Abstract: An inflatable dilatation device includes: (i) a tubular frame including a first frame member that zigzags circumferentially; and (ii) an elongate inflatable first balloon. The elongate inflatable first balloon: (i) is secured to the first frame member; and (ii) zigzags along the first frame member, such that inflation of the first balloon causes the first balloon and the first frame member circumferentially to expand in unison from a contracted condition to an expanded condition.

Abstract: An expandable sleeved stent comprises a stent and a sleeve. The stent comprises a tubular body with: first and second axial ends; a latticed peripheral wall; and at least two arms that, upon radial expansion of the tubular body from a crimped condition to an expanded condition, protrude radially from the latticed peripheral wall, the free end of each arm being radially displaceable relative to the adjacent latticed peripheral wall. The sleeve: (a) extends from the first axial end of the tubular body and circumferentially covers at least a portion of the radial outer surface of the latticed peripheral wall between the free ends of the arms and the first axial end of the tubular body; (b) bridges the spaces between the portions of the latticed peripheral wall adjacent the arms; and the free ends of the arms; and (c) is secured to either: (i) the arms; or (ii) the tubular body in the vicinity between the free ends of the arms and the second axial end of the tubular body.

Abstract: A crimping device includes a housing defining a bore and at least three extendable mechanisms angularly equispaced about the axis of the bore. Each of the extendable mechanisms include: (i) a first elongate arm hingedly connected at or near a first axial end of the first arm to the housing; (ii) a second elongate arm hingedly connected at or near a first axial end of the second arm to the housing, wherein: the first axial ends of the first and second arms are displaceable relative to each other; and the first and second arms are hingedly connected at or near their second axial ends to each other.

Abstract: An expandable stent comprises a cylindrical wall made up of lattice members connected to each other, at least one first arm and at least one second arm. The first arm comprises: a first non-linear member that is connected at each of its axial ends to a lattice member at respective first junctions; a second non-linear member connected at each axial end to a lattice member; and at least one bridge member extending between the first member and the second member. The second arm comprises: a first non-linear member that is connected at each of its axial ends to a lattice member; a second non-linear member connected at each axial end to a lattice member; and at least one bridge member extending between the first member and the second member. The second member of the first arm is generally U-shaped, extending from its axial ends towards: (i) a first axial end of the stent; and (ii) towards the bridge of the first arm.

Abstract: A crimping device includes a housing defining a bore and at least three extendable mechanisms angularly equispaced about the axis of the bore. Each of the extendable mechanisms include: (i) a first elongate arm hingedly connected at or near a first axial end of the first arm to the housing; (ii) a second elongate arm hingedly connected at or near a first axial end of the second arm to the housing, wherein: the first axial ends of the first and second arms are displaceable relative to each other; and the first and second arms are hingedly connected at or near their second axial ends to each other.

Abstract: An expandable stent comprises a cylindrical wall made up of lattice members connected to each other, at least one first arm and at least one second arm. The first arm comprises: a first non-linear member that is connected at each of its axial ends to a lattice member at respective first junctions; a second non-linear member connected at each axial end to a lattice member; and at least one bridge member extending between the first member and the second member. The second arm comprises: a first non-linear member that is connected at each of its axial ends to a lattice member; a second non-linear member connected at each axial end to a lattice member; and at least one bridge member extending between the first member and the second member. The second member of the first arm is generally U-shaped, extending from its axial ends towards: (i) a first axial end of the stent; and (ii) towards the bridge of the first arm.

Abstract: Methods for treating xenogenic tissue for implantation into a human body including in-situ polymerization of a hydrogel polymer in tissue, and tissue treated according to those methods, where the polymerization takes place in tissue that has not been fixed with glutaraldehyde. The polymerization may only fill the tissue, bind the polymer to the tissue, or cross-link the tissue through the polymer, depending on the embodiment. One method includes free radical polymerization of a first vinylic compound, and can include cross-linking through use of a second compound having at least two vinyl groups. Another method utilizes nucleophilic addition polymerization of two compounds, one of which can include PEG and can further include hydrolytically degradable regions. In one embodiment, applicants believe the in-situ polymerization inhibits calcification, and that the polymerization of tissue un-fixed by glutaraldehyde allows for improved penetration of the polymer.

Abstract: A vascular prosthesis is constructed from a structure having interconnected, helically oriented channel-porosity to allow oriented ingrowth of connective tissue into a wall of the prosthesis. The prosthesis can have a small internal diameter of 6 mm or less. Several different methods can be used to produce the prosthesis, including a fiber winding and extraction technique, a melt extrusion technique, and a particle and fiber extraction technique using either a layered method or a continuous method. Furthermore, mechanical properties of the prosthesis are matched with mechanical properties of the host vessel, thereby overcoming problems of compliance mismatch.

Abstract: Stents and methods of using stents are provided. Stents of the invention provide external support structure for a blood vessel segment disposed within, wherein the stents are capable of resilient radial expansion in a manner mimicking the compliance properties of an artery. The stent may be formed of a knitted or braided mesh formed so as to provide the needed compliance properties. A venous graft with the stent and a vein segment disposed within is provided, wherein graft is capable of mimicking the compliance properties of an artery. Methods of selecting stents for downsizing and methods of using the stents of the invention in downsizing and smoothening are provided. Methods of replacing a section of an artery with a venous graft including a stent of the invention are provided. Methods of reducing intimal hyperplasia in implanted vein segment in a venous graft using stents of the invention are provided.

Abstract: A method of preparing a polymer involving reacting at least one backbone carbamate (and/or optional urea) nitrogen of a thermoplastic polymer with a modification agent to form a modified polymer.

Abstract: A vascular prosthesis is constructed from a structure having interconnected, helically oriented channel-porosity to allow oriented ingrowth of connective tissue into a wall of the prosthesis. The prosthesis can have a small internal diameter of 6 mm or less. Several different methods can be used to produce the prosthesis, including a fiber winding and extraction technique, a melt extrusion technique, and a particle and fiber extraction technique using either a layered method or a continuous method. Furthermore, mechanical properties of the prosthesis are matched with mechanical properties of the host vessel, thereby overcoming problems of compliance mismatch.

Abstract: A multilayer ingrowth matrix is constructed within well-defined porosity of a prosthetic material. The matrix consists of either proteinaceous or synthetic layers or gradients, or a combination of proteinaceous and synthetic layers or gradients. Each layer within the matrix is designed to achieve a specific function, such as facilitation of ingrowth of a particular cell type or release of a particular growth factor. The well-defined porosity is in the form of either helically oriented, interconnected transmural ingrowth channels, or a porous wall structure containing uniformly shaped pores (i.e. voids) in a very narrow size range, or a combination of channels and pores. This invention allows for uninterrupted ingrowth of connective tissue into walls of a synthetic graft prosthesis made from the prosthetic material. Furthermore, this invention can produce small diameter prostheses having an internal diameter of 6 mm or less.

Abstract: A graft for replacement of a section of an artery and methods of making the graft. The graft comprises a flexible, resilient, generally tubular external support and a blood vessel segment, e.g., a vein segment, carried within and having an ablumenal surface in contact with and supported by the tubular support, the graft being capable of resilient radial expansion in a manner mimicking the radial compliance properties of an artery.

Abstract: A polymeric biomaterial that facilitates cell-specific ingrowth. The polymeric biomaterial encourages the ingrowth of cell types while reducing the ingrowth of undesirable cell types. This activity encourages proper integration of prosthetic implants or scaffolds utilizing this biomaterial by discouraging encapsulation or the accumulation of inflammatory cells such as macrophages, while encouraging infiltration by desirable cells such as endothelial or smooth muscle cells. Short peptide sequences are included in a polymeric biomaterial that result in complementary activities. Peptide sequences that are specifically cleaved by proteases found within preferred cells are used to cross-link the biomaterial and lead to degradation by those cells. Peptide sequences taken from proteins involved in cell adhesion can also be attached to the biomaterial to encourage adhesion by preferred cells. Combined use of both peptides in the polymeric biomaterial provides both specific adhesion and selective ingrowth.

Abstract: Methods for treating xenogenic tissue for implantation into a human body including in-situ polymerization of a hydrogel polymer in tissue, and tissue treated according to those methods, where the polymerization takes place in tissue that has not been fixed with glutaraldehyde. The polymerization may only fill the tissue, bind the polymer to the tissue, or cross-link the tissue through the polymer, depending on the embodiment. One method includes free radical polymerization of a first vinylic compound, and can include cross-linking through use of a second compound having at least two vinyl groups. Another method utilizes nucleophilic addition polymerization of two compounds, one of which can include PEG and can further include hydrolytically degradable regions. In one embodiment, applicants believe the in-situ polymerization inhibits calcification, and that the polymerization of tissue un-fixed by glutaraldehyde allows for improved penetration of the polymer.

Abstract: A venous graft for replacement of a section of an artery and methods of making the graft. The graft comprises a flexible, resilient, generally tubular external support and a vein segment carried within and having an ablumenal surface in contact with and supported by the tubular support, the venous graft being capable of resilient radial expansion in a manner mimicking the radial compliance properties of an artery.

Abstract: A vascular prosthesis is constructed of an inner porous tube which allows uninterrupted cellular growth and which is connected to an adventitial sock surrounding the porous tube. The adventitial sock produces a non-linear elastic response to stress-strain on the prosthesis to optimize compliance and prevent over dilatation.

Abstract: A method of preparing a biological tissue for implantation that has been treated with an aldehyde, the method utilizing a cyclic nonpeptidyl amide-functional and/or imide-functional compound to remove excess aldehyde from the treated biological material, thereby detoxifying the biological tissue.