Inflatable balloon and cover
The present disclosure describes implantable medical devices comprising covers, such as a balloon cover. Such devices can comprise a first layer of a porous polymeric material, such as ePTFE, surrounded by layers of a porous polymeric material having an imbibed elastomer, such as polyurethane. The cover can be used to assist in deployment of an expandable implant, such as a stent-graft, within the body of the patient.
1. A medical balloon comprising:
a balloon and an outer cover, the outer cover comprising:
a plurality of inner layers, each of the plurality of inner layers comprising a porous polymer that is not imbibed with an elastomeric component, wherein all of the plurality of inner layers are defined by a portion of a single continuous sheet of the porous polymer oriented circumferentially about a longitudinal axis of the outer cover, and
at least one composite layer comprising a porous polymer imbibed on a first surface with an elastomeric component, the porous polymer of the at least one composite layer defined by another portion of the single continuous sheet of the porous polymer oriented circumferentially about the longitudinal axis of the outer cover,
wherein the at least one composite layer is positioned externally to plurality of inner layers, and
wherein an outer surface of the outer cover is defined by a surface of the composite layer that is substantially free of elastomer.
2. The medical balloon of claim 1 , wherein the plurality of inner layers have a combined thickness at least twice that of a thickness of the at least one composite layer.
3. The medical balloon of claim 1 , wherein the outer cover further comprises at least one pleat aligned along a longitudinal axis.
4. The medical balloon of claim 1 , wherein the elastomeric component of the at least one composite layer comprises polyurethane.
5. The medical balloon of claim 1 , wherein the porous polymer comprises expanded polytetrafluoroethylene (ePTFE).
6. The medical balloon of claim 1 , wherein the outer cover coaxially surrounds the medical balloon, and wherein an inner surface of outer cover substantially conforms to an outer surface of the medical balloon.
7. The medical balloon of claim 1 wherein the outer cover is coupled to a catheter tube having a continuous lumen.
8. A medical balloon comprising:
a balloon and an outer cover, the outer cover comprising:
a porous polymer layer that is not imbibed with an elastomeric component, wherein the porous polymer layer is defined by a portion of a single continuous sheet of the porous polymer oriented circumferentially about a longitudinal axis of the outer cover, and
a composite layer comprising a porous polymer imbibed on a first surface with an elastomeric component, the porous polymer of the composite layer defined by another portion of the single continuous sheet of the porous polymer oriented circumferentially about the longitudinal axis of the outer cover,
wherein the composite layer is positioned externally to the porous polymer layer, and
wherein an outer surface of the outer cover is defined by a surface of the composite layer that is substantially free of elastomer.
9. The medical balloon of claim 8 , wherein the porous polymer layer comprises at least two circumferentially oriented layers of the single continuous sheet.
10. The medical balloon of claim 8 , wherein the porous polymer layer has a thickness that is at least twice a thickness of the composite layer.