ASYMMETRIC BIFURCATED CROWN
An expandable stent for percutaneous procedures comprises a tubular structure disposed about a longitudinal axis and a plurality of fingers. The plurality of fingers, upon expansion of the stent, extends from the tubular structure about a second longitudinal axis which is angularly offset from the first longitudinal axis. At least one of the plurality of fingers has a length that is greater than that of the other fingers.
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This Application is a continuation of application Ser. No. 12/025,390, filed on Feb. 4, 2008, which is a continuation of application Ser. No. 10/288,621, filed on Nov. 5, 2002, now U.S. Pat. No. 7,326,242.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCHNot Applicable
BACKGROUND OF THE INVENTIONStents, grafts, stent-grafts, vena cava filters and similar implantable medical devices, collectively referred to hereinafter as stents, are radially expandable endoprostheses which are typically intravascular implants capable of being implanted transluminally and enlarged radially after being introduced percutaneously. Stents may be implanted in a variety of body lumens or vessels such as within the vascular system, urinary tracts, bile ducts, fallopian tubes, coronary vessels, secondary vessels, etc. Stents may be used to reinforce body vessels and to prevent restenosis following angioplasty in the vascular system. They may be self-expanding, expanded by an internal radial force, such as when mounted on a balloon, or a combination of self-expanding and balloon expandable.
Within the vasculature it is not uncommon for stenoses to form at a vessel bifurcation. A bifurcation is an area of the vasculature or other portion of the body where a first (or parent) vessel is bifurcated into two or more tubular component vessels. Where a stenotic lesion or lesions form at such a bifurcation, the lesion(s) can affect only one of the vessels (i.e., either of the tubular component vessels or the parent vessel) two of the vessels, or all three vessels.
Many of the bifurcated stents that have been disclosed are deployed by two balloons. A first balloon expands the main section of the stent and a second balloon expands the branch.
In spite of the many bifurcated stents that have been disclosed, there remains a need for innovative bifurcated stents which may be deployed using a single balloon for the main section and an alternate mechanism for the side branch. There also remains a need for bifurcated stents with innovative designs in the region of the bifurcation to provide adequate coverage of the carina.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety. Without limiting the scope of the invention, a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided as well for the purposes of complying with 37 C.F.R. 1.72.
BRIEF SUMMARY OF THE INVENTIONIn one embodiment, the invention is directed to an expandable stent having a tubular structure which is disposed about a first longitudinal axis and a plurality of fingers which, upon expansion of the stent, extend from the tubular structure about a second longitudinal axis. The second longitudinal axis is angularly offset from the first longitudinal axis. At least one of the plurality of fingers has a length that is greater than that of the other fingers. In the unexpanded state the fingers may lie substantially on the surface of the stent.
Desirably, the fingers are disposed about an opening of the stent. The fingers and the opening define a crown.
Another embodiment of the invention is directed to a stent with a crown having fingers in which one portion of the crown has fingers that have a shorter average length than the average length of fingers on another portion of the crown.
Another embodiment of the invention is directed to a stent with a crown having fingers in which the proximal portion of the crown has fingers with a longer average length than the average length of fingers on the distal portion of the crown.
Another embodiment of the invention is directed to a stent with a crown having fingers in which the proximal portion of the crown has fingers with a shorter average length than the average length of fingers on the proximal portion of the crown.
Another embodiment of the invention is directed to a stent in an unexpanded condition with a crown. The fingers on a more distal portion of the crown extend proximally in such a way that a portion of at least one finger on the distal portion is proximal to a portion of at least one finger on the proximal portion of the crown which extend distally such that the fingers overlap one another. Another embodiment is directed to fingers that are interlaced with one another.
Another embodiment of the invention is directed to a stent with a crown having fingers with a length between 10.0 and 0.5 mm; desirably between 7.0 and 1.0 mm; and more desirably between 5.5 and 1.5 mm.
Another embodiment of the invention is directed to a stent with a crown having fingers in which the fingers have varying lengths.
Another embodiment is directed to a stent with a crown that begins opening into the secondary lumen before the main body of the stent is fully deployed.
A further embodiment of the invention is directed to a bifurcated stent comprising a first tubular component and a second tubular component. The first tubular component has a longitudinal axis, and the second tubular component has a longitudinal axis angularly offset relative to the first longitudinal axis. The second tubular component extends from the first tubular component. The second tubular component has a plurality of fingers with at least one of the plurality of fingers having a length that is greater than that of the other fingers.
Another embodiment is directed to a bifurcated stent having a tubular structure with a first longitudinal axis and fingers extending therefrom. The fingers are positioned about a second longitudinal axis wherein at least one finger is longer than an adjacent finger. Desirably, the fingers are disposed about an opening.
Another embodiment is directed to a catheter for delivery of a stent. The catheter comprises an apparatus for expanding a crown of the stent. The apparatus has a pushing device with a proximal end region and a distal end region. The proximal end region corresponds to a proximal end of a catheter, and the distal end region is constructed and arranged to be positioned adjacent to the stent to expand the crown members when the pushing device is advanced.
The pushing device may be a rod or hypotube.
In another embodiment, the catheter comprises a balloon, and the stent is disposed about a portion of the balloon. At least a portion of the distal end region of the pushing device is fixedly attached to the balloon at a region of attachment with the distal end of the pushing device having flexible spaced portions proximal to the region of attachment such that when a distal force is applied to the pushing device the spaced portions bend outwardly from the pushing device thereby engaging the crown members of the crown to expand the crown.
In another embodiment the catheter comprises a balloon, and the stent is disposed about a portion of the balloon. The distal end of the pushing device includes a two member cantilever mechanism. A first member extends substantially parallel to a longitudinal axis of the catheter, and a second member extends proximally at an oblique angle from a region of attachment at the distal end of the first member. The first member and the second member are fixedly attached one to the other at a joining region. The joining region is fixedly engaged to the balloon with the distal end region of the pushing device extending between the first member and the second member. When the pushing device is advanced, the second member rotatingly engages the plurality of crown members to expand the crown.
Another embodiment is directed to a catheter wherein the pushing device includes a ring portion. The ring has a first portion and a second portion. The first portion being positioned proximal to the distal end region, and the second portion is positioned distal to the distal end region of pushing device. The ring portion rotatingly engages the plurality of crown members to expand the crown.
Another embodiment is directed to a catheter wherein the pushing device includes a plurality of web-like strands. The plurality of web-like strands is constructed and arranged to engage the plurality of crown members when the pushing device is advanced in a distal direction to a first predetermined distance. When the pushing device is advanced to a second predetermined distance, the plurality of web-like strands pulls the crown members to expand the crown.
A detailed description of the invention is hereafter described with specific reference being made to the following drawings.
While this invention may be embodied in many different forms, there are described in detail herein specific embodiments of the invention. This description is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated.
As discussed above, the present invention is directed to a variety of bifurcated stents. The embodiments disclosed herein may be balloon expandable, self-expanding, or hybrid stents.
A first embodiment of the invention is depicted in
In one embodiment of the pushing device, as shown in
Another embodiment is illustrated in
In
The above disclosure is intended to be illustrative and not exhaustive. This description will suggest many variations and alternatives to one of ordinary skill in this art. All these alternatives and variations are intended to be included within the scope of the claims where the term “comprising” means “including, but not limited to”. Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the claims.
Further, the particular features presented in the dependent claims can be combined with each other in other manners within the scope of the invention such that the invention should be recognized as also specifically directed to other embodiments having any other possible combination of the features of the dependent claims. For instance, for purposes of claim publication, any dependent claim which follows should be taken as alternatively written in a multiple dependent form from all prior claims which possess all antecedents referenced in such dependent claim if such multiple dependent format is an accepted format within the jurisdiction (e.g. each claim depending directly from claim 1 should be alternatively taken as depending from all previous claims). In jurisdictions where multiple dependent claim formats are restricted, the following dependent claims should each be also taken as alternatively written in each singly dependent claim format which creates a dependency from a prior antecedent-possessing claim other than the specific claim listed in such dependent claim below.
Claims
1. A bifurcation stent having an unexpanded configuration and an expanded configuration, in the unexpanded configuration the bifurcation stent comprising:
- a main stent body comprising a bifurcation crown, the bifurcation crown comprising a first portion and a second portion; the first portion comprising a first plurality of fingers and the second portion comprising a second plurality of fingers, wherein the first plurality of fingers is opposed to the second plurality of fingers across the bifurcation crown and the first plurality of fingers has an average length that is greater than the average length of the second plurality of fingers.
2. The bifurcation stent of claim 1, wherein, in an unexpanded configuration, at least a majority of the first plurality of fingers and at least a majority of the second plurality of fingers extend in a longitudinal direction relative to the main body of the bifurcation stent.
3. The bifurcation stent of claim 1, wherein, in the unexpanded configuration, at least one of the first plurality of fingers overlaps at least one of the second plurality of fingers.
4. The bifurcation stent of claim 1, wherein, in the unexpanded configuration, at least one of the fingers of the first plurality of fingers is interlaced with at least one of the fingers of the second plurality of fingers.
5. The bifurcation stent of claim 1, wherein, in an unexpanded configuration, at least one of the fingers of the first plurality of fingers and at least one of the fingers of the second plurality of fingers extend at an oblique angle relative to the longitudinal direction of the main body of the bifurcation stent.
6. A stent comprising:
- a bifurcation crown comprising a distal portion and a proximal portion, the distal portion configured to engage the carina of a body lumen, the proximal portion configured to engage a portion of the body lumen contralateral to the carina,
- the distal portion comprising a plurality of distally extending fingers, the proximal portion comprising a plurality of proximally extending fingers, the plurality of distally extending fingers including a shortest finger and the plurality of proximally extending fingers including a longest finger, wherein the fingers between the shortest finger and the longest finger successively increase in length and the fingers between the longest finger and the shortest finger successively decrease in length.
7. The bifurcation stent of claim 6, wherein each of the fingers of the plurality of proximally extending fingers and the plurality of distally extending fingers is less than 5.5 mm in length.
8. The bifurcation stent of claim 6 further comprising an expanded configuration and an unexpanded configuration, wherein in the unexpanded configuration, at least one of the plurality of proximally extending fingers overlaps at least one of the distally extending fingers.
9. The bifurcation stent of claim 6, wherein the proximal portion comprises between five and twelve fingers and the distal portion comprises between five and twelve fingers.
10. The bifurcation stent of claim 6, further comprising an unexpanded configuration and an expanded configuration, wherein in the expanded configuration, each of the fingers of the plurality of distally extending fingers and plurality of proximally extending fingers extend along a secondary lumen and terminate along a common plane that is orthogonal to the secondary lumen.
11. A bifurcation stent have an unexpanded configuration and an expanded configuration, the bifurcation stent comprising:
- a primary tubular body having a side branch opening, the side branch opening defining a bifurcation crown, the bifurcation crown having a proximal portion and a distal portion, each of the proximal and distal portions having a plurality of fingers that extend at least partially across the side branch opening when the bifurcation stent is in the unexpanded configuration, the fingers of the plurality of fingers of the proximal portion being generally disposed opposite to fingers of the fingers of the distal portion, wherein the branch opening is asymmetric such that the fingers of the proximal portion extend further across the side branch opening than the opposing fingers of the distal portion.
12. The bifurcation stent of claim 11, wherein at least one of the plurality of fingers of the proximal portion overlaps at least one of the opposing fingers of the distal portion.
13. The bifurcation stent of claim 11, wherein, in the expanded configuration, each of the plurality of fingers of the proximal portion and each of the plurality of fingers of the distal portion extend along a secondary lumen and terminate along a common plane that is orthogonal to the secondary lumen.
14. The bifurcation stent of claim 11, wherein the plurality of fingers of the proximal portion comprises between five and twelve fingers and the plurality of fingers of the distal portion comprises between five and twelve fingers.
15. The bifurcation stent of claim 14, wherein the bifurcation stent is balloon expandable.
Type: Application
Filed: Sep 15, 2009
Publication Date: Jan 7, 2010
Applicant: Boston Scientific Scimed, Inc. (Maple Grove, MN)
Inventor: Tracee Eidenschink (Wayzata, MN)
Application Number: 12/559,910