Device and method for compartmental vessel treatment
An angioplasty balloon having an elastic constraining structure that partially expands with the balloon so that, at maximum balloon inflation, the constraining structure forms a pattern of channels or “pillows” on the balloon.
1. A balloon catheter comprising:
a catheter shaft;
a balloon on the catheter shaft; and
a constraining structure disposed over the balloon, the constraining structure comprising a plurality of discrete circumferentially spaced-apart axial struts crossing a plurality of discrete, axially spaced-apart radially expandable rings, the plurality of rings comprising a distal ring, a proximal ring, and an intermediate ring therebetween;
wherein the constraining structure is configured to transition between an unexpanded configuration and an expanded configuration;
wherein each axial strut of the constraining structure is fixedly attached to the catheter on a distal side of the balloon and/or a proximal side of the balloon in both the unexpanded configuration and the expanded configuration to prevent detachment of the constraining structure from the catheter shaft; and
wherein inflation of the balloon expands the constraining structure to the expanded configuration with a plurality of isolated balloon regions protruding from openings between the plurality of circumferentially spaced-apart axial struts crossing the plurality of axially spaced-apart radially expandable rings, the plurality of isolated balloon regions configured to contact a wall of the blood vessel with the constraining structure displaced from the wall of the blood vessel.
2. The balloon catheter of claim 1 , wherein at least one of a distal end of each axial strut and a proximal end of each axial strut can translate axially over said the catheter shaft as said balloon is inflated.
3. The balloon catheter of claim 1 , wherein said axial struts are configured to elongate as said balloon is inflated.
4. The balloon catheter of claim 1 , wherein both ends of said constraining structure are fixedly attached to the catheter shaft.
5. The balloon catheter of claim 1 , wherein the constraining structure comprises an elastic material.
6. The balloon catheter of claim 1 , wherein each of said radially expandable rings comprises a deformable feature configured to permit radial expansion of said radially expandable rings when said balloon is inflated.
7. The balloon catheter of claim 6 , wherein the deformable feature comprises a zig-zag.
8. The balloon catheter of claim 6 , wherein the deformable feature comprises an S-curve.
9. The balloon catheter of claim 6 , wherein the deformable feature comprises a coil.
10. The balloon catheter of claim 1 , wherein said balloon is coated with a drug.
11. The balloon catheter of claim 1 , wherein the plurality of axial struts overlap the plurality of radially expandable rings.
12. The balloon catheter of claim 1 , wherein when inflated, the balloon comprises a tapered proximal portion, a tapered distal portion, and a central portion therebetween, and wherein the plurality of radially expandable rings are disposed over the central portion of the balloon.