Microfabricated catheter with improved bonding structure

1. A medical device, comprising:

an elongated tubular member having a length, an inner surface defining a lumen, a proximal end, and a distal end, the tubular member including a monolithic body having a length and including a plurality of slots formed therein;

a tubular liner disposed within the elongated tubular member, the liner having a length, an outer surface, and an inner surface defining a lumen, wherein the outer surface is spaced from the inner surface of the tubular member such that a space is defined therebetween;

a plurality of discrete bonding members disposed in the space and attaching the elongated tubular member to the tubular liner, wherein each of the plurality of bonding members is within 15 centimeters or less of an adjacent bonding member along the length of the tubular member;

wherein the plurality of discrete bonding members include a weld, adhesive bond, braze, crimp, solder bond, epoxy bond, bonding substance, thermal bond, or combinations thereof that fixedly attach the elongated tubular member to the tubular liner;

wherein a first group of bonding members are disposed along a first portion of the liner to provide the medical device with a first flexibility, the first group of bonding members including a pair of bonding members disposed opposite each other at a first longitudinal position along the liner and a second group of bonding members are disposed along a second portion of the liner, the second group of bonding members having a different number of bonding members from the first group of bonding members, the second group of bonding members including three or more bonding members that are equally spaced about the liner at a second longitudinal position along the liner different from the first longitudinal position so as to provide the medical device with a second flexibility different from the first flexibility; and

wherein the number of bonding members per unit length decreases along the length of the liner and forms a smooth transition between the first flexibility and the second flexibility.

2. The medical device of claim 1 , wherein the space has a volume and wherein the bonding members occupy 50% or less of the volume.

3. The medical device of claim 1 , wherein the space has a volume and wherein the bonding members occupy 40% or less of the volume.

4. The medical device of claim 1 , wherein the space has a volume and wherein the bonding members occupy 30% or less of the volume.

5. The medical device of claim 1 , wherein the space has a volume and wherein the bonding members occupy 20% or less of the volume.

6. The medical device of claim 1 , wherein the space has a volume and wherein the bonding members occupy 10% or less of the volume.

7. The medical device of claim 1 , wherein at least a portion of the space remains unfilled by the bonding members.

8. The medical device of claim 1 , wherein at least some of the bonding members extend circumferentially about the liner.

9. The medical device of claim 1 , wherein at least some of the bonding members extend only partially circumferentially about the liner.

10. The medical device of claim 9 , wherein two or more bonding members that extend only partially circumferentially about the liner are disposed at the same longitudinal position along the liner.

11. The medical device of claim 9 , wherein the pair of bonding members of the first group of bonding members is defined by a pair of partially circumferential bonding members disposed opposite one another at the same longitudinal position along the liner.

12. The medical device of claim 11 , wherein the three or more bonding members of the second group of bonding is defined by three or more partially circumferential bonding members disposed opposite one another at the same longitudinal position along the liner.

13. The medical device of claim 1 , wherein at least one of the bonding members includes a bonding member that extends helically along the outer surface of the liner.

14. The medical device of claim 13 , wherein groups of beams are defined in the tubular member between slots at the same longitudinal location, wherein the groups of beams follow a helical pattern about the tubular member, and wherein both the groups of beams and the bonding member that extends helically along the outer surface of the liner are oriented in substantially the same direction.

15. The medical device of claim 13 , wherein groups of beams are defined in the tubular member between slots at the same longitudinal location, wherein the groups of beams follow a helical pattern about the tubular member, and wherein both the groups of beams and the bonding member that extends helically along the outer surface of the liner are oriented in different directions.

16. The medical device of claim 1 , wherein each of the plurality of bonding members is within 10 centimeters or less of an adjacent bonding member along the length of the tubular member.

17. The medical device of claim 1 , wherein each of the plurality of bonding members is within 5 centimeters or less of an adjacent bonding member along the length of the tubular member.

18. A medical device, comprising:

an elongated tubular member having an inner surface defining a lumen, a proximal end, and a distal end, the tubular member including a monolithic body having a length and including a plurality of slots formed therein;

a tubular liner disposed within at least a portion of the elongated tubular member such that the tubular member overlaps the liner along an overlapping portion having a length, the liner having an outer surface, and an inner surface defining a lumen, wherein the outer surface of the tubular liner is spaced from the inner surface of the elongated tubular member along the overlapping portion such that a space is defined therebetween; and

a plurality of discrete, axially discontinuous bonding members disposed in the space and attaching the elongated tubular member to the tubular liner, wherein the plurality of bonding members are disposed such that there is at least one bonding member at intervals of 15 centimeters or less along the entire length of the overlapping portion;

wherein the plurality of discrete bonding members physically, chemically, or both physically and chemically bond the elongated tubular member to the tubular liner;

wherein at least some of the bonding members extend only partially circumferentially about the liner;

wherein a first group of bonding members is defined that includes two or more bonding members that extend only partially circumferentially about the liner and are disposed at the same longitudinal position along the length of the liner; and

wherein the bonding members decrease in frequency along the length of the liner so as to define a smooth transition in flexibility of the medical device along the length of the liner.

19. The catheter of claim 18 , wherein at least some of the bonding members extend circumferentially about the liner.

20. The catheter of claim 18 , wherein a second group of bonding members is defined adjacent the first group that includes two or more bonding members that extend only partially circumferentially about the liner and are disposed at the same longitudinal position along the length of the liner, wherein the second group is rotated relative to the first group.

21. The catheter of claim 18 , wherein the plurality of bonding members are disposed such that there is at least one bonding member at intervals of 10 centimeters or less along the entire length of the overlapping portion.

22. The catheter of claim 18 , wherein the plurality of bonding members are disposed such that there is at least one bonding member at intervals of 5 centimeters or less along the entire length of the overlapping portion.