Compliant implantable medical devices and methods of making same
View Patent ↗Implantable medical grafts fabricated of metallic or pseudometallic films of biocompatible materials having a plurality of microperforations passing through the film in a pattern that imparts fabric-like qualities to the graft or permits the geometric deformation of the graft. The implantable graft is preferably fabricated by vacuum deposition of metallic and/or pseudometallic materials into either single or multi-layered structures with the plurality of microperforations either being formed during deposition or after deposition by selective removal of sections of the deposited film. The implantable medical grafts are suitable for use as endoluminal or surgical grafts and may be used as vascular grafts, stent-grafts, skin grafts, shunts, bone grafts, surgical patches, non-vascular conduits, valvular leaflets, filters, occlusion membranes, artificial sphincters, tendons and ligaments.
1. An implantable medical device, comprising: a. a non-coiled tubular body member consisting essentially of a metallic or pseudometallic material film having a first surface, a second surface and a thickness intermediate the first surface and the second surface, the thickness being between 0.1 μm to 75 μm; and b. a plurality of microperforations passing through the thickness of the body member and communicating between the first surface and the second surface, whereby said plurality of microperforations are configured to geometrically deform, thereby allowing diametric expansion and both circumferential and longitudinal compliance of the body member.
2. The implantable medical device according to claim 1 , wherein the body member further comprises a generally torroidal annular ring-shaped member.
3. The implantable medical device according to claim 1 , wherein the thickness of the body member between 0.1 μm and 50 μm.
4. The implantable medical device according to claim 1 , wherein the plurality of microperforations are arrayed in at least one pattern sufficient to impart at least one of compliance and pliability to the body member.
5. The implantable medical device according to claim 4 , wherein said plurality of microperforations further comprise a plurality of slots arrayed substantially parallel to at least one of a longitudinal axis and a circumferential direction of the body member.
6. The implantable medical device according to claim 5 , wherein each of the plurality of slots has a generally elongate linear configuration.
7. The implantable medical device according to claim 6 , wherein each of the plurality of slots further comprise terminal fillets positioned at opposing ends of each of the plurality of slots, wherein the terminal fillets include a diameter larger than a width of the plurality of slots.
8. The implantable medical device according to claim 7 , wherein the elongated slot configuration further comprises a first plurality of slots oriented parallel to the longitudinal axis of the body member and a second plurality of slots oriented parallel to the circumferential axis of the body member, the first plurality of slots and the second plurality of slots being positioned generally orthogonal relative to one another.
9. The implantable medical device according to claim 1 , wherein said plurality of microperforations further comprise a plurality of generally diamond-shaped openings.
10. The implantable medical device according to claim 1 , wherein each of the plurality of microperforations have an open surface area less than about 2 mm 2 when the body member is in an undeformed state.
11. The implantable medical device according to claim 1 , wherein the plurality of microperforations create a total open surface area of the body member in an undeformed state between about 0.001 to 99%.
12. The implantable medical device according to claim 1 , wherein the body member thickness is within the range of about 0.1 μm to 75 μm.
13. The implantable medical device according to claim 12 , wherein the body member thickness is within the range of about 1 μm to 50 μm.
14. A method of fabricating the body member according to claim 1 , comprising the steps of: a. Providing a sacrificial substrate suitable; b. Vacuum depositing at least one of a metallic and pseudometallic biocompatible material onto the sacrificial substrate thereby forming a film of the biocompatible material; c. Imparting a plurality of microperforations passing through the film of biocompatible material thereby forming the implantable medical device; and d. Separating the sacrificial substrate from the formed implantable medical device.
15. The method according to claim 14 , wherein the step c. further comprises the step of removing portions of the biocompatible material to form the plurality of microperforations.
16. The method according to claim 14 , wherein the removing step is selected from the steps of chemical etching, laser ablation and electrical discharge machining.
17. A method of fabricating the body member according to claim 1 , comprising the steps of: a. providing a pre-existing blank of at least one of a biocompatible metallic and pseudometallic material; b. removing sections of the pre-existing blank material to form a plurality of microperforations passing through the pre-existing blank material.