U.S. patent application number 13/038149 was filed with the patent office on 2011-09-01 for aneurysm sensing devices and delivery systems.
This patent application is currently assigned to Endovascular Technologies, Inc.. Invention is credited to Peter S. Brown, Albert K. Chin, Arnold M. Escano, Gregory W. Fung, Rasean L. Hamilton, Juan I. Perez, Richard Rapoza, Shuji Uemura, Michael F. Wei, Arlene S. Yang.
Application Number | 20110213413 13/038149 |
Document ID | / |
Family ID | 43805830 |
Filed Date | 2011-09-01 |
United States Patent
Application |
20110213413 |
Kind Code |
A1 |
Brown; Peter S. ; et
al. |
September 1, 2011 |
ANEURYSM SENSING DEVICES AND DELIVERY SYSTEMS
Abstract
A system for gaining access to an interventional site within
vasculature through a vessel wall or other structure such as that
of a medical device. An apparatus is provided to accomplish a
sealed worksite as are sensor delivery systems including sealable
sensor devices that are adapted to be placed at the interventional
site.
Inventors: |
Brown; Peter S.; (Palo Alto,
CA) ; Chin; Albert K.; (Palo Alto, CA) ;
Escano; Arnold M.; (Santa Clara, CA) ; Fung; Gregory
W.; (San Mateo, CA) ; Hamilton; Rasean L.;
(Santa Clara, CA) ; Perez; Juan I.; (San Jose,
CA) ; Rapoza; Richard; (San Francisco, CA) ;
Uemura; Shuji; (San Mateo, CA) ; Wei; Michael F.;
(Menlo Park, CA) ; Yang; Arlene S.; (Belmont,
CA) |
Assignee: |
Endovascular Technologies,
Inc.
Santa Clara
CA
|
Family ID: |
43805830 |
Appl. No.: |
13/038149 |
Filed: |
March 1, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10962206 |
Oct 8, 2004 |
7918800 |
|
|
13038149 |
|
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|
Current U.S.
Class: |
606/213 |
Current CPC
Class: |
A61B 17/0467 20130101;
A61B 2017/306 20130101; A61B 2017/0417 20130101; A61B 2017/0419
20130101; A61B 17/00234 20130101; A61B 2017/00022 20130101; A61B
5/061 20130101; A61B 17/0057 20130101; A61B 2017/0496 20130101;
A61B 2017/00592 20130101; A61B 2017/06052 20130101; A61B 2017/00606
20130101; A61B 5/02014 20130101; A61B 2017/0404 20130101; A61B 5/00
20130101 |
Class at
Publication: |
606/213 |
International
Class: |
A61B 17/00 20060101
A61B017/00 |
Claims
1. A system comprising: an elongate member having a terminal end
configured to be placed across a wall to an interior of a body
cavity or medical device; a first member configured to extend
beyond an interior of a vessel wall; and a second sealing member
configured to engage an exterior of a vessel wall and the sensor
attached to the first sealing member.
2. The system of claim 1, further comprising a wall piercing
member.
3. The system of claim 2, wherein the piercing member is
retractable.
4. The system of claim 2, wherein the wall piercing member is
attached to and configured beyond a far end of the first
member.
5. The system of claim 1, further comprising a sensor assembly
attached to one of the first members and second sealing
members.
6. The system of claim 1, wherein the elongate tubular member is
detachable from the first and second sealing members.
7. The system of claim 1, wherein the first member includes a
sealing assembly that engages the exterior of the wall.
8. A system comprising: an elongate member having a terminal end
configured to be placed across a wall to an interior of a body
cavity or medical device; and a sensor assembly having a first part
configured to be placed within the vessel or medical device and a
second part configured to be placed exterior the vessel or medical
device.
9. The system of claim 8, wherein the elongate member releasably
receives the sensor assembly and includes a first cavity for the
first part and a second cavity for the second part.
10. The system of claim 8, wherein the sensor assembly includes a
sealing member.
11. The system of claim 8, wherein the terminal end of the elongate
member is configured to pierce a wall.
12. The system of claim 8, wherein the sensor assembly includes an
expandable portion.
13. The system of claim 8, wherein the sensor assembly includes a
wall piercing member.
14. The system of claim 8, wherein the sensor assembly includes a
coil assembly.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent
application Ser. No. 10/962,206, filed Oct. 8, 2004, the entire
contents of which are incorporated herein by reference.
TECHNICAL FIELD
[0002] This invention relates to the treatment of body lumens and,
more particularly, to the endovascular placement of medical devices
within vasculature for the purpose of repairing the same.
BACKGROUND OF THE INVENTION
[0003] Ruptured abdominal aortic aneurysms (AAA) are a leading
cause of death in the United States. Treatment options to repair
AAA include conventional open surgery and implantation of an
endovascular graft. Conventional open surgical repair of AAA
involves major abdominal surgery with associated high rates of
morbidity. Endovascular grafts have been developed to endoluminally
bypass abdominal aortic aneurysms through minimally invasive
surgery. Many patients that are unacceptable surgical risks for
open repairs are eligible for endovascular graft implantation.
Deployment of transfemoral, endovascular grafts to treat AAA is
appealing for many reasons: avoidance of an abdominal incision,
lack of aortic cross clamping, the potential for regional
anesthesia, and a shortened hospital stay.
[0004] Untreated AAA have been shown to continue to expand until
rupture, with an associated high mortality rate. Implantation of
endovascular grafts have also been associated with high
complication rates, including perioperative death, conversion to
open repair, the need for further intervention, the need for
hemodialysis, a failure to cure the AAA, and wound
complications.
[0005] The inability to obtain or maintain a secure seal between
the vessel wall and the endovascular graft is a complication unique
to endovascular aneurysm exclusion. Because the term "leak" has
been associated with aneurysm rupture following conventional
surgery, the term "endoleak" has been proposed as a more definitive
description of this complication. It is believed that persistent
endoleaks result in continued aneurysm expansion, which may
eventually lead to aneurysm rupture. Aneurysms that have been
successfully excluded have shown a tendency towards a reduction in
aneurysm diameter. Failure to properly exclude the aneurysm from
systemic arterial blood pressure keeps the patient at risk of
impending rupture. Endoleaks have been classified according to the
source of the leaks. Current classifications of endoleaks include
four categories. Type I endoleaks are "perigraft" or
"graft-related" leaks that involve a persistent channel of blood
flow due to inadequate or ineffective sealing at the ends of the
endovascular graft, or between overlapping components of a modular
system. Type II endoleaks are retrograde flow into the aneurysm sac
from patent lumbar arteries, the inferior mesenteric artery, or
other collateral vessels. Type III endoleaks result from fabric
tears, graft disconnection, or graft disintegration. Finally, Type
IV endoleaks are flow through the graft fabric associated with
graft wall porosity or permeability. It has been recognized that
preoperative patent side branches are not a good predictor of
postoperative endoleaks.
[0006] There have been a number of reported cases of aneurysm
rupture following implantation of an endovascular graft. Some of
the ruptures occurred in patients without a documented
endoleak.
[0007] A number of studies have focused on measurement of pressure
within the aneurysm sac following implantation of an endovascular
graft, both in the human patient, an animal model, or an in vitro
model. Properly implanted endovascular grafts have been shown to
reduce the pressure within the aneurysm sac while an endoleak, with
or without detectable blood flow, continues to pressurize the sac
at pressures equivalent to the systemic arterial pressure. Animal
studies utilizing a predictable rupturing aneurysm model have shown
that non-excluded aneurysms will rupture. Thrombosed aneurysm sacs
may still receive pressurization from a sealed endoleak and this
continued pressurization keeps the aneurysm at risk for
rupture.
[0008] Current methods of patient follow-up include arteriography,
contrast-enhanced spiral computed tomography (CT), duplex
ultrasonography, abdominal X-ray, and intravascular ultrasound. All
of these methods are costly and involve invasive procedures with
associated morbidity that may need to be performed in a hospital.
None of the imaging methods are completely successful in detecting
endoleaks. Therefore, the potential exists for an endoleak to go
undetected until eventual rupture. An increase in aneurysm diameter
is detectable, and should be considered an indication of endoleak.
To avoid aneurysm rupture an increase in aneurysm diameter must be
detected in a timely fashion to identify patients in need of
corrective endovascular procedures.
[0009] An endovascular graft with the ability to measure pressure
within the aneurysm sac and provide feedback to the physician could
provide acute confirmation of a procedure and identify those
patients with persistent pressurization of their aneurysm, and
subsequent risk of rupture. Some physicians are advocating that the
follow-up examinations of AAA patients focus on pressure
measurements, but that this is not currently clinically feasible.
Furthermore, follow-up examinations may be performed in the
physician's office as opposed to a hospital. Moreover, clinicians
will require method to study the pathology of post-endovascularly
treated AAA disease.
[0010] Accordingly, there exists a need for a non-invasive
measurement of pressure, as well as other pertinent parameters,
within the aneurysm sac as a means for confirming the success of a
procedure as well as identifying patients at risk for aneurysm
rupture after the endovascular graft is implanted.
[0011] However, providing devices on an endovascular graft to
facilitate the measurement of pertinent parameters poses problems.
The measurement device increases bulk, which can significantly
affect the delivery profile of the endovascular graft and increase
the force necessary to deploy the device, such as jacket or release
wire retraction forces. Thus, increased bulk is a significant issue
for an endovascular graft. Furthermore, attachment of measurement
devices to an endovascular graft may require sutures and the suture
knots not only provide increased bulk, but are also potential graft
wear points. Additionally, tissue growth around a measuring device
attached to an implanted endovascular graft may interfere with its
function and inaccurate data may result.
[0012] Therefore, what is need are alternative approaches to
obtaining information regarding the success of an aneurysm repair
procedure such as alternative approaches to gaining access to
delivering and implanting sensing devices to the repair site. The
present invention addresses these problems and other needs.
SUMMARY OF THE INVENTION
[0013] Briefly and in general terms, the present invention is
directed towards approaches to obtaining information regarding the
success of repair and aneurysm or other vascular diseases. The
present invention is also contemplated to be used to sense
condition in other areas of the body such as all types of the
body's cavities, the heart, intestines, the brain, the eye, body
ducts or the like. Sensing devices are contemplated to be deployed
in an area of a repair site to gather such information.
[0014] In one aspect, an external or extra-vascular approach is
taken to access vasculature that has been repaired. In the case of
aortic aneurysm repair, for example, a retro-peritoneal approach
can be taken. The subject vasculature is then punctured and a
sensing device is placed within vasculature at the repair site.
[0015] In one particular aspect, a vacuum cannula is provided. The
vacuum cannula includes a central lumen and is configured to
provide a working area for medical devices. In one embodiment, the
cannula includes sealing and flushing structure or devices.
[0016] Sensing devices are contemplated to be placed within
vasculature either attached or unattached to vessel walls or grafts
or other medical devices placed within a patient. When the sensors
are unattached to vessel walls or other structures, a cage can be
provided to space the sensor from anatomy or medical devices and to
protect the sensor. The sensors can also include anchors or other
devices for attachment to a vessel wall or a graft for example, as
well as substructure for releasably engaging a delivery
catheter.
[0017] In another aspect, the present invention includes a puncture
sealer that is releasably connected to a cannula or other elongate
medical device. In one embodiment, the sealer includes structure
that engages both internal and external surfaces of vasculature to
effectively seal a vessel puncture site.
[0018] In other aspects of the present invention, sealing structure
is incorporated into a sensing device that is releasable from a
delivery cannula. Various subassemblies are contemplated such as a
single or dual plug approach. The sensor itself can include a sharp
terminal end useful for accomplishing the puncturing of a vessel
wall or a graft or other medical device. The sensor can further
include mating structure, one component of which is adapted to
reside within a vessel and the other to create a seal with the
first component external the vessel or the graft device. In yet
other approaches, the sensor profile is adjustable in vivo to both
implant the sensor within a vessel as well as seal the vessel wall
or opening resulting from attaching the sensor to a medical
device.
[0019] A steerable sensor delivery catheter is also provided. The
steerable catheter includes structures for releasing the sensor
within vasculature at a location remote from a puncture site. Such
a sensor can both be deployed free-floating as well as anchored to
a vessel wall or other medical devices. Various modes of sensor
deployment are contemplated as are auxiliary structures for
anchoring sensors to vessel wall.
[0020] Other features and advantages of the present invention will
become apparent from the following detailed description, taken in
conjunction with the accompanying drawings, which illustrate, by
way of example, the principles of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] FIG. 1 is a perspective view, depicting one embodiment of a
vacuum cannula;
[0022] FIG. 2 is an end view, depicting an inferior end of the
vacuum cannula of FIG. 1;
[0023] FIG. 3 is an end view, depicting a superior end of the
vacuum cannula of FIG. 1;
[0024] FIG. 4 is a cross-sectional view, taken along line A-A of
FIG. 2;
[0025] FIG. 5 is a perspective view, depicting another embodiment
of a vacuum cannula;
[0026] FIG. 6 is an end view, depicting an inferior end of the
vacuum cannula of FIG. 5;
[0027] FIG. 7 is an end view, depicting a superior end of the
vacuum cannula of FIG. 5;
[0028] FIG. 8 is a cross-sectional view taken along line A-A of
FIG. 6;
[0029] FIG. 9 is a cross-sectional view taken along line B-B of
FIG. 6;
[0030] FIG. 10 is a perspective view, depicting a third embodiment
of a vacuum cannula;
[0031] FIG. 11 is an end view, depicting a superior end of the
vacuum cannula of FIG. 10;
[0032] FIG. 12 is an end view, depicting an inferior end of the
vacuum cannula of FIG. 10;
[0033] FIG. 13 is a cross sectional view taken along line A-A of
FIG. 12;
[0034] FIG. 14 is a perspective view, depicting a sensor equipped
with a first embodiment of a sensor cage in a contracted
configuration;
[0035] FIG. 15 is a perspective view, depicting the sensor of FIG.
14 with the sensor cage in an expanded configuration;
[0036] FIG. 16 is a perspective view, depicting a sensor equipped
with a second embodiment of a sensor cage in a contracted
configuration;
[0037] FIG. 17 is a perspective view, depicting the sensor of FIG.
16 with the sensor cage in an expanded configuration;
[0038] FIG. 18 is a perspective view, depicting a sensor having a
guidewire guide;
[0039] FIG. 19 is an end view, depicting the sensor of FIG. 18
within a delivery cannula;
[0040] FIG. 20 is a perspective view, depicting a first step in a
method of sealing a puncture site;
[0041] FIG. 21 is a perspective view, depicting a second step in a
method of sealing a puncture site;
[0042] FIG. 22 is a perspective view, depicting a third step in a
method of sealing a puncture site;
[0043] FIG. 23 is a perspective view, depicting a fourth step in a
method of sealing a puncture site;
[0044] FIG. 24 is a perspective view, depicting a superior end of a
sensor delivery and wound puncture system;
[0045] FIG. 25 is a perspective view, depicting a first step of
employing the sensor delivery and wound puncture system of FIG.
24;
[0046] FIG. 26 is a perspective view, depicting a second step
involving the sensor delivery and wound puncture system of FIG.
25;
[0047] FIG. 27 is a perspective view, depicting a third step
involving the sensor delivery and wound puncture system of FIG.
25;
[0048] FIG. 28 is a perspective view, depicting a fourth step
involving the sensor delivery and wound puncture system of FIG.
25;
[0049] FIG. 29 is a perspective view, depicting a fifth step
involving the sensor delivery and wound puncture system of FIG.
25;
[0050] FIG. 30 is a perspective view, depicting a sixth step
involving the sensor delivery and wound puncture system of FIG.
25;
[0051] FIG. 31 is a perspective view, depicting a seventh step
involving the sensor delivery and wound puncture system of FIG.
25;
[0052] FIG. 32 is a perspective view, depicting a superior end
portion of a sensor delivery system;
[0053] FIG. 33 is a perspective view, depicting a first step of
employing the sensor delivery system of FIG. 32;
[0054] FIG. 34 is a perspective view, depicting a second step of
employing the sensor delivery system of FIG. 32;
[0055] FIG. 35 is a perspective view, depicting a third step of
employing the sensor delivery system of FIG. 32;
[0056] FIG. 36 is a perspective view, depicting a fourth step of
employing the sensor delivery system of FIG. 32;
[0057] FIG. 37 is a perspective view, depicting a fifth step of
employing the sensor delivery system of FIG. 32;
[0058] FIG. 38 is a perspective view, depicting a sixth step of
employing the sensor delivery system of FIG. 32;
[0059] FIG. 38A is a perspective view, depicting a seventh step of
employing the sensor delivery system of FIG. 32;
[0060] FIG. 39 is a perspective view, depicting a superior end
portion of another embodiment of a sensor delivery system;
[0061] FIG. 40 is a perspective view, depicting a first step of
employing its sensor delivery system of FIG. 39;
[0062] FIG. 41 is a perspective view, depicting a second step of
employing its sensor delivery system of FIG. 39;
[0063] FIG. 42 is a perspective view, depicting a third step of
employing its sensor delivery system of FIG. 39;
[0064] FIG. 43 is a perspective view, depicting a fourth step of
employing its sensor delivery system of FIG. 39;
[0065] FIG. 44 is a perspective view, depicting a fifth step of
employing its sensor delivery system of FIG. 39;
[0066] FIG. 45 is a perspective view, depicting a sixth step of
employing its sensor delivery system of FIG. 39;
[0067] FIG. 46 is a cross-sectional view, depicting a first step of
employing a sensor delivery system including dual chambers;
[0068] FIG. 47 is a cross-sectional view, depicting a second step
of employing a sensor delivery system including dual chambers;
[0069] FIG. 48 is a cross-sectional view, depicting a third step of
employing a sensor delivery system including dual chambers;
[0070] FIG. 49 is a cross-sectional view, depicting a fourth step
of employing a sensor delivery system including dual chambers;
[0071] FIG. 50 is a cross-sectional view, depicting a fifth step of
employing a sensor delivery system including dual chambers;
[0072] FIG. 51 is a cross-sectional view, depicting a sixth step of
employing a sensor delivery system including dual chambers;
[0073] FIG. 52 is a side view, depicting a sensor having threaded
structures;
[0074] FIG. 53 is a cross-sectional view, depicting a first step of
employing a delivery catheter carrying the sensor of FIG. 52;
[0075] FIG. 54 is a cross-sectional view, depicting the sensor of
FIG. 52 implanted at an interventional site;
[0076] FIG. 55 is a cross-sectional view, depicting an alternative
embodiment of a delivery system incorporating threaded structures
for delivering a sensor at an interventional site;
[0077] FIG. 56 is a side-view, depicting a sensor delivery system
passed through tissue;
[0078] FIG. 57 is a side view, depicting a sensor plug of the
system of FIG. 56 implanted at an intervention site;
[0079] FIG. 58 is a side view, depicting a sensor delivery system
including a detachable tip;
[0080] FIG. 59 is a side view, depicting the detachable tip of the
system of FIG. 58 implanted at an interventional site;
[0081] FIG. 60 is an end view, depicting an access tube configured
with a plurality of clamps for use in the implantation of a sensor
device;
[0082] FIG. 61 is a side view, depicting the use of the access tube
to deliver a sensor at an implantation site;
[0083] FIG. 62 is a side view, depicting the implanted sensor of
FIG. 61;
[0084] FIG. 63 is a side view, depicting a sensor including a mesh
pad and helical coil;
[0085] FIG. 64 is a side view, depicting a delivery catheter for
the sensor of FIG. 63;
[0086] FIG. 65 is a side view, depicting an intermediate step of
employing the delivery catheter of FIG. 64 to release the device of
FIG. 63;
[0087] FIG. 66 is a cross-sectional view, depicting a sensor
delivery system including a spring ejector mechanism;
[0088] FIG. 67 is a cross-sectional view, depicting the sensor
delivery system of FIG. 66 in use;
[0089] FIG. 68 is a cross-sectional view, depicting another
embodiment of a sensor delivery system including a spring ejector
mechanism;
[0090] FIG. 69 is a cross-sectional view, depicting the deployment
of a sensor using the sensor delivery system of FIG. 68;
[0091] FIG. 70 is a cross-sectional view, depicting the sensor
delivery system of FIG. 68 in use;
[0092] FIG. 71 is a cross-sectional view, depicting a superior end
portion of a sensor delivery catheter equipped with a balloon
ejection system;
[0093] FIG. 72 is a partial cross-sectional view, depicting another
sensor deployment device;
[0094] FIG. 73 is a partial cross-sectional view, depicting use of
the sensor deployment device of FIG. 72;
[0095] FIG. 74 is a cross-sectional view, depicting an implantable
sensor equipped with locking pins; and
[0096] FIG. 75 is a cross-sectional view, depicting an implantable
sensor equipped attachment patches.
DETAILED DESCRIPTION OF THE INVENTION
[0097] While the specification describes particular embodiments of
the present invention, those of ordinary skill can devise
variations of the present invention without departing from the
inventive concept.
[0098] Referring now to the drawings which are provided for
illustration and not by way of limitations, a vacuum cannula 102 is
shown in FIGS. 1-4. As for each of the devices disclosed herein,
the vacuum cannula 102 is intended to be used in medical procedures
and can be utilized in any area of a patient's body. In one
particular aspect, the vacuum cannula is designed to be employed to
provide a working space on the exterior of any organ or lumen such
as a blood vessel. The cannula can also be employed to provide a
working space on other structures such as medical devices or
grafts. In a situation where it is desirable to gain access to an
aorta, for example, a conventional retro-peritoneal approach is
taken. A trocar or other introducer device is advanced through the
patient's tissue to provide a channel to an interventional or
implantation site.
[0099] As best shown in FIG. 1, the vacuum cannula 102 is tubular
and elongate in configuration. A superior end portion 104 is
designed to extend to an interventional site and an inferior end
portion 106 is contemplated to remain exterior a patient's body. An
internal lumen 107 extends the length of the elongate body. An
annular space 108 formed in a tubular wall 109 defining the device
extends and substantially the length of the cannula.
[0100] The superior end portion 104 can be flexible so that when
placed in contact with a body or other surface, an exterior wall
110 of the cannula 102 flares outwardly with respect to an interior
wall 111, thus producing an enlarged footprint. The inferior end
portion 106 of the cannula is equipped with a valve 112 extending
from a side wall 109 of the cannula 102 and providing fluid
communication with the annular space 108 defined by inner and outer
walls 111, 110. As most clearly seen in FIG. 4, the annular space
108 begins in an area proximate the valve 112 and extends in a
superior direction to the superior end portion 104. A terminal end
113 of the inferior end portion 106 does not embody the annular
space 108 so that a vacuum can be drawn therethrough via the valve
112 and an auxiliary pump or vacuum (not shown). The internal lumen
107 is thereby left to provide a channel for receiving medical or
other instruments to be used at the working space created by the
superior end portion 104.
[0101] It is to be recognized that while equipping the superior end
portion 104 of the cannula 102 with the flexible walls 110 allows
for the format of an enlarged footprint, the same also facilitates
improving a scaling engagement at a working site by compensating
for curvature or other irregularity in the subject surface. Thus,
the internal lumen 107 is not subject to the vacuum being drawn
through the annular space 108 and the working site is isolated from
the suction force.
[0102] In an alternate embodiment, it may be contemplated that a
cannula can be equipped with a separate additional lumen for
receiving a scope should it prove necessary to not use an internal
lumen for the advancement of such devices. With reference to FIGS.
5-9, there is shown a tubular and elongate cannula 120 having an
inferior end portion 122 and a superior end portion 124 and
including a first lumen 125 and a second lumen 126. The first lumen
125 extends a length of the cannula 120, whereas the second lumen
126 extends from the inferior end portion 122 to a point 127
proximal a superior terminal end 128 of the cannula 120. It is also
contemplated that the second lumen could extend a length of the
cannula.
[0103] In this embodiment, the cannula 120 also includes a valve
129 which is in fluid communication with an annular recess 130
formed in an outer wall 131 of the cannula 120. The cannula 120
therefore includes structure for receiving a second medical device
in the second lumen 126 which can be maintained separate from other
devices passed through the first lumen 125. The cannula also
includes a superior terminal end 128 configured to provide a
sealable work space when placed in opposition with a target
surface. Again, a vacuum can be applied by an auxiliary device via
a connection to the valve 129 to aid in the sealing engagement with
target tissue and thereby isolate the work space from the
environment.
[0104] Yet another embodiment of a cannula is shown in FIGS. 10-13.
As best seen in FIG. 10, an elongate and tubular sealing cannula
130 can include a superior end portion 132 and an inferior end
portion 134. A central lumen 135 is defined by tubular walls 136.
First 137 and second 138 valves project from an exterior surface of
the tubular wall 136 near the proximal end portion 132. One of the
first and second valves 137, 138 can be configured to be connected
to a vacuum source whereas the other of the valves can be employed
for flushing the lumen 135, or the functions of the valves can be
interchangeable.
[0105] The proximal end portion 134 of the cannula 130 is further
equipped with a seal assembly 139 including a collar 140 and a
sealing membrane 141. The seal assembly 139 operates to facilitate
the control of a working site such as by controlling blood loss
through the cannula and around a puncture or incision in
tissue.
[0106] As stated, the described cannulas can be employed in any
relevant procedure to provide a working site. One such procedure
can involve gaining access to a blood vessel such as the aorta. In
one particular aspect, it may be desirable to monitor the condition
of such a blood vessel or other organ. To do so, a sensor could be
placed in the area to be monitored using the cannulas. Such a
sensor could measure any relevant parameter such as flow, pressure,
oxygen levels or other chemical levels or substances.
[0107] Turning now to FIGS. 14-17, there are shown two embodiments
of sensors incorporating structures helping to maintain
positioning. In one embodiment (FIGS. 14 and 15), the sensor 144
has one or a plurality of hydrophilic ribbons 145 attached to
exterior surfaces (such as the ends) thereof. In one aspect, the
ribbons 145 absorb water from an environment into which it is
placed. Thus, prior to deployment, the ribbons 142 add little bulk
to the sensor 144 so that the device can be implanted in an
aneurismal sac, for example. After absorbing water from the sac,
the ribbon expands from thread-like members into fingers that
facilitate limiting movement of the sensor. Such fingers are
designed to be atraumatic to a patient's anatomy and are configured
to protect the sensor from the anatomy such as from points of
calcification.
[0108] In another embodiment (FIGS. 16 and 17), a sensor 144 can be
equipped with a nitinol wire or ribbon cage 146. The cage 146 can
be attached to an external surface of the sensor 144 such as at
ends thereof. During advancement and deployment of the sensor
within a patient's body or vasculature, the cage 146 is held tight
against external surfaces of the sensor 146. When being implanted
at an interventional or other site, the cage is permitted to expand
to its unrestrained configuration. In its unrestrained
configuration, the cage 146 both helps to hold the sensor in place
at the implantation site and to protect the sensor 144 from the
environment into which it is placed.
[0109] There may be situations where it is desirable to deliver
multiple sensors to an implantation site. It may be necessary to
deliver multiple sensors in rapid succession or it may be preferred
to provide a single platform for delivering the plurality of
sensors. For such a situation, a sensor 148 can be configured with
a guidewire ring 149. In one particular embodiment, the guidewire
ring 149 can extend the length of the sensor 148 forming a type of
spine longitudinally along the sensor 148. The sensor 141 could
also be adapted to include a single or a plurality of spaced
individual rings for receiving a guidewire. A pusher or similar
structure would then be employed to advance the sensor along the
guidewire to an implantation point.
[0110] To minimize the size of the assembly for delivering the
sensor 148 with a guidewire ring 149, the cannula 150 can be shaped
to protect the sensor 149. That is, the cannula 150 can be
irregularly shaped in cross-section. It is contemplated that this
irregular shape can be advantageous in assisting in supporting the
sensor 148 as it is advanced through the cannula 150, thereby
providing an easier pathway to the implantation or release
site.
[0111] Various methods and approaches for deploying sensors like
those described above and other sensors and medical devices will be
described below. The sealing cannulas previously presented can be
employed as necessary to provide a working space.
[0112] In the situation where it is decided that a sensor is needed
in an aneurismal sac that has been excluded or repaired by a graft
device for example, an approach and apparatus is required for
deploying a micro-sensor (or other system) that measures important
parameters providing information regarding the status of the
repaired section of vasculature. Ultrasound visualization can first
be utilized to study the area of the aneurismal sac into which the
sensor is to be placed.
[0113] Next, laparoscopic access can be relied upon to approach the
aneurysm. From the flank of the patient (preferably the left side)
approximately at a midpoint between the costal margin and iliac
crest, a 2 cm incision is made. A dissection is made through the
muscle layer into the pre-peritoneal space. A one liter balloon can
be placed in the dissected area and be inflated until the patient's
kidney is clearly visible through the balloon. After removing the
balloon, a 10 mm trocar is inserted and the area is insufflated. A
second incision the size of 1 cm is made into the cavity now formed
into which is placed a 5 mm trocar to be used for a visualization
scope.
[0114] Access for surgical tools to the area is provided by the 10
mm trocar. The dissection of the area is continued toward the
patient's spine within the pre-peritoneum until the aneurysm sac is
reached. The region of the aneurysm wall where the sensor is to be
delivered is also dissected.
[0115] In one particular approach, a purse string (not shown) is
sewn at the point of entry to the aneurismal sac. Either with the
sensor deployment device (see discussion below) itself or through
separate means, an incision large enough to accept the deployment
device is created in the aneurysm wall within the purse string
suture. Using ultrasound visualization, the location of the access
point is verified. The sensor can then be deployed within the
aneurysm sac. While tensing the purse string sutures, the
deployment tube is withdrawn. The purse string suture is then tied
off and the area is checked for leaks. Finally, the area is
deflated and the external incisions are closed.
[0116] Although the above has been described for implanting a
sensor into an aneurismal sac, similar approaches can be used to
gain access to other organs or areas of a patient's body.
Additionally, the described approach is relevant to other devices
for inserting sensors within or upon an aneurysm wall with or
without the use of sealing cannulas.
[0117] Moreover, alternate methods and structures for sealing a
puncture or incision made in an aneurysm or other body tissue may
be desirable. With reference to FIGS. 20-23, there is shown a
telescoping cannula assembly 158 including a longitudinally
extendable and retractable wire 159 and a longitudinally extendable
and retractable internal tubular cannula 160. In a situation where
the cannula assembly 158 was employed to deliver a sensor or other
component across a tissue layer 162 (while recognizing that such
delivery can be across other layers such as graft material), prior
to removing the cannula 158, a terminal end portion 163 of the wire
159 can be configured with a first collapsible umbrella or cup 164.
The first cup 164 is collapsible in an inferior direction for ease
of advancement through the cannula and includes an interior opened
in an inferior direction.
[0118] Once placed beyond the tissue (or other) layer 162, the
first cup 164 expands to an uncollapsed state (FIG. 20). The wire
159 and cannula assembly 158 are then pulled in an inferior
direction placing the first cup 164 in apposition with a far
surface of the tissue layer 162. Next, a second umbrella or cup 166
is advance by the internal tubular cannula 160 through the cannula
assembly 158. The second cup 166 is also collapsible but is
configured to collapse and includes an interior facing in a
superior direction.
[0119] The second cup 166 is continued to be advanced along the
wire 159 until the second cup 166 is placed in apposition with a
near side of the tissue layer 162. Threads, notches or ridges (not
shown) are provided on the wire for locking the two cups 164, 166
into sealing engagement about the tissue to thereby exclude a
puncture or other opening between the cups. Additionally, the wire
159 can be equipped with structure such as threads allowing the
disengagement of the first and second cups 164, 166 therefrom.
Subsequent to the disengagement of the cups 164, 166 from the wire
159, the cannula assembly 158 can be removed from the area.
[0120] Turning now to FIGS. 24-31, there is shown a sensor delivery
system 170 including ratcheting structures and flexible plugs 173,
174. The elongate sensor delivery system has a length sufficient to
extend from outside a patient's body to target tissue and includes
a terminal end 176 having a pointed cone profile that forms or
contains therein a sensor adapted to provide information regarding
a particular parameter of interest such as pressure or flow or
constituency. An outer sheath structure 177 encapsulates various
pusher mechanisms, inner shafts and the plugs 173, 174 when the
device is assembled prior to use and for advancement to target
tissue 179 (See FIG. 25). Again, in other applications, the target
can be other structure such as a graft wall or other relevant
structure.
[0121] In a first step of use, the delivery system 170 is passed
through a hole or incision 180 placed within a target tissue 179.
Although not shown, a sealed or protected working space can be
provided by one of the cannulas described above. Likewise, access
to the target tissue can be achieved laparoscopically as also
described above. After passing the device through the target tissue
179, the outer sheath structure 177 is withdrawn relative to the
terminal end 176 to expose a superior portion of a first inner
shaft 181 (See FIG. 26) which can have a generally rectangular
profile and can contain a sensing device, etc. Further withdrawal
of the sheath 177 reveals that the first shaft 181 connects the
terminal end 176 to the first flexible plug 173. Whereas various
configurations are acceptable, the first plug 173 is shown as
having a generally conical profile with a hollow interior and no
base and being configured so its interior faces in an inferior
direction.
[0122] Once the first plug 173 has been deployed beyond the target
tissue 179, the outer sheath is withdrawn further to expose and
deploy the second plug 174 on an inferior side of the target tissue
179 (FIG. 28). The second plug 174 has a similar profile to that of
the first plug 173. Being flexible, each of the first and second
plugs assume collapsed forms for advancement to the target tissue
and spring open when released from the sheath 177. Next, by
advancing an inner pusher device 182, the second plug 174 is
advanced along a second inner shaft 184 which is connected at its
terminal end to the interior of the first plug 173. The second
inner shaft 184 includes a first part of a ratcheting mechanism 185
in the form of teeth or equivalent structure that cooperates with
corresponding structure formed on the second plug 174 which forms a
second part of a ratcheting mechanism (not shown). Although any
conventional ratcheting mechanism is acceptable, such a mechanism
must be capable of accomplishing a ratcheting function through the
engagement of the pusher 182 against the second plug 174 to thereby
advance the second plug 174 into apposition with an inferior side
of the target tissue 179.
[0123] As the pusher 182 is advanced to place the second plug 174
against the target tissue 179 and the first plug 173 is drawn into
apposition with a superior side of the target tissue 179, the hole
or incision 180 is sealed within the plugs 173, 174.
[0124] A releasable connection 186 in the form of a threaded shaft
or spring release mechanism is provided at a terminal end of the
second inner shaft 185 and the second plug 174 to permit the
disengagement of the second plug from the delivery system 170. The
sensor is thereby placed within or beyond the target tissue 179 and
held in place by the first shaft 181.
[0125] In an alternative approach (See FIGS. 32-38), a sensor
delivery system 190 includes an elongate body with a retractable
sharp terminal end 191. Again, the sensor delivery system has a
length sufficient to extend from exterior a patient's body to a
target tissue or medical device placed within the patient's body. A
longitudinal retractable and extendable outer sheath 193 provides a
cover for a sensor assembly 194 and a ratcheting/sealing mechanism
195 as well as other subcomponents.
[0126] In use, the sensor delivery system 190 can be placed through
a hole or incision 196 in target tissue or other structure 197, or
the sharp retractable tip 191 can be used to create the hole or
structure 196. Again, a sealed working site can be provided by the
above-described cannula apparatus. After placing the superior end
portion of the sensor delivery system 190 beyond the target tissue
197, the sharpened tip 191 can be retracted (See FIG. 34). Next,
the outer sheath 193 is withdrawn while holding the superior end
portion stationary to reveal the sensor assembly 194 and
ratcheting/sealing mechanism 195 as well as an inner pusher member
198 and a pusher wire 199.
[0127] The pusher wire 199 is attached to an exterior of the sensor
assembly 194 opposite its sensing membrane (not shown) and is
isolated from the ratcheting/sealing mechanism 195 by an inner
tubular member 200. The push wire 199 functions to link the sensor
assembly 194 to the ratcheting/sealing membrane 198 as well as to
position an inferior end of the sensor 194 in apposition with a far
side of the target tissue 197 (See FIG. 36). The inner tubular
member 200 is then withdrawn (FIG. 37) to permit the
ratcheting/sealing member 195 to be advanced against the near side
of the target tissue 197 by the pusher member 198. The mating area
of the ratcheting/sealing member 195 is contemplated to be made
from sealing promoting materials. The pusher wire 199 is then cut
leaving the sensor assembly 194 in a position to gather the desire
data. (See FIG. 38A)
[0128] In yet another approach (See FIGS. 39-45), an elongate
sensor delivery system 202 can include a terminal end 203 having a
retractable, sharpened tip or needle 204 that can aid in puncturing
a hole 205 through target tissue 206 or other structure such as a
graft. When in its fully assembled configuration, a first
longitudinally retractable sleeve 208 extends to the terminal end
203 and upon withdrawal (See FIGS. 42 and 43) exposes a housing 209
that houses the sensor assembly. In one contemplated embodiment,
the housing 209 can be made from nitinol and include expanding
fingers (not shown) which are configured to engage a far side of
the target tissue.
[0129] Once the first retractable sheath 208 is fully withdrawn, a
collar 210 equipped with one component of a conventional ratcheting
mechanism cooperating with an inferior portion 211 of the housing
209 can be advanced until a superior end 212 of the collar 210
engages a near side of the target tissue 206 and is locked in
place. To accomplish this advancement of the collar 210, the
delivery assembly 202 can be equipped with a second longitudinally
moveable sleeve 214. Moreover, it is intended that the superior end
212 of the collar 210 include sealing promoting materials that
achieve closure of the puncture site 205. A conventional releasable
engagement (such as a threaded or spring release) between the
sensor having 209 and the remainder of the delivery apparatus 202
allows for the complete removal of the delivery apparatus from the
interventional site.
[0130] A dual chamber sensor delivery system 210 (See FIGS. 46-51)
can also be employed to affix a sensor 212 to a far side of a
target tissue 213 or a graft wall, for example. The dual chamber
delivery system 210 has an elongate profile and a pointed terminal
end portion 214. A retractable sleeve 215 encases a main catheter
component 216 including a first 217 and a second chamber 218 spaced
longitudinally along a common side of superior portion of the main
component 216.
[0131] When assembled, configured within the first chamber is a
first sensor assembly component 220 carrying the sensor 212. A
second sensor assembly component 222 is similarly configured within
the second chamber. Attached to a side of the first sensor assembly
component 220 is a wire 224 which is threaded through a bore
passing through the second sensor assembly component 222 and
extends in an inferior direction to an operator through an elongate
tubular member 226. The elongate tubular member 226 is
longitudinally movable with respect to the retractable sheath 215
and is contained within the sheath 215 along side the main catheter
216 (See FIG. 48). Additionally, each sensor component includes
teeth or other tissue engagement structure 227 that aids in
affixation to the target tissue 213 (FIG. 50) as well as internal
silicone seals 229 (FIG. 51) for closing the puncture site 228 and
seal promoting features.
[0132] In use, the dual chamber sensor delivery system 210 is
advanced from outside a patient's body to within the patient to the
target tissue or other wall structure 213. The system 210 is passed
through a hole or puncture site 228 (See FIG. 46) formed by the
system 210 or any of the other previously described structures so
that the first sensor assembly component 220 resides on the far
side of the target tissue and the second sensor assembly 222
component is on the near side. The sheath 215 is then withdrawn to
expose the sensor components 220, 222 (FIG. 47) and an ejection
wire 230 made from nitinol or other suitable material is
manipulated to cause the sensor component 220, 222 to be ejected
from the first and second chambers 217, 218, respectively.
[0133] Next, the main catheter 216 is rotated to clear the sensor
components 220, 222 from the chambers 217,218 while the relative
positioning of the elongate tubular member 226 housing the wire 224
is maintained (FIG. 48).
[0134] Thereafter, the main catheter 216 is withdrawn and the
elongate member 226 is advanced (FIGS. 49 and 50) to cause the
first and second sensor assembly components to be placed in
opposition with opposing sides of the target structure 213. When so
positioned, the wall engaging structure 227 of the sensor
components aid to permanently affix the devices against the target
structure, the second component 222 acting as a locking plug.
Moreover, by applying a sufficient withdrawal force upon the wire,
the silicone seal 229 of the first sensor component is drawn into
and fills one side of the puncture site 228 and by applying
sufficient forward force to the elongate member 226, the silicone
seal 229 of the second sensor component fills another side of the
puncture site. Finally, the wire 224 is severed or otherwise
released from engagement to the first sensor assembly component
220, leaving the sensor 212 permanently in place at the target site
213. The main catheter 216 and elongate tubular member 226 are of
course removed from the patient and any incisions are closed.
[0135] Turning now to FIGS. 52-54, there is shown a threaded sensor
assembly 230 and a delivery catheter 232 therefor. In operation,
the threaded sensor 230 performs something like a dry-wall nut and
the delivery catheter 232 like a fastener. The threaded sensor
assembly 230 includes a threaded superior end portion 234, an
expandable mid-section cage 236, and an inferior portion 238. An
internal bore extends through the device providing a space for a
screw 240 running through an outer sheath 242 of the delivery
catheter 232 (Shown retracted in FIG. 53). Also, a sensing device
244 is placed or affixed to one rib 245 of the expandable cage 236
and fuzz material or rubber or plastic 246 material can be attached
to the body of the threaded sensor assembly 230. Various alloys or
plastic materials can be used for the sensor assembly body or
carrier which can also be coated with a drug for the delivery of
the same.
[0136] Whether simply plugging a puncture 247 or for the purpose of
placing a sensor adjacent target tissue or other structure or
medical device 248, the delivery catheter 232 is placed in the
vicinity of the target and then through the puncture or opening 247
therein. Once the superior end portion 234 and midsection 236 are
placed beyond the far side of the target, the sheath 240 is
withdrawn to expose the sensor assembly 230. Next, the catheter 232
is held longitudinally stationary while the internal screw device
240 is rotated to thereby expand the midsection cage 236.
[0137] This action is continued until the ribs 245 are collapsed
against the far side of the target structure, the rear side of the
tissue being engaged by a terminal end 250 of the inferior portion
238 (which can be flanged or include a collar) of the sensor
assembly 230. A seal is created at the puncture site via the body
of the sensor assembly 230 as well as the fuzzy or other material
247 attached to the sensor body. Release of the sensor assembly 230
from the catheter can be accomplished by rotating the screw device
in a direction opposite to that which causes the expansion of the
sensor body or by other known methods or devices.
[0138] In a related approach (FIG. 55), another embodiment of a
threaded sensor assembly 252 can include a sharpened terminal end
254 as well as a superior 256 and inferior 258 portions that
collapse about opposite sides of target tissue or structure 259. A
sensing device 260 is positioned on the superior portion 256 and
the inferior end portion 258 includes a cap structure 261 defining
a releasable connection to a delivery catheter having a screw
device 262.
[0139] Significantly, the sensor assembly 252 can include a body
formed from silicone tubing for the purpose of providing an
atraumatic surface engaging the target structure. In one particular
aspect, the tubing could be configured to include a side or coaxial
lumen to be filled with a medium of air or liquid for inflation to
promote sealing at a puncture site.
[0140] Various other sensor assemblies and delivery catheters are
shown in FIGS. 56-65. As shown in FIGS. 56 and 57, a sensing device
270 can form a superior end of a delivery catheter 272. When placed
across target tissue or other structure 274, the delivery catheter
272 can be removed, leaving the sensing device implanted. The
sensing device 270 can have a pointed terminal end 275, a capsule
276 that retains a sensor and an inferior portion 277 that is
releasably connected to the delivery catheter 272 and which
traverses the target tissue. As seen in FIGS. 58 and 59, an
alternative embodiment of a sensing device 280 can have a sensor
attached to a pointed terminal end thereof and can lack any
substantial inferior portion extending inferior to target tissue
274. In each embodiment, the portion of the sensor assemblies
extend beyond the target tissue 274 to thereby provide a space
between the target tissue 274 and the sensor of the sensing
devices.
[0141] In yet another aspect, the sensing device can include clamps
284 (See FIGS. 60-62) which engage an inferior side of a target
tissue or other structure 274 upon placement of a sensor 286 beyond
the target tissue 274. An access tube 288 of any of the various
previously described devices can be employed to accomplish the
implantation of the sensor device adjacent the target tissue.
Another approach (See FIG. 63) involves equipping another
embodiment of a sensing device 290 with a helical coil 292 with a
sharp leading edge that facilitates driving the device across
target tissue. A sensor 294 is attached to a back end of the
helical coil 292 followed by a mesh pad 295 designed to fill the
opening created by the coil. The mesh pad 295 is contemplated to be
pre-treated where desired with a clotting agent to speed sealing
the opening.
[0142] Referring now to FIGS. 64 and 65, there is shown a sensor
delivery catheter 300 having a superior end portion 310 for
receiving a sensing device 302, a midsection 303 that accepts the
length of a loaded, straightened coil 304 and a pusher 305. The
pusher 305 is contemplated to facilitate advancing the sensing
device 302 beyond target tissue 306. Once beyond the target tissue,
the straightened coil 304 is designed to resume a helical
configuration to thereby route the sensor 302 a desired distance
beyond the target tissue. An inferior portion 307 of the coil 304
is permitted to extend through and reside on a near side of the
target tissue to thereby hold the sensing device 302 in place. As
with each of the previous embodiments, the catheter can be employed
to deliver a sensor beyond any structure including walls defining a
graft.
[0143] In certain circumstances, it may be advantageous to combine
aspects of a steering catheter with a sensor delivery system.
Various approaches are contemplated, particular embodiments of
which are shown in FIGS. 66-73. One embodiment of a steerable
sensor delivery system 310 (FIGS. 66 and 67) includes a steering
wire 312, a main catheter 313, an ejection system 314 and an outer
sheath assembly 315. The main catheter 313 further includes a
superior end portion configured to receive a sensor 316 and which
is equipped with a cut-out 317 through which the sensor 316 is
ejected from the main catheter 313.
[0144] When in an assembled form, the main catheter 313 houses the
steering wire 312 which is attached to a wall of the main catheter
at a point 318 inferior the cut-out 317. As with conventional
steering wires, a superior portion thereof 319 accomplishes the
steering function. The superior portion 319 can include any
structure which accomplishes the bending or curving of the catheter
313 such as a two wire system or side cut-outs or the like which
are brought together causing it to bend externally through the
manipulation of the steering wire 312. The outer sheath 315
surrounds the main catheter 313 and is retractable with respect
thereto. The main catheter 313 can further include a terminal end
cap 320 having a tapered or conical profile.
[0145] In use, the terminal end 320 and superior portion of the
steerable sensor delivery catheter 310 can be passed through a
vessel wall or other target tissue or structure 322. When so
positioned inferior end portions (not shown) of the steering wire
312 can be manipulated to cause lateral movement of the main
catheter 313. Through necessary positioning and/or rotation of the
main catheter 313, the sensor 316 is positioned adjacent tissue
intended for implantation.
[0146] Ejection of the sensor 316 from the main catheter 313 can be
accomplished in a number of ways. In one approach (FIGS. 68-70),
the sensor delivery system 310 is equipped with a release wire 324
and the main catheter 313 includes a pair of exit ports 325. The
ejection system 314 includes a sensor engaging platform 326
extending from which are a couple of rods 327. A spring 328 is
configured about each rod 327 and each rod further includes a
through hole 329. When in an assembled configuration, the ejection
system 214 is held in a retracted position by threading the release
wire 314 through the exit ports 325 of the main catheter 313 and
through the holes 329 of the rods 327 extending from the sensor
platform 326. The springs 328 are in turn held in a compressed
configuration and store the energy to eject the sensor 316 from the
main catheter 313.
[0147] Subsequent to passing the main catheter 313 through a target
tissue 322, the steering wire 312 is manipulated to cause the main
catheter 313 to be oriented such that the sensor 316 is placed
adjacent an implantation site. Thereafter, the release wire 324 is
withdrawn from engagement with the ejection system 314 thereby
allowing the spring 328 to force the sensor platform 326 to eject
the sensor 316 from the main catheter 313.
[0148] In an alternate approach (See FIG. 71), the ejection system
314 can comprise an inflatable balloon 330 attached to the end of
an inflation lumen 332. When advanced to target structure, the
balloon 330 is held in a deflated configuration. Once access to the
target is obtained, if necessary, the steering wire 312 is
manipulated to position a sensor 316 loaded in the main catheter
313 as desired. Next, the balloon 330 is inflated to cause the
ejection and implantation of the sensor at a target site.
[0149] In a further aspect (See FIGS. 72 and 73), a sensor delivery
system 340 for implanting a sensor assembly 342 having a nose cone
343 includes a handle assembly having an elongate barrel 344 with a
split diaphragm terminal end 345. The barrel 344 is intended to
extend from exterior a patient to an implantation site. The split
diaphragm provides an atraumatic surface for engaging the target
tissue or other structure as well as a working space through which
the nose cone 343 of the sensor 342 is intended to be ejected.
[0150] The handle assembly of the sensor delivery system 340
further includes a trigger 346 that is operationally connected to a
pusher assembly 347 that is intended to cause the sensor 342 to be
ejected through the split diaphragm 345. That is, pulling the
trigger 346 causes the pusher assembly 347 to advance and place the
sensor in a superior direction and ultimately be ejected from the
barrel 344. As the sensor 342 is so ejected, the nose cone 345 of
the sensor breaches the target structure 350. By employing one of
the previously described steering mechanisms, the sensor can be
caused to be placed adjacent and implanted at a target site.
[0151] One of several methods can be employed to cause the sensor
342 to be retained against target tissue. The sensor 342 can be
equipped with barbs or pins 352 (See FIG. 73) alone or can further
cooperate with self locking caps 354 (See FIG. 74) that engage the
barbs 352. The sensor assembly 342 can further include pliable
material 356 for cushioning the target tissue and to aid in the
healing and sealing process. Moreover, the caps can include one-way
spring clips and the barbs or pins 352 can be serrated or grooved
to aid in maintaining engagement between the component parts. It is
contemplated that the self-locking caps 354 can be delivered to the
target site via a separate catheter or the original delivery
catheter.
[0152] In yet another aspect, the target site 350 can first be
configured with a patch assembly 360 for the purpose of aiding in
reducing the likelihood of tearing at the target site. That is, a
patch assembly 360 includes a first patch 361 configured to be
placed on a near side of target tissue or wall 350 and a second
patch 362 for placement on the far side of the target tissue or
wall 350 can be utilized to prepare a sensor delivery site. The
patent assembly 360 further is contemplated to include a one way
gate 363 through which a sensor 342 can be placed and ultimately be
implanted on the far side of the tissue. Locking pins like those
previously described can be provided to hold the assembly
together.
[0153] Various approaches have been described herein to place
sensors on target tissue or grafts or other structure for the
purpose of monitoring desired parameters in an area of interest. It
is to be recognized that whereas the disclosed embodiments have
been described as having certain structure, the components can be
stored and incorporated into other embodiments as needed.
* * * * *