Intravascular devices supporting an arteriovenous fistula
Medical devices and methods for forming an arteriovenous (AV) fistula include a stent having an arterial tubular portion and vein supporting tongue connected by a pre-shaped connector and a venous frustoconical stent having a distal end for maintaining a take-off angle for the venous portion of the AV fistula. Also disclosed is an angled balloon for assisting with the formation of the AV fistula. The medical devices disclosed herein support an AV fistula formation having a desired take off angle of about 30 degrees, or between about 15 and 45 degrees.
1. An intraluminal medical device, comprising:
a stent or scaffold, including
a tubular portion,
a tongue having a proximal end arc length and a distal end arc length, each spanning an angle of 270, 180 or 90 degrees, or about 90-180 degrees, wherein the tongue has a taper of ratio of between 1:1.5 to 1:3 such that the distal end arc length is lamer than the proximal end arc length; and
a connector connecting the tongue to the tubular portion;
wherein the connector is pre-shaped to cause the tongue to form an angle (Θ) of about 30 or between about 15 to 45 degrees with respect to a bore axis of the tubular portion.
2. The medical device of claim 1 , wherein the tubular portion is a radially expandable body having a plurality of rings interconnected by struts.
3. The medical device of claim 1 , wherein the connector comprises a plurality of link elements.
4. The medical device of claim 1 , wherein the connector includes a first plurality of links interconnected by a second plurality of links through a transitional structure.
5. The medical device of claim 1 , wherein the tongue is a paddle.
6. The medical device of claim 1 , wherein the connector includes a central, straight connector and two S-shaped connectors surrounding the straight connector.
7. A catheter comprising the medical device of claim 1 retained within a sheath at a distal end of the catheter.
8. The catheter of claim 7 , wherein a first sheath constrains the tubular portion and a second sheath constrains the tongue.
9. The catheter of claim 7 , wherein the tubular portion and tongue are retained between a proximal ledge and a distal ledge.
10. A medical device, comprising
a catheter having a distal end and a proximal end, wherein the distal end is made with a curve such that the distal end curves through an angle of 60 to 90 degrees with respect to the proximal end; and
the stent or scaffold of claim 1 mounted on the catheter.
11. The medical device of claim 10 , further comprising
a first sheath disposed over the tubular portion,
a second sheath disposed over the tongue,
a pusher connected to the first sheath, and
a rod, tether or tube connected to the second sheath,
wherein the first sheath and the second sheath are separately removable from the tubular portion and the tongue, respectively, using the pusher and tether, rod or tube.
12. The medical device of claim 11 , wherein the pusher has a distal tip connected to the first sheath.
13. The medical device of claim 11 , wherein the catheter further comprises a member having a lumen for passage of the pusher, the member having a first and second ledge, the first ledge circumscribing a bore axis for the lumen and the second ledge at least partially surrounding the bore axis, wherein the stent or scaffold is disposed between the first and second ledge.
14. The medical device of claim 10 , wherein the tubular portion and tongue are self-expanding.