Medical cannulae, delivery systems and methods
The disclosure relates to cannulae, delivery systems, methods of making cannulae, and methods of making delivery systems. A delivery system comprises an elongate outer tubular member defining an outer tubular member lumen, a cannula having a circumferential wall extending between a proximal end and a distal end and defining an interior lumen, and an intraluminal medical device disposed within the outer tubular member lumen distal to the cannula and not about the cannula. A pattern of openings arranged in an interrupted spiral extends circumferentially along the cannula.
1. A delivery system, comprising
a cannula, comprising:
an elongate tubular member having a lengthwise axis and a circumferential wall extending between a proximal end and a distal end and defining an interior lumen;
the elongate tubular member having an intermediate axial portion extending between a proximal axial portion that includes the proximal end and a distal axial portion that includes the distal end; and
a pattern of openings in the circumferential wall of the elongate tubular member, the pattern of openings comprising a first plurality of openings arranged in an interrupted spiral that extends circumferentially along the intermediate axial portion of the elongate tubular member;
a second pattern of openings in the circumferential wall of the elongate tubular member, the second pattern of openings comprising a second plurality of openings that extends linearly along only a single side of the intermediate axial portion of the elongate tubular member, the openings of the second plurality of openings interspersed with the openings of the first plurality of openings;
wherein the proximal axial portion and the distal axial portion are free of the pattern of openings and comprise an uninterrupted circumferential wall; and
wherein the proximal portion is longer than the distal portion;
an elongate outer tubular member defining an outer tubular member lumen; and
an intraluminal medical device disposed within the outer tubular member lumen;
wherein the cannula is disposed within the elongate outer tubular member lumen such that the cannula is disposed proximal to the intraluminal medical device and the intraluminal medical device is not disposed about the cannula.
2. The delivery system of claim 1 , wherein each opening of the first plurality of openings comprises an elongate slit that extends through the entire thickness of the circumferential wall of the elongate tubular member.
3. The delivery system of claim 1 , wherein a portion of the circumferential wall is disposed between openings in immediately adjacent revolutions of the interrupted spiral; and
wherein each opening of the first plurality of openings has an axial width;
wherein the portion has a length along the lengthwise axis of the elongate tubular member that is between about 0.5 times and about 40 times the axial width of the openings in the immediately adjacent revolutions of the interrupted spiral.
4. The delivery system of claim 3 , wherein the portion has a length along the lengthwise axis of the elongate tubular member that is between about 1 times and about 5 times the axial width of the openings in the immediately adjacent revolutions of the interrupted spiral.
5. The delivery system of claim 3 , wherein the portion has a length along the lengthwise axis of the elongate tubular member that is between about 1.5 times and about 2.5 times the axial width of the openings in the immediately adjacent revolutions of the interrupted spiral.
6. The delivery system of claim 3 , wherein the portion has a length along the lengthwise axis of the elongate tubular member that is about 2 times the axial width of the openings in the immediately adjacent revolutions of the interrupted spiral.
7. The delivery system of claim 1 , wherein portions of the circumferential wall are disposed between immediately adjacent revolutions of the interrupted spiral; and
wherein the portions have uniform lengths along the lengthwise axis of the elongate tubular member.
8. The delivery system of claim 1 , wherein portions of the circumferential wall are disposed between immediately adjacent revolutions of the interrupted spiral; and
wherein the portions have varying lengths along the lengthwise axis of the elongate tubular member.
9. The delivery system of claim 1 , wherein a portion of the circumferential wall is disposed between immediately adjacent openings within a revolution of the interrupted spiral; and
wherein each opening of the first plurality of openings has an axial width;
wherein the portion has a circumferential length along the elongate tubular member that is between about 0.1 times and about 2 times the axial width of the immediately adjacent openings within a revolution of the interrupted spiral.
10. The delivery system of claim 9 , wherein the portion has a circumferential length along the elongate tubular member that is between about 0.25 times and about 1.5 times the axial width of immediately adjacent openings within a revolution of the interrupted spiral.
11. The delivery system of claim 9 , wherein the portion has a circumferential length along the elongate tubular member that is between about 0.5 times and about 1.25 times the axial width of the immediately adjacent openings within a revolution of the interrupted spiral.
12. The delivery system of claim 9 , wherein the portion has a circumferential length along the elongate tubular member that is about 0.5 times the axial width of the immediately adjacent openings within a revolution of the interrupted spiral.
13. The delivery system of claim 1 , wherein portions of the circumferential wall are disposed between immediately adjacent openings within a revolution of the interrupted spiral; and
wherein the portions have uniform circumferential lengths along the elongate tubular member.
14. The delivery system of claim 1 , wherein portions of the circumferential wall are disposed between immediately adjacent openings within a revolution of the interrupted spiral; and
wherein the portions have varying circumferential lengths along the elongate tubular member.
15. The delivery system of claim 1 , further comprising a conical distal tip secured to the distal end of the elongate tubular member.
16. The delivery system of claim 1 , further comprising a double-tapered distal tip secured to the distal end of the elongate tubular member;
wherein the double-tapered distal tip has an outer diameter that is greater than an outer diameter of the elongate tubular member.
17. The delivery system of claim 1 , wherein the elongate tubular member comprises a metal.
18. The delivery system of claim 17 , wherein the metal comprises stainless steel.