U.S. patent application number 15/009642 was filed with the patent office on 2016-05-26 for method and apparatus for transapical access and closure.
The applicant listed for this patent is VasoStitch, Inc.. Invention is credited to Amir Belson, Phillip Charles Burke, Eric Thomas Johnson, Bauback Safa.
Application Number | 20160143636 15/009642 |
Document ID | / |
Family ID | 45371858 |
Filed Date | 2016-05-26 |
United States Patent
Application |
20160143636 |
Kind Code |
A1 |
Belson; Amir ; et
al. |
May 26, 2016 |
METHOD AND APPARATUS FOR TRANSAPICAL ACCESS AND CLOSURE
Abstract
Methods and apparatus for providing transapical access to a
heart chamber for performing an intra cardiac procedure are
described. The apparatus include a helical needle driver, a
dilator, a straight access needle, and optionally a guidewire.
After entering the heart chamber with the straight access needle,
the helical needle driver is used to place a helical suture within
the myocardium. After removing the needle driver, the dilator is
advanced through the pre-placed helical suture, dilating both a
passage and the circumscribing suture. After performing procedure,
the pre-placed suture may be closed by proximally retracting an
external end of the suture.
Inventors: |
Belson; Amir; (Los Altos,
CA) ; Burke; Phillip Charles; (Pala, CA) ;
Johnson; Eric Thomas; (Temecula, CA) ; Safa;
Bauback; (San Francisco, CA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
VasoStitch, Inc. |
Los Altos |
CA |
US |
|
|
Family ID: |
45371858 |
Appl. No.: |
15/009642 |
Filed: |
January 28, 2016 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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13169454 |
Jun 27, 2011 |
9277915 |
|
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15009642 |
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61398485 |
Jun 26, 2010 |
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61402042 |
Aug 23, 2010 |
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Current U.S.
Class: |
606/223 |
Current CPC
Class: |
A61B 2017/06052
20130101; A61B 2017/3405 20130101; A61B 17/0469 20130101; A61B
2018/00392 20130101; A61B 2017/06176 20130101; A61B 2017/00575
20130101; A61B 2017/00243 20130101; A61B 2017/06076 20130101; A61B
2017/00663 20130101; A61B 2017/0472 20130101; A61B 2017/0243
20130101; A61B 2017/06042 20130101; A61B 2017/0417 20130101; A61B
17/0482 20130101; A61B 2017/3458 20130101; A61B 17/3421 20130101;
A61B 17/06 20130101; A61B 2017/00247 20130101; A61B 17/3403
20130101; A61B 2017/3488 20130101; A61B 2017/3427 20130101 |
International
Class: |
A61B 17/04 20060101
A61B017/04 |
Claims
1. A system for establishing transapical access through myocardial
tissue to a heart chamber, said system comprising: a cylindrical
shaft having a distal end, a proximal end, and a central passage
extending between said ends; a helical needle coupled to the distal
end of the shaft; suture releasably carried by the helical needle;
and a dilator having a width greater than that of the shaft, said
dilator being adapted to be advanced over or in exchange for the
shaft to enlarge a passage through the suture which is left in
place through the myocardium.
2. A system as in claim 1, further comprising a sheath for
accessing the pericardium over an apical region of the heart
through an intercostal access site, wherein the cylindrical shaft
is adapted to be advanced through the sheath.
3. A system as in claim 1, further comprising a sheath for
accessing the pericardium over an apical region of the heart
through a subxiphoid approach, wherein the cylindrical shaft is
adapted to be advanced through the sheath.
4. A system as in claim 1, wherein the helical needle is fixedly
attached to the distal end of the cylindrical shaft so that the
needle is advanced through tissue by rotating the shaft.
5. A system as in claim 1, further comprising a driver for rotating
the helical needle relative to the cylindrical shaft to advance the
helical needle through tissue.
6. A system as in claim 1, wherein the helical needle is hollow and
the suture is received in the needle.
7. A system as in claim 1, wherein the suture carries barbs along a
distal region, wherein the barbs are adapted to self-deploy to
anchor in myocardial tissue as the helical needle is withdrawn.
8. A system as in claim 1, wherein the suture carries a T-bar to
anchor in a heart chamber as the helical needle is withdrawn.
9. A system as in claim 1, further comprising a straight needle for
initially accessing the heart chamber through the myocardium.
10. A system as in claim 9, wherein the cylindrical shaft and
helical needle are adapted to be advanced over the straight
needle.
11. A system as in claim 9, wherein the needle is adapted to
position a guidewire through the myocardium and the cylindrical
shaft and helical needle are adapted to be advanced over the
guidewire.
12. A system as in claim 1, wherein the dilator has a threaded
exterior to facilitate advancement through tissue.
13. A system as in claim 1, wherein the dilator comprises an outer
sleeve and an inner obturator, wherein the obturator can be removed
to leave the sleeve in place in a dilated tissue tract.
14. A system as in claim 13, wherein the sleeve includes a
hemostatic valve.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. patent application
Ser. No. 13/169,454 (Attorney Docket No. 39277-704.201, now U.S.
Patent No. ______), filed Jun. 27, 2011, which claims the benefit
of prior provisional application no. 61/398,485, filed on Jun. 26,
2010, and of prior provisional application no. 61/402,042, filed on
Aug. 23, 2010, the full disclosures of which are incorporated
herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates generally to medical apparatus
and methods. More particularly, the present invention relates to
methods and apparatus for providing transapical access to a heart
chamber to facilitate performing various procedures within the
heart chamber, such as heart valve replacement, valve repair,
atrial septum repair, aneurysmectomy, and the like.
[0004] Heart valve replacement and repair on beating hearts are
typically performed via a transvascular or a transapical approach.
Of particular interest to the present invention, transapical access
is typically established via an intercostal incision and placement
of a relatively large cannula to provide access to the apex of the
heart. Conventional surgical tools are then used through the
cannula to form an incision into the heart to allow passage of the
interventional tools used for the heart valve replacement, repair,
or other procedure. Frequently, a purse string suture is pre-placed
at the site of the incision to facilitate closure after the
procedure is complete.
[0005] The need to use conventional surgical tools for making the
incision through the apical region into the heart chamber requires
that a relatively large access port be placed through the
intercostal space, typically between the fourth and fifth ribs. The
incision is typically 4 or 5 cm in length, and such incisions in
the abdomen are very painful to the patient.
[0006] For these reasons, it would be desirable to provide improved
apparatus and methods for both accessing a heart for transapical
penetration and for closing the penetration after the related
procedure has been completed. Such apparatus and methods would
preferably require a smaller intercostal incision than has often
been necessary in the past, and in particular, it would be
desirable if the incision were below 5 cm, preferably below 4 cm,
and still more preferably below 3 cm, or less. Methods and
apparatus should further provide for both simplified access and
closure protocols, should present minimum risk to the patient, be
economical, and be relatively uncomplicated for use by the
physician. At least some of these objectives will be met by the
inventions described below.
[0007] 2. Description of the Background Art
[0008] U.S. Patent Publ. Nos. 2011/0015728; 2011/0004235; and
2009/0287183 describe devices for transapically accessing a heart
chamber for performing valve replacement and other procedures. U.S.
Patent Publ. No 2010/0268253 describes a self-closing structure
that can be disposed about a transapical access site. U.S. Pat. No.
4,204,541, describes a helical needle for performing vertical
suturing in tissues including cardiac and live tissue. U.S. Pat.
Nos. 7,758,595; 7,637,918; 5,545,148; and 5,356,424; and U.S.
Patent Publ. Nos. 2009/275960; 2008/275473; 2006/253127; and
2006/212048 describe other suturing devices with helical
needles.
SUMMARY OF THE INVENTION
[0009] In a first aspect of the present invention, a method for
transapical access to a heart chamber comprises advancing a helical
needle through the myocardium to position a suture through an
apical region of the heart, withdrawing the helical needle leaving
the suture in place in the myocardium in a helical pattern, and
thereafter dilating a passage through the helical suture into the
heart chamber. The pre-placed suture is then available for closing
subsequent incisions into the heart by simply drawing proximately
on the suture to close such incisions. The suture is typically
self-anchoring, e.g. having anchoring barbs or a T-bar at or near
its distal end, and placement can be accomplished using relatively
small tools, typically through an intercostal incision below 3 cm,
often below 2 cm, and in some cases below 1 cm. Methods are also
suitable for performing on a beating heart, although they could be
used in stopped heart procedures as well. In exemplary embodiments,
tension is maintained on the pericardium to stabilize the heart
while the helical needle is being advanced and/or a dilator is
being advanced through the helical suture (described in more detail
below).
[0010] In an exemplary embodiment of the method of the present
invention, the helical needle is first passed through the
pericardium surrounding the heart, and the helical needle is then
drawn proximately to tension the pericardium and stabilize the
heart. The helical needle is then advanced into the myocardium
while the tension is maintained on the pericardium. In addition or
as an alternative to using the helical needle for applying traction
on the pericardium, a shaft or other component of the access tool
could also be provided with barbs, expanding elements, or the
components suitable for engaging the pericardium and applying
traction while the needle is being advanced.
[0011] In most procedures, prior to introducing the helical needle,
a straight needle will be advanced through the apical region of the
heart to establish an initial tissue tract through the myocardium
and to confirm the correct entry point and orientation. Optionally,
the needle may be used to place a guide wire, but usually the
needle itself will be used as a guide for the introduction of the
helical needle deployment device, as described in more detail
below. In such cases, the needle may have to have a proximal hub
that can be removed prior to advancement of the helical needle
assembly thereover. Alternatively, the needle shaft could be long
enough to allow the helical needle assembly to be pre-loaded on the
straight needle prior to accessing the heart chamber.
[0012] In many cases, the present invention will use a single
helical needle in order to place a single helical suture. In other
embodiments, however, it may be desirable to deploy multiple
helical needles, usually simultaneously using the same needle
deployment shaft. In some instances, two or more helical needles
may be coaxially nested with one helical needle having a smaller
diameter and being disposed radially inwardly of an outer helical
needle. In other instances, the two or more helical needles may be
located in a common cylindrical envelope. In such cases, the
needles may have penetrating tips which are rotationally offset
and/or axially offset from each other.
[0013] The suture will usually be placed within the myocardium and
will not extend into the heart chamber (beyond the myocardium). In
such cases, use of a suture having self-deploying barbs at its
distal end will be particularly useful. The barbs project partially
outside of the needle as the needle is rotationally advanced into
the tissue. As soon as the rotational advancement of the helical
needle is stopped and reversed, however, the barbs will anchor in
the tissue and hold the distal end of the suture in place as a
helical needle is counter-rotated and removed from the tissue. In
other instances, however, it may be desirable to advance the suture
all the way into the heart chamber. In such cases, some other
self-deploying anchor, such as a T-bar will find use.
[0014] Methods for establishing transapical access in accordance
with the present invention will find use with a variety of
intracardiac procedures that may be performed on beating hearts. In
such procedures, one or more tools are introduced through the
dilated passage which has been formed through the myocardium while
the helical suture remains in place surrounding the tool as the
tool is advanced. A cardiac procedure will be performed with the
tool, and the tool(s) then removed from the dilated passage after
the procedure has been completed. After the tools and any devices
used for access have been removed, the dilated passage may be
closed by drawing on the suture in a proximal direction, closing
the helical suture loops which were pre-placed as described above.
The methods herein are suitable for a wide variety of intracardiac
procedures including valve replacement, valve repair, left atrial
appendage closure, cardiac oblation, closure of an atrial septal
defect, closure of a patent foramen ovale, and the like.
[0015] In a second aspect of the present invention, a system for
establishing transapical access through myocardial tissue is
provided. The system comprises a helical needle driver having a
cylindrical shaft having a distal end, a proximal end, and a
central passage extending between said ends. A helical needle is
coupled to the distal end of the shaft, and suture is releasably
carried by the helical needle. The system further comprises a
dilator having a width greater than that of the cylindrical shaft,
where the dilator is adapted to exchanged for the helical needle
driver to enlarge a passage through the helical suture which is
left in place in the myocardium. Usually, the dilator will be
advanced over the straight needle or optionally over a guidewire
deployed by the straight needle. The system may optionally further
include a sheath or a trocar for establishing access to the
pericardium from an intercostal access site or optionally from a
subxiphoid access site.
[0016] In a simpler embodiment, the helical needle driver may
include just the helical needle (or multiple needles as described
below in connection with the methods of the present invention),
fixedly attached to the distal end of the cylindrical shaft so that
the needle is advanced through the tissue by rotating the entire
cylindrical shaft. Preferably, however, the helical needle driver
will further comprise a mechanism for rotating the helical needle
relative to the cylindrical shaft to advance the helical needle
through tissue and relative to the shaft itself. An exemplary
driver mechanism will comprise a coaxial inner cylinder or tube
which carries the helical needle(s) at its distal end. The needles
may then be advanced relative to the outer cylindrical shaft by
rotating and advancing the intertubular shaft relative to the outer
shaft, for example using a threaded drive assembly in the handle of
the shaft assembly.
[0017] In most instances, the helical needle is hollow and the
suture is received into the hollow passage of the needle at least
over a portion of the needle length. In other instances, however,
it may be possible to serve or wrap the suture over the exterior of
the needle and/or within recesses formed in the needle surface
(where the needle need not be hollow). For example, the suture may
be wrapped around the exterior surface of the needle so that the
suture is left in a loose pattern within the myocardium, with
excess suture length available for expansion or elongation when the
suture is radially expanded by the dilator.
[0018] The system may optionally include other components, such as
the straight needle used for initially accessing the heart chamber
through the myocardium, a guidewire to optionally be placed using
this straight needle, and the like. In another case, the
cylindrical shaft of the needle deployment tool will be advanced
over the needle and/or over the guidewire in order to establish the
initial penetration through the myocardium. Another option is the
use of a catheter or other guiding apparatus having a balloon or
other anchor at its distal end where, after the insertion of its
distal tip to the ventricle, the anchor will be deployed and the
guiding apparatus retracted to provide a counter force for the
dilator insertion.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 illustrates a system for establishing transapical
access to a heart chamber constructed in accordance with the
principles of the present invention and including a helical needle
driver, a dilator, a straight needle, and optionally a
guidewire.
[0020] FIGS. 2A and 2B illustrate the helical needle driver of FIG.
1 in detail, with the helical needle retracted in FIG. 2A and the
helical needle advanced in FIG. 2B.
[0021] FIGS. 3A and 3B illustrate a barbed suture anchor and a
T-bar suture anchor, respectively, emerging from distal end of a
helical needle.
[0022] FIGS. 4A and 4B illustrate a dual needle embodiment having
the sharpened needle tips axially offset.
[0023] FIGS. 5A and 5B illustrate a dual needle embodiment having
the sharpened needle tips being 180.degree. offset.
[0024] FIGS. 6A and 6B illustrate a dual needle embodiment having a
larger diameter outer helical needle and a smaller diameter inner
helical needle.
[0025] FIGS. 7A-7E illustrate exemplary dilator contractions in
accordance with the principles of the present invention.
[0026] FIGS. 8A-8J illustrate an exemplary transapical access
procedure and intervention performed in accordance with the
principles of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0027] Referring to FIG. 1, a system 10 constructed in accordance
with the principles of the present invention includes a helical
needle driver 12, a dilator 14, a straight needle 16, and
optionally a guidewire 18. The components of the system will
typically be packaged together in conventional packaging, such as
plastic trays, sterilized bags, boxes, and the like. The relative
dimensions of each of the components will be selected to be
compatible with each other. For example, both the helical needle
driver 12 and dilator 14 will be sized to be advanced over either
the needle 16 (in embodiments where the needle will be used as the
guide for introducing these tools through the myocardium), or over
the guidewire 18 (in embodiments where the driver 12 and dilator 14
will be advanced over the guidewire).
[0028] Referring now to FIGS. 2A and 2B, the helical needle driver
12 comprises a shaft assembly 20 having a distal end 22 and a
proximal end 24. A drive handle 26 is attached to the proximal end
24 of the shaft assembly 20 and includes an inner threaded body 28
(FIG. 2A) and an outer rotatable member 30. The outer rotatable
member 30 can be rotated over the inner threaded body 28 so that a
helical needle 36 can be selectively retracted and advanced as
shown in FIGS. 2A and 2B, respectively.
[0029] The inner threaded body 28 of the drive handle 26 is fixedly
attached to an outer cylindrical tube 32 of the shaft assembly 20
while the outer rotatable member 30 is attached to an inner tubular
member 34 (FIG. 2A). In this way, rotation of the outer rotatable
member 30 over the inner threaded body 28 both rotates and advances
(or retracts) the helical needle 36 which is fixedly attached to a
distal end of the inner tubular member 34. Although shown as a
simple helical needle, the needle in the helical needle driver can
have any of the configurations shown in FIGS. 3A/B through 6A/B
described below.
[0030] The helical needle driver 12 also includes a central tube 38
which extends the entire length thereof and which provides a
central passage way or lumen for advancement of the driver over the
straight needle 16 and/or guidewire 18, as described in more detail
below.
[0031] Referring to FIGS. 3A and 3B, suture 40 will typically be
stowed or held within a hollow passageway through at least a distal
portion of the needle 36. The suture will extend out of a small
hole or port 42 disposed near the sharpened tip 44 of the needle.
The suture will have an anchor formed at or over its exposed end.
The anchor may be a barbed structure 48, as show in FIG. 3A, a
T-Bar structure 50, as shown in FIG. 3B, or any one of a variety of
other structures which allow the suture to be advanced into the
tissue and which anchor within the tissue when the needle is
counter-rotated and withdrawn from the tissue. The suture may be
configured and/or deployed to accommodate expansion as the dilator
is advanced through the helical "cage" formed after the suture is
deployed. For example, the suture could be "stretchable" along its
length so that the diameter of the helical cage can increase as the
dilator is advanced. Alternatively, excess suture length can be
stowed in and/or over the helical needle so that extra lengthing
capacity is provided when the suture is left in the tissue.
[0032] Referring now to FIGS. 4A/B through 6A/B, a variety of dual
needle configurations will be described. An advantage of utilizing
two, three, or even more helical needles is that a greater density
of suture can be left in place in order to provide for tighter
closure and constriction of the dilated passage formed through the
myocardium. In FIGS. 4A/B, a pair of helical needles 16, 62 are
nested so that they lie within the same cylindrical envelope while
having distal tips 64 and 66, respectively, which terminate in an
axially spaced-part pattern. Needles 70, 72, as shown in FIGS. 5A
and 5B, are also nested so that they lie in the same cylindrical
envelope, but the sharpened distal tips 74, 76, respectively,
terminate at locations 180.degree. opposed to each other. As a
third alternative, helical needles 80, 82, as illustrated in FIGS.
6A/B, may be arranged in a cylindrically nested configuration where
an outer helical needle 80 has a larger diameter than an inner
helical needle 82. The sharpened distal tips may terminate
180.degree. in opposition as illustrated, or could terminate in
axially spaced-apart configurations (not illustrated).
[0033] Referring now to FIGS. 7A through 7C, a dilator 14
preferably comprises a body formed from an elastomeric or other
compressible material over at least its distal portion. For
example, the elastomeric material may be formed into an outer
tubular component 90 formed over an inner rigid tubular support 92,
shown in FIG. 7A. The tube has an inner lumen 93 suitable for
receiving and advancement over the access needle and/or a guidewire
present in the initial tissue tract being dilated. Cutting blades
94 may be attached to a distal end of the inner support tube 92,
and such blades may be recessed within protective grooves 96 as
shown in FIG. 7B (as shown for a two-bladed configuration) and FIG.
7C (as shown for a four-bladed configuration). In this way, the
cutting edges of the blades 94 will be protected from inadvertently
cutting tissue but will be exposed when the dilator tip is engaged
against particularly strong tissue or membranes which resist
expansion and will require cutting, such as the pericardium.
Optionally, the obturator may comprise an outer sleeve 93 and
removable obturator 95 (FIG. 7D) or may have external threading 97
(FIG. 7E) to assist in advancement through the myocardium.
[0034] The blades 94 need to have widths which span the entire
diameter of the dilator 14. For example, a typical dilator diameter
will be 1 cm, and the blades will typically span only 2 mm to 6 mm.
Alternatively or additionally, the dilator may have external
threads which allow the dilator to be rotated about its axis to
enhance advancement through the tissue tract.
[0035] Referring now to FIGS. 8A through 8J, an exemplary protocol
for transapically accessing a heart chamber and performing an intra
cardiac procedure according to the principles of the present
invention will be described. The relevant patient anatomy is
illustrated in FIG. 8A where a transapical region TA of a patient's
heart H is protected behind the patient's ribs. Access will
generally be performed through the intercostal space between rib R4
and rib R5.
[0036] Initially, the straight needle 16 will be penetrated
intercostally between ribs R4 and R5 so that the sharpened tip of
the needle can enter the heart at the transapical region TA, as
shown in FIG. 8B. Usually, the straight needle will be passed
through a small intercostal incision, e.g., less than 3 cm, usually
less than 2 cm, and often about 1 cm. To assist in guiding, the
straight needle may incorporate ultrasonic or optical imaging.
Alternatively, a thoracoscope or other endoscope could be deployed
through a separate incision to allow visualization.
[0037] After advancing the needle through the myocardium into the
left ventricle of the heart, the needle hub 17 will be removed and
the helical needle driver 12 will be advanced over the needle 16,
as shown in FIG. 8C. The shaft assembly 20 of the needle driver 12
will be advanced until the distal tip of the shaft engages the
pericardium surrounding the myocardium of the heart.
[0038] Referring now to FIG. 8D, the helical needle 36 will be
advanced from the distal end of the shaft assembly 20 to initially
penetrate the pericardium P. Once the needle has penetrated the
pericardium, the helical needle driver 12 will be proximally
retracted to apply tension to the pericardium which will help
stabilize the heart and facilitate needle entry into the heart.
[0039] As illustrated in FIG. 8E, the helical needle 36 may be
rotated and advanced into the myocardium M while the pericardium P
remains under traction. Straight needle 16 also remains in place to
help guide the helical needle 36.
[0040] Preferably, the needle 36 will not be advanced fully into
the left ventricle and, instead, needle rotation will stop and be
reversed in order to leave the helical suture in place with the
barb anchor 48 within the myocardium as show in FIG. 8F. At this
point, the helical needle driver will be completely withdrawn,
leaving the straight access (guiding) needle 60 and helical suture
40 in place.
[0041] Next, as shown in FIG. 8G, the dilator 14 will be advanced
over the needle 16 until its distal tip reaches the pericardium P.
As the dilator 14 is advanced through the pericardium, the recessed
blades 94 will be exposed as the elastomeric material surrounding
them is compressed by the pericardium. The blades 94 help the
dilator 14 pass through the pericardium, and the dilator is then
able to enter the myocardium M as shown in FIG. 8H. As the
myocardium M is not as fibrous and difficult to penetrate as the
pericardium is, the elastomeric material will recover from
compression and the blades 94 will again be recessed within the tip
of the dilator 14 as the tip advances into the left ventricle of
the heart. The blades 94 are optional, particularly if the
pericardium is pre-cut prior to advancing the dilator therethrough.
Blades are usually not needed to advance the dilator through the
myocardium.
[0042] As the dilator 14 passes through the helical suture 40, the
suture is radially expanded. Typically, extra lengths of suture
will be left in place by the helical needle in order to facilitate
radial expansion. For example, the suture 40 may be stowed within a
central passage of the needle in a serpentine or compacted
configuration where tension on the suture will extend its length.
Further optionally, the needle, guidewire, or other guiding
apparatus (not illustrated) may be provided with a balloon or other
deployable anchor to allow a counter traction on the myocardium as
the dilator is advanced.
[0043] After the dilator 14 has been passed through the myocardium
M, as shown in FIG. 8H, the dilator will be removed and a working
cannula WC having a hemostatic value HV is placed over the needle
16 and the needle removed as shown in FIG. 81. The working cannula
provides access for working tools intended to perform any
particular intra cardiac procedure desired. An exemplary tool T is
illustrated, but it will be appreciated that specific tools will be
associated with specific procedures. Optionally, the working
cannula can be part of the dilator where a central member
(obturator) of the dilator is removed to leave an outer sleeve in
place as the cannula.
[0044] Finally, after the intra cardiac procedure is complete and
the working cannula WC and all tools T removed, the suture 40 may
be proximately retracted to close the helical suture loops within
the myocardium to close the incision I as shown in FIG. 8J. The
suture could be tied off, but more usually, a suture lock 100 will
be advanced over the suture to hold the suture loops and prevent
the incision I from reopening.
[0045] While the above is a complete description of the preferred
embodiments of the invention, various alternatives, modifications,
and equivalents may be used. Therefore, the above description
should not be taken as limiting the scope of the invention which is
defined by the appended claims.
* * * * *