Patents by Inventor Xiaoping Guo

Xiaoping Guo has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20100168270
    Abstract: The invention relates to biocompatible polycarbonate/polyamide polymer compositions for use in medical and surgical devices. Additional additives, crosslinking agents, phosphites, and optionally a radiopaque filler or fillers can be used to produce the high performance compositions desired. The polymer compositions have improved melt processability along with balanced or enhanced physical and mechanical properties, especially when combined or over-extruded onto or covering other polymer layers, such as soft and/or flexible layers commonly used in medical device applications and catheter tips, for example.
    Type: Application
    Filed: December 31, 2008
    Publication date: July 1, 2010
    Inventors: Xiaoping Guo, David P. Johnson, Richard E. Stehr
  • Publication number: 20090171348
    Abstract: A guidable, or steerable, or deflectable catheter is provided that includes a proximal portion and a distal portion for insertion into a body cavity. A selectively deflectable segment having an anisotropic bending stiffness for deflection in individual planes is incorporated into the distal portion of the catheter shaft. Upon actuation of pull wires, the distal deflectable segment may be deflected to move/sweep the distal catheter tip through a sweeping plane. The anisotropic bending stiffness of the distal deflectable segment permits in-plane movement of the distal catheter tip in the sweeping plane while resisting any out-of-plane movements. In one arrangement, stiffening elements are selectively disposed within the distal deflectable segment such that the out-of-plane bending stiffness is largely increased and greater than the in-plane bending stiffness for deflection in the sweeping plane.
    Type: Application
    Filed: December 28, 2007
    Publication date: July 2, 2009
    Inventors: Xiaoping Guo, Troy T. Tegg, Richard E. Stehr
  • Publication number: 20090171319
    Abstract: A catheter shaft includes an inner layer of a first polymeric material, an intermediate layer of a second polymeric material, an outer layer of a third polymeric material, a first wire reinforcing layer encapsulated between the inner and intermediate layers, and a second wire reinforcing layer encapsulated between the outer and intermediate layers. Typically, the first wire reinforcing layer includes one or more metallic wires helically wound in one direction and the second wire reinforcing layer includes one or more metallic wires helically wound in the opposite direction. The intermediate layer is bonded to the inner and outer layers, as by extruding layers over one another or by thermal lamination or reflow bonding. Typically, the intermediate layer has a larger yield strain and/or a lower flexural modulus and/or a lower durometer than at least one of the inner layer and the outer layer.
    Type: Application
    Filed: December 30, 2007
    Publication date: July 2, 2009
    Inventors: Xiaoping Guo, David P. Johnson, Richard E. Stehr
  • Publication number: 20090166913
    Abstract: A method of manufacturing a catheter shaft includes the steps of forming an inner layer of a first polymeric material, forming a plait matrix layer including a second polymeric material about the inner layer, and forming an outer layer of a third polymeric material about the plait matrix layer. The plait matrix layer includes a braided wire mesh partially or fully embedded within the second polymeric material, which is different from at least one of the first polymeric material forming the inner layer and the third polymeric material forming the outer layer. The second polymeric material has a higher yield strain and/or a lower hardness than at least the first polymeric material, and preferably both the first and the third polymeric materials. The first polymeric material and the third polymeric material may be different or the same. The catheter shaft may be formed by stepwise extrusion, co-extrusion, and/or reflow processes.
    Type: Application
    Filed: December 30, 2007
    Publication date: July 2, 2009
    Inventors: Xiaoping Guo, Richard E. Stehr
  • Publication number: 20090043285
    Abstract: The present invention is a splitable/peelable reinforced flexible tubular body (10) for a catheter or sheath (12). The body (10) comprises a proximal end (14), a distal end (16), a wall structure (18), and a lumen (20) defined by the wall structure (18). The wall structure (18) extends between the ends and includes a reinforcement layer (22) within the wall structure (18) and a separation line (26) extending longitudinally along the wall structure (18). The separation line (26) is adapted to facilitate the splitting/peeling of the wall structure (18) to allow a medical device such as a pacemaker lead to be removed from within the tubular body (10).
    Type: Application
    Filed: June 14, 2005
    Publication date: February 12, 2009
    Inventors: Richard E. Stehr, Xiaoping Guo
  • Publication number: 20080208128
    Abstract: A splittable/peelable tubular body (2) of a catheter or sheath wherein the tubular body (2) has a splittable/peelable atraumatic tip (14) is disclosed. The atraumatic tip (4) is generally softer than the tubular body (2). The tubular body (2) and atraumatic tip (4) each comprise a peel mechanism longitudinally extending along their respective lengths. The peel mechanisms are formed by longitudinally extending regions of interfacial bonding (11) between first and second longitudinally extending strips (8, 10) of polymer material. Each strip (8, 10) forms at least a portion of an outer circumferential surface of the tubular body (2) and atraumatic tip (4). A region of stress concentration extends along the region of interfacial bonding. The stress concentration facilitates the splitting of the tubular body (2) and atraumatic tip (4) along their respective peel mechanisms.
    Type: Application
    Filed: April 28, 2006
    Publication date: August 28, 2008
    Inventors: Xiaoping Guo, Richard E. Stehr, Vitaliy G. Epshteyn, Bruce P. Holman, Donald A. Sauter, Chad A. Thorstenson, Daniel J. Potter, Nalin S. Perera
  • Publication number: 20080161791
    Abstract: An ablation catheter is provided for ablating internal tissue of a patient. The catheter includes a distal end that is adapted to be inserted into a body cavity relative to a desired location therein (e.g., within the heart). An ablation electrode is connected relative to the distal end of the catheter for providing ablation energy to patient tissue. A heat sink is provided that is in thermal contact with the ablation electrode. The heat sink, in addition to being in thermal contact with the ablation electrode, is electrically isolated from the ablation electrode. This allows the heat sink to conduct heat away from the ablation electrode without dissipating electrical energy from the electrode. In this regard, the heat sink may prevent build-up of excess heat within the electrode that may result in blood coagulation and/or tissue charring.
    Type: Application
    Filed: December 29, 2006
    Publication date: July 3, 2008
    Inventors: Hong Cao, Xiaoping Guo, Isaac Shai, Michael Yang, Kedar Ravindra Belhe, Saurav Paul, Chou Thao
  • Publication number: 20080154206
    Abstract: A body (2) for a catheter or sheath is disclosed. The body (2) includes strips (8, 10) formed longitudinally from the proximal (6) portion of the body (2) to the distal (4) portion of the body (2). The strips are formed of different materials. The strips can have different radiopacities, or can be splittable/peelable. The splittable/peelable body comprises a peel mechanism longitudinally extending along its respective length. The peel mechanism can be formed by longitudinally extending regions of interfacial bonding between first and second longitudinally extending strips of polymer material. A region of stress concentration extends along the region of interfacial bonding. The stress concentration facilitates the splitting of the body (2) along its peel mechanism. The polymer material of the first strip (8) can have a greater amount of radiopaque filler than the polymer material of the second strip (10). Each strip forms at least a portion of an outer circumferential surface of the body (2).
    Type: Application
    Filed: April 28, 2006
    Publication date: June 26, 2008
    Inventors: Xiaoping Guo, Richard E. Stehr
  • Publication number: 20070254000
    Abstract: The invention comprises self-lubricating polymer compositions that are especially useful in medical devices and valves and gaskets of medical devices. In a preferred embodiment, the polymer compositions comprise a thermosetting or thermoplastic silicone elastomer in combination with a lubricity enhancing polyfluoropolyether fluid or hydrocarbon-based synthetic oil. In other preferred embodiments, the polymer compositions contain only biocompatible components. The improved anti-friction properties of the self-lubricating polymers can be demonstrated over a course of insertion and withdrawal cycles, where conventional polymers have changing and mostly increasing force required for each insertion and withdrawal, while the polymer compositions of the invention remain stable.
    Type: Application
    Filed: July 10, 2006
    Publication date: November 1, 2007
    Inventors: Xiaoping Guo, Richard E. Stehr
  • Patent number: 7081106
    Abstract: A hemostasis cannula unit including a valve housing, a cap, and a hemostasis valve, wherein the hemostasis valve includes a valve gasket and a valve membrane compressed against the valve gasket by the valve housing, wherein the valve gasket is thicker than the valve membrane.
    Type: Grant
    Filed: April 17, 2003
    Date of Patent: July 25, 2006
    Assignee: St. Jude Medical, Atrial Fibrillation Division, Inc.
    Inventors: Xiaoping Guo, Richard Stehr
  • Publication number: 20060151923
    Abstract: The present invention is a method of manufacturing a flexible tubular body for catheter, sheath or similar medical device. The method comprises pre-extruding an inner layer of the body from a thermoplastic polymer and then pulling the inner layer over a mandrel and tightening the layer down. If wire lumens were not integrally formed in the inner layer when pre-extruded, then two polymer spaghetti tubes, each with wire lumens, are laid 180 degrees apart axially along the outer surface of the inner layer. Deflection wires are then fed into the wire lumens. A cylindrical wire braid is woven or pulled over the inner layer (and the spaghetti tubes, as the case may be) and tightened down. The aforementioned components are then encased in an outer polymer layer. A heat-shrinkable tube is then placed over the outer layer.
    Type: Application
    Filed: January 10, 2005
    Publication date: July 13, 2006
    Inventors: Eric Wilkowske, Allan Fuentes, Xiaoping Guo, Xuan Khieu, Linda Nemec, Richard Stehr
  • Patent number: 6632200
    Abstract: A hemostasis cannula unit including a valve housing, a cap, and a hemostasis valve, wherein the hemostasis valve includes a proximal valve gasket and a distal valve gasket compressed against the valve gasket by the valve housing, wherein the proximal valve gasket is the same shape as the distal valve gasket.
    Type: Grant
    Filed: December 11, 2000
    Date of Patent: October 14, 2003
    Assignee: St. Jude Medical, Daig Division
    Inventors: Xiaoping Guo, Richard Stehr, Daniel J. Potter
  • Patent number: 6551283
    Abstract: A hemostasis cannula unit including a valve housing, a cap, and a hemostasis valve, wherein the hemostasis valve includes a valve gasket and a valve membrane compressed against the valve gasket by the valve housing, wherein the valve gasket is thicker than the valve membrane.
    Type: Grant
    Filed: January 25, 2000
    Date of Patent: April 22, 2003
    Assignee: St. Jude Medical, Daig Division
    Inventors: Xiaoping Guo, Richard Stehr
  • Publication number: 20020010425
    Abstract: A hemostasis cannula unit including a valve housing, a cap, and a hemostasis valve, wherein the hemostasis valve includes a proximal valve gasket and a distal valve gasket compressed against the valve gasket by the valve housing, wherein the proximal valve gasket is the same shape as the distal valve gasket.
    Type: Application
    Filed: December 11, 2000
    Publication date: January 24, 2002
    Applicant: Daig Corporation
    Inventors: Xiaoping Guo, Richard Stehr, Daniel J. Potter