U.S. patent application number 12/242196 was filed with the patent office on 2009-04-16 for elongate flexible torque instruments and methods of use.
Invention is credited to Brian Beckey, David C. Forster, Scott Heneveld, Alex T. Roth, Brandon G. Walsh.
Application Number | 20090099554 12/242196 |
Document ID | / |
Family ID | 38834303 |
Filed Date | 2009-04-16 |
United States Patent
Application |
20090099554 |
Kind Code |
A1 |
Forster; David C. ; et
al. |
April 16, 2009 |
Elongate Flexible Torque Instruments And Methods Of Use
Abstract
Torque shafts and other related systems and methods are
described herein. In one embodiment, the torque shafts are both
flexible and capable of transmitting torque. An apparatus for
transmission of torque includes an elongate body, comprising a
plurality of joint segments, each joint segment configured to pivot
with respect to an adjacent segment and being further configured to
have at least two link elements.
Inventors: |
Forster; David C.; (Los
Altos Hills, CA) ; Roth; Alex T.; (Redwood City,
CA) ; Beckey; Brian; (Woodside, CA) ; Walsh;
Brandon G.; (Syracuse, UT) ; Heneveld; Scott;
(Whitmore, CA) |
Correspondence
Address: |
ORRICK, HERRINGTON & SUTCLIFFE, LLP;IP PROSECUTION DEPARTMENT
4 PARK PLAZA, SUITE 1600
IRVINE
CA
92614-2558
US
|
Family ID: |
38834303 |
Appl. No.: |
12/242196 |
Filed: |
September 30, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/US2007/071535 |
Jun 19, 2007 |
|
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12242196 |
|
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60805334 |
Jun 20, 2006 |
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Current U.S.
Class: |
606/1 |
Current CPC
Class: |
F16C 2226/78 20130101;
F16C 2316/10 20130101; Y10T 403/7073 20150115; A61M 25/0138
20130101; F16C 1/04 20130101; A61M 25/0043 20130101; A61F 2/2427
20130101; A61M 25/0147 20130101; Y10T 403/70 20150115; Y10T
403/7045 20150115; A61M 25/0113 20130101 |
Class at
Publication: |
606/1 |
International
Class: |
A61B 17/00 20060101
A61B017/00 |
Claims
1. An apparatus for transmission of torque, comprising: a plurality
of segments coupled together in an elongate configuration, wherein
each segment comprises: a first end comprising a male feature; and
a second end comprising a female feature, the female feature having
a shape corresponding to the male feature such that the female
feature is configured to receive the male feature of the first end
of an adjacent segment.
2. The apparatus of claim 1, wherein the male feature has a "T"
like shape.
3. The apparatus of claim 1, wherein the male feature has a
teardrop shape.
4. The apparatus of claim 1, wherein the male feature is configured
to interlock with the female feature.
5. The apparatus of claim 1, wherein the male feature is a first
male feature and the female feature is a first female feature, each
segment comprising: a second male feature on the first end, the
second male feature being configured differently from the first
male feature; and a second female feature on the second end, the
second female feature being configured differently from the first
female feature, the second female feature having a shape
corresponding to the second male feature such that the second
female feature is configured to receive the second male feature of
the first end of an adjacent rigid segment.
6. The apparatus of claim 1, further comprising a segment having a
second end that does not have a female feature.
7. The apparatus of claim 1, further comprising a segment having a
first end that does not have a male feature.
8. The apparatus of claim 1, wherein a first segment of the
plurality of segments is pivotable with respect to an adjacent
second segment of the plurality of segments.
9. The apparatus of claim 8, wherein the female feature of the
second segment is configured to rotate about the male feature of
the first segment.
10. The apparatus of claim 9, wherein each segment comprises a
pivot space, the pivot space is adjacent at least one of the male
and female features, the female feature is a first female feature,
the male feature is a first male feature, and the pivot space is a
first pivot space, each segment further comprising: a second male
feature located opposite the first male feature and having the same
configuration as the first male feature; a second female feature
located opposite the first female feature and having the same
configuration as the first female feature; and a second pivot space
located opposite the first pivot space and having the same
configuration as the first pivot space.
11. The apparatus of claim 8, wherein the first segment is coupled
to the second segment by a hinge.
12. The apparatus of claim 11, wherein the hinge is a living hinge,
the male feature is configured to slide within the female feature,
each segment further comprises a pivot space and at least one of
the male or female features is located in at least one of the pivot
spaces of the segments, and the living hinge is a first living
hinge, the female feature is a first female feature, the male
feature is a first male feature, and the pivot space is a first
pivot space, each segment further comprising: a second living hinge
located opposite the first living hinge and having a similar
configuration to the first living hinge; a second male feature
located opposite the first male feature and having a similar
configuration to the first male feature; a second female feature
located opposite the first female feature and having a similar
configuration to the first female feature; and a second pivot space
located opposite the first pivot space.
13. A medical apparatus, comprising: a tubular member configured to
interface with a prosthesis; a torque drive coupled with the
tubular member and configured to rotate the tubular member, the
torque drive being configured to fit within the vasculature of a
patient.
14. The medical apparatus of claim 13, wherein the tubular member
is a torque shaft.
15. The medical apparatus of claim 14, further comprising a cable
configured to interface with the torque drive.
16. The medical apparatus of claim 15, wherein the torque drive is
configured to translate axial motion of the cable into rotational
motion of the torque shaft, wherein the torque shaft comprises: a
sheave; and a cable hub rotatably coupled to the sheave and fixably
coupled with the torque shaft, the cable hub configured to receive
the cable in a wrapped state.
17. An elongate flexible torque instrument for deploying implants,
comprising: an elongate body comprising a plurality of flexible
torque members, wherein each torque member is comprised of
segments, the segments being configured to pivot with respect to an
adjacent segment, and each torque member is configured to transmit
torque from a proximal portion to a distal portion of the torque
member; a handle operatively coupled to the proximal end of each of
the flexible torque members; wherein the handle comprises a control
lever configured to operate one or more control wires to steer the
elongate flexible body and a plurality of control knobs configured
to apply torque to the flexible torque members to transmit torque
from proximal portions of the flexible torque members to distal
portions of the flexible torque members; and an implant deployment
apparatus operatively coupled to the distal ends of the flexible
torque members, wherein the implant deployment apparatus is
configured to deploy an implant with torque transmitted to the
flexible torque members.
18. The elongate flexible torque instrument of claim 17, wherein
each segment is coupled to an adjacent segment by a link
element.
19. The elongate flexible torque instrument of claim 17, wherein
the segments are pivoted about a link element.
20. The elongate flexible torque instrument of claim 18, wherein
the link element is a physical link element, a pivotal link
element, or a torque link element.
21. The elongate flexible torque instrument of claim 17, wherein
each segment is coupled to an adjacent segment by a combination of
a physical link element and a torque link element or a pivotal link
element and a torque link element.
22. The elongate flexible torque instrument of claim 21, wherein
the physical link element is disposed about 90 degrees from the
torque link element or the pivotal link element is disposed about
90 degrees from the torque link element.
23. The elongate flexible torque instrument of claim 17, wherein
the flexible torque members are configured to apply counter-acting
torque, counter-rotating, or opposing torque to the implant
deployment apparatus to deploy an implant.
24. The elongate flexible torque instrument of claim 20, wherein
the physical link element comprises one or more struts and one or
more spaces between the one or more struts.
25. The elongate flexible torque instrument of claim 20, wherein
the torque link element comprises a male element and a female
element, and wherein the female element of one segment is
configured to receive the male element of an adjacent segment.
26. The elongate flexible torque instrument of claim 17, wherein
the segment are cut at an angle in the range between about 0 degree
and about 90 degrees.
27. The elongate flexible torque instrument of claim 17, wherein
the flexible torque member includes a flexible membrane sheath to
maintain the segments together.
28. A method for deploying an implant inside a body of a patient,
comprising: inserting a distal portion of an elongate flexible
torque instrument into a patient, the elongate flexible torque
instrument comprising a plurality of flexible torque members, each
flexible torque member comprising a plurality of segments;
advancing and navigating the distal portion of the elongate
flexible torque instrument through natural pathways inside the
patient to a target site; applying torque to a proximal portion of
the elongate flexible torque instrument; and transmitting the
applied torque from the proximal portion to the distal portion of
the elongate flexible torque instrument to operate an implant
deployment apparatus, wherein the transmitted torque facilitates
deployment of an implant from the implant deployment apparatus to
the target site.
29. The method for deploying an implant inside a body of a patient
of claim 28, wherein counter-acting torque, counter-rotating
torque, or opposing torque is applied to operate the implant
deployment apparatus.
30. An apparatus for transmitting torque, comprising: an elongate
body, the elongate body comprising a plurality of segments, each
segment configured to pivot with respect to an adjacent segment and
being further configured to have a pair of link elements, each link
element having a hub and a plurality of physical link elements
extending from said hub and coupled with a rim of an adjacent
segment.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part of PCT
Application Serial No. PCT/US2007/071535, titled "Torque Shaft and
Torque Drive", filed on Jun. 19, 2007, which claims priority to
U.S. Provisional Application Ser. No. 60/805,334, titled "Torque
Shaft and Torque Drive", filed on Jun. 20, 2006, each of which is
incorporated herein by reference in its entirety for all
purposes.
BACKGROUND OF THE INVENTION
[0002] 1. Field
[0003] Embodiments of the present invention relate generally to
elongate flexible instruments, and more particularly, to the
manufacture and use of such elongate flexible instruments, which
may be configured to be extension tools for a variety deployment,
placement, installation, maintenance, repair, or removal type of
functions, procedures, operations, or applications.
[0004] 2. Background
[0005] Typical elongate flexible instruments may be comprised of
flexible shafts, tubes, rods, etc., which may be susceptible to
torque deflection or torque lag to the extent that rotation of one
end of the instrument may not correlate closely to rotation of the
opposite end of the instrument and substantial amount of wind-up or
excessive amount of initial rotation or torque may be required at
the outset before correlatable rotation or torque transmission
could be achieved. In addition, elongate flexible instruments may
be susceptible to buckling and/or kinking such that reliable torque
transmission may be for practical purposes virtually impossible.
Accordingly, there is a need for an elongate flexible instrument
that allows improved transmission of rotation or torque.
BRIEF SUMMARY OF THE INVENTION
[0006] Various embodiments of an apparatus for transmission of
torque are disclosed herein. In one variation, an apparatus for
transmission of torque includes an elongate body, wherein said
elongate body is comprised of a plurality of segments; each segment
may be configured to flex or pivot with respect to an adjacent
segment and each segment may include at least two link
elements.
[0007] In one example, an apparatus for transmitting torque
includes a plurality of joined segments in an axial arrangement,
wherein each of said segments may be linked or joined to an
adjacent segment by a living link element and the segments may be
configured to flex or pivot about said living link element.
[0008] In another example, an apparatus for transmitting torque
includes an elongate body, wherein said elongate body may be
comprised of a plurality of joined segments. Each segment may be
configured to flex or pivot with respect to an adjacent segment and
each segment may be configured to have a pair of link elements.
Each link element may include a hub and a plurality of living link
elements extending from said hub that may be coupled to a rim of an
adjacent segment.
[0009] An exemplary embodiment of a method for operating an
apparatus for transmitting torque is disclosed, which may be
applicable to any or all of the apparatuses as described in
accordance with embodiments of the present invention disclosed
herein. The method may include attaching a medical prosthesis at a
distal end of said torque transmitting apparatus, inserting said
prosthesis into a patient's vasculature, navigating within said
patient's vasculature, and deploying said medical prosthesis at a
target region.
[0010] Other systems, methods, features, and advantages of the
present invention will be apparent to one of ordinary skill in the
art upon examination of the following figures and detailed
description. It is intended that all such additional systems,
methods, features, and advantages be within the scope of the
present invention. It is also intended that the present invention
is not limited to the specific details of the exemplary
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] The details of the invention, both as to its structure and
operation, may be gleaned in part by study of the accompanying
figures, in which like reference numerals refer to like parts. The
components in the figures are not necessarily drawn to scale;
instead emphasis is placed upon illustrating the principles of the
invention. Moreover, all illustrations are intended to convey
concepts, where relative sizes, shapes and other detailed
attributes may be illustrated schematically rather than literally
or precisely.
[0012] FIG. 1 illustrates an elongate flexible torque instrument in
accordance with one embodiment of the present invention.
[0013] FIG. 2A illustrates a portion of a flexible torque member in
accordance with one embodiment of the present invention.
[0014] FIG. 2B illustrates a portion of a flexible torque member in
accordance with one embodiment of the present invention.
[0015] FIG. 3 illustrates a portion of another flexible torque
member in accordance with one embodiment of the present
invention.
[0016] FIG. 4 illustrates the interface of physical link element or
splink link element and torque link element or torque finger
element for one exemplary embodiment of torque shaft (400) in a
planar depiction.
[0017] FIG. 5 depicts a torque shaft with splink link and torque
finger interlocking elements according to another embodiment.
[0018] FIG. 6A illustrates a side view of a torque shaft with a
wagon wheel link element according to another embodiment of the
present invention.
[0019] FIG. 6B illustrates an isometric view of the same torque
shaft.
[0020] FIG. 7 illustrates one example of an interface or
implementation of flexible torque members with an implant
deployment apparatus in accordance with one embodiment of the
present invention.
[0021] FIGS. 8A-8C show a torque shaft with T-shaped interlocking
features according to an embodiment.
[0022] FIGS. 9A-9B show a torque shaft with teardrop shaped
interlocking features according to another embodiment.
[0023] FIG. 10 illustrates the torque transferring capability of
the torque shaft.
[0024] FIG. 11 shows a torque shaft with spiral slots running the
length of the torque shaft.
[0025] FIGS. 12-13 show a spot-link torque shaft according to
another embodiment.
[0026] FIG. 14 shows a torque shaft with living hinges according to
another embodiment.
[0027] FIGS. 15-16 show two opposing torque shafts according to
another embodiment.
[0028] FIG. 17 shows a pull-pull torque drive according to another
embodiment.
[0029] FIG. 18 shows a device for translating axial force applied
to the shaft into rotational movement of the shaft.
[0030] FIG. 19A illustrates an example of an elongate flexible
torque instrument being used to deliver an implant to a target site
inside a patient in accordance with one embodiment of the present
invention.
[0031] FIG. 19B illustrates an example elongate flexible torque
instrument being used in an antegrade approach to deliver an
implant to a target site inside a patient.
[0032] FIG. 19C illustrates a process flowchart for using the
elongate flexible torque instrument to deliver and deploy an
implant in accordance with one embodiment of the present
invention.
[0033] FIG. 19D illustrates an example elongate flexible torque
instrument being used in a retrograde approach to deliver an
implant to a target site inside a patient.
DETAILED DESCRIPTION
[0034] Elongate flexible torque instruments and methods for their
use and manufacture are described herein. The elongate flexible
torque instruments in accordance with embodiments of the present
invention may be both flexible and stiff at the same time. In one
embodiment, the elongate flexible torque instruments according to
the present invention are designed and manufactured to be
substantially flexible for pivoting, steering, bending, etc., but
substantially stiff in resisting rotation and axial compression or
extension such that they may effectively transmit rotation or
torque and axial forces, loads, movements, etc., while it may be
pushed, pulled, advanced, retracted, navigated, steered, bent,
twisted, or contorted into various positions, shapes, orientations,
and/or tight curvatures along tortuous pathways. The functional
characteristics of the elongate flexible torque instruments as
described herein are particularly suited as extension tools for
deployment, placement, installation, maintenance, repair, or
removal type of functions, procedures, operations, or applications.
In particular, the elongate flexible torque instruments may be well
suited as extension tools for performing various minimally invasive
surgical procedures, e.g., deploying, placing, installing, or
removing implants (e.g., prosthetic heart valves) inside a patient.
For example, in a minimally invasive surgical procedure an implant
may be delivered to a target site in a patient through a
percutaneous incision or natural body orifice using one or more
elongate flexible torque instruments by way of the patient's
vasculature or natural body pathways (such vasculature and natural
body pathways may be tortuous and less than 1 cm in diameter) to
various organs (e.g., heart, stomach, bladder, uterus, etc.), or
tissue structures.
[0035] FIG. 1 illustrates an elongate flexible torque instrument in
accordance with one embodiment of the present invention, which may
be used as an extension tool to deliver an implant in minimally
invasive surgical procedures. As illustrated in FIG. 1, the
elongate flexible torque instrument (100) includes an elongate body
(102) that may be manually pushed, advanced, steered, and/or
rotated. The elongate body (102) may have an outer diameter in the
range of about 1.5 French to about 30 French--in the French
catheter scale. In some embodiments, the elongate body (102) may
have an outer diameter in the range of about 20 French to about 30
French. In other embodiments, the elongate body (102) may have an
outer diameter in the range of about 10 French to about 20 French.
In certain applications, the elongate body (102) may have an outer
diameter of about 11 French or about 12 French. In certain other
applications, the elongate body (102) may have an outer diameter of
about 9 French, about 8 French, about 7 French, or about 6
French.
[0036] Handle (104) includes a control lever (106) that may operate
one or more control wires or pull wires to steer the distal portion
of the elongate body (102) as the elongate body is pushed or
advanced through various tortuous natural body pathways. The use of
control wires or pull wires to steer an elongate body has been
previous described in various systems (e.g., a sheath member or a
guide member of a manually steerable catheter). Examples of such
steerable systems are disclosed U.S. patent application Ser. No.
11/073,363, titled "Robotic Catheter System", filed on Mar. 4,
2005; and U.S. patent application Ser. No. 11/481,433, titled
"Robotic Catheter System and Methods", filed on Jul. 3, 2006. In
addition, a first control knob (108) and a second control knob
(110) may be manually operated to rotate elements or components of
the elongate body (102), such that rotation or torque applied at
the first control knob (108) and/or second control knob (110),
either separately or in concert, transmits rotation or torque from
the proximal portion of the elongate body (102) to the distal
portion of the elongate body (102).
[0037] The elongate body (102) and elements of the elongate body
(102) may be designed and manufactured to be substantially stiff
for torsional applications, such that there is minimum amount of
torque deflection or torque lag from one section (e.g., the
proximal section) of the elongate body or elements of the elongate
body to another section (e.g., the distal section) of the elongate
body or elements of the elongate body. At the same time, the
elongate body (102) or elements of the elongate body (102) may also
be designed and manufactured to be substantially flexible, so that
the elongate body (102) may be steered, pivoted, or deflected in
various directions (e.g., up, down, pitch, yaw, etc.) as well as
bent or displaced into various positions, shapes, and/or tight
curvatures (e.g., a J-bend or a J-shaped bend). In addition, for
certain applications the elongate body (102) may be able to
neutrally maintain complex shapes and tight curvatures. For
example, no particular control or force may be necessary to
maintain the elongate body (102) in certain complex shapes or tight
curvatures. As will be explained in further detail, the elongate
body (102) is comprised of segments that are substantially free to
flex, bend, or pivot, such that that is no substantial resistance,
inertia, or inherent shape memory properties to return or restore
the elongate body (102) to a certain disposition, orientation, or
shape.
[0038] In addition, the elongate body (102) may be operatively
coupled to a delivery mechanism (112) to deliver an implant, such
as a prosthetic heart valve. The delivery mechanism (112) may be
similar to the deployment mechanism described in U.S. patent
application Ser. No. 11/364,715, titled "Methods And Devices For
Delivery Of Prosthetic Heart Valves And Other Prosthetics", filed
on Feb. 27, 2006; and U.S. patent application Ser. No. 11/364,724,
titled "Methods And Devices For Delivery Of Prosthetic Heart Valves
And Other Prosthetics", filed on Feb. 27, 2006, which are both
incorporated herein by reference in their entirety for all
purposes. The elongate flexible torque instrument (100) along with
the delivery mechanism (112) or similar delivery mechanisms (such
as those described in the aforementioned patent applications) may
be used to deliver an implant, such as a prosthetic heart valve,
which may be similar to those described in U.S. patent application
Ser. No. 11/066,124, titled "Prosthetic Heart Valves, Scaffolding
Structures, And Systems and Methods For Implantation of Same",
filed on Feb. 25, 2005; U.S. patent application Ser. No.
11/066,126, titled "Prosthetic Heart Valves, Scaffolding
Structures, And Systems and Methods For Implantation of Same",
filed on Feb. 25, 2005; and U.S. patent application Ser. No.
11/067,330, titled "Prosthetic Heart Valves, Scaffolding
Structures, And Systems and Methods For Implantation of Same",
filed on Feb. 25, 2005; these patent applications are all
incorporated herein by reference in their entirety for all
purposes.
[0039] FIG. 2A illustrates a portion or section of an elongate
flexible torque member (200) in accordance with one embodiment of
the present invention, which may be one of the elements or
components of the elongate body (102). The flexible torque member
(200) may be fabricated from a tube or shaft made from any suitable
material for the function, procedure, operation, or application for
which the elongate flexible torque instrument may be used. As one
of ordinary skill in the art having the benefit of this disclosure
will appreciate, the flexible torque member (200) may be fabricated
from a rod or other elongate structure other than a tube or shaft.
Accordingly, in some embodiments, the flexible torque member (200)
may include a lumen; while in some other embodiments, the flexible
torque member (200) may not include a lumen. For some embodiments,
the elongate flexible torque instrument (100) may be used for
minimally invasive surgical procedures; as such the flexible torque
member (200) may be fabricated from a tube, shaft, rod, or other
elongate structure made of any biologically compatible material,
e.g., stainless steel, Nitinol, other alloy or non-alloy material.
The fabrication process may include cutting the tube, shaft, rod,
or other elongate structure into a plurality of segment members;
such as first segment members (202a) and second segment members
(202b), as illustrated in FIG. 2A.
[0040] In addition, various elements, features, or patterns may be
cut into the segment members, such that the finished flexible
torque member (200) comprised of the segment members (202a and
202b) may be both substantially flexible (e.g., flexible for
steering movements or deflection, such as up, down, pitch, yaw,
etc.) and substantially stiff (e.g., stiff for torsion, twist, and
axial extension and compression, etc.). The plurality of segment
members (202a and 202b) of the flexible torque member (200) may be
physically linked. That is, as illustrated in this example, the
segment members (202a and 202b) may not be completely
circumferentially cut into separate or individual pieces or
segments; instead they may be physically linked together (for
example by a live link or living link (204c), as illustrated by the
material between the first link element (204a) and second link
element (204b)) as a one piece unit. In other embodiments of the
present invention, however, the segment members (202a and 202b) may
be completely circumferentially cut into separate or individual
pieces or segments. For those segments (202a and 202b) that are
completely circumferentially cut into separate or individual
pieces, they may be linked or joined together by fitting or
interlocking the separate or individual segments (202a and 202b)
together; similar to fitting or interlocking pieces of puzzles
together. The separate or individual segments (202a and 202b) may
be fitted together by way of the elements, features, or patterns
that may have been cut into one or more pivotal link elements (not
shown) of the segment members; similar to the physical link
elements but completely circumferentially cut.
[0041] FIG. 2A illustrates one embodiment of elements, features, or
patterns that may be cut into the segment members (202a and 202b).
As may be appreciated, the geometries of the elements, features, or
patterns may be any shape and/or size that would facilitate the
fitting or interlocking the first and second segments (202a and
202b). The linking, fitting, or joining of the separate and
individual first and second pieces or segments (202a and 202b) may
be further facilitated or made more secured by having the mating
segments cut at various angles (.alpha.), as illustrated in FIG.
2B, so that the segments (202a and 202b) may be fitted or
interlocked together more securely to reduce the chances for the
segments (202a and 202b) to separate or the flexible torque member
(200) falling apart into pieces of segments (202a and 202b).
[0042] In some embodiments, the segments may be cut at cut angle in
range between about 0 degree and about 90 degrees substantially
about the periphery of the features of the segments. In some
particular embodiments, the segments may be cut at cut angle
(.alpha.) in the range between about 0 degree and about 30 degrees
substantially about the periphery of the features of the segments.
In other embodiments, the segments may be cut at cut angle
(.alpha.) in the range between about 30 degrees and about 45
degrees substantially about the periphery of the features of the
segments. In other particular embodiments, the segments may be cut
at cut angle (.alpha.) in the range between about 45 degrees and
about 60 degrees substantially about the periphery of the features
of the segments. In further particular embodiments, the segments
may be cut at cut angle (.alpha.) in the range between about 60
degrees and about 90 degrees substantially about the periphery of
the features of the segments.
[0043] In some embodiments, the flexible torque member (200) may be
encapsulated by a flexible membrane sheath to maintain the
individual and separate pieces of segments together. The flexible
torque member (200) may be made from a tube, shaft, rod, or other
elongate structure, which may be cut by moving and turning the
tube, shaft, rod, or other elongate structure across a cutting tool
to cut out the mating or interlocking segments (202a and 202b) as
well as the particular elements, features, or patterns that may
help the segments (202a and 202b) fit, mate, or interlock together.
The cutting tool may be manually controlled or computer controlled
(e.g., a computer controlled laser cutting tool) cutting system. In
addition, the segments (202a and 202b) as well as the particular
elements, features, or patterns may be cut at prescribed cut angles
(.alpha.) as discussed to further provide secure fitting or
interlocking of the segments (202a and 202b) into one unit making
up the flexible torque member (200). The cutting process may remove
a portion of the tube, shaft, rod, or other elongate structure so
as to leave open spaces or gaps between first and second segments
(202a and 202b). The width of these spaces or gaps may be
substantially large enough to allow adjacent segments (202a and
202b) to move, flex, pivot, or bend at various angles relative to
each other. For example, the larger the space or gap between the
first and second segments (202a and 202b), the greater the relative
movement, flex, pivot, or bend may be possible between adjacent
segments (202a and 202b).
[0044] Still referring to FIG. 2A, first and second segments (202a
and 202b) of the flexible torque member (200) include mating or
interlocking geometries of physical link elements (204a and 204b)
and torque link elements (206a and 206b). In this example, physical
link elements (204a and 204b) include live link or living link
elements (204c) in which the first and second segments (202a and
202b) are physically linked together, such that the flexible torque
member (200) is one continuously and physically linked member. In
other embodiments, the physical link elements (204a and 204b) may
not include a live link or living link element, such that the
flexible torque member (200) is not one continuously and physically
linked member. Instead, the flexible torque member (200) is
comprised of fitted or interlocked separate and individual segments
(202a and 202b). The physical link elements (204a and 204b) allow
the segments (202a and 202b) to flex, pivot, or bend relative to
each other, such that the flexible torque member (200) may be
steered in various directions or displacements, e.g., up, down,
sideways, pitch, yaw, etc. In addition, the torque link elements
(206a and 206b) includes torque fingers (206c) that may provide
torsional or rotational support or rigidity to the fitted, mated,
contacted, or interlocked segments (202a and 202b), such that the
flexible torque member (200) is flexible, e.g., up, down, sideways,
pitch, yaw, etc., but also torsionally stiff against rotation,
twist, torque, etc.
[0045] FIG. 3 illustrates a portion or section of another flexible
torque member (300), in accordance with one embodiment of the
present invention, including one embodiment of a physical link
element (304) and one embodiment of torque link element (306). The
flexibility of the flexible torque member (300) per unit length may
be dependent upon the amount of flex, bend, or pivot between
adjacent segments (302a, 302b, 302c, etc.) relative to each other.
Since the amount that adjacent segments (302a, 302b, 302c, etc.)
may be able to flex, bend, or pivot may be determined by the space
or gap between the segments, e.g., space or gap (410) illustrated
in FIG. 4, the overall flexibility of the torque member (300) per
unit length may be determined or characterized by the width of the
space or gap (410) and the number of segments (302a, 302b, 302c,
etc.) per unit length.
[0046] The physical link element (304) and torque link element
(306) allow the flexible torque member (300) to be flexible while
enabling the torque member (300) the ability to transmit torque
that is applied at one end of the torque member (300) to the other
end of the torque member (300). As the flexible torque member (300)
is rotated about its longitudinal axis, as illustrated in FIG. 3 by
the directions indicated by the arrow, the link elements (304 and
306) may transfer or transmit torsional force longitudinally along
the length of the torque member (200), at which point torque may be
transferred or transmitted between the adjacent segments (302a,
302b, 302c, etc.) along the length of the flexible torque member
(300).
[0047] Looking more closely at FIG. 3, each physical link element
(304) may include two strut elements (310) that may substantially
surround a living link element (308). A living link element (308)
may be considered as an element that provides a physical link
between two member components. In this example, the living link
element (308) provides a physical link between a first segment
(302a) and a second segment (302b). Similarly, the living link
element (308) also provides a physical link between a second
segment (302b) and a third segment (302c). Such physical linkages
may continue on with many segments of a flexible torque member. The
strut elements (310) may have circular shapes or any suitable
geometrical shapes and may be configured to pivot within a space,
gap, or slot (312), which may have corresponding or mating shapes
to the strut element (310) for receiving, matching, mating with the
strut elements (310), so that adjacent segment (e.g., 302a and 302b
or 302b and 302c) may flex, bend, pivot, etc. relative to one
another. This combination of physical link elements or
configuration may be referred to as a splink link element since it
is composed of the combination of a spot link and a living link (as
described in full in PCT Application Serial No. PCT/US2007/071535).
Accordingly, in this example, a splink element or splink link
element (304) may be collectively comprises a living link element
(308), strut elements (310), the space, gap, or slot (312) between
adjacent segment members (302a, 302b, 302c, etc.) of a flexible
torque member (300).
[0048] Still referring to FIG. 3, each segment (302a, 302b, 302c,
etc.) may also include torque link elements (306). A torque link
element (306) may include a male element (314) and a female element
(16). As illustrated in FIG. 3, a male element (314) of one segment
member (e.g., 302a) mates with or fits into a female element (316)
of an adjacent segment member (e.g., 302b). The combination of
mating or fitting of the male element (314) into the female element
(316) in no way affects the flexing, bending, or pivoting or
adjacent segments (e.g., between segment 302a and 302b, and between
segment 302b and segment 302c, etc.) as allowed by the physical
link element (304). The amount of flex, bend, or pivot between two
adjacent segment members is defined or characterized by the amount
of space or gap (e.g., space or gap (402)) between the adjacent
members as previously described. Each female element 316 preferably
receives the male element 314 in relative or substantial tight
confines so as to allow movement in an axial direction but not
rotational, although minimal rotational movement may occur. The
described torque link 306 may be referred collectively as torque
finger element 306.
[0049] Referring again to FIG. 3, in some embodiments to increase
the flexibility of the torque member (300), the physical link
elements (304) or splink link elements (304) and the torque link
elements (306) or torque finger elements (306) may be oriented or
disposed at about 90 degrees with respect to each other. This may
be done to enable the interlocking or link elements 304 and 306 to
hold or support the segments (e.g., 302a, 302b, and 302c) together;
such that the flex, bend, or pivot axes of the segments (302a,
302b, and 302c) may be alternated between two perpendicular axes.
For example, as illustrated in FIG. 3, the pivot axis (331) of
adjacent segments (302a and 302b) is perpendicular to the pivot
axis (332) of adjacent segments (302b and 302c). The alternating
pivot axes allow the torque member (300) to flex, bend, or pivot in
variety of directions as well as definable ranges about each axis.
Each pair of interlocking or linking elements (304 and 306)
transmits torque between the corresponding adjacent segments (302a,
302b, and 302c) when the torque member (300) is rotated along its
longitudinal axis. In addition, the linking elements (304 and 306)
may also provide column strength (e.g., compressive and tensile
strength) to the torque member (300), such that the torque member
(300) may have necessary column strength or integrity to be pushed
or advanced as well as pulled or retracted. For example, the
flexible torque member (300) may be pushed or advanced as well as
pulled or retracted along vasculatures or natural tortuous pathways
inside a patient. Accordingly, the elongate body (102) of an
elongate flexible torque instrument (100), which may be constructed
in part by one or more torque members, has the flexibility for
flexing, bending, or pivoting and the stiffness to transfer or
transmit twist, rotation, and torque as well as the structural
strength and integrity to be pushed or advanced and pulled or
retracted along vasculatures or natural body pathways inside a
patient.
[0050] Still referring to FIG. 3, in some embodiments, the physical
link elements (304) or splink link elements (304) of one segment
(302a, 302b, 302c) may be oriented or disposed at about 180 degrees
with respect to each other. Similarly, in some embodiments, the
torque link elements (306) or torque finger elements (306) of one
segment (302a, 302b, 302c) may be oriented or disposed at about 180
degrees with respect to each other. While in some embodiments, the
physical link elements (304) or splink link elements (304) of
adjacent segments (302a, 302b, 302c) may be oriented or disposed at
about 90 degrees with respect to each other. Similarly, in some
embodiments, the torque link elements (306) or torque finger
elements (306) of adjacent segments (302a, 302b, 302c) may be
oriented or disposed at about 90 degrees with respect to each
other.
[0051] The flexible torque member (300) may include optional guides
for steering cables (not shown) for steering the flexible torque
member. For example, the torque member (300) may comprise four
equally spaced guides along its inner surface for receiving four
steering cables. Alternatively, the guides may also be on the outer
surface of the torque member.
[0052] One advantage of the splink link configuration described
above is the fact that the torque shaft (300) requires minimal, if
any, rotation of the shaft at a proximal end before torque is
transmitted to the distal end. Before torque can be transmitted
from one end of a torque member (300) to the other end, the
rotational slack between each one of the adjacent sections or
segments (302a, 302b, 302c) of the shaft (300), if any, must be
removed by rotating the shaft (300). The minimization or entire
elimination of rotational slack allows an operator of the shaft
(300) an increased level of control and precision in guiding the
shaft (300) during delicate medical procedures.
[0053] FIG. 4 illustrates the interface of physical link element or
splink link element and torque link element or torque finger
element for one exemplary embodiment of torque shaft (400) in a
planar depiction. The planar depiction as illustrated in FIG. 4
shows the link patterns for the link elements might be cut into the
circumference of a tube, shaft, or any suitable elongate structure
(for some application, a rod or other solid elongate structure may
be used) so as to form the torque member (400). As shown, the
torque shaft (400) comprises a plurality of sections or segments
(402a, 402b, and 402c) physically connected together by living
hinges (404). Adjacent segments (402a, 402b, and 402c) are
connected to each other by a pair of living hinges (404) located
approximately 180 degrees from each other about the circumference
of the torque shaft or torque member (400). Refer to FIG. 2 and
FIG. 3 for isometric or three-dimensional depiction of a torque
member for clarification of the spatial relationship between the
link elements. The segments (402a, 402b, 402c) may be cut from a
tube, shaft, or any other suitable elongate structure, in which
thin portions of the tube may be left connected between the
segments (402a, 402b, 402c) to form the living hinges (404). The
struts (408); space, gap, or slot (410); and the male/female torque
finger elements (412, 414) may also be similarly formed in the
configuration as depicted in FIG. 4. Preferably, the stock tube,
shaft, rod, or any suitable elongate structure of which the torque
member (400) is made from may be made of a pliable material, metal,
or plastic, e.g., NITINOL (or other NiTi alloy), stainless steel,
MP35N alloy, or Polyetheretherketone (PEEK), Elgiloy, or any other
pliable material that enables the living hinges to flex, bend, or
pivot with the desired level of durability or resistance to fatigue
or without plastic deformation.
[0054] In some embodiments, spaces, gaps, or slots (410) may be cut
on both sides of each living hinge element (404) to increase the
length of the hinge element (404) to increase the amount movement
that each hinge element may be able to flex, bend, or pivot. The
living hinge elements (404) allow adjacent segments (402a, 402b,
402c) to flex, bend, or pivot relative to each. In some
embodiments, wedge-shaped portions of the elongate structure may be
cut away between adjacent segments to provide the necessary spaces
or gaps (410) such that adjacent segments may be able to flex,
bend, or pivot relative to each other. Adjacent pairs of living
hinge elements (404) may be orientated at approximately 90 degrees
from each other. For example, as illustrated in FIG. 4, the living
hinge elements (404) between adjacent segments (402a) and (402b)
are orientated at about 90 degrees with respect to each other. The
90 degree orientation between adjacent pairs of living hinge
elements (404), when used on a torque shaft (400) having a
relatively large number of segments (402a, 402b, 402c, etc.),
allows the torque shaft (400) to flex, bend, or pivot in a
substantially smooth, fluid, or substantially unencumbered manner
in various directions, e.g., X, Y, and Z directions.
[0055] Referring back to torque finger elements (314) of FIG. 3,
each pair of male torque finger elements (314) extends from a
segment (302) and is received in a pair of corresponding female
torque elements (316) of an adjacent segment (302). To allow
adjacent segments (302a, 302b, 302c) to bend about the hinge
elements (308), the female torque elements (316) are dimensioned so
that the corresponding torque finger elements (314) may slide in
and out of the female torque elements (316) to allow the adjacent
segments (302a, 302b, 302c) to flex, bend, and pivot about the link
elements (304). The torque finger elements (314), in conjunction
with the living hinge arrangement (304) described above, transmit
torque between adjacent segments (302a, 302b, 302c) of the shaft
(300) when the shaft is rotated about its longitudinal axis by
pushing against the side walls of the corresponding female torque
elements (316).
[0056] FIG. 5 depicts a torque shaft with splink link and torque
finger interlocking elements according to another embodiment. In
this embodiment, the torque shaft (500) includes the torque finger
element (510) and corresponding female torque element (512) similar
to the discussion as described above, however, the splink link
element (502) is substantially rectangular-shaped with radiused
contact surfaces as opposed to the substantially oval or
teardrop-shaped physical link element as illustrated in FIG. 2,
FIG. 3, and FIG. 4. As one of ordinary skill in the art may
appreciate, the geometrical construct of the splink-link element
may be varied without deviating from the inventive scope of the
disclosed embodiments of the present invention. In this embodiment,
the living link (506) is manufactured so that there are two
substantially curved male elements (508) surrounding the living
link (506) on either side. The space, gap, or slot (514) permits
the adjacent segments to pivot in relation to each other and allow
the overall elongate structure or torque member (500) the ability
to flex, bend, or pivot in a substantially fluid manner in various
directions, e.g., X, Y, and Z directions.
[0057] FIG. 6A illustrates a side view of a torque shaft (600) with
a wagon wheel link element (602) according to another embodiment of
the present invention. FIG. 6B illustrates an isometric view of the
same torque shaft (600). Here, the torque shaft (600) may be laser
cut in order to leave a "wagon-wheel" design that couples a
plurality of segments (612a, 612b, 612c). As one of ordinary skill
in the art having the benefit of this disclosure would appreciate,
this embodiment provides similar benefits to the torque shaft
construction previously discussed but uses a series or plurality of
living links to accomplish the task. As shown, each of the segments
(612a, 612b, 612c) has a pair of wagon wheel link elements (602) at
substantially opposite portions of each segment (612). The adjacent
segment (612) will have a pair of wagon wheel link elements (602)
at about 90 degrees offset so as to facilitate the flexible
movement of adjacent segments (612a, 612b, 612c).
[0058] Each wagon wheel link element (612) may include a hub
portion (604) and a plurality of living link elements or "spoke"
elements (606) extending from the hub (604) to rim elements (610)
of an adjacent segment (612). The degree of flexibility in this
embodiment may be affected by either the size of the spaces or gaps
(608) and/or the length of the spoke elements (606). In order to
compensate for the length needed during a compression or an
operation cycle of the spokes (606), i.e., to allow the lengthening
needed for turning of the pivot, the spoke elements (606) may have
a slight elbow bend. In other words, the spoke elements may be
"L-shaped", which may resemble the shape of an elbow. The length,
width, height, shape, orientation and number of the spokes (606)
may be tailored for a multitude of applications depending on its
intended use, i.e., modifications can vary the stiffness of the
torque member (600) and its axial/torsional strength. In another
embodiment, the L-shaped spoke structure element of the splink link
element may be implemented on a torque shaft (600) in combination
with the torque finger elements, as previously described, to
provide a flexible shaft with torque transmission capability.
[0059] FIG. 7 illustrates one example of an interface or
implementation of flexible torque members with an implant
deployment apparatus in accordance with one embodiment of the
present invention. FIG. 7 illustrates an example of an implant
deployment device (702), which may be substantially similar to the
deployment mechanism described in U.S. patent application Ser. No.
11/364,715, titled "Methods And Devices For Delivery Of Prosthetic
Heart Valves And Other Prosthetics", filed on Feb. 27, 2006; and
U.S. patent application Ser. No. 11/364,724, titled "Methods And
Devices For Delivery Of Prosthetic Heart Valves And Other
Prosthetics", filed on Feb. 27, 2006, which have been incorporated
by reference in their entirety for all purposes. Flexible torque
members (704 and 706) are operatively coupled to deployment device
(702). For example, the flexible torque member 704 may be coupled
to the wrapping pin hub (708) and flexible torque member 706 may be
coupled to the slotted tube (710). The flexible torque members (704
and 706) may apply torque to the wrapping pin hub (708) and the
slotted tube (710) to operate the deployment device (702) for
deploying and/or releasing an implant or a prosthetic device. A
prosthetic device may be similar to those described in U.S. patent
application Ser. No. 11/066,124, titled "Prosthetic Heart Valves,
Scaffolding Structures, And Systems and Methods For Implantation of
Same", filed on Feb. 25, 2005; U.S. patent application Ser. No.
11/066,126, titled "Prosthetic Heart Valves, Scaffolding
Structures, And Systems and Methods For Implantation of Same",
filed on Feb. 25, 2005; and U.S. patent application Ser. No.
11/067,330, titled "Prosthetic Heart Valves, Scaffolding
Structures, And Systems and Methods For Implantation of Same",
filed on Feb. 25, 2005; which all have been incorporated by
reference in their entirety for all purposes. In some embodiments,
the flexible torque members (704 and 706) may co-axially aligned
and they may provide counter-acting torque, counter-rotating
torque, or opposing torque to operate the wrapping pin hub (708)
and the slotted tube (710) to deploy an implant or prosthetic
device contained in the deployment device (702).
[0060] FIGS. 8A-8C show a torque shaft (800) according to an
embodiment of the invention. The torque shaft (800) comprises a
plurality of interlocking sections (812) cut into a steel tube.
Some interlocking sections (812) may have different dimensions,
e.g., one interlocking section (812) may longer (length measured in
an axial direction) than another interlocking section (812), while
other interlocking sections (812) may have substantially the same
or similar dimensions. The sections (812) are linked together by
interlocking geometry of slots (815). Each interlocking slot (815)
extends around the circumference of the tube and comprises a
plurality of interlocking features (820). The interlocking features
(820) of each slot (815) connect two adjacent sections (812) on
opposite sides of the slot (815). FIG. 8B shows an expanded view of
one of the slots (815) and FIG. 8C shows an expanded perspective
view of one of the slots (815). In this embodiment, each slot
comprises T-shaped interlocking features (820). In broader terms,
the male feature may be described as having a base and an end, and
the end has a width or height that is greater than the base. FIGS.
9A-9B show a torque shaft (900) according to another embodiment, in
which each slot (915) comprises teardrop-shaped interlocking
features (920). The geometry of the interlocking features can be
any shape that interlocks.
[0061] In the preferred embodiment, the torque shaft may be
fabricated by laser cutting the slots into a steel tube. This may
be done by moving the steel tube across a stationary laser under
computer control to precisely cut the slots. Laser cutting is well
known in the art for fabricating, e.g., stents.
[0062] Turning to FIGS. 8B and 9B, each of the slots (815, 915) has
a width W defined by the width of the laser cut. The slot width W
creates space between adjacent sections that allow adjacent
sections (812, 912) to move slightly relative to each other. This
movement allows adjacent sections (812, 912) to bend at a slight
angle (e.g., 1-2 degrees) relative to each other. The larger the
slot width W, the more adjacent sections (812, 912) can move, bend,
or pivot relative to each other.
[0063] The flexibility of the shafts (800, 900) per unit length L
depends on the amount that adjacent sections (812, 912) can bend
relative to each other and the number of slots (815, 915) per unit
length L. Since the amount that adjacent sections (812, 912) can
flex, bend, or pivot is determined by the slot width W, the
flexibility of the shafts (800, 900) per unit length is determined
by the slot width W and the number of slots (815, 915) per unit
length L. The flexibility of the shafts (800, 900) is approximately
independent of the shape of the interconnecting features of the
slots.
[0064] The interlocking slots (815, 915) allow the shafts (800,
900) to be flexible while allowing the shafts (800, 900) to
transmit torque applied at one end of the shaft to the other end of
the shaft. The torque transferring capability of the shaft (800) is
illustrated in FIG. 10, which shows an expanded view of two
adjacent interlocking features (820) of a slot (815). As the shaft
800 is rotated about it longitudinal axis in the direction
indicated by the arrow, the adjacent interlocking features (820) of
the slot (815) engage each other, at which point torque is
transferred between the adjacent sections (812) of the slot
(815).
[0065] FIG. 11 shows an interlocking slot (1115) according to
another embodiment. In this embodiment, instead of a plurality of
separate interlocking slots along the shaft, a continuous spiral or
helical slot (1115) runs along the length of the shaft (1100).
Alternatively, two or more helical slots may run along the length
of the shaft. FIG. 11 also shows an example in which two contiguous
interspaced helical slots (1125) and (1135) run along the length of
the shaft (1110) next to each other. The helical slots may have the
same interlocking geometry or different interlocking
geometries.
[0066] FIGS. 12-13 show a spot-link torque shaft (1200) according
to another embodiment of the invention. The torque shaft (1200)
comprises a plurality of interlocking sections (1212). Each section
(1212) comprises two male interlocking features (1215) on opposite
sides of the section, and two female interlocking features (1217)
on opposite sides of the section and orientated about 90 degrees
with respect to the male interlocking features (1215). The male
interlocking features (1215) have substantially circular shapes and
the female interlocking features (1217) have corresponding
substantially inwardly curved shapes for receiving the male
interlocking features (1215) therein. The male interlocking
features (1215) of each section (1212) fit into the female
interlocking features (1217) of an adjacent section (1212). This
fit enables adjacent sections (1212) to pivot relative to each
other about an axis. Each female interlocking feature (1217) curves
around the corresponding male interlocking feature (1215) may be
more than 180 degrees to prevent adjacent sections (1212) from
being pulled apart.
[0067] To provide space for adjacent sections (1212) to pivot,
portions of the tube forming the shaft are removed or cut away
between the adjacent sections. In this embodiment, wedge-shaped
portions of the tube are cut away between adjacent sections to
provide pivot spaces (1220). The pivot spaces (1220) between
adjacent sections allow adjacent sections (1212) to pivot, e.g.,
0-15 degrees, relative to each other.
[0068] The male interlocking features (1215) of adjacent sections
(1212) are orientated at about 90 degrees from each other. This is
done to enable the interlocking features to hold the sections
together. This is also done so that the pivot axes of the sections
alternate (1212) between two perpendicular axes. For example, in
FIG. 13, the pivot axis of adjacent sections (1212a) and (1212b) is
substantially perpendicular to the pivot axis of adjacent sections
(1212a) and (1212c). The alternating pivot axes allow the torque
shaft (1200) to flex, bend, or pivot in relatively unlimited
directions about the axes.
[0069] The male interlocking features (1215) also enable the torque
shaft (1200) to transmit torque from one end of the shaft to the
other end of the shaft. Each pair of male interlocking features
(1215) transmits torque between the corresponding adjacent sections
(1212) when the shaft is rotated along its longitudinal axis. In
addition, the interlocking features (1215) also provide column
strength (compressive) and tensile strength to the shaft
(1200).
[0070] The torque shaft may include optional guides for steering
cables. FIG. 12 shows an example in which the torque shaft (1200)
comprises four substantially equally spaced guides (1240) along its
inner surface for receiving four steering cables. The guides may
also be on the outer surface of the torque shaft.
[0071] The spot-link torque shaft has several advantages over the
torque shaft with interlocking slots. One advantage is that
adjacent sections of the spot-link torque shaft are able to pivot
or bend to a much greater degree than adjacent sections of the
torque shaft with interlocking slots. As a result, the spot-link
torque shaft requires far fewer sections per unit length to flex or
bend a given amount per unit length than the torque shaft with
interlocking slots. This reduction in the number of sections
reduces the amount of cutting required to fabricate the spot-link
torque shaft compared to the torque shaft with interlocking
slots.
[0072] Another advantage is that the spot-link torque shaft
requires less rotation of the shaft before torque is transmitted
from one end of the shaft to the other end of the shaft. Before
torque can be transmitted from one end of a torque shaft to the
other end, the rotational slack between each one of the adjacent
sections of the shaft must be removed by rotating the shaft.
Because the spot-link torque shaft has fewer sections than the
torque shaft with interlocking slots, the spot-link torque shaft
has less rotational slack that needs to be removed before toque is
transmitted from one end of the shaft to the other end.
[0073] FIG. 14 shows a torque shaft (1400) according to another
embodiment. The torque shaft (1400) comprises a plurality of
sections (1412a, 1412b, 1412c, etc.) connected together by living
hinges (1415). Adjacent sections (1412a, 1412b, 1412c, etc.) are
connected to each other by a pair of living hinges (1415) on
opposite sides of the shaft (1400). The sections (1412a, 1412b,
1412c, etc.) are laser cut into a tube, in which thin portions of
the tube are left connected between the sections (1412a, 1412b,
1412c, etc.) to form the living hinges (1415). Preferably, the tube
is made of a pliable metal, e.g., steel or Nitinol, or other
pliable material that enables the living hinges to flex or bend
without breaking. Slots (1417) are cut on both side of each living
hinge (1415) to increase the length of the hinge (1415) and hence
the amount that each hinge can bend. The living hinges (1415)
enable adjacent sections (1412) to flex, bend, or pivot relative to
each other. To provide space for adjacent section (1412a, 1412b,
1412c, etc.) to bend, portions of the tube are removed or cut away
between adjacent sections. In this embodiment, wedge-shaped
portions of the tube are cut away between adjacent sections to
provide space (1420) to flex.
[0074] Adjacent pairs of living hinges (1415) are orientated at
about 90 degrees from each other. For example, in FIG. 14, the pair
of living hinges (1415a) between adjacent sections (1412a and
1412b) are orientated at about 90 degrees from the pair of living
hinges (1415b) between adjacent sections (1412a and 1412b). The 90
degree orientation between adjacent pairs of living hinges (1415)
enable the torque shaft (1400) to flex or bend in many
directions.
[0075] The torque shaft further comprises a pair of torque keys
(1430) between adjacent sections (1412a, 1412b, 1412c, etc.). Each
pair of torque keys (1430) extend from opposite sides of a section
(1412a, 1412b, 1412c, etc.) and is received in a pair of slots
(1435) in an adjacent section (1412a, 1412b, 1412c, etc). To allow
adjacent sections (1412a, 1412b, 1412c, etc.) to bend about the
hinges (1415), the slots (1435) are dimensioned so that the
corresponding torque keys (1430) can slide in the slots (1435) to
allow flexing, bending, or pivoting. The torque keys (1430)
transmit torque between adjacent sections (1412a, 1412b, 1412c,
etc.) of the shaft when the shaft is rotated about its longitudinal
axis by pushing against the side walls of the corresponding slots
(1435). The torque keys (1430) may be contiguous with the sections
(1412a, 1412b, 1412c, etc.) or may be made of separate pieces
attached to the sections (1412a, 1412b, 1412c, etc.).
[0076] FIGS. 15-16 show two views of two torque shafts (1502 and
1504) with one of the torque shafts (1504) disposed within the
other torque shaft (1502). As explained above, a torque shaft has
to be rotated by a certain amount at one end before torque may be
transmitted to the other end of the shaft. This amount of rotation
is referred to as wind-up. In this example, the two torque shafts
(1502 and 1504) may be operated to provide opposing torque as
indicated by the arrows in the FIGS. 15 and 16. Since the two
torque shafts (1502 and 1504) provide torque or rotation in oppose
directions, each torque shaft may be pre-wound or pre-loaded to
remove wind-up before use. In FIG. 15, the outer torque shaft
(1502) may be pre-wound in the counter clockwise direction and the
inner torque shaft (1504) may be pre-wound in the clockwise
direction as indicated by arrows. The torque shafts (1502 and 1504)
may be pre-wound until the wind-up slack is removed from each of
the two shafts (1502 and 1504). When the torque shafts (1502 and
1504) are pre-wound, the outer torque shaft (1502) may tendency to
unravel in the clockwise direction and the inner torque shaft
(1504) may have a tendency to unravel in the counter clockwise
direction. To prevent the torque shafts (1502 and 1504) from
unraveling after they are pre-wound, an interlocking feature may be
placed between the two torque shafts.
[0077] FIG. 16 shows an example of a pin (1525) connected to the
inner torque shaft (1504) and received in a slot (1530) in the
outer torque shaft (1502). The pin (1525) engages an end surface of
slot (1530), which prevents the two torque shafts (1502 and 15204)
from unraveling. The slot (1530) runs along part of the
circumference of the outer shaft (1502) to allow the ends of the
torque shafts (1502 and 1504) to be rotated in opposing
direction.
[0078] FIG. 17 shows an exploded and a perspective view of an
example of pull-pull torque drive (1700) according to an
embodiment. The torque drive (1700) comprises a slotted tube
(1710), a cable drum hub (1720), and a sheave (1730). The drum hub
(1720) is placed in the tube (1710) and rotates on the sheave
(1730). The torque drive (1700) further comprises two cables (1735)
running through coil pipes (1750) (only one of the cables is shown
in FIG. 17). The cables (1735) are threaded through channels (1740)
in the sheave (1730) and wound around the drum hub (1720) in
different directions. The end of each cable (1735) is attached to
the drum hub (1720). FIG. 17 shows one of the cables (1735) wound
around the hub (1720) in one direction. The other cable (not shown)
is wound around the hub (1720) in the opposite direction.
[0079] The cables (1735) enable the cable drum hub (1720) to be
rotated in either direction with respect to the tube (1710) by
pulling one of the cables (1735) axially. Pulling on one of the
cables (1735) causes that one of the cables (1735) to unwind around
the hub (1720); thereby, rotating the hub (1720). This also causes
the other cable (1735) to wind around the hub (1720) so that the
hub (1720) can be rotated in the other direction by pulling the
other cable (1735).
[0080] The pull-pull torque drive (1700) is useful for deploying a
prosthetic heart valve in a patient, which is described in more
detail in application Ser. No. 11/066,126, filed on Sep. 15,
2005.
[0081] FIG. 18 shows a device (1800) for translating axial movement
of the shaft (1825) into rotational movement of the shaft (1810).
This may be used for transmitting torque to the distal end of the
shaft by applying axial force to the proximal end of the shaft. The
device (1800) comprises a cylindrical sleeve (1810) with a curved
slot (1820) and a pin (1815) connected to the shaft (1825) that
slides in the slot (1820). When axial force is applied to the shaft
(1825), the pin (1815) connected to the shaft travels along the
curved slot (1820) of the sleeve (1810) causing the sleeve (1810)
to rotate.
[0082] FIG. 19A illustrates an elongate flexible torque instrument
(100) being used to deliver an implant to a target site inside a
patient in accordance with one embodiment of the present invention.
The process of using the elongate flexible torque instrument (100)
to deliver and deploy an implant is illustrated in process
flowchart of FIG. 19B. The process starts by inserting a distal
portion of an elongate flexible torque instrument into a patient,
in step (1910). Typically, the insertion is made through either a
natural body opening or small incision. As illustrated in FIG. 19A,
a small incision is made near the femoral vessel and the distal
portion of the elongate flexible torque instrument (100) is
advanced and navigated through the vasculature of the patient, in
step (1920). In this example, the distal portion of the elongate
flexible torque instrument (100) may be advanced and navigated up
to the inferior vena cava and into the right ventricle of the
patient's heart. The distal portion of the elongate flexible torque
instrument (100) is further advanced through the septum and into
the left ventricle of the heart. From there, the distal portion of
the elongate flexible torque instrument is navigated down,
approximately 90 degrees or more, and through the mitral valve and
into the left atrium, as illustrated in FIG. 19C. Throughout this
procedure the elongate body (102) may be required to be steered or
navigated in various directions and the torque members of the
elongate body (102) may be flexed, bent, and/or pivoted in order to
accommodate the movement of the elongate body (102) through various
tortuous pathways of the vasculature. In addition, the elongate
body (102) and the flexible torque members may be flexed, bent,
and/or pivoted into various complex shapes and tight curvatures. As
further illustrated in FIG. 19C, the distal portion of the elongate
flexible torque instrument (100) is further navigated and advanced
up the aortic arch, which may require a significant tight turn,
approximately 180 degrees, and the distal portion of the flexible
torque instrument may be bent into a tight "J" shaped curvature.
That is, the distal portion of the elongate flexible instrument may
be bent in a way that is double-back forward itself type of
configuration. As previously discussed, the segment members of the
flexible torque member are particularly configured to allow such
flexibility for the elongate body to form complex shapes and tight
curvatures. As the distal portion of the elongate flexible torque
instrument (100) is navigated into position, torque is applied at
the proximal portion and transmitted to the distal portion of the
elongate flexible instrument to operate an implant deployment
apparatus (112), in step (1930). In this example, the transmitted
torque operates an implant deployment apparatus (112) and an
implant is deployed from the deployment apparatus (112) to a
location at or near the aortic root, in step (1940). This procedure
in delivering an implant may be known as the antegrade approach.
Alternatively, a retrograde approach may also be used to deliver an
implant, as illustrated in FIG. 19D. In this procedure, similar to
the process described in the flowchart of FIG. 19B. The process
starts by inserting a distal portion of an elongate flexible torque
instrument (100) into a patient. Typically, the insertion is made
through either a natural body opening or small incision. In the
example illustrated in FIG. 19A, a small incision is made near the
femoral vessel and the distal portion of the elongate flexible
torque instrument (100) is advanced and navigated through the
vasculature of the patient. In the retrograde approach, the distal
portion of the elongate flexible torque instrument is navigated
from the femoral vessel through the vasculature to the aortic arch.
Throughout this procedure the elongate body (102) may be required
to be steer or navigated to various directions and the torque
members of the elongate body (102) may be flexed, bent, and/or
pivoted in order to accommodate the movement of the elongate body
(102) through various tortuous pathways of the vasculature. The
distal portion of the elongate flexible torque instrument (100) is
navigated in to position at or near the aortic valve by way of the
aortic arch, and then torque may be applied at the proximal portion
and transmitted to the distal portion of the elongate flexible
instrument to operate an implant deployment apparatus (112). In
this example, the transmitted torque operates an implant deployment
apparatus (112) and an implant is deployed from the deployment
apparatus (112) to a location at or near the aortic root.
[0083] While the specification describes particular embodiments of
the present inventive subject matter, those of ordinary skill in
the art having the benefit of this disclosure can devise variations
of the subject matter without departing from the inventive
concepts. In addition, the previous description is provided to
enable a person of ordinary skill in the art to practice the
various embodiments described herein. Various modifications to
these embodiments will be readily apparent to those of ordinary
skill in the art, and the generic principles defined herein may be
applied to other embodiments. Thus, the claims are not intended to
be limited to the embodiments shown herein, but are to be accorded
the full scope consistent with the language of the claims, wherein
reference to an element in the singular is not intended to mean
"one and only one" unless specifically so stated, but rather "one
or more." All structural and functional equivalents to the elements
of the various embodiments described throughout this disclosure
that are known or later come to be known to those of ordinary skill
in the art are expressly incorporated herein by reference and are
intended to be encompassed by the claims. Moreover, nothing
disclosed herein is intended to be dedicated to the public
regardless of whether such disclosure is explicitly recited in the
claims. No claim element is to be construed under the provisions of
35 U.S.C. .sctn. 112, sixth paragraph, unless the element is
expressly recited using the phrase "means for" or, in the case of a
method claim, the element is recited using the phrase "step
for."
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