U.S. patent application number 12/131831 was filed with the patent office on 2008-09-18 for cardiac visualization devices and methods.
This patent application is currently assigned to Guided Delivery Systems, Inc.. Invention is credited to Rodolfo A. Morales, Nick Pliam, Niel F. Starksen, John To.
Application Number | 20080228032 12/131831 |
Document ID | / |
Family ID | 34622836 |
Filed Date | 2008-09-18 |
United States Patent
Application |
20080228032 |
Kind Code |
A1 |
Starksen; Niel F. ; et
al. |
September 18, 2008 |
CARDIAC VISUALIZATION DEVICES AND METHODS
Abstract
Devices and methods for facilitating transvascular, minimally
invasive and other "less invasive" surgical procedures generally
include a sheath with an expandable balloon at the distal end, an
inflation lumen for expanding the balloon, and a device passage
lumen for allowing passage of one or more surgical instruments. The
sheath is configured to house at least one visualization device
such that an optical element of the device is positioned to view
the surgical site. In some embodiments, instruments may be passed
through the sheath, with the distal balloon partially or fully
circumscribing or encircling the instruments. Any suitable
instrument(s) may be passed through sheaths of the invention, such
as a surgical clip applier for repairing a heart valve, an ablation
member for treating atrial fibrillation, one or more pacemaker
leads, a coronary sinus access device or the like.
Inventors: |
Starksen; Niel F.; (Los
Altos Hills, CA) ; Pliam; Nick; (Los Altos, CA)
; Morales; Rodolfo A.; (Los Gatos, CA) ; To;
John; (Newark, CA) |
Correspondence
Address: |
MORRISON & FOERSTER LLP
755 PAGE MILL RD
PALO ALTO
CA
94304-1018
US
|
Assignee: |
Guided Delivery Systems,
Inc.
Santa Clara
CA
|
Family ID: |
34622836 |
Appl. No.: |
12/131831 |
Filed: |
June 2, 2008 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10927784 |
Aug 27, 2004 |
|
|
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12131831 |
|
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|
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60500773 |
Sep 3, 2003 |
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Current U.S.
Class: |
600/109 ;
600/115; 606/194 |
Current CPC
Class: |
A61B 2017/00243
20130101; A61B 18/1492 20130101; A61B 17/00234 20130101; A61B
17/1285 20130101 |
Class at
Publication: |
600/109 ;
600/115; 606/194 |
International
Class: |
A61B 1/04 20060101
A61B001/04; A61B 1/01 20060101 A61B001/01; A61M 29/00 20060101
A61M029/00 |
Claims
1-87. (canceled)
88. A device comprising: an elongate member having a lumen
extending therethrough; and an expandable member connected to, and
expandable from, the distal end of the elongate member, wherein the
expandable member defines a continuous aperture along and through
the entire longitudinal length of the expandable member when the
expandable member is in the expanded configuration, the aperture
having a diameter allowing for passage of at least one device for
performing a heart procedure therethrough, wherein the device is
selected from the group consisting of an ablation device, an
electrocautery device, a suturing device, and a cutting device.
89. The device of claim 88, wherein the expandable member is
frustoconical.
90. The device of claim 88, wherein the expandable member is
toroidal.
91. The device of claim 88, wherein the expandable member is an
inflatable balloon.
92. The device of claim 91, wherein the inflatable balloon
comprises one or more inflation lumens.
93. The device of claim 88, wherein a diameter of the lumen is the
same as the diameter of the aperture.
94. The device of claim 88, further comprising one or more
visualization devices.
95. The device of claim 94, wherein the visualization device is
selected from the group consisting of a fiber optic device, an
ultrasonic device, a charge coupled device, and a camera.
96. The device of claim 88, wherein the elongate member is slidably
disposed within an outer tubular member.
97. The device of claim 96, wherein the length of the expandable
member is adjusted by sliding the outer tubular member along the
elongate member.
98. The device of claim 88, wherein the elongate member is
flexible.
99. The device of claim 88, wherein the elongate member is a
catheter.
100. A method comprising: advancing an elongate member having a
lumen extending therethrough adjacent to heart tissue; expanding an
expandable member connected to, and expandable from, a distal end
of an elongate member, wherein the expandable member defines a
continuous aperture along and through the entire longitudinal
length thereof; and advancing at least one device through the
continuous aperture where the device is selected from the group
consisting of an ablation device, an electrocautery device, a
suturing device, and a cutting device.
101. The method of claim 99, further comprising adjusting the size
of the expandable member by sliding a sheath along the elongate
member.
102. The method of claim 99, further comprising visualizing the
location using a visualization device disposed within the
expandable member.
103. The method of claim 99, wherein the heart procedure is mitral
valve repair.
104. The method of claim 99, wherein the heart procedure is a
laparoscopic procedure.
105. The method of claim 99, wherein the elongate member is
advanced through the superior vena cava into the right atrium and
through the interatrial septum.
106. The method of claim 99, wherein the elongate member is
advanced through the inferior vena cava into the right atrium and
through the interatrial septum.
107. A device comprising: an elongate member having a lumen
extending therethrough; and an expandable member having a proximal
end directly coupled to, and expandable from, the distal end of the
elongate member, wherein the expandable member defines a continuous
aperture along and through the entire longitudinal length of the
expandable member when the expandable member is in the expanded
configuration, the aperture having a diameter allowing for passage
of at least one device for performing a heart procedure
therethrough, wherein the device is selected from the group
consisting of an ablation device, an electrocautery device, a
suturing device, and a cutting device.
108. The device of claim 107, further comprising a visualization
device disposed within the expandable member.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Application
60/500,733 filed on Sep. 3, 2003 (Attorney Docket (GDS 1010-1).
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to medical devices
and methods. More particularly, the invention relates to
visualization devices and methods for facilitating cardiac surgical
procedures, such as repair of the mitral or tricuspid valve for
treating mitral or tricuspid regurgitation.
[0004] In recent years, many advances have been made to reduce the
invasiveness of cardiac surgery. In an attempt to avoid open,
stopped-heart procedures, which may be accompanied by high patient
morbidity and mortality, many devices and methods have been
developed for operating on a heart through smaller incisions,
operating on a beating heart, and even performing cardiac
procedures via transvascular access. Different types of cardiac
procedures, such as cardiac ablation techniques for treating atrial
fibrillation, stenting procedures for atherosclerosis, and valve
repair procedures for treating conditions such as mitral
regurgitation have experienced significant technological advances.
In implementing many, if not all, transvascular, minimally invasive
and other cardiac surgery techniques, visualization of the heart,
the surgical field, surrounding structures, and the like is
essential. At the same time, visualization is often difficult, due
to the rapid movement of a beating heart as well as the large
quantities of pumping blood in an intracardiac surgical field.
[0005] One type of cardiac surgery which may benefit from less
invasive techniques is heart valve repair. Traditional treatment of
heart valve stenosis or regurgitation, such as mitral or tricuspid
regurgitation, typically involves an open-heart surgical procedure
to replace or repair the valve. Valve repair procedures typically
involve annuloplasty, a set of techniques designed to restore the
valve annulus shape and strengthen the annulus. Conventional
annuloplasty surgery generally requires a large incision into the
thorax of the patient (a thoracotomy), and sometimes a median
sternotomy (cutting through the middle of the sternum). These open
heart, open chest procedures routinely involve placing the patient
on a cardiopulmonary bypass machine for sustained periods so that
the patient's heart and lungs can be artificially stopped during
the procedure. Finally, valve repair and replacement procedures are
typically technically challenging and require a relatively large
incision through the wall of the heart to access the valve.
[0006] Due to the highly invasive nature of open heart valve repair
or replacement, many patients, such as elderly patients, patients
having recently undergone other surgical procedures, patients with
comorbid medical conditions, children, late-stage heart failure
patients, and the like, are often considered too high-risk to
undergo heart valve surgery and are relegated to progressive
deterioration and cardiac enlargement. Often, such patients have no
feasible alternative treatments for their heart valve
conditions.
[0007] To obviate this situation, a number of devices and methods
for repairing a mitral valve to treat mitral regurgitation in a
less invasive manner have been developed. Some devices provide for
heart valve repair through minimally invasive incisions or
intravascularly, while others improve upon open heart surgical
procedures on beating hearts, stopped hearts or both. For example,
several improved devices and methods for heart valve repair are
described in one or more patent applications filed by the inventors
of the present invention and assigned to the assignee of the
present invention. For further description of such devices and
methods, reference may be made to U.S. patent application Ser. No.
10/461043 (Attorney Docket No. 16886-000310), filed on Jun. 13,
2003, which is hereby incorporated fully by reference.
[0008] As mentioned above, one of the main challenges in performing
minimally invasive surgery on a heart, heart valve, or any other
structure is obtaining adequate visualization of the structure and
the surgical field. Visualizing a cardiac valve annulus in a
beating heart procedure is especially challenging due to rapid
movement of the annulus and the heart, the small size of the
annulus, and the blood-filled surgical field. Current visualization
of minimally invasive cardiac procedures is typically accomplished
via transesophageal echocardiogram (TEE). Although this technique
works relatively well for some cardiac procedures, it does not
provide as clear a picture of the surgical site as would direct
visualization. Thus, TEE may not be sufficient for visualizing a
minimally invasive procedure within the heart, especially a beating
heart procedure to repair a valve annulus.
[0009] To obtain direct visualization within the heart, any
suitable endoscopic device may be introduced into the heart, such
as a conventional endoscope or ultrasonic probe. One problem
encountered with such devices, however, is that their ability to
provide visualization is often severely reduced by the presence of
blood in the heart that surrounds the optic element of the
visualization device. A number of devices have been described to
combat this problem. For example, U.S. Pat. No. 6,346,074, issued
to Roth on Feb. 12, 2002, describes an endoscope having a distal
balloon over its end. Such devices still have certain shortcomings,
however. For example, balloon-covered endoscope devices are
typically introduced into the surgical site through a sheath or
introducer device separately from any of the instruments used to
perform the cardiac procedure. Thus, the visualization device must
typically be manipulated apart from the surgical instruments, and
the optical element of the device may often be positioned
significantly apart from the working ends of the instruments and
the surgical site. In other balloon endoscope devices, the
endoscope must be advanced to the surgical site to visualize the
site and then removed to allow a surgical instrument to be advanced
through the same sheath to perform the procedure. Obviously, such a
technique may require numerous, awkward switch-outs of endoscope
and surgical instrument and will not result in direct, real-time
visualization of the procedure.
[0010] Many minimally invasive or "less invasive" surgical
procedures other than heart valve repair would also benefit from
improved visualization. For example, improved visualization could
facilitate other cardiac procedures, such as accessing the coronary
sinus for placement of an implantable device or for performing a
procedure, placing pacemaker leads in one or more areas of the
heart, ablation procedures such as ablation around the pulmonary
veins to treat atrial fibrillation, atrial-septal defect repair
procedures, and the like. Improved visualization could also be used
to enhance non-cardiac procedures such cinching or otherwise
treating a bladder, stomach, gastroesophageal junction, vascular
structure, gall bladder or the like.
[0011] Therefore, it would be beneficial to have improved
visualization devices and methods for use in transvascular,
minimally invasive and other "less invasive" surgical procedures,
such as heart valve repair and other cardiac procedures. Devices
and methods for providing such visualization would ideally be
minimally invasive and would enhance a physician's ability to
locate, visualize and repair a valve annulus, atrial-septal defect,
or other cardiac structure accurately and efficiently. Ideally,
visualization of the surgical site would be as direct as possible,
with an optic element of the visualization device being positioned
close to the site. Also ideally, the visualization device would
provide visualization at the same time that the physician was
performing the procedure and further provide or facilitate access
for surgical and/or diagnostic instruments to operate in the
visualized field. At least some of these objectives will be met by
the present invention.
[0012] 2. Description of the Background Art
[0013] U.S. Pat. No. 6,346,074 describes an endoscope having a
balloon over its distal end for use in intracardiac surgery. Patent
publications related to mitral valve repair include WO01/26586;
US2002/0163784A12; US2002/0156526; US2002/0042621; 2002/0087169;
US2001/0005787; US2001/0014800; US2002/0013621; US2002/0029080;
US2002/0035361; US2002/0042621; US2002/0095167; and US2003/0074012.
U.S. patents related to mitral valve repair include U.S. Pat. Nos.
4,014,492; 4,042,979; 4,043,504; 4,055,861; 4,700,250; 5,366,479;
5,450,860; 5,571,215; 5,674,279; 5,709,695; 5,752,518; 5,848,969;
5,860,992; 5,904,651; 5,961,539; 5,972,004; 6,165,183; 6,197,017;
6,250,308; 6,260,552; 6,283,993; 6,269,819; 6,312,447; 6,332,893;
and 6,524,338. Publications of interest include De Simone et al.
(1993) Am. J. Cardiol. 73:721-722 and Downing et al. (2001) Heart
Surgery Forum, Abstract 7025.
BRIEF SUMMARY OF THE INVENTION
[0014] Devices and methods of the present invention facilitate
transvascular, minimally invasive and other "less invasive"
surgical procedures, such as heart valve repair procedures, by
providing direct visualization of a surgical site. "Less invasive,"
for the purposes of this application, means any procedure that is
less invasive than traditional, large-incision open surgical
procedures. Thus, a less invasive procedure may be an open surgical
procedure involving one or more smaller incisions, a transvascular
percutaneous procedure, a transvascular procedure via out-down, a
laparoscopic procedure, or the like. Generally, any procedure in
which a goal is to minimize or reduce invasiveness to the patient
may be considered less invasive. Furthermore, although the terms
"less invasive" and "minimally invasive" may sometimes be used
interchangeably in this application, neither these nor other
descriptive terms should be interpreted to limit the scope of the
invention. Generally, visualization devices and methods of the
invention may be used in performing or enhancing any suitable
procedure.
[0015] In addition to facilitating visualization, devices and
methods of the invention also facilitate access for positioning one
or more instruments to the surgical site for performing a
procedure. The devices generally include a sheath with an
expandable balloon at the distal end, an inflation lumen for
expanding the balloon, and a device passage lumen for allowing
passage of one or more surgical instruments. The sheath is
configured to house at least one visualization device such that an
optical element of the device is positioned to view the surgical
site. In some embodiments, instruments may be passed through the
sheath, with the distal balloon partially or fully circumscribing
or encircling the instruments. In other embodiments, the balloon
may be adjacent, but not encircling, a lumen for instrument
passage. Any suitable instrument(s) may be passed through sheaths
of the invention, such as a surgical clip applier for repairing a
heart valve, an ablation member for treating atrial fibrillation, a
suturing device, and/or the like. By positioning a lumen for
passage of instruments adjacent a balloon-covered visualization
device, sheaths of the present invention provide improved, direct
visualization of a surgical site for performing a procedure.
[0016] As mentioned above, the present application often focuses on
visualization devices and methods as used in heart valve repair,
and more specifically mitral valve repair to treat mitral
regurgitation. It should be emphasized, however, that visualization
devices and methods of the invention may be used in any suitable
procedure, both cardiac and non-cardiac. For example, they may be
used in procedures to repair the aortic or pulmonary valve, to
repair an atrial-septal defect, to access and possibly perform a
procedure from the coronary sinus, to place one or more pacemaker
leads, to perform a cardiac ablation procedure, and/or the like. In
other embodiments, the devices and methods may be used to enhance a
laparoscopic or other endoscopic procedure on any part of the body,
such as the bladder, stomach, gastroesophageal junction,
vasculature, gall bladder, or the like. Therefore, although the
following description typically focuses on mitral valve and other
heart valve repair, such description should not be interpreted to
limit the scope of the invention as defined by the claims.
[0017] That being said, in one aspect of the invention, a method
for performing a procedure on a heart involves first advancing an
elongate sheath to a location in the heart for performing the
procedure. Next, an expandable balloon coupled with a distal end of
the elongate sheath is inflated and the location in the heart is
visualized through the expandable balloon, using at least one
visualization device disposed in the elongate sheath. Finally, at
least part of the procedure is performed using one or more
instruments extending through a first lumen of the elongate
sheath.
[0018] In some embodiments, the elongate sheath may be flexible so
that it may be advanced through the vasculature of a patient to
position at least a distal portion of the sheath in the heart. For
example, the sheath may be advanced through the internal jugular
vein, superior vena cava, right atrium and interatrial septum of
the patient to position the distal portion of the sheath in the
left atrium. Alternatively, the sheath may be advanced through the
internal jugular vein, superior vena cava, right atrium, coronary
sinus and left atrial wall of the patient to position the distal
portion of the sheath in the left atrium. In still another
embodiment, a flexible sheath may be advanced through the femoral
vein, inferior vena cava, right atrium and interatrial septum. In
other embodiments, the sheath may be rigid and may be introduced
via thorascopically or otherwise through the heart wall.
[0019] Inflating the balloon typically involves injecting a fluid
into the balloon via a second lumen in the sheath, though any other
inflation method may be used. The balloon may have any shape, such
as a toroidal balloon encircling the first lumen or a spherical or
ovoid balloon adjacent the first lumen. Optionally, methods may
further include passing at least one fluid through the first lumen
to flush the location for performing the procedure and/or to
cleanse one or more instruments positioned in the first lumen. Also
optionally, a method may include retracting an outer tubular member
to expose additional expandable balloon material from the distal
end of the sheath and further inflating the expandable balloon.
[0020] The visualizing step may be performed using any suitable
visualization device in any location. For example, a fiberoptic
viewing scope, typically in combination with a fiberoptic or other
illuminator may be used. Another embodiment may employ a charge
coupled device with illumination, essentially a small camera, for
visualization. In some embodiments, the visualization device is
disposed within the elongate sheath for visualizing the surgical
site. Sometimes, the visualization device is disposed in a second
lumen of the sheath, the second lumen comprising an inflation lumen
for inflating the expandable balloon. In some embodiments, a
separate visualization device may be passed into the sheath through
the second lumen to position the visualization device for
visualizing the location. In some embodiments, the visualization
device is disposed between an outer tubular member and an inner
tubular member of the sheath. The annular space between the two
tubular members may also act as an inflation lumen.
[0021] Optionally, the method may include visualizing a first view
of the location with the visualization device in a first position
in the sheath, moving the visualization device to at least a second
position in the sheath, and visualizing a second view of the
location with the visualization device in the second position.
Thus, two or more different views of a surgical site may be
acquired using the sheath device and one visualization device;
Alternatively, visualization of multiple views may be accomplished
via a plurality of visualization devices disposed at various
positions in the sheath, for example, disposed at different
circumferential positions surrounding a central device passage
lumen. In these and other embodiments, a central processing unit
may be used to process captured images of the surgical site. Such
processed images may then be transmitted proximally for viewing by
the physician. For example, in one embodiment visualization may be
achieved using a light source and one or more sensors or detectors
disposed in a 360-degree array around an inner, device-passage
lumen, the light source and the detectors disposed at the distal
end of a visualization device. The sensors may then be coupled with
a charge coupled device (CCD) disposed near the distal end of the
device, the CCD being coupled with a wire that transmits data
proximally along the visualization device.
[0022] Any suitable surgical procedure may be performed using the
devices and methods of the invention. Typically, the procedures
will be transvascular, minimally invasive, or other "less invasive"
procedures, as discussed above. In some embodiments, the procedure
involves repairing a heart valve, such as a mitral, tricuspid,
aortic or pulmonary valve. For example, repairing the valve may
involve applying clips to a valve annulus using a clip applier
extending through the first lumen of the sheath. Such a procedure
may further include cinching a tether coupled with the applied
clips to decrease a diameter of the valve annulus. In some
embodiments, the procedure may be further enhanced by passing a
fluid, such as saline, through the first lumen in a direction from
a proximal end of the sheath toward the distal end of the sheath to
cleanse the surgical instrument(s), clear an area around the
surgical site, and/or cleanse the external surface of the
balloon.
[0023] In another aspect, a device for facilitating a procedure on
a heart includes an elongate sheath having a proximal end, a distal
end, a first lumen extending from the proximal end to the distal
end, and at least a second lumen, and an expandable balloon coupled
with the elongate sheath at or near the distal end, wherein the
balloon at least partially encircles the first lumen, and the
second lumen opens into the balloon for inflating the balloon. The
elongate sheath may include one or more rigid tubular members
and/or one or more flexible tubular members. In some embodiments,
for example, the sheath includes an inner tubular member having an
inner surface defining the first lumen and an outer tubular member
disposed over the inner tubular member. In such embodiments, the
annular space between the inner tubular member and the outer
tubular member may form the second lumen.
[0024] The expandable balloon may be coupled with the inner tubular
member and the outer tubular member at or near the distal end of
the sheath such that the second lumen acts as an inflation lumen.
Such a balloon may be toroidal in shape, for example, with the
first lumen being continuous with a central aperture in the
toroidal balloon. Optionally, the outer member may be slidable
proximally to expose additional material of the expandable balloon
to allow the balloon to further expand. In an alternative
embodiment, an slidable outer sleeve may be disposed over the outer
tubular member to provide for additional exposure and expansion of
an expandable balloon.
[0025] The sheath may also include at least one visualization
device disposed within the second lumen. For example, the
visualization device may include one or more fiber optic devices,
ultrasound transducers, charge coupled devices, cameras, light
sources and/or sensors. In some embodiments, the distal end of the
visualization device is disposed within the expandable balloon.
Also in some embodiments, the visualization device is movable
within the sheath. For example, where the sheath comprises an inner
tubular member and an outer tubular member and the second lumen
comprises an annular space between the inner and outer tubular
members, the visualization member may be movable around the
circumference of the second lumen. In alternative embodiments, the
sheath may not include a visualization device but may have a lumen,
such as the second lumen, that is sufficiently large to allow
passage of at least one visualization device to position a distal
end of the device within the expandable balloon.
[0026] In some embodiments, the inner diameter of the first lumen
is sufficiently large to allow passage of at least one instrument
for performing the procedure on the heart. A variety of surgical
instruments may thus be passed, though they will often be
catheter-based, transvascular, or other less invasive instruments.
In one embodiment, the instrument is clip applier for applying a
plurality of tethered clips to a valve annulus of the heart and
cinching a tether coupled with the clips to reduce a diameter of
the valve. In another embodiment, the instrument may be an ablation
member for ablating a portion of the heart, such as in a procedure
to treat atrial fibrillation.
[0027] In another aspect of the invention, a device for
facilitating a procedure on a heart includes an elongate sheath
having a proximal end, a distal end, a first lumen extending from
the proximal end to the distal end, and at least a second lumen,
and an expandable balloon coupled with the elongate sheath at or
near the distal end and adjacent the first lumen, wherein the
second lumen opens into the balloon for inflating the balloon.
Unlike the embodiment just described, here the surgical
instrument(s) may pass adjacent to but not through the balloon.
Typically, in such embodiments, the balloon will have a spherical,
ovoid or other suitable shape, but will not be toroidal or
"donut-shaped" as in the embodiments described above. These and
other embodiments are described more fully below, with reference to
the appended drawing figures.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] FIG. 1 is a frontal, cross-sectional view of a human heart
with a visualization device positioned for performing an
intracardiac procedure, in accordance with one embodiment of the
present invention;
[0029] FIG. 2 is a perspective view of a visualization device for
performing a minimally invasive cardiac procedure, in accordance
with one embodiment of the present invention;
[0030] FIG. 3 is a side, cross-sectional view of the visualization
device in FIG. 2; and
[0031] FIG. 4 is a perspective view of a visualization device for
performing a minimally invasive cardiac procedure, in accordance
with another embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0032] Devices and methods for facilitating transvascular,
minimally invasive and other "less invasive" surgical procedures
generally include a sheath with an expandable balloon at the distal
end, an inflation lumen for expanding the balloon, and a device
passage lumen for allowing passage of one or more surgical
instruments. The sheath is configured to house at least one
visualization device such that an optical element of the device is
positioned to view the surgical site. In some embodiments,
instruments may be passed through the sheath, with the distal
balloon partially or fully circumscribing or encircling the
instruments. In other embodiments, the balloon may be adjacent, but
not encircling, a lumen for instrument passage. Any suitable
instrument(s) may be passed through sheaths of the invention, such
as a surgical clip applier for repairing a heart valve, an ablation
member for treating atrial fibrillation, a suturing device, and/or
the like. By positioning a lumen for passage of instruments
adjacent a balloon-covered visualization device, sheaths of the
present invention provide improved, direct visualization of a
surgical site for performing a procedure.
[0033] As discussed above, the present application often focuses on
visualization devices and methods as used in heart valve repair,
and more specifically mitral valve repair to treat mitral
regurgitation. It should be emphasized, however, that visualization
devices and methods of the invention may be used in any suitable
procedure, both cardiac and non-cardiac. For example, they may be
used in procedures to repair the aortic or pulmonary valve, to
repair an atrial-septal defect, to access and possibly perform a
procedure from the coronary sinus, to place one or more pacemaker
leads, to perform a cardiac ablation procedure, and/or the like. In
other embodiments, the devices and methods may be used to enhance a
laparoscopic or other endoscopic procedure on any part of the body,
such as the bladder, stomach, gastroesophageal junction,
vasculature, gall bladder, or the like. Therefore, although the
following description typically focuses on mitral valve and other
heart valve repair, such description should not be interpreted to
limit the scope of the invention as defined by the claims.
[0034] That being said, and referring now to FIG. 1, an exemplary
sheath 10 of the present invention suitably comprises an elongate
tubular member 11 having a distal end and a proximal end. An
expandable balloon 12 is typically coupled with sheath 10 at or
near the distal end, and one or more treatment devices 14 may be
passed through an aperture in the distal end. One or more
visualization devices (not shown) may be coupled with or inserted
into sheath 10 such that an optical element of the visualization
device(s) extends up to or within balloon 12.
[0035] Generally, sheath 10 may be flexible, rigid, or
part-flexible part-rigid, and may be introduced to a surgical site
via any suitable method or route. In FIG. 1, for example, sheath 10
has been advanced to the mitral valve MV of a heart H through the
superior vena cava SVC, right atrium RA, foramen ovale FO, and left
atrium LA. Access to the superior vena cava SVC may be gained, for
example, via the internal jugular vein. In other embodiments,
access to the RA may be gained through the femoral vein and the
inferior vena cava. Thus, access to the heart H may be achieved via
a transvascular route. Alternatively, sheath 10 may be introduced
through an incision and/or access port in the wall of the left
atrium LA. Such access is discussed more fully in U.S. patent
application Ser. No. 10/461043 (Attorney Docket No. 16886-000310),
previously incorporated by reference. Any other suitable minimally
invasive means for gaining access may alternatively be used to
position sheath 10 in a desired location for visualizing and
performing a procedure.
[0036] Referring now to FIGS. 2 and 3, one embodiment of sheath 10
suitably includes an outer tubular member 11 and an inner tubular
member 13, with the annular space between the two tubular members
comprising an inflation lumen 22 and the space within inner tubular
member 13 comprising a device passage lumen 20. An expandable
balloon 12 is coupled with at least one of the two tubular members
at or near the distal end of sheath 10. In FIGS. 2 and 3, balloon
12 is coupled with both tubular members such that inflation lumen
22 opens distally into balloon 12. In this embodiment, balloon 12
has a toroidal or "donut" shape, such that balloon 12 encircles
device passage lumen 20, and an aperture 15 in balloon 12 allows
one or more treatment devices 14 to extend from the distal end of
device passage lumen 20 through balloon 12. A visualization device
24 is disposed within inflation lumen 22 such that a distal portion
of visualization device 24, including an optical element 26,
extends into balloon 12. Treatment device 14 in this embodiment
comprises a clip applier for applying tethered clips to a heart
valve annulus, shown with a protruding clip 16 and clip tether 18.
Clip appliers for heart valve repair are described more fully in
U.S. patent application Ser. No. 10/461043, previously incorporated
by reference. Of course, any other suitable treatment device may
alternatively be used with sheath 10, such as a hook applier, a
suture applier, an ablation device, a scalpel or other cutting
device such as an electrocautery device, and/or the like.
[0037] Inner tubular member 13 and outer tubular member 11 of
sheath 10 may comprise any suitable material or combination of
materials and may have any suitable shape, size, diameters,
thicknesses and the like. In various embodiments, tubular members 1
1, 13 may be flexible along their entire lengths, rigid along their
entire lengths or part-flexible, part-rigid. The members 11, 13 may
be composed of one or more metals, such as Nitinol, stainless steel
or titanium; flexible or rigid polymers, such as polyurethane,
polytetrafluoroethylene (PTFE), other fluoropolymers, PEAX.RTM.,
and/or the like; or any other suitable material or combination of
materials. In some embodiments, tubular members 11, 13 may be
rigidly fixed to one another, while in other embodiments one of the
members 11, 13 may be movable relative to the other. For example,
in one embodiment outer tubular member 11 is slidably disposed over
inner tubular member 13 so that it can retract proximally over
inner tubular member 13 and then extend back distally to its
original position.
[0038] As shown in FIG. 3, a slidable outer tubular member 11 may
allow the size of balloon 12 to be adjusted by a user. Balloon 12
may be coupled with outer tubular-member 11 at an attachment point
30 such that sliding outer tubular member 11 proximally and
introducing additional fluid or other inflating substance into
balloon 12 will cause balloon 12 to further expand. Any suitable
configuration of balloon material and attachment point 30 may be
used. In one embodiment, for example, balloon material may be
housed in a small slit or housing coupled with outer tubular member
11.
[0039] In an alternative embodiment, outer tubular member 11 may be
fixed, rather than slidable, and an outer, slidable sleeve (not
shown) may be disposed over outer tubular member 11. The outer,
slidable sleeve may be moved distally to contain part of balloon 12
and moved proximally to release part of balloon 12 to allow for
additional expansion. Allowing a user to adjust the size of balloon
12 by sliding outer tubular member 11 proximally or distally and
possibly by introducing additional inflation fluid may improve the
users ability to visualize the surgical site. Balloon expansion,
for example, may help exclude additional blood and/or push aside
surrounding tissue from the surgical site.
[0040] It may sometimes be advantageous to introduce a fluid
substance into device passage lumen 20 to cleanse devices, cleanse
balloon 12, clear an area around the surgical site and/or the like.
In one embodiment, for example, saline may be introduced proximally
with sufficient force to propel it forward (distally) through
device passage lumen 20 to "flush" lumen 20. Introduction of saline
or other fluids may be accomplished via any suitable proximal
inlet, such as a valve on a Y-connector device or the like.
[0041] Balloon 12 may have any suitable size, shape and
configuration and may be made from any suitable expandable
material. Although a toroidal balloon is shown in FIGS. 2 and 3,
alternative embodiments may include a spherical, ovoid or otherwise
shaped balloon disposed adjacent a lumen for instrument passage but
not encircling the lumen. Such an embodiment is described further
below with reference to FIG. 4. Similarly, any suitable inflation
lumen may be included in sheath 10 for expanding balloon 12. In
some embodiments, inflation lumen 22 is formed by the annular space
between outer tubular member 11 and inner tubular member 13. Thus,
inflation lumen 22 may comprise a circumferential lumen.
Alternatively, one or more tubular lumens may be disposed within
the annular space between outer tubular member 11 and inner tubular
member 13. Any means for inflating balloon 12 is contemplated
within the scope of the invention. Typically, balloon 12 is
inflated by introducing a fluid, such as saline, into balloon 12
via inflation lumen 22, although any other inflation technique or
substance may be used.
[0042] Similarly, device passage lumen 20 may have any suitable
size, diameter and the like and may be disposed in any location
through sheath 10. Thus, device passage lumen 20 may open into
aperture 15 through balloon 12, or may alternatively open adjacent
(but not through) balloon 12. Lumen 20 may allow passage of any
suitable device or devices, such as a surgical clip applier 14 for
applying clips 16, coupled with a tether 18, to a heart valve
annulus. In other embodiments, ablation devices, electrocautery
devices, suturing devices, cutting devices, and/or the like may be
passed through device passage lumen 20. Again, any and all suitable
devices are contemplated.
[0043] Sheath 10 may also include one or more visualization devices
24. In some embodiments, visualization device 24 is included as
part of sheath 10, while in other embodiments, a separate
visualization device 24 may be inserted into sheath 10 by a user.
These latter embodiments may allow, for example, a physician to use
an already-owned visualization device or other device with sheath
10. Visualization device 24 itself may comprise any suitable
device, such as a fiber optic device, an ultrasonic device, a
charge coupled device, a camera, or the like. In embodiments where
visualization device 24 is included, it may be coupled with sheath
10 in any suitable manner. For example, visualization device 24 may
be disposed within inflation lumen 22 in such a way that it can
move within lumen 22. In an embodiment as shown in FIGS. 2 and 3,
visualization device 24 may be movable around the circumference of
inflation lumen 22, thus encircling device passage lumen 20. Such
movement allows a user to acquire views of the surgical site from
multiple angles.
[0044] In some embodiments, multiple visualization devices 24 or a
visualization device disposed around a length of the distal end of
sheath 10 may be used to visualize the site from multiple angles.
To further enhance visualization, some embodiments may include a
central processing unit (CPU) at or near the distal end of sheath
10 for processing images captured by visualization device 24.
Processed images could then be transmitted proximally along sheath
10 to provide images to the user. For example, in one embodiment
visualization may be achieved using a light source and one or more
sensors or detectors disposed in a 360-degree array around an
inner, device-passage lumen, the light source and the detectors
disposed at the distal end of a visualization device. The sensors
may then be coupled with a charge coupled device (CCD) disposed
near the distal end of the device, the CCD being coupled with a
wire that transmits data proximally along the visualization
device.
[0045] Although visualization device 24 is shown with a distal
portion and optical element 26 extending into balloon 12, in other
embodiments optical element may be flush with, or recessed into,
the distal end of inner tubular member 13 and/or outer tubular
member 11. Thus, there is no requirement that any visualization
member extend into balloon 12. Such a configuration may be
advantageous, in that optical element 26 may be positioned closer
to clip applier 14 or other devices and closer to the surgical
site. If an angled optical element is used, it may be further
advantageous to have the optical element facing centrally towards
the surgical instrument(s) (or in another direction towards the
instrument(s) in other embodiments).
[0046] Referring now to FIG. 4, an alternative embodiment of a
sheath 40 includes an outer tubular member 42, an inflation lumen
44, a balloon 46, a visualization device 48, and a device passage
lumen 50 for allowing passage of one or more surgical instruments
52. In contrast to the earlier described embodiment, inflation
lumen 44 does not encircle device passage lumen 50, but instead the
two lumens are adjacent one another. The two lumens may be placed
at any suitable location through sheath 40 and may exit sheath 40
at any suitable locations, though preferably visualization device
48 will be relative close to device passage lumen 50 to allow for
direct visualization of any surgical instruments passed through the
lumen 50. In an alternative embodiment, multiple inflation lumens
44, multiple balloons 46 and/or multiple visualization devices 48
may be included. As with the previously described embodiments, some
sheaths will include one or more visualization devices 48 while
others will simply allow for insertion of a user's visualization
device.
[0047] Methods of the present invention generally involve first
advancing sheath 10, 40 to a location in the heart for performing a
minimally invasive heart procedure, such as a mitral or tricuspid
valve repair. Next, expandable balloon 12, 46 is inflated and
visualization device 24, 48 is used to visualize an area within the
heart, locate an area for performing the surgical procedure, etc.
The minimally invasive procedure may then be performed, using one
or more instruments 14, 52 extending through device passage lumen
20, 50. During the procedure, real-time visualization may be
acquired via visualization device 24, 48. Even before the
procedure, visualization device 24, 48 may be used to assess the
surgical site, locate a particular structure such as a mitral valve
annulus, and reposition sheath 10, 40 for better access to the
site. In many embodiments, visualization device 24, 48 may be moved
within sheath 10, 40 and/or multiple visualization devices may be
used to acquire images from different perspectives and angles.
Multiple surgical instruments may be inserted and removed through
sheath, various visualization devices may be inserted and removed,
adjustments to the size of balloon 12, 46 may be made, and/or the
like. In some embodiments, the physician may also flush one or more
portions of sheath with a fluid passed through one of the sheath's
lumens. Any other suitable method steps may be added, steps may be
skipped or combined, and or alternative steps may be substituted
without departing from the scope of the invention.
[0048] Although various embodiments of the present invention have
been described fully above, this description is for exemplary
purposes only and should not be interpreted to limit the scope of
the invention. For example, various alterations, additions,
substitutions or the like may be made to embodiments described
above without departing from the scope of the invention. Therefore,
none of the foregoing description should be read to limit the scope
of the invention as it is defined in the following claims.
[0049] Any and all patents, applications and printed publications
mentioned above are hereby incorporated by reference.
* * * * *