Bifurcation stent and balloon assemblies

• US 8,118,861 B2
• Filed: 03/28/2007
• Issued: 02/21/2012
• Est. Priority Date: 03/28/2007
• Status: Expired due to Fees

• Current Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Original Assignee: Boston Scientific Scimed (Boston Scientific Corporation)
• Inventors: Hegg, Jens, Meyer, Michael P.
• Primary Examiner(s): Sweet, Thomas J
• Assistant Examiner(s): Swaminathan, Seema
• Application Number:
  US11/692,735
• Publication Number:
  US 20080243232A1
• Time in Patent Office: 1,791 Days
• Field of Search: 623/1.11, 623/1.15, 623/1.35, 623/1.36, 623/1.37, 623/1.16
• US Class Current: 623/1.35
• CPC Class Codes: A61F 2/856 Single tubular stent with a side portal passage
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2250/0039 differing in diameter
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body

Abstract

A bifurcated stent that is positionable adjacent to a branched body vessel. The stent includes a tapered middle portion with a side branch assembly for positioning within the deviating branch of a body vessel. The portion of the stent positioned within the first body vessel and the portion positioned within the main branch vessel have largely different sized diameters. The middle region tapers steeply to bridge this diameter differential. The tapered middle region also angles the side branch assembly which can easily be extended at an angle to the main body of the stent.

Claims

1. A bifurcated stent having an unexpanded state and an expanded state, the stent constructed of a plurality of interconnected strut members forming a plurality of expansion columns along a length of the stent, the stent comprising:

a generally tubular first body defining a first lumen, the first body having a side opening bounded by a perimeter, a distal region distal to the side opening and having a distal region diameter, a proximal region proximal to the side opening and having a proximal region diameter, and a medial region between the distal and proximal regions, wherein the medial region defines the side opening,

wherein the medial region comprises at least three axially spaced expansion columns, each expansion column has a plurality of undulations, a continuous length including the undulations, and a diameter, the at least three axially spaced expansion columns comprise a proximal most expansion column at a proximal end of the medial region, a distal most expansion column at a distal end of the medial region, and at least one intermediate expansion column therebetween, wherein the proximal most expansion column and the distal most expansion column have different maximum expansion capacities, wherein the continuous length of the proximal most expansion column of the medial region is greater than the continuous length of the at least one intermediate expansion column, and the continuous length of the at least one intermediate expansion column is greater than the continuous length of the distal most expansion column of the medial region;

wherein, in the expanded state, the proximal region diameter is greater than the distal region diameter, wherein the proximal region diameter and the distal region diameter differ in size by one magnitude selected from the inclusive range of 18% to 35%;

wherein the medial region has a tapering diameter transitioning from a maximum diameter equal to the proximal region diameter at a proximal end of the medial region to a minimum diameter equal to the distal region diameter size at a distal end of the medial region, and

a second body comprising at least two projecting members,

wherein, in the expanded state, at least one of the projecting members of the second body extends obliquely from the first body, and the projecting members define a second lumen therethrough, and the second lumen is in fluid communication with the first lumen.

2. The stent of claim 1 in which the first body comprises a plurality of interconnected strut members, and a plurality of cells defining open spaces in the first lumen between interconnected strut members, the interconnected members being connected by at least one connector, the cells being in fluid communication with the first lumen and having an area greater than that of the side opening.

3. The stent of claim 2 further comprising at least one therapeutic agent coating, the at least one therapeutic agent coating being positioned at one location selected from the group consisting of:

at least one connector, at least one stent member, at least one projecting member, the distal region, the proximal region, the medial region, the first stent body, the second stent body, and any combination thereof.

4. The stent of claim 1 in which there are four interconnected expansion columns in the medial region.

5. The stent of claim 1 in which at least a portion of the distal region and at least a portion of the proximal region have a common axis.

6. The stent of claim 1, wherein the projecting members commonly extend around an axis oblique to the generally tubular first body, each projecting member has an outermost tip at a location farthest from the generally tubular first body, each outermost tip is spaced such that an axis extending between any two outermost tips is substantially perpendicular to the axis oblique to the generally tubular first body.

7. The stent of claim 1, wherein the undulations of the expansion columns of the medial region have equal amplitudes.

8. The stent of claim 1, wherein each expansion column of the medial region has a ratio of continuous length to diameter, wherein the ratio for the proximal most expansion column of the medial region is equal to the ratio for the distal most expansion column of the medial region.

9. The stent of claim 1, wherein the proximal region has a greater expansion capacity than the distal region.

10. A bifurcated stent comprising:

a generally tubular first body defining a first lumen, the first body having a side opening bounded by a perimeter, a distal region distal to the side opening and having a diameter, a proximal region proximal to the side opening and having a diameter, and a medial region between the distal and proximal regions, wherein the medial region defines the side opening,

wherein the medial region comprises four axially spaced expansion columns,

wherein each expansion column of the medial region has a plurality of undulations, a continuous length including the undulations, and a diameter,

wherein, from a proximal end to a distal end of the medial region, the four axially spaced expansion columns of the medial region comprise a first expansion column, a second expansion column, a third expansion column, and a fourth expansion column, wherein the first expansion column and the fourth expansion column have different maximum expansion capacities, wherein the continuous length of the first expansion column is greater than the continuous length of the second expansion column, and the continuous length of the second expansion column is greater than the continuous length of the fourth expansion column of the medial region;

wherein the distal region diameter and proximal region diameter of the first body have different sizes, the proximal region diameter size being greater than the distal region diameter size, the medial region has a tapering diameter transitioning from a maximum diameter equal to the proximal region diameter size at a proximal end of the medial region to a minimum diameter equal to the distal region diameter size at a distal end of the medial region, and

a second body comprising at least two projecting members, wherein, in an expanded state, at least one of the projecting members of the second body extends obliquely from the first body, and the projecting members define a second lumen therethrough, and the second lumen is in fluid communication with the first lumen.

11. The stent of claim 10, wherein the continuous length of the second expansion column is greater than the continuous length of the third expansion column of the medial region, and the continuous length of the third expansion column of the medial region is greater than the continuous length of the fourth expansion column of the medial region.

12. The stent of claim 10, wherein each expansion column comprises a plurality of interconnected struts.

13. The stent of claim 10, wherein the undulations of the expansion columns of the medial region have equal amplitudes.

14. The stent of claim 10, wherein each expansion column of the medial region has a ratio of continuous length to diameter, wherein the ratio for the proximal most expansion column of the medial region is equal to the ratio for the distal most expansion column of the medial region.

15. The stent of claim 10, wherein the proximal region has a greater expansion capacity than the distal region.