Anti-Pulmonary embolism filter

• US 5,531,788 A
• Filed: 05/02/1994
• Issued: 07/02/1996
• Est. Priority Date: 10/09/1989
• Status: Expired due to Fees

• Current Assignee: Association Pour La Recherche EN Imagerie de L'Hopital Antoine Beclere, Foundation Pour L'Avenir Pour La Recherche Medicale Appliquee
• Original Assignee: Association Pour La Recherche EN Imagerie de L'Hopital Antoine Beclere, Foundation Pour L'Avenir Pour La Recherche Medicale Appliquee
• Inventors: Musset, Dominique, Dibie, Alain
• Primary Examiner(s): BRITTINGHAM, DEBRA
• Application Number:
  US08/239,831
• Time in Patent Office: 792 Days
• Field of Search: 623/1, 623/4, 128/833, 128/DIG. 22, 606/194, 606/200, 606/157, 606/158
• US Class Current: 623/11.11
• CPC Class Codes: A61B 90/39 Markers, e.g. radio-opaque or breast lesions markers
• CPC Class Codes: A61F 2/01 Filters implantable into blood vessels
• CPC Class Codes: A61F 2/011 Instruments for their placement or removal
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61F 2230/0006 circular
• CPC Class Codes: A61F 2250/0098 radio-opaque, e.g. radio-opaque markers

Abstract

The present invention relates to an anti-pulmonary embolism filter of the pe made of a remanent spring effect resilient wire, characterized in that it is shaped into a spiral (1) having three non-touching turns (2, 3, 4) with the middle turn (3) having a diameter (d3) greater than the diameters (d2, d4) of the other two turns, and in that this diameter (d3) is selected to be close to the half-circumference of the vena cava in the zone where the filter is to be implanted so as to ensure that the function of holding the filter in place by flattening of the vena cava is optimized.

Claims

1. An anti-embolism filter for implanting in a vena cava comprising a rectilinear resilient wire having a remanent spring effect shaped into a spiral structure comprising three substantially circular non-touching coaxial turns formed of a middle turn and two lateral turns, with the two lateral turns having at least substantially equal diameters, while the middle turn has a diameter greater than the diameter of each of the two lateral turns, said diameter of the middle turn being greater than 16 mm so as to be about one-half a circumference of the vena cava in a zone where the filter is to be implanted in order to ensure that the filter is optimally held in place by flattening of the vena cava when said filter is implanted in said vena cava with its axis perpendicular to the axis of said vena cava, wherein each of a proximal end and a distal end of the filter are provided with a radio-opaque element and, when implanted in the vena cava, the filter retains any clot migrating with the blood before said clot penetrates into the heart to avoid pulmonary embolism while allowing free flowing of the fluid blood in the vena cava.

2. An anti-embolism filter for implanting in a vena cava comprising a rectilinear resilient metal wire having a remanent spring effect shaped into a spiral structure comprising three substantially circular non-touching coaxial turns formed of a middle turn and two lateral turns, with the two lateral turns having at least substantially equal diameters, while the middle turn has a diameter greater than 16 mm and greater than 1.4 times the diameter of each of the two lateral turns, so that said diameter of the middle turn is about one-half a circumference of the vena cava in a zone where the filter is to be implanted with its axis perpendicular to the axis of said vena cava in order to ensure that the filter is optimally held in place by flattening of the vena cava, wherein, when implanted in the vena cava, the filter retains any clot migrating with the blood before said clot penetrates into the heart to avoid pulmonary embolisms while allowing free flowing of the fluid blood in the vena cava, and wherein the pitches of the three turns are substantially equal and each of a proximal end and a distal end of the filter are provided with a radio-opaque element.

3. An anti-embolism filter for implanting in a vena cava comprising a rectilinear resilient wire having a remanent spring effect shaped into a spiral structure comprising three substantially circular non-touching turns with a middle turn adjacent two end and having a diameter greater than a diameter of each of the two end turns, said diameter of the middle turn being greater than 16 mm so as to be about one-half of the vena cava circumference where the filter is to be implanted with its axis perpendicular to the axis of said vena cava in order to ensure that the filter is optimally held in place by flattening of the vena cava, wherein, when implanted in the vena cava, the filter retains any clot migrating with the blood before said clot penetrates into the heart to avoid pulmonary embolism while allowing free flowing of the fluid blood in the vena cava.

4. An anti-pulmonary embolism filter according to claim 3, characterized in that the filter has a proximal end provided with a radio-opaque ovoid element.

5. An anti-pulmonary embolism filter according to claim 3, characterized in that the filter has a distal end provided with a radio-opaque cylinder having a rounded free end.

6. An anti-pulmonary embolism filter according to claim 3, characterized in that it is made of metal.

7. An anti-pulmonary embolism filter according to claim 6, characterized in that it is made from an alloy selected from the group consisting of:

1) copper, nickel, and aluminum;

     2) copper, zinc, and aluminum;

     3) copper, zinc, aluminum, and nickel; and

     4) copper, tin, and nickel.

8. An anti-pulmonary embolism filter according to claim 3, characterized in that the wire of the filter and its ends are covered overall with a thin layer of gold.

9. An anti-pulmonary embolism filter according to claim 3, characterized in that the two end turns are of substantially equal diameters.

10. An anti-pulmonary embolism filter according to claim 3, characterized in that the three turns are substantially coaxial.

11. An anti-pulmonary embolism filter according to claim 3, characterized in that wire has a diameter of 0.25 mm to 1 mm.

12. An anti-pulmonary embolism filter according to claim 11, characterized in that the filter has a diameter of 0.37 mm.

13. An anti-pulmonary embolism filter according to claim 3, characterized in that the filter has a total length of about 22 cm to 35 cm.

14. An anti-pulmonary embolism filter according to claim 3, characterized in that the diameter of the middle turn is at least 1.25 times the diameters of the end turns.

15. An anti-pulmonary embolism filter according to claim 3, characterized in that the diameter of the middle turn is at least 1.4 times the diameters of the end turns.

16. An anti-pulmonary embolism filter according to claim 3, characterized in that the three turns have substantially equal pitches.

17. An anti-pulmonary embolism filter according to claim 3, characterized in that the spiral, when at rest and prior to implantation, has a pitch of not less than 3 mm.

18. An anti-pulmonary embolism filter according to claim 3, characterized in that the filter, at rest prior to implantation, has an axial extent of at least 9 mm.

19. An anti-pulmonary embolism filter according to claim 3, characterized in that the diameter of the middle turn is at least 2 times the filter'"'"'s axial extent when at rest prior to being implanted.

20. An anti-pulmonary embolism filter according to claim 4, characterized in that the ovoid element provided at the proximal end of the filter has a maximum diameter of about 1.3 mm and a maximum length of about 3.5 mm.

21. An anti-pulmonary embolism filter according to claim 5, characterized in that the radio-opaque cylinder has a diameter of about 0.6 mm and a length of about 4 mm.

22. An anti-embolism filter for implanting in a vena cava comprising a rectilinear resilient metal wire having a remanent spring effect shaped into a spiral structure comprising three substantially circular, non-touching coaxial turns in form of a middle turn and two lateral turns, with the two lateral turns having at least substantially equal diameters, while the middle turn has a diameter greater than 1.4 times the diameter of each of the two lateral turns, said diameter of the middle turn being greater than 16 mm so as to be about one-half the circumference of the vena cava in a zone where the filter is to be implanted with its axis perpendicular to the axis of said vena cava in order to ensure that the filter is optimally held in place by flattening of the vena cava, wherein the pitch of the three turns are substantially equal, the axial extent of the filter at rest prior to implantation is at least 9 mm, the diameter of the middle turn is greater than 2 times the axial extent at rest of the filter prior to being implanted and a proximal end and a distal end of the filter are provided with a rounded radio-opaque element, and wherein, when implemented in the vena cava, the filter retains so as to retain any clot migrating with the blood before said clot penetrates into the heart, to avoid pulmonary embolism, while allowing free flowing of the fluid blood in the vena cava.

23. An anti-embolism filter for implanting into the vena cava consisting of a rectilinear resilient wire having a remanent spring effect shaped into a spiral structure comprising three substantially circular non-touching coaxial turns with a middle turn adjacent two end turns and having a diameter greater than the diameter of each of the two end turns, said diameter of the middle turn being 27-36 mm so as to be about one-half of the vena cava circumference where the filter is to be implanted with its axis perpendicular to the axis of said vena cava in order to ensure that the filter is optimally held in place by flattening of the vena cava.

24. An anti-embolism filter for implanting into the vena cava consisting of a rectilinear resilient wire having a remanent spring effect shaped into a spiral structure consisting of three substantially circular non-touching coaxial turns with a middle turn adjacent two end turns and having a diameter greater than the diameter of each of the two end turns and greater than 16 mm, so as to be about one-half of the vena cava circumference where the filter is to be implanted with its axis perpendicular to the axis of said vena cava in order to ensure that the filter is optimally held in place by flattening of the vena cava.

25. An anti-embolism filter for implanting into a vena cava comprising a rectilinear resilient single wire having a remanent spring effect shaped into a spiral structure comprising three substantially circular non-touching coaxial consecutive turns with a middle turn adjacent two end turns and having a diameter greater than the diameter of each of the two end turns, said diameter of the middle turn being 27-36 mm so as to be about one-half of the vena cava circumference where the filter is to be implanted with its axis perpendicular to the axis of said vena cava in order to ensure that the filter is optimally held in place by flattening of the vena cava, wherein, when implanted in the vena cava, the filter retains any clot migrating with the blood before said clot penetrates into the heart to avoid pulmonary embolism while allowing free flowing of the fluid blood in the vena cava.

26. An anti-embolism filter for implanting into a vena cava comprising a rectilinear resilient single wire having a remanent spring effect shaped into a spiral structure consisting of three substantially circular non-touching coaxial consecutive turns with a middle turn adjacent to two end and having a diameter greater than the diameter of each of the two end turns and greater than 16 mm, so as to be about one-half of the vena cava circumference where the filter is to be implanted with its axis perpendicular to the axis of said vena cava in order to ensure that the filter is optimally held in place by flattening of the vena cava, wherein, when implanted in the vena cava, the filter retains any clot migrating with the blood before said clot penetrates into the heart to avoid pulmonary embolism while allowing free flowing of the fluid blood in the vena cava.

27. An anti-embolism filter for implanting into the vena cava made of a rectilinear resilient wire having a remanent spring effect shaped into a spiral structure comprising a non-planar spiral having two lateral turns connected by a middle turn having a diameter greater than the diameter of each of the lateral turns and greater than 16 mm, in order to assure that, when the filter is implanted in the vena cava with its axis perpendicular to the axis of said vena cava, the filter flattens the vena cava and is optimally held in place so as to retain any clot migrating with the blood before said clot penetrates in the heart to avoid pulmonary embolism while allowing free flowing of the fluid blood.