Cardiovascular prosthetic devices and implants with porous systems

• US 4,374,669 A
• Filed: 11/19/1979
• Issued: 02/22/1983
• Est. Priority Date: 05/09/1975
• Status: Expired due to Term

• Current Assignee: Pacesetter Incorporated (Abbott Laboratories)
• Original Assignee: David C Mac Gregor
• Inventors: Mac Gregor, David C.
• Primary Examiner(s): Silverberg, Sam
• Application Number:
  US06/095,151
• Time in Patent Office: 1,191 Days
• Field of Search: 3/1.9, 3/1, 3/1.5, 3/1.4, 75/222, 75/208 R
• US Class Current: 419/9
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence
• CPC Class Codes: A61F 2/06 Blood vessels
• CPC Class Codes: A61L 27/14 Macromolecular materials
• CPC Class Codes: A61L 27/18 obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: A61L 27/34 Macromolecular materials
• CPC Class Codes: A61L 27/56 Porous materials, e.g. foams or sponges
• CPC Class Codes: A61L 33/022 Metal or alloys
• CPC Class Codes: A61N 1/05 for implantation or insertion into the body, e.g. heart electrode A61N1/06 takes precedence
• CPC Class Codes: A61N 1/0565 Electrode heads
• CPC Class Codes: C08L 75/00 Compositions of polyureas or polyurethanes; Compositions of derivatives of such polymers
• CPC Class Codes: Y10T 428/12042 Porous component

Abstract

Novel cardiovascular prosthetic devices or implants having many useful cardiovascular applications comprise a porous surface and a network of interconnected interstitial pores below the surface in fluid flow communication with the surface pores. Tissue forms a smooth thin adherent coating of self-determining thickness on the porous surface making it resistant to the formation of the blood clots normally associated with the presence of foreign bodies in the blood stream. The device has particular utility in heart valves, pacemaker electrodes, blood pumps, blood stream filters, an artificial pancreas, vascular access tubes, small and large bore vascular grafts, blood pump diaphragms and vascular and intracardiac patches.

Claims

1. A method of formation of a composite structure in cardiovascular devices or implants constructed of rigid metal inert to blood to inhibit the incidence of thrombo-embolism and consisting of a rigid coherent metal substrate and a porous coating formed on and adhered to blood-engaging surfaces of said substrate consisting of a plurality of small discrete particles bonded together at their points of contact with each other in at least two layers to define a plurality of connected interstitial pores uniformly distributed throughout the coating, said method comprising:

roughening the coherent metal substrate surfaces desired to be coated,

forming a viscous self-supporting coating of a plurality of layers of at least one metal or at least one thermally-decomposable metal compound particles adhesively bound together and to the substrate,

drying said adhesive to provide a preform on said substrate; and

sintering said preform to cause interconnection of metal particles to each other and to said substrate.

2. The method of claim 1 wherein said metal compound particles are titanium hydride particles, said sintering is effected at a temperature at least sufficient to cause thermal decomposition of said titanium hydride particles and form interconnected metal particles in said coating and hydrogen released in said thermal decomposition is removed from a sintering zone.

3. The method of claim 2 wherein said substrate is constructed of titanium and titanium hydride particles have a particle size of -325 mesh.