstract: An apparatus includes a flexible tubular member containing a shape-memory tube formed to include a lumen extending along the central axis of the tubular member. A liner sleeve extends through the lumen of the shape-memory tube and lies inside the tubular member. A control system selectively heats the shape-memory tube to its activated state causing the shape-memory tube to move toward a predetermined shape if it is different than its present configuration. Whether the shape-memory tube moves or not, it will increase significantly in stiffness, both axial and bending to help retain, hold, or wedge the apparatus in place in a selected body cavity while catheters or other objects are passed through a lumen in the liner sleeve.

Abstract: A guidewire for placement within a blood vessel for penetrating an occlusion therein. The guidewire comprises a length of flexible wire having a lumen extending therethrough. The distal end of the guidewire is generally arcuate and has a diameter greater than that of the wire immediately proximal thereto. A flexible stylet substantially the same length as the flexible wire may be disposed within the lumen of the wire. In operation, the arcuate distal end of the guidewire is positioned in the blood vessel against an occlusion, and a dottering action is thereafter provided whereby the arcuate distal end of the guidewire repeatedly impinges on the occlusion until penetration of the occlusion occurs.

Abstract: Catheters for drug delivery or for both dilatation and drug delivery are provided with a guide wire lumen terminating within the catheter shaft and having an opening through the catheter shaft to enable a guide wire to exit the catheter shaft substantially distal to the proximal end of the catheter. In one embodiment, drug delivery ports are provided between occlusion balloons. In another embodiment, a dilatation balloon is also provided between the occlusion balloons. In another embodiment, a double layered balloon is provided to simultaneously dilatate the stenosis and deliver medication to the site. Alternatively, a balloon can be provided which only delivers medication.