Percutaneous anti-migration vena cava filter

• US 5,059,205 A
• Filed: 09/07/1989
• Issued: 10/22/1991
• Est. Priority Date: 09/07/1989
• Status: Expired due to Term

• Current Assignee: Lifescreen Sciences LLC (Acacia Research Corporation)
• Original Assignee: Boston Scientific Corporation
• Inventors: Sahatjian, Ronald A., El-Nounou, Fozan O., Kordis, Thomas F., Weinreich, Michael, Savin, Michael A.
• Primary Examiner(s): Rosenbaum, C. Fred
• Assistant Examiner(s): Lewis, William W.
• Application Number:
  US07/404,166
• Time in Patent Office: 775 Days
• Field of Search: 606/198, 606/200, 606/195, 128/899, 210/448
• US Class Current: 606/200
• CPC Class Codes: A61F 2/0105 Open ended, i.e. legs gathered only at one side
• CPC Class Codes: A61F 2002/016 made from wire-like elements
• CPC Class Codes: A61F 2002/8486 provided on at least one of the ends
• CPC Class Codes: A61F 2230/005 Rosette-shaped, e.g. star-shaped
• CPC Class Codes: A61F 2230/0067 conical

Abstract

A filter device positionable within a blood vessel for trapping blood clots in that vessel, the filter device comprising a head with a plurality of divergent legs each secured at its proximal end, to the head, each leg having a hook arranged at its distal end. The distal end includes a reversely bent portion of the leg which itself is bent radially outwardly, ending in the shape of a sharp point. The reversely bent portion of the leg comprises a pad to minimize the depth of penetration of the hook.

A further embodiment of the leg shows a radially outwardly directed radius of curvature to create a conical configuration to the filter assembly, while distributing the stress concentration along the length of the bend, so that the elastic limit of the material, stainless steel in this embodiment, is not exceeded, and which permits compact delivery of the filter, and adequate radially directed force to permit slight hook penetration of a vessel wall.

Claims

1. A filter device positionable within a blood vessel, for trapping blood clots, comprising:

an apical head;

a plurality of divergent legs each secured at one of its ends to said head and each having securement means on its distal end with respect to said head;

said securement means comprising a distalmost portion of each leg having a further leg segment thereadjacent, said further leg segment also defining a hook arranged outwardly from said leg and proximal to said further leg segment, the distal portion of each leg and said further leg segment comprising a pad to prevent extensive penetration of said hook through a wall of a blood vessel;

said pad being comprised of a reverse bend in said distalmost portion of said leg, to provide parallel leg segments thereadjacent.

2. A filter device as recited in claim 1, wherein said hook is disposed from said further leg segment at an angle of about 70°

to about 90°

with respect to said divergent leg.

3. A filter device as recited in claim 1, wherein said divergent legs define a generally conically shaped geometric configuration, having a longitudinally directed centerline therethrough including said apical head, wherein said pads extend radially further from said longitudinal centerline than do said hooks.