High flexibility, kink resistant catheter shaft
An enhanced flexibility catheter shaft having an elongate flexible body with a proximal end, a distal end, and at least one lumen extending therethrough. A distal, flexible section on the body has a ribbed or corrugated tubular membrane having at least a first reinforcement structure, such as a first helical support, on a radially exterior or interior surface of the membrane and optionally a second reinforcement structure, such as a second helical support, on the other of the radially interior or exterior surface of the membrane.
1 . A catheter comprising:
a body having a proximal portion, a distal portion, and a central lumen, in which the distal portion is more flexible than the proximal portion, the body comprising:
an inner tubular membrane defining the central lumen, the inner tubular membrane extending proximally and providing an inner-most lining of the proximal portion, and
one or more reinforcement structures, carried concentrically over the inner tubular membrane, the one or more reinforcement structures providing a proximal support extending proximally along a length of the catheter and being encapsulated in one or more sections of polymer tubing,
wherein the inner tubular membrane in the distal portion forms a continuous helical groove extending around an entire circumference of the catheter forming corrugations that are spaced apart substantially perpendicularly to a longitudinal axis that extends from a proximal end to a distal end of the catheter,
wherein the inner tubular membrane in the proximal portion forms a substantially cylindrical inner liner,
wherein the one or more reinforcement structures, collectively, are carried concentrically over the inner tubular membrane in the distal portion and the proximal portion along an entire length of the catheter,
wherein the catheter has an outer-most surface that is smooth in the distal portion and an inner-most surface formed by the corrugations, the corrugations extend inwardly towards a central longitudinal axis of the central lumen, and
wherein the one or more reinforcement structures includes a helical support or a braided structure.
2 . The catheter of claim 1 , wherein the one or more reinforcement structures include a first reinforcement structure and a second reinforcement structure.
3 . The catheter of claim 2 , wherein a first portion of the first reinforcement structure and a second portion of the second reinforcement structure overlap along the longitudinal axis that extends from the proximal end to the distal end of the catheter.
4 . The catheter of claim 1 , wherein the outer-most surface of the catheter is smooth proximally of the distal portion.
5 . The catheter of claim 1 , wherein the inner tubular membrane comprises ePTFE material, and a wall thickness of the ePTFE is no more than about 0.10 mm.
6 . The catheter of claim 1 , wherein the one or more reinforcement structures includes the helical support, and wherein a depth of the continuous helical groove is at least about 1 times a diameter of wire forming the helical support.
7 . The catheter of claim 1 , wherein the one or more reinforcement structures includes the helical support, and wherein the helical support is positioned in the continuous helical groove in the distal portion such that a helical rib extends through interstitial spaces of the helical support.
8 . The catheter of claim 7 , wherein the one or more reinforcement structures includes the helical support, and wherein a depth of the continuous helical groove of the inner tubular membrane is at least about 1.00 times a diameter of wire forming the helical support.
9 . The catheter of claim 1 , wherein the inner tubular membrane comprises two distinct sections, the two distinct sections comprising a proximal section and a distal section.
10 . The catheter of claim 1 , wherein the one or more reinforcement structures includes the helical support, and wherein the helical support is encapsulated entirely by the one or more sections of polymer tubing.
11 . The catheter of claim 1 , wherein the one or more reinforcement structures includes the helical support, and wherein the helical support terminates in the distal portion.
12 . The catheter of claim 1 , wherein the one or more reinforcement structures includes the helical support, and wherein the helical support extends proximally of the distal portion to provide support to the proximal portion to prevent kinking and the helical support is encapsulated in the proximal portion in the one or more sections of polymer tubing.
13 . The catheter of claim 1 , wherein the one or more reinforcement structures includes the helical support, and wherein the helical support is comprised of Nitinol wire and has a cross section in a radial direction of no more than about 0.15 mm (0.006 inches).
14 . The catheter of claim 1 , wherein the one or more reinforcement structures includes the helical support, and wherein the helical support comprises a same material along an entire length of the helical support.
15 . The catheter of claim 1 , wherein the inner tubular membrane has a thickness of no more than about 0.10 mm (0.004 inches).
16 . A catheter comprising:
a body having a proximal portion, a distal portion, and a central lumen, in which the distal portion is more flexible than the proximal portion, the body comprising:
an inner tubular membrane surrounding the central lumen, the inner tubular membrane extending proximally and providing an inner-most lining of the proximal portion, and
one or more reinforcement structures, carried concentrically over the inner tubular membrane, the one or more reinforcement structures providing a proximal support extending proximally along a length of the catheter and being encapsulated in one or more sections of polymer tubing,
wherein the inner tubular membrane in the distal portion forms a continuous helical groove portion extending around an entire circumference of the catheter, the distal portion of the body including an outer-most surface that is smooth and an inner-most surface formed by inwardly facing helical corrugations,
wherein the one or more reinforcement structures are provided within the helical corrugations of the distal portion,
wherein the inner tubular membrane in the proximal portion forms a non-corrugated inner liner,
wherein the one or more reinforcement structures, collectively, are carried concentrically over the inner tubular membrane in the distal portion and the proximal portion along an entire length of the catheter,
wherein the one or more reinforcement structures includes a helical support or a braided structure, and
wherein the helical corrugations are spaced apart substantially perpendicularly to a longitudinal axis that extends from a proximal end to a distal end of the catheter.
17 . The catheter of claim 16 , wherein the one or more sections of polymer tubing cover an entire outer surface of the inner tubular membrane, and form the outer-most surface of the catheter.
18 . The catheter of claim 16 , wherein the one or more reinforcement structures includes the helical support, and wherein the helical support is encapsulated entirely by the one or more sections of polymer tubing.
19 . A catheter comprising:
an elongate tubular body having a proximal portion, a distal portion, and a central lumen, in which the distal portion is more flexible than the proximal portion, the elongate tubular body comprising:
an inner tubular membrane defining the central lumen, the inner tubular membrane extending proximally and providing an inner-most lining of the proximal portion, and
one or more reinforcement structures, collectively, carried concentrically over the inner tubular membrane in the distal portion and the proximal portion along an entire length of the catheter,
wherein the inner tubular membrane in the distal portion forms a continuous helical groove extending around an entire circumference of the catheter forming corrugations that are spaced apart substantially perpendicularly to a longitudinal axis that extends from a proximal end to a distal end of the catheter, the distal portion including an outer-most surface that is smooth,
wherein the corrugations form the inner-most surface of the distal portion and extend towards a longitudinal axis of the central lumen, and
wherein the one or more reinforcement structures includes a helical support or a braided structure.
20 . The catheter of claim 19 , wherein the inner tubular membrane comprises two distinct sections, the two distinct sections comprising a proximal section and a distal section.