Classifications

• • A—HUMAN NECESSITIES
  • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
  • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
  • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
  • A61F2/02—Prostheses implantable into the body
  • A61F2/04—Hollow or tubular parts of organs, e.g. bladders, tracheae, bronchi or bile ducts
  • A61F2/06—Blood vessels
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
  • F16L11/00—Hoses, i.e. flexible pipes
  • F16L11/04—Hoses, i.e. flexible pipes made of rubber or flexible plastics
  • F16L11/11—Hoses, i.e. flexible pipes made of rubber or flexible plastics with corrugated wall
  • F16L11/118—Hoses, i.e. flexible pipes made of rubber or flexible plastics with corrugated wall having arrangements for particular purposes, e.g. electrically conducting

Definitions

• vascular prosthesis and particularly a prosthesis in the form of a tube of textile material to be used for. replacing a portion of a blood vessel in a human or animal body.
• Vascular prostheses are well known and are customarily constructed of knitted tubes formed with circumferential corrugations.
• the corrugations are provided for two reasons, one to allow the prosthesis to be extended in length during fitting and the other
• a vascular prosthesis according to the invention comprises a tube of textile material formed with corrugations in the form of a primary helix and is characterized in that secondary corrugations in the form of a secondary helix of opposite and greater pitch than the primary helix are superposed on the corrugations of the primary helix.
• one helix is of left hand or S pitch and the other helix is of right hand or Z pitch.
• the tube of textile material may be formed by warp knitting, by weaving or by braiding and is preferably seamless.
• a prosthesis according to the invention may be formed by winding a thread in one direction around the tube while it is held on a rigid former to delineate the primary helix then winding another thread around the tube in the opposite direction and with a greater pitch to delineate the secondary helix then applying axial pressure in opposite directions from the two ends whereby to reduce the length of the tube and cause the portions of the tube between the thread convolutions to bulge outwardly and form the corrugations and while the tube is held in this position heat-treating the material to set the tube material and cause the corrugations to be permanent.
• FIG. 1 denotes a tube of textile material
• 2 denotes a primary helix
• 3 denotes a secondary helix superposed on the primary helix 2.
• the dimensions of a typical prosthesis according to the invention are: minimum internal diameter - 10 mm, pitch of primary helix - 10 turns/cm, pitch of secondary helix — 2 turns/cm, depth of corrugations - O. ⁇ mm.
• the corrugation depth given provides the required degree of stiffness and resistance to buckling and collapse in a prosthesis of the minimum diameter.
• a known prosthesis of the same minimum diameter having a single set of corrugations would have required corrugations of at least 1.2 mm depth with a pitch of about 7 turns/cm. t .
• the invention having two sets of contra-pitch corrugations of low amplitude presents much less impedence to blood flow through the tube and also a greater evenness in build up of fibrous tissue than a known vascular prosthesis of the same degree of
• grafts having a"single set of corrugations of high amplitude.
• a prosthesis according to the invention formed with corrugations of the same amplitude as a known vascular prosthesis has a greater degree of stiffness and resistance to buckling and

Landscapes

• Health & Medical Sciences (AREA)
• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Heart & Thoracic Surgery (AREA)
• Life Sciences & Earth Sciences (AREA)
• Transplantation (AREA)
• Cardiology (AREA)
• Biomedical Technology (AREA)
• Pulmonology (AREA)
• Vascular Medicine (AREA)
• Oral & Maxillofacial Surgery (AREA)
• Animal Behavior & Ethology (AREA)
• General Health & Medical Sciences (AREA)
• Public Health (AREA)
• Veterinary Medicine (AREA)
• Gastroenterology & Hepatology (AREA)
• Mechanical Engineering (AREA)
• Prostheses (AREA)

Priority Applications (2)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10529291

Family Applications (1)

Country Status (7)

Cited By (13)

Families Citing this family (1)

Citations (4)

• 1983
  • 1983-03-22 GR GR70855A patent/GR77133B/el unknown
  • 1983-03-24 ES ES520934A patent/ES8403312A1/es not_active Expired
  • 1983-03-24 WO PCT/GB1983/000090 patent/WO1983003349A1/en not_active Application Discontinuation
  • 1983-03-24 EP EP83900955A patent/EP0104199A1/en not_active Withdrawn
  • 1983-03-24 JP JP58501095A patent/JPS6038135B2/ja not_active Expired
  • 1983-03-25 IT IT8347996A patent/IT8347996A0/it unknown
  • 1983-11-21 DK DK5319/83A patent/DK531983D0/da not_active Application Discontinuation
  • 1983-12-01 ES ES1983284568U patent/ES284568Y/es not_active Expired

Patent Citations (4)

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