Self-supporting laminated films, structural materials and medical devices manufactured therefrom and method of making same
View Patent ↗Metal foils, wires, and seamless tubes with increased mechanical strength are provided. As opposed to wrought materials that are made of a single metal or alloy, these materials are made of two or more layers forming a laminate structure. Laminate structures are known to increase mechanical strength of sheet materials such as wood and paper products and are used in the area of thin films to increase film hardness, as well as toughness. Laminate metal foils have not been used or developed because the standard metal forming technologies, such as rolling and extrusion, for example, do not lend themselves to the production of laminate structures. Vacuum deposition technologies can be developed to yield laminate metal structures with improved mechanical properties. In addition, laminate structures can be designed to provide special qualities by including layers that have special properties such as superelasticity, shape memory, radio-opacity, corrosion resistance etc. Examples of articles which may be made by the inventive laminate structures include implantable medical devices that are fabricated from the laminated deposited films and which present a blood or body fluid and tissue contact surface that has controlled heterogeneities in material constitution. An endoluminal stent-graft and web-stent that is made of a laminated film material deposited and etched into regions of structural members and web regions subtending interstitial regions between the structural members. An endoluminal graft is also provided which is made of a biocompatible metal or metal-like material. The endoluminal stent-graft is characterized by having controlled heterogeneities in the stent material along the blood flow surface of the stent and the method of fabricating the stent using vacuum deposition methods.
1. An implantable medical device comprising a self-supporting structural member fabricated of a plurality of laminated layers of at least one biocompatible material, wherein the plurality of laminated layers forms a substantially monolithic structure and the self-supporting structural member further comprises a stent-graft, wherein the stent-graft further comprises
a stent comprising a plurality of interconnected structural elements forming a generally tubular member having a luminal surface, an abluminal surface, a proximal end and a distal end, and
a graft comprising a film projecting outwardly from at least one of the proximal end and the distal end of the stent and along a longitudinal axis of the stent.
2. The implantable medical device according to claim 1 , wherein the stent graft is formed from a metal or metal-like material.
3. The implantable medical device according to claim 1 , wherein the film is everted from the at least one of the proximal end and the distal end of the stent over one of the luminal surface and the abluminal surface of the stent and joined to an opposing one of the proximal end and the distal end from which the graft projects.
4. The implantable medical device according to claim 2 , wherein the metal or metal-like material is selected from the group consisting of titanium, vanadium, aluminum, nickel, tantalum, zirconium, chromium, silver, gold, silicon, magnesium, niobium, scandium, platinum, cobalt, palladium, manganese, molybdenum and alloys thereof, zirconium-titanium-tantalum alloys, nitinol, and stainless steel.
5. An implantable medical device comprising a self-supporting structural member fabricated of a plurality of laminated layers of at least one biocompatible material, wherein the plurality of laminated layers forms a substantially monolithic structure and the self-supporting structural member further comprises a stent-graft, the stent-graft further comprising a tubular member comprising stent regions and graft regions, wherein the stent regions further comprise a plurality of structural elements, wherein each structural element is comprised of a plurality of laminated layers of biocompatible material, and the graft regions further comprise at least one of the plurality of laminated layers of the biocompatible material forming the structural members of the stent regions, and wherein
the graft regions subtend interstitial spaces between adjacent pairs of the plurality of structural members of the stent regions, and
the implantable medical device further comprising a plurality of openings passing through the graft, the plurality of openings being sized to permit migration of cellular and sub-cellular matter therethrough.
6. The implantable medical device according to claim 5 , wherein the stent-graft is formed from a metal or metal-like material.
7. The implantable medical device according to claim 6 , wherein the metal or metal-like material is selected from the group consisting of titanium, vanadium, aluminum, nickel, tantalum, zirconium, chromium, silver, gold, silicon, magnesium, niobium, scandium, platinum, cobalt, palladium, manganese, molybdenum and alloys thereof, zirconium-titanium-tantalum alloys, nitinol, and stainless steel.