Patents Assigned to Impra, Inc.
-
Patent number: 6589278Abstract: A vascular prosthesis (50) comprises a tube (52) of material other than autologous vascular tissue, the tube having an end formation for surgical connection direct to an opening formed in an artery, the formation comprising an enlarged chamber (54) having a heel (56) and a toe (58) at opposite ends of a first longer diameter parallel to the axis of the tube and a second shorter transverse diameter the enlarged chamber serving to promote localised movement of blood having a non-laminar nature with a shear stress inducing relationship to receiving arterial wall.Type: GrantFiled: October 5, 2001Date of Patent: July 8, 2003Assignee: IMPRA, Inc.Inventors: Peter Lyon Harris, Thien Voon How
-
Patent number: 6589273Abstract: A delivery system and device for re-lining bodily vessels. A stent is attached to a distal end of a tubular lining made of biocompatible material and loaded into a hollow atraumatic tip. A semi-rigid shaft connects the atraumatic tip to a stopper and runs through the center of the tubular lining. The proximal end of the tubular lining is attached to a sliding hub. Optionally, a balloon is positioned near the stent in fluid communication with the shaft. The assembled device is introduced into a bodily vessel following an endarterectomy or atherectomy procedure. The atraumatic tip is delivered to a predetermined location and upon reaching that destination, the stent is released from the tip to expand against the vessel wall. If a balloon is utilized, it is inflated to ensure that the stent is fully deployed within the vessel. The balloon is then deflated arid the tip and shaft are pulled through the expanded stent and tubular lining.Type: GrantFiled: October 2, 2000Date of Patent: July 8, 2003Assignee: Impra, Inc.Inventor: John D. McDermott
-
Patent number: 6558414Abstract: Partially encapsulated stents are made using strips and bands of covering material. In one embodiment ringed stents are placed over an inner ePTFE tube (e.g., supported on a mandrel) and are covered by a series of longitudinal strips. A series of spaced apart ePTFE circumferential bands can then be placed over the top of the longitudinal strips and ringed stents; alternatively bands alone or strips alone may be employed. All of the components of the structure are then laminated to the inner ePTFE tube to capture the stent. By selecting the size and position of the ePTFE bands, it is possible to leave critical parts of the stent unencapsulated to facilitate flexibility and expansion. The longitudinal strips can be woven about the stent and later laminated into position to provide an anti-compression function as well as overall structural stability. Although a single stent can be used, these approaches lend themselves to use of a plurality of individual ring stents spaced apart along the inner ePTFE tube.Type: GrantFiled: September 29, 1999Date of Patent: May 6, 2003Assignee: Impra, Inc.Inventor: Richard Layne
-
Patent number: 6547814Abstract: A method for selectively bonding layers of polymeric material, especially expanded polytetrafluoroethylene (ePTFE), to create endoluminal vascular devices. In a preferred method the selective bonding is achieved by applying pressure to selected areas using a textured mandrel. This permits a stent device to be encapsulated between two layers of ePTFE with unbonded slip pockets to accommodate movement of the structural members of the stent. This allows stent compression with minimal force and promotes a low profile of the compressed device. Unbonded regions of ePTFE allow enhanced cellular penetration for rapid healing and can also contain bioactive substance that will diffuse through the ePTFE to treat the vessel wall.Type: GrantFiled: January 16, 2001Date of Patent: April 15, 2003Assignee: IMPRA, Inc.Inventors: Tarun J. Edwin, Scott L. Randall, Brendan J. McCrea, Christopher E. Banas
-
Patent number: 6514261Abstract: A delivery mechanism for an implantable stent which provides a high mechanical advantage to the surgeon and convenient operation so as to facilitate smooth withdrawal of an outer catheter sheath following placement of the stent in the desired location within the patient's vessel. Preferred embodiments include a moving rail actuated by a V-shaped lever, a hydraulic actuator, a rack and pinion drive, and a power screw system. The delivery mechanism has a movable member that is attached to the outer catheter sheath so that actuating the mechanism results in an incremental movement of the moveable member, which in turn results in an incremental movement of the outer catheter sheath. Once the outer catheter sheath is retracted from the stent, the stent is deployed into the patient's vessel and the remaining parts of the mechanism, including an inner tube, an atraumatic tip, and a stabilizing element, are easily removed.Type: GrantFiled: September 30, 1999Date of Patent: February 4, 2003Assignee: Impra, Inc.Inventors: Scott L. Randall, Brendan J. McCrea, Christopher J. Brooks, Donald Van Royen
-
Patent number: 6451047Abstract: Shape memory alloy and elastically self-expanding endoluminal stents which are at least partially encapsulated in a substantially monolithic expanded polytetrafluoroethylene (“ePTFE”) covering. An endoluminal stent, which has a reduced diametric dimension for endoluminal delivery and a larger in vivo final diametric diameter, is encapsulated in an ePTFE covering which circumferentially covers both the luminal and abluminal walls along at least a portion of the longitudinal extent of the endoluminal stent. The shape memory endoluminal stent is fabricated from a shape memory alloy which exhibits either shape memory or pseudoelastic properties or from an elastic material having an inherent spring tension.Type: GrantFiled: April 9, 1997Date of Patent: September 17, 2002Assignee: Impra, Inc.Inventors: Brendan J. McCrea, Tarun J. Edwin, Christopher E. Banas
-
Patent number: 6358276Abstract: An endoluminal stent contains a hollow passageway for the circulation of fluids to treat vascular walls affected with malignant growths or experiencing restenosis. The hollow passageway stent can have one or a plurality of passageways and is configured in a tubular shape with numerous coils, providing an empty tubular lumen through the center of the stent to allow blood flow. The stent is connected to a removable catheter that conducts fluid to the stent. Fluid flow may be regulated by valves incorporated in either the stent and/or the catheter. The stent and catheter are connected to avoid leakage of the fluid. Cryogenic, heated or radioactive fluids are circulated through the stent to treat the affected sites. A method of delivering drugs to the vascular wall is also provided by creating a stent with porous outer walls to allow diffusion of the drug.Type: GrantFiled: May 27, 1999Date of Patent: March 19, 2002Assignee: Impra, Inc.Inventor: Tarun J. Edwin
-
Patent number: 6355063Abstract: An improved ePTFE-based delivery graft is intended to dispense a bioactive agent such as a drug into the blood stream. A hollow tubing is infused with the agent from a source such as a drug delivery pump mechanism. The spiral hollow tubing is wrapped in a helical fashion around, or otherwise brought into contact with an outer wall of a porous ePTFE graft and adhered thereto. The agent is delivered to the lumen of the graft by infusing the agent through the porous interstices of the graft wall. Thus, the bioactive agent is conducted by the hollow tubing from a source to the outer surface of an ePTFE graft where it is released to diffuse into the graft to influence biological processes along both the inner and outer surfaces of the graft. The present invention allows the bioactive agent or drug to be renewed or changed after implant of the graft. In addition the present invention can be implanted in the same fashion as regular vascular grafts.Type: GrantFiled: January 20, 2000Date of Patent: March 12, 2002Assignee: Impra, Inc.Inventor: Robert W. Calcote
-
Patent number: 6312462Abstract: The device of the present invention comprises a bifurcated graft fabricated from expanded PTFE (ePTFE). The inventive device is double walled so that following insertion into an aneurysm, fluid can be injected between the walls to expand the device thereby opening the inner tubular graft for receiving blood flow and locking the device into place in the aorta. The injected fluid may polymerize so that the device is permanently held in its expanded form. One embodiment of the device is fabricated with pockets or channels. After the device is delivered and expanded additional stiffening struts can be inserted into these pockets. In this way the basic device can be furled and tightly compressed for delivery (something not possible with a stent containing device). After the device is expanded, a stent-like structure can be inserted endovascularly giving the strength and resiliency of a stent-containing prosthesis.Type: GrantFiled: September 22, 1999Date of Patent: November 6, 2001Assignee: Impra, Inc.Inventors: John D. McDermott, David Renzi, Richard W. Layne, Christopher E. Banas
-
Patent number: 6273912Abstract: An expanded polytetrafluoroethylene flanged vascular graft (10) suitable for end-to-side anastomosis grafting having an integral terminal polytetrafluoroethylene flanged skirt or cuff section (12) which facilitates an end-to-side anastomosis directly between an artery and the expanded polytetrafluoroethylene flanged bypass graft (10) without need for an intervening venous collar or venous patch.Type: GrantFiled: December 8, 1998Date of Patent: August 14, 2001Assignee: Impra, Inc.Inventors: Hans Scholz, Ulf Kruger, Utz Settmacher
-
Patent number: 6245099Abstract: A method for selectively bonding layers of polymeric material, especially expanded polytetrafluoroethylene (ePTFE), to create endoluminal vascular devices. In a preferred method the selective bonding is achieved by applying pressure to selected areas using a textured mandrel. This permits a stent device to be encapsulated between two layers of ePTFE with unbonded slip pockets to accommodate movement of the structural members of the stent. This allows stent compression with minimal force and promotes a low profile of the compressed device. Unbonded regions of ePTFE allow enhanced cellular penetration for rapid healing and can also contain bioactive substance that will diffuse through the ePTFE to treat the vessel wall.Type: GrantFiled: September 30, 1999Date of Patent: June 12, 2001Assignee: Impra, Inc.Inventors: Tarun J. Edwin, Scott L. Randall, Brendan J. McCrea, Christopher E. Banas
-
Patent number: 6221101Abstract: A vascular prosthesis comprising a tube of material other than autologous vascular tissue but considered/approved as safe and supple enough for use instead of such tissue, the tube having an end formation for surgical connection directly to an opening formed in an artery, the end formation serving to promote, at that end and/or within the direct connection and in response to normally pulsed blood flow, localized movement of blood having a non-laminar nature with a shear stress inducing relation to receiving arterial wall.Type: GrantFiled: October 30, 1998Date of Patent: April 24, 2001Assignee: IMPRA, Inc.Inventors: Peter Lyon Harris, Thien Voon How
-
Patent number: 6203735Abstract: A method of shaping three-dimensional products by manipulating an expanded polytetrafluoroethylene tubular body into a desired three-dimensional conformation. The present invention entails radially expanding a longitudinally expanded polytetrafluoroethylene (ePTFE) tube to form a radially expanded ePTFE (rePTFE) tube, engaging the rePTFE tube circumferentially about a shaping mandrel, heating the assembly to a temperature below the crystalline melt point temperature, or sintering temperature, of polytetrafluoroethylene to radially shrink the diameter of the rePTFE tube into intimate contact with the shaping mandrel, and heating the assembly to a temperature above the crystalline melt point temperature of polytetrafluoroethylene to amorphously lock the microstructure of the shaped polytetrafluoroethylene body.Type: GrantFiled: February 3, 1997Date of Patent: March 20, 2001Assignee: Impra, Inc.Inventors: Tarun J. Edwin, Scott Randall
-
Patent number: 6190590Abstract: A method and apparatus for forming a flanged polytetrafluoroethylene cuffed section from a tubular polytetrafluoroethylene graft. The flanged polytetrafluoroethylene graft is well suited for use as a distal bypass graft, for arteriovenous grafting, or as a hemodialysis access graft. The graft includes an integral terminal polytetrafluoroethylene flanged skirt or cuff section which facilitates an end-to-side anastomosis directly between an artery and the polytetrafluoroethylene flanged graft without need for an intervening venous collar or venous patch.Type: GrantFiled: August 27, 1998Date of Patent: February 20, 2001Assignee: Impra, Inc.Inventors: Scott Randall, Roy H. Tang, Albert L. Lamay
-
Patent number: 6124523Abstract: An encapsulated stent including a stent or structural support layer sandwiched between two biocompatible flexible layers. One preferred embodiment has a stent cover which includes a tubular shaped stent that is concentrically retained between two tubular shaped grafts of expanded polytetrafluoroethylene. Another preferred embodiment has a stent graft which includes at least one stent sandwiched between the ends of two tubular shaped grafts wherein at least a portion of the grafts are unsupported by the stent. Still another embodiment includes an articulating stented graft which includes a plurality of stents spaced apart from one another at a predetermined distance wherein each stent is contained between two elongated biocompatible tubular members. The graft/stent/graft assemblies all have inseparable layers.Type: GrantFiled: March 10, 1995Date of Patent: September 26, 2000Assignee: Impra, Inc.Inventors: Christopher E. Banas, Tarun J. Edwin
-
Patent number: 6053943Abstract: A structurally supported graft (10) having a support structure (26) with strain relief sections (30) contained with an internal surface, an external surface, or a wall thickness of a tubular graft member (12). The structurally supported graft (10) may include a beading element (24) which is co-extruded with the support structure (26) having strain relief sections (30) and spiraled about the tubular graft (10). The support structure (26) includes differing types of strain relief sections (30) which are capable of allowing for the longitudinal and radial expansion of the structurally supported graft (10), respectively. The strain relief sections (30) may also include unconnected ends which form outwardly protruding barbs (62) upon expansion of the structurally supported graft within a blood vessel or body lumen.Type: GrantFiled: May 28, 1998Date of Patent: April 25, 2000Assignee: Impra, Inc.Inventors: Tarun J. Edwin, Christopher E. Banas
-
Patent number: 6004348Abstract: An radially expandable stent-graft and method of making the same, including at least one a stent member encapsulated between at least two longitudinally expanded polytetrafluoroethylene (ePTFE) coverings. The at least one stent member has openings through wall surfaces of the stent to permit radial expansion. The at least two longitudinally expanded ePTFE coverings are circumferentially applied over the at least one stent member in their unsintered state, and sintered during application of a circumferential pressure to bond the ePTFE around and through the wall surfaces of the stent. The sintered ePTFE forms a substantially continuous, monolithic and integral encapsulation of the at least one stent. Upon radial expansion of the stent-graft, the stent and the ePTFE node-fibril microstructure radially deform. Radial deformation of the ePTFE encapsulation results in nodal elongation in the axis of radial expansion.Type: GrantFiled: April 27, 1998Date of Patent: December 21, 1999Assignee: Impra, Inc.Inventors: Christopher E. Banas, Tarun J. Edwin, David Dalessandro
-
Patent number: 5935667Abstract: A dual porosity PTFE tube including an inner surface of expanded PTFE material having a first porosity and an outer surface of expanded PTFE material having a porosity different from that of the inner surface. The preferred method includes the step of forming inner and outer preformed tubular billets of PTFE resin particles mixed with a lubricant; the outer billet is adapted to closely fit around and concentric to the inner billet. Porosity of the inner and outer surfaces is varied by changing, in the respective billets, the lubrication level and/or the PTFE resin characteristic average particle size. The inner billet is placed inside the outer billet, and the two are extruded together, thereby melding the two billets. The extrudate is then longitudinally expanded and sintered. The inner surface of the resulting PTFE tube exhibits a different porosity than the outer surface of the tube; the porosities of the inner and outer surfaces are both within a range of about 0.10-200 .mu..Type: GrantFiled: June 10, 1997Date of Patent: August 10, 1999Assignee: Impra, Inc.Inventors: Robert Calcote, Rajagopal R. Kowligi, Stacy Wollner
-
Patent number: 5827327Abstract: A carbon containing vascular graft formed of expanded polytetrafluoroethylene and activated carbon admixed with at least a portion of the expanded polytetrafluoroethylene. A bioactive substance may be incorporated in the carbon containing vascular graft.Type: GrantFiled: January 3, 1997Date of Patent: October 27, 1998Assignee: IMPRA, Inc.Inventors: James M. McHaney, Christopher E. Banas
-
Patent number: D459474Type: GrantFiled: June 19, 2001Date of Patent: June 25, 2002Assignee: IMPRA, Inc.Inventors: Bill Bratt, Christopher J. Brooks, Donald F. Van Royen, Walter R Stoeckmann