Apparatus for widening a stenosis in a body cavity

• US 5,540,713 A
• Filed: 07/08/1994
• Issued: 07/30/1996
• Est. Priority Date: 10/11/1991
• Status: Expired due to Fees

• Current Assignee: Angiomed GmbH & Co. Medizintechnik KG
• Original Assignee: Angiomed AG (Becton, Dickinson & Co)
• Inventors: Lindenberg, Josef, Schnepp-Pesch, Wolfram
• Primary Examiner(s): Maglione, Corrine M.
• Assistant Examiner(s): GRING, NOELLE K
• Application Number:
  US08/272,046
• Time in Patent Office: 753 Days
• Field of Search: 606/198, 606/200, 623/1, 623/11, 623/12, 604/8, 604/96, 604/281
• US Class Current: 623/1.18
• CPC Class Codes: A61F 2/82 Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents stent-grafts for tubular structures of the body other than blood vessels A61F2/04; stent-grafts for blood vessels A61F2/07; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95; for closing wounds, or holding wounds closed A61B17/04 - A61B17/115; dilators A61M29/00
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/885 comprising a coil including a plurality of spiral or helical sections with alternate directions around a central axis
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/92 Stents in the form of a rolled-up sheet expanding after insertion into the vessel , e.g. with a spiral shape in cross-section
• CPC Class Codes: A61F 2210/0019 operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61M 29/02 Dilators made of swellable material balloon catheters for angioplasty A61M25/104

Abstract

An apparatus for widening a stenosis in a body cavity, such as an artery, in the bile duct, in the ureter, etc. is proposed, which in view of a problem-free, reliable and permanent widening of a stenosis is characterized by a memory alloy part having a cylindrical jacket-shaped outer contour, said part radially widening at a transition temperature, which is above ambient temperature, but below body temperature, while maintaining a cylindrical outer contour and at a temperature below the transition temperature the diameter is smaller than that of the vessel.

Claims

1. An apparatus for widening a stenosis in a body cavity, such as in an artery, a bile duct, a ureter or the like, said apparatus comprising a memory alloy part made from a shape memory alloy and having a substantially cylindrical jacket-shaped outer contour, said memory alloy part widening radially to a radially erect contour while maintaining a cylindrical outer contour on heating said memory alloy part to above a transition temperature which is above the ambient temperature, but below the body temperature, a diameter of the cylindrical outer contour at a temperature below the transition temperature being smaller than the diameter of the body cavity, wherein said memory alloy part comprises a flat sheet metal part which is cylindrically bent to form the cylindrical jacket-shaped outer contour with the memory alloy part having, at a temperature below the transition temperature, parallel elongated slots separated by webs with adjacent parallel slots being displaced longitudinally from one another such that, on heating said memory alloy part to above the transition temperature, the cylindrically bent part is made radially erect by formation of diamond-shaped gaps between the webs by the widening of said slots.

2. An apparatus according to claim 1, wherein said memory alloy part is embedded in a closed jacket of tissue-compatible material.

3. An apparatus according to claim 2, wherein:

the memory alloy is a nickel-titanium alloy.

4. An apparatus according to claim 3 wherein:

the transition temperature is between 30°

C. and 35°

C.

5. An apparatus according to claim 4 wherein:

the transition temperature is 35°

C.

6. An apparatus according to claim 2 wherein:

the transition temperature is between 30°

C. and 35°

C.

7. An apparatus according to claim 6 wherein:

the transition temperature is 35°

C.

8. An apparatus according to claim 1, wherein:

the memory alloy is a nickel-titanium alloy.

9. An apparatus according to claim 8 wherein:

the transition temperature is between 30°

C. and 35°

C.

10. An apparatus according to claim 9 wherein:

the transition temperature is 35°

C.

11. An apparatus according to claim 1 wherein:

the transition temperature is between 30°

C. and 35°

C.

12. An apparatus according to claim 11 wherein:

the transition temperature is 35°

C.