Integrated coil vascular devices
The present disclosure relates to vascular devices such as guidewires and microcatheters having integrated coil sections for optimizing torquability, flexibility, and ability to shape and maintain the distal tip. A guidewire device includes a core and a tube structure coupled to the core such that at least a portion of the core passes into the tube structure. A distal section of the tube structure includes a spiral cut arrangement that configures the distal section as an integral coil integrally incorporated as part of the tube structure. The integrated coil configuration increases the flexibility of the tube structure to reduce the tendency of resilient forces from the tube structure to disrupt a shaped distal tip of the guidewire device.
1 . A microcatheter device including a gradient flexibility profile that generally increases in flexibility toward a distal end of the device, the device comprising:
a tube structure that extends between a proximal terminal end and a distal terminal end, wherein the tube structure includes a transition point, a distal section that extends from the distal terminal end to the transition point, a proximal section that extends from the proximal terminal end to the transition point, and a wall defining an interior lumen;
a single integral coil, wherein the single integral coil is disposed at the distal section of the tube structure and is integrally formed as part of the tube structure as a result of a spiral cut pattern along a length of the distal section of the tube structure, the single integral coil providing the distal section of the tube structure greater flexibility than the proximal section of the tube structure; and
a plurality of cuts in the proximal section of the tube structure, the plurality of cuts extending through the wall and exposing the lumen to define a plurality of axially extending beams and a plurality of circumferentially extending rings, wherein the plurality of cuts of the proximal section consist of cuts that form the axially extending beams and circumferentially extending rings such that cuts forming axially extending beams and circumferentially extending rings are the only cuts in the tube structure between the proximal terminal end and the transition point.
2 . The microcatheter device of claim 1 , wherein the proximal section includes a cut pattern of the axially extending beams and circumferentially extending rings selected from the group consisting of a two-beam cut pattern, a three-beam cut pattern, a cut pattern of more than three beams, a distributed beam arrangement, and combinations thereof.
3 . The microcatheter device of claim 1 , wherein the integral coil includes turns having widths that progressively widen or progressively narrow along a length of the tube structure toward a distal end of the device.
4 . The microcatheter device of claim 1 , wherein the integral coil includes gaps between turns that progressively widen or progressively narrow along a length of the tube structure toward a distal end of the device.
5 . The microcatheter device of claim 1 , further comprising a polymer layer encapsulating at least a portion of the integral coil.
6 . The microcatheter device of claim 5 , wherein the polymer material includes a radiopaque doping material.
7 . The microcatheter device of claim 1 , wherein the axially extending beams and circumferentially extending rings provide the proximal section higher torquability than the distal section and lower flexibility than the distal section.
8 . The microcatheter device of claim 1 , wherein the proximal section includes a two-beam section transitioning to a one-beam section, along a proximal to distal direction.
9 . The microcatheter device of claim 1 , wherein at least a portion of a length of the integral coil includes a plurality of bridges each connecting a pair of adjacent turns of the integral coil.
10 . The microcatheter device of claim 9 , wherein the bridges are spaced apart every 45 degrees to about every 90 degrees around the tube structure.
11 . The microcatheter device of claim 1 , wherein the microcatheter device omits an inner core member.
12 . A microcatheter device comprising a gradient flexibility profile that generally increases in flexibility toward a distal end of the device, the device comprising:
a tube structure comprising a wall defining an interior lumen, a distal section, a proximal section, and a transition point between the distal section and the proximal section, wherein the proximal section is longer than the distal section, and wherein the distal section extends from the transition point to a distal terminal end of the tube structure and the proximal section extends from the transition point to a proximal terminal end of the tube structure;
an integral coil extending from the distal end of the tube structure to the transition point, the integral coil being integrally formed as part of the tube structure as a result of a spiral cut pattern along a length of the distal section of the tube structure, the integral coil providing the distal section of the tube structure greater flexibility than the proximal section of the tube structure; and
a plurality of cuts formed in the proximal section, the plurality of cuts forming a plurality of axially extending beams and a plurality of circumferentially extending rings, wherein the plurality of cuts of the proximal section consist of cuts that form the axially extending beams and circumferentially extending rings such that cuts forming axially extending beams and circumferentially extending rings are the only cuts in the tube structure between the proximal terminal end and the transition point.
13 . The microcatheter device of claim 12 , wherein the plurality of axially extending beams and plurality of circumferentially extending rings form a two-beam cut pattern, a three-beam cut pattern, a cut pattern of more than three beams, a distributed beam arrangement, or combination thereof.
14 . The microcatheter device of claim 12 , wherein the integral coil includes turns having widths that progressively widen or progressively narrow along a length of the tube structure toward a distal end of the device and/or includes gaps between turns that progressively widen or progressively narrow along a length of the tube structure toward a distal end of the device.
15 . The microcatheter device of claim 12 , wherein at least a portion of a length of the integral coil includes a plurality of bridges each connecting a pair of adjacent turns of the integral coil.
16 . The microcatheter device of claim 15 , wherein the bridges are spaced apart every 45 degrees to about every 90 degrees around the tube structure.
17 . The microcatheter device of claim 12 , further comprising a separate coil, wherein individual turns of the separate coil are disposed within gaps defined by the integral coil such that the separate coil is intermeshed with the integral coil.
18 . The microcatheter device of claim 17 , wherein the separate coil is formed at least partially from a radiopaque material.
19 . The microcatheter device of claim 12 , wherein fenestrations between the rings of the proximal section are filled with a polymer matrix.
20 . The microcatheter device of claim 19 , wherein the polymer matrix forms around an external portion of the tube structure, fills the fenestrations between the rings of the proximal section, and coats an inner surface of the tube structure.