Vessel shaping devices and methods
Disclosed is a medical device for shaping a vessel accommodated therein in a predetermined form, wherein said vessel includes a vein and an artery which are connected at a artifactual vascular junction thereof. The device includes an external vascular support ( 100 ) having at least one vascular support wall for accommodating an exterior vessel wall of a vessel therein when implanted. The support includes an arterial portion ( 1304 ) for apposition with said artery when accommodated therein, and/or a venous portion ( 1302 ) for apposition with said vein when accommodated therein. The venous portion ( 1302 ) and/or said arterial portion ( 1304 ) are shaped at a junction thereof to provide a vessel rounding to at least a portion of said vessel junction when in apposition with the latter upon implantation of said device for said vessel shaping. Corresponding methods are also disclosed. Thus dysfunction or failure of a vessel of the artifactual vascular junction may be reduced, minimized, or eliminated.
1. An external vascular support for shaping a vein-artery junction between an artery and a vein anastomosed to the artery, the support comprising:
an arterial portion that is shaped to be in apposition with an exterior wall of the artery when the artery is accommodated within a lumen of the arterial portion; and
a venous portion that is shaped to be in apposition with an exterior wall of the vein when the vein is accommodated within a lumen of the venous portion; and
a support junction portion that is defined by a physical connection between the arterial portion and the venous portion, and is shaped to be in apposition with an exterior wall of the vein-artery junction when the vein-artery junction is accommodated within a lumen of the support junction portion;
wherein said arterial portion and/or said venous portion comprises at least one protrusion configured to press onto the exterior vessel wall of the artery and/or the vein, the protrusion being positioned and dimensioned to reduce turbulence of blood flow inside the artery and/or the vein.
2. The external vascular support of claim 1 , wherein the support junction portion is such that, upon implantation of the support, is shaped to maintain the vein at an acute angle to the artery.
3. The external vascular support of claim 2 , wherein the at least one protrusion is located on the support junction portion such that, upon implantation of the support, the at least one protrusion is positioned along the venous portion on a side having the acute angle and near the arterial portion.
4. The external vascular support of claim 2 , wherein the at least one protrusion is located on the arterial portion such that, upon implantation of the support, the at least one protrusion is positioned along the arterial portion in a region substantially opposite from the junction between the artery and the vein.
5. The external vascular support of claim 4 , wherein the at least one protrusion is located closer to a downstream side of the region than an upstream side of the region.
6. The external vascular support of claim 2 , wherein the at least one protrusion is located in the support junction portion such that, upon implantation of the support, the at least one protrusion:
is in apposition with an exterior wall of the vein-artery junction, and;
imposes a vessel rounding at the vein-artery junction at the acute angle of the junction between the vein and the artery.
7. The external vascular support of claim 6 , wherein the vessel rounding has a radius of curvature in the range of 0.25 mm to 4 mm.
8. The external vascular support of claim 7 , wherein the vessel rounding has a radius of curvature in the range of 0.5 mm to 2.5 mm.
9. The external vascular support of claim 2 , wherein said acute angle is in the range of 20 to 60 degrees.
10. The external vascular support of claim 1 , wherein the at least one protrusion is attachable at a desired location on the external vascular support.
11. The external vascular support of claim 1 , wherein the at least one protrusion is integral to the external vascular support.
12. The external vascular support of claim 1 , wherein the protrusion is expandable.
13. The external vascular support of claim 12 , wherein the size and/or shape of the protrusion is adjustable.
14. The external vascular support of claim 1 , wherein said venous portion is configured to embrace said vein, and has a truncated conical shape, with a smallest diameter adjacent said junction.
15. The external vascular support of claim 1 , wherein said junction is an end-to-side anastomosis of said artery and said vein.