Catheter with composite stiffener
A catheter comprising an elongate tubular member having a proximal end, a distal end, and a passageway defining a lumen extending between the proximal and distal ends. The elongate tubular member comprises a relatively stiff proximal section and a relatively flexible distal section. The proximal section includes an inner tubular liner, a first stiffener comprising a metal alloy, and a second stiffener comprising a non-metal alloy. The first and second stiffeners are coaxially wound exterior to the proximal inner liner. The distal section includes a distal inner tubular liner and the second stiffener coaxially wound exterior to the distal inner liner. The first stiffener terminates before reaching the distal section.
1. A catheter comprising an elongate tubular member having a proximal end, a distal end, and a lumen extending therebetween, the lumen defined by an inner tubular liner, the elongate tubular member comprising:
a relatively stiff proximal section comprising a metallic stiffening ribbon and a non-metallic stiffening ribbon, the metallic and non-metallic stiffening ribbons being disposed over an outer surface of the inner tubular liner,
a relatively flexible distal section comprising the non-metallic stiffening ribbon being disposed over the outer surface of the inner tubular liner, the metallic stiffening ribbon terminating before reaching the distal section such that the distal section is devoid of metallic stiffening ribbon.
2. The catheter of claim 1 further comprising an outer cover having a proximal end and a distal end, the metallic and non-metallic stiffening ribbons being interposed between the inner tubular member and the outer cover.
3. The catheter of claim 1 wherein the metallic stiffening ribbon is helically disposed about the inner tubular member.
4. The catheter of claim 1 , wherein the pitch of the at least one metallic stiffening ribbon varies along at least a portion of the elongate tubular member.
5. The catheter of claim 1 , wherein the non-metallic stiffening ribbon is helically disposed about the inner tubular member and wherein the pitch of the at least one non-metallic stiffening ribbon varies along at least a portion of the elongate shaft.
6. The catheter of claim 1 , wherein the at least one non-metallic stiffening ribbon is helically wound over the at least one metallic stiffening ribbon.
7. The catheter of claim 1 , wherein the at least one metallic stiffening ribbon is helically wound over the at least one non-metallic stiffening ribbon.
8. The catheter of claim 1 , wherein the at least one non-metallic stiffening ribbon is interwoven with the at least one metallic stiffening ribbon through the proximal section of the elongate shaft.
9. The catheter of claim 1 , wherein the at least one non-metallic stiffening ribbon is coaxially wound about the inner liner in a first direction, and the at least one metallic stiffening ribbon is coaxially wound about the inner liner in a second direction opposite the first direction.
10. The catheter of claim 1 , wherein the proximal section includes at least four metallic stiffening ribbons.
11. The catheter of claim 1 , wherein the distal section includes at least four non-metallic stiffening ribbons.
12. The catheter of claim 1 , wherein the tubular member includes the same number of metallic stiffening ribbons as non-metallic stiffening ribbons.
13. The catheter of claim 1 , wherein the tubular member includes a number of metallic stiffening ribbons and a number of non-metallic stiffening ribbons that is different from the number of metallic stiffening ribbons.
14. The catheter of claim 13 , wherein the tubular member includes an even number of metallic stiffening ribbons and an even number of non-metallic stiffening ribbons.
15. The catheter of claim 13 , wherein the number of metallic stiffening ribbons is greater than the number of non-metallic stiffening ribbons.
16. The catheter of claim 1 , wherein the non-metallic stiffening ribbon comprises a material capable of undergoing permanent deformation upon exposure to steam.
17. The catheter of claim 1 , wherein the metallic stiffening ribbon comprises a superelastic alloy.
18. The catheter of claim 1 , wherein the metallic stiffening ribbon comprises stainless steel.
19. The catheter of claim 1 , wherein the metallic stiffening ribbon comprises a material selected from the group consisting of gold, platinum, and copper.
20. The catheter of claim 1 , wherein the non-metallic stiffening ribbon has a cross-section extending generally parallel to a longitudinal axis of the elongate shaft in the proximal section, and extending generally perpendicular to the longitudinal axis of the elongate shaft in the distal section.