U.S. patent application number 11/244130 was filed with the patent office on 2006-10-26 for catheter system for implanting an intravascular medical device.
This patent application is currently assigned to Kenergy, Inc.. Invention is credited to Arthur J. Beutler, Cherik Bulkes, Stephen Denker.
Application Number | 20060241732 11/244130 |
Document ID | / |
Family ID | 36829783 |
Filed Date | 2006-10-26 |
United States Patent
Application |
20060241732 |
Kind Code |
A1 |
Denker; Stephen ; et
al. |
October 26, 2006 |
Catheter system for implanting an intravascular medical device
Abstract
A catheter system and method are employed to implant components
of a medical device inside an animal. The catheter system includes
a plurality of coaxial catheters and sheaths between which
electrically interconnected components of the medical device are
releasably held. A guide wire is inserted to a desired location
inside the animal and the plurality of catheters and sheaths is
slid as an assembly along the guide wire to that location. One of
the sheaths is moved with respect to the other catheters and
sheaths to release one of the components. The guide wire and the
remaining catheters and sheaths are repositioned to a second
location inside the animal and manipulated to release another
component. Additional components can be implanted by further
repositioning and manipulating steps. The catheter system is
removed from the animal leaving the components in place.
Inventors: |
Denker; Stephen; (Mequon,
WI) ; Bulkes; Cherik; (Sussex, WI) ; Beutler;
Arthur J.; (Greendale, WI) |
Correspondence
Address: |
QUARLES & BRADY LLP
411 E. WISCONSIN AVENUE
SUITE 2040
MILWAUKEE
WI
53202-4497
US
|
Assignee: |
Kenergy, Inc.
|
Family ID: |
36829783 |
Appl. No.: |
11/244130 |
Filed: |
October 5, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11112181 |
Apr 22, 2005 |
|
|
|
11244130 |
Oct 5, 2005 |
|
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Current U.S.
Class: |
607/116 |
Current CPC
Class: |
A61N 1/37205 20130101;
A61N 1/395 20130101; A61N 1/36114 20130101; A61N 1/3787 20130101;
A61N 1/37211 20130101 |
Class at
Publication: |
607/116 |
International
Class: |
A61N 1/05 20060101
A61N001/05 |
Claims
1. A catheter system for implanting a medical device in an animal,
wherein the medical device has a plurality of components for
implantation at different locations, said catheter system
comprising: a guide wire; an inner catheter with a guide wire lumen
within which the guide wire is slidably receivable; and a tubular
outer sheath through which the inner catheter extends, wherein a
first component and a second component of the medical device being
releasably located between the inner catheter and the outer sheath
with an electrically conductive wire connected to both the first
and second components; wherein the catheter system is manipulable
to independently release each of the first component and the second
component at different locations in the animal.
2. The catheter system as recited in claim 1 further comprising:
first cavity formed between the inner catheter and the outer sheath
within which a first component of the medical device is releasably
located; and a second cavity formed between the inner catheter and
the outer sheath within which a second component of the medical
device is releasably located, wherein the electrically conductive
wire extends between the first and second cavities; and a member
separating the first and second cavities.
3. The catheter system as recited in claim 1 wherein the tubular
outer sheath is slidable with respect to the inner catheter to
release the first component into the animal.
4. The catheter system as recited in claim 1 further comprising an
intermediate catheter extending within the tubular outer sheath and
having a lumen within which the inner catheter extends.
5. The catheter system as recited in claim 4 wherein the
intermediate catheter and the inner catheter are slidable with
respect to each other to release the second component into the
animal.
6. A catheter system for implanting a medical device in an animal,
wherein the medical device has a plurality of components that are
electrically interconnected, said catheter system comprising: a
first guide wire; a first catheter with a first lumen extending
along a longitudinal axis and within which the first guide wire is
slidably receivable; a second catheter with a second lumen in which
the first catheter is slidably received, wherein a first cavity is
defined between the first and second catheters; a first component
of the medical device releasably located in the first cavity; a
tubular first outer sheath through which the second catheter
slidably extends, wherein a second cavity is defined between the
second catheter and the first outer sheath; and a second component
of the medical device releasably located in the second cavity.
7. The catheter system as recited in claim 6 wherein the tubular
first outer sheath is slidable with respect to the second catheter
to release the second component into the animal.
8. The catheter system as recited in claim 6 wherein the second
catheter is slidable with respect to the first catheter to release
the first component into the animal.
9. The catheter system as recited in claim 6 further comprising a
first inner sheath between the first and second catheters with the
first component located between the first inner sheath and the
first catheter.
10. The catheter system as recited in claim 6 wherein the first
component is one of a stimulation circuit, an antenna, and an
electrode, and the second component is another one of a stimulation
circuit, an antenna, and an electrode.
11. The catheter system as recited in claim 6 wherein at least one
of the first component and the second component comprises an
expandable body that is held in a collapsed state in the catheter
system and which expands upon being released from the catheter
system.
12. The catheter system as recited in claim 6 wherein the first
component and the second component are located in tandem along the
longitudinal axis.
13. The catheter system as recited in claim 6 further comprising: a
third catheter within the first outer sheath and having a third
lumen through which the second catheter is slidably received,
wherein the second cavity is formed between the second and third
catheters and a third cavity is formed between the third catheter
and the first outer sheath; and a third component of the medical
device releasably located in the third cavity.
14. The catheter system as recited in claim 13 further comprising:
a first inner sheath extending between the first and second
catheters with the first component located between the first inner
sheath and the first catheter; and a second inner sheath extending
between the second and third catheters with the second component
located between the second inner sheath and the second
catheter.
15. The catheter system as recited in claim 6 further comprising; a
second guide wire; a third catheter with a third lumen within which
the second guide wire is slidably receivable; a second outer sheath
through which the third catheter slidably extends, wherein a third
cavity is defined between the third catheter and the second outer
sheath; and a third component of the medical device releasably
located in the third cavity and electrically connected by a wire to
one of the first and second components.
16. The catheter system as recited in claim 6 further comprising; a
second guide wire; a third catheter with a third lumen in which the
second guide wire is slidably receivable; a fourth catheter with a
fourth lumen in which the third catheter is slidably received,
wherein a third cavity is defined between the third and fourth
catheters; a third component of the medical device releasably
located in the third cavity; a tubular second outer sheath through
which the fourth catheter slidably extends, wherein a fourth cavity
is defined between the fourth catheter and the second outer sheath;
and a fourth component of the medical device releasably located in
the second cavity; wherein at least one of the third component and
the fourth component is electrically connected by a wire to one of
the first component and the second component.
17. The catheter system as recited in claim 16 further comprising
an inner sheath extending between the third and fourth catheters
with the third component located between the inner sheath and the
third catheter.
18. A method of implanting a medical device in an animal, wherein
the medical device has a plurality of components, said method
comprising: inserting a first guide wire to a first location inside
the animal; inserting a first catheter assembly releasably
containing a first component and a second component of the medical
device over the first guide wire until the first catheter assembly
reaches the first location, wherein the first component and the
second component are electrically connected; releasing one of the
first component and the second component at the first location
inside the animal; repositioning the first catheter assembly to a
second location inside the animal; and releasing another one of the
first component and the second component at the second location
inside the animal.
19. The method as recited in claim 18 wherein inserting a first
catheter assembly comprises employs a first catheter assembly that
comprises a first catheter with a first lumen within which the
first guide wire is received, and a tubular first outer sheath
through which the first catheter extends, a first cavity defined
between the first catheter and the first outer sheath and
releasably containing a first component of the medical device, and
a second cavity defined between the first catheter and the first
outer sheath and releasably containing a second component of the
medical device.
20. The method as recited in claim 19 wherein repositioning the
first catheter assembly comprises relocating the first guide wire
adjacent the second location.
21. The method recited in claim 19 further comprising removing the
first catheter assembly from the animal leaving the first and
second components inside the animal.
22. The method as recited in claim 19 wherein the first catheter
assembly further comprises a second catheter within the first outer
sheath and having a second lumen within which the first catheter is
slidably received, wherein the first cavity is defined between the
first and second catheters and the second cavity is defined between
the second catheter and the first outer sheath.
23. The method as recited in claim 22 wherein repositioning the
first catheter assembly comprises relocating the first guide wire
adjacent the second location.
24. The method as recited in claim 23 wherein repositioning the
first catheter assembly further comprises sliding at least one of
the first and second catheters along the first guide wire to the
second location.
25. The method as recited in claim 22 wherein releasing one of the
first component and the second component comprises sliding the
first outer sheath and the second catheter with respect to each
other.
26. The method as recited in claim 22 wherein releasing another one
of the first component and the second component comprises sliding
the first catheter and the second catheter with respect to each
other.
27. The method as recited in claim 22 wherein the first catheter
assembly further comprises an inner sheath extending between the
first and second catheters; and wherein releasing another one of
the first component and the second component comprises sliding the
inner sheath and the first catheter with respect to each other.
28. The method as recited in claim 22 further comprising: inserting
a second guide wire to a third location inside the animal;
inserting a second catheter assembly over the second guide wire
until the second catheter assembly reaches the third location,
wherein the second catheter assembly comprises a third catheter
with a third lumen in which the second guide wire is slidably
received, and a tubular second outer sheath through which the third
catheter slidably extends, wherein a third cavity is defined
between the third catheter and the second outer sheath and
releasably contains a third component that is electrically
connected by a wire to one of the first and second components; and
releasing the third component inside the animal.
29. The method as recited in claim 28 wherein inserting a first
catheter assembly and inserting a second catheter assembly are
performed in unison.
30. The method as recited in claim 28 wherein releasing the third
component comprises sliding the second outer sheath and the third
catheter with respect to each other.
31. The method as recited in claim 28 further comprising removing
the second catheter assembly from the animal while leaving the
third component inside the animal.
32. The method as recited in claim 22 further comprising: inserting
a second guide wire to a third location inside the animal;
inserting a second catheter assembly over the second guide wire
until the second catheter assembly reaches the third location,
wherein the second catheter assembly comprises a third catheter
with a third lumen in which the second guide wire is slidably
received, a fourth catheter with a fourth lumen within which the
third catheter is slidably received, a third cavity defined between
the third and fourth catheters and releasably containing a third
component of the medical device, a tubular second outer sheath
through which the fourth catheter slidably extends, and a fourth
cavity defined between the fourth catheter and the second outer
sheath and releasably containing a fourth component of the medical
device, wherein at least one of the third and fourth components is
electrically connected by a wire to one of the first and second
components; releasing one of the third component and the fourth
component inside the animal; repositioning the second catheter
assembly to a fourth location in the animal; and releasing another
one of the third component and the fourth component inside the
animal.
33. The method as recited in claim 32 wherein inserting a first
catheter assembly and inserting a second catheter assembly are
performed in unison.
34. The method as recited in claim 32 wherein repositioning the
second catheter assembly comprises: moving the second guide wire
adjacent the fourth location; and sliding at least one of the third
and fourth catheters along the second guide wire to the fourth
location.
35. The method as recited in claim 32 wherein releasing one of the
third component and the fourth component comprises sliding the
second outer sheath and the fourth catheter with respect to each
other.
36. The method as recited in claim 32 wherein releasing another one
of the third component and the fourth component comprises sliding
the third catheter and the fourth catheter with respect to each
other.
37. The method as recited in claim 32 wherein the second catheter
assembly further comprises an inner sheath extending between the
third and fourth catheters; and wherein releasing another one of
the third component and the fourth component comprises sliding the
inner sheath and the third catheter with respect to each other.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation in part of U.S. patent application
Ser. No. 11/112,181 filed on Apr. 22, 2005.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to medical devices that are
implanted into the vasculature of an animal, and more particularly
to the apparatus for performing the implantation.
[0005] 2. Description of the Related Art
[0006] A remedy for people with slowed or disrupted natural heart
activity is to implant a cardiac pacing device which is a small
electronic apparatus that stimulates the heart to beat at regular
rates.
[0007] Typically the pacing device is implanted in the patient's
chest and has sensor electrodes that detect electrical impulses
associated with in the heart contractions. These sensed impulses
are analyzed to determine when abnormal cardiac activity occurs, in
which event a pulse generator is triggered to produce electrical
pulses. Wires carry these pulses to electrodes placed adjacent
specific cardiac muscles, which when electrically stimulated
contract the heart chambers. It is important that the electrodes be
properly located to produce contraction of the heart chambers.
[0008] Modem cardiac pacing devices vary the stimulation to adapt
the heart rate to the patient's level of activity, thereby
mimicking the heart's natural activity. The pulse generator
modifies that rate by tracking the activity of the sinus node of
the heart or by responding to other sensor signals that indicate
body motion or respiration rate.
[0009] U.S. Pat. No. 6,445,953 describes a cardiac pacemaker that
has a pacing device, which can be located outside the patient, to
detect abnormal electrical cardiac activity. In that event, the
pacing device emits a radio frequency signal, that is received by a
stimulator implanted in a vein or artery of the patient's heart.
Specifically, the radio frequency signal induces a voltage pulse in
an antenna on the stimulator and that pulse is applied across a
pair of electrodes, thereby stimulating adjacent muscles and
contracting the heart.
[0010] The stimulator in that wireless system is powered by the
energy of the received signal thus requiring that the pacing device
transmit a relatively strong radio frequency signal in order to
provide adequate energy to the stimulator implanted deep in the
patient's chest. It is desirable to place the stimulator, or at
least the antenna for the stimulator, in a blood vessel located
closer to the skin of the patient with electrodes implanted in one
or more cardiac blood vessels and connected to the stimulator by
wires extending through the electronic circuit circulatory system.
This would enable more of the energy from the frequency signal to
reach the stimulator, however, the blood vessels close to the skin
are not sufficiently large to accommodate the size of the
stimulator.
[0011] The antenna, usually in the form of a coil, must possess
several characteristics in order to function within the blood
vessel. The coil must retain its shape in order to remain tuned to
the particular radio frequency being used. The conductors of the
antenna have to be insulated so that the blood and other substances
flowing through the vascular system do not provide a short circuit
or otherwise detune the antenna. In addition the antenna must be
biologically compatible with the blood vessel walls and with the
blood.
[0012] Therefore, it is desirable to provide an apparatus for
positioning each of the components of the medical device in the
patient.
SUMMARY OF THE INVENTION
[0013] A catheter system is provided to implant a medical device in
an animal, wherein the medical device has a plurality of components
that are to be placed at different locations. The system is
particular adapted to implant a medical device in which the
components are electrically interconnected by wires.
[0014] The catheter system comprises a guide wire, a first catheter
with a guide wire lumen for slidably receiving the guide wire, and
a tubular outer sheath through which the first catheter extends. A
first cavity is formed between the first catheter and the outer
sheath within which a first component of the medical device is
releasably located. A second cavity also is formed between the
first catheter and the outer sheath within which a second component
of the medical device is releasably located.
[0015] In a preferred embodiment, the catheter system further
includes a second catheter with a lumen within which the first
catheter is slidably received. Thus, the first and second catheters
are both within the outer sheath. The first cavity is located
between the first and second catheters and the second cavity is
located between the second catheter and the outer sheath. As an
option, an inner sheath may be provided between the first and
second catheters, with the first cavity between the first catheter
and the inner sheath. More catheters and sheaths may be added
coaxially on the catheter system to deliver additional components
into the animal.
[0016] The catheter system is manipulatable to independently
release each of the first and second components at different
locations in the animal. Initially the guide wire is inserted into
the animal to a first location. Then, the assembly of catheters is
slid over the guide wire until reaching the first location. The
outer sheath is moved over the second catheter to expose the second
component, that is deposited at the first location.
[0017] If a desired second location for implantation of the second
first component is along the existing route of the guide wire
through the animal, the first and second catheters are slid along
the guide wire to place the first component at the second location.
Otherwise, the guide wire can be repositioned to the second
location before the first and second catheters are slid into place.
Thereafter, the first and second catheters are moved with respect
to each other to expose the first component, which is deposited at
the second location.
[0018] A second embodiment of a catheter system having two guide
wires and two catheter assemblies, one for each guide wire, also is
described. The two catheter assemblies cooperate to implant a
greater plurality of components, that are electrically
interconnected by wires.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] FIG. 1 is a representation of a cardiac pacing system
attached to a medical patient;
[0020] FIG. 2 is an isometric, cut-away view of a patient's blood
vessels in which a receiver antenna, a stimulator and an electrode
of an intravascular medical device have been implanted at different
locations;
[0021] FIG. 3 is a longitudinal cross sectional view through a
distal end of a catheter system for implanting the components of
the intravascular medical device;
[0022] FIG. 4 is a transverse cross sectional view through a
catheter system along line 4-4 of FIG. 3;
[0023] FIG. 5 is a transverse cross sectional view through a
catheter system along line 5-5 of FIG. 3;
[0024] FIG. 6 is a transverse cross sectional view through a
catheter system along line 6-6 of FIG. 3;
[0025] FIGS. 7-14 depict a sequence of steps by which the
components of the intravascular medical device are implanted in the
patient; and
[0026] FIGS. 15-25 illustrate an alternative sequence of steps by
which the medical device components are implanted in a patient's
vascular system.
DETAILED DESCRIPTION OF THE INVENTION
[0027] Although the present invention is being described in the
context of implanting components of a cardiac pacing system, it can
be used to implant other types of medical devices into a patient's
body. Furthermore, the present apparatus and method are not limited
to implanting items in an animal's vascular system, but can be
employed to implant elements elsewhere in the animal.
[0028] Initially referring to FIG. 1, a cardiac pacing system 10
for electrically stimulating a heart 12 to contract comprises an
external power source 14 and a medical device 15 implanted in the
circulatory system of a human medical patient. The medical device
15 receives a radio frequency (RF) signal from the power source 14
worn outside the patient and the implanted electrical circuitry is
electrically powered from the energy of that signal. At appropriate
times, the medical device 15 delivers an electrical stimulation
pulse into the surrounding tissue of the patient.
[0029] The power source 14 may be the same type as described in
U.S. Pat. Nos. 6,445,953 and 6,907,285 and includes a radio
frequency transmitter that is powered by a battery. The transmitter
periodically emits a signal at a predefined radio frequency that is
applied to a transmitter antenna in the form of a coil of wire
within a band 22 that is placed around the patient's upper arm 23.
In a basic version of the cardiac pacing system 10, the radio
frequency signal merely conveys energy for powering the medical
device 15 implanted in the patient. In other systems, the
transmitter modulates the radio frequency signal with commands
received from optional circuits that configure or control the
operation of the medical device 15.
[0030] Referring to FIGS. 1 and 2, the exemplary implanted medical
device 15 includes an intravascular stimulator 16 located a vein or
artery 18 in close proximity to the heart. Because of its
electrical circuitry, the stimulator 16 is relatively large
requiring a blood vessel that is larger than the arm vein, e.g. the
basilic vein, which is approximately five millimeters in diameter.
Therefore, the stimulator 16 may be implanted in the superior or
inferior vena cava. Electrical wires lead from the stimulator 16
through the cardiac vascular system to one or more locations in
smaller blood vessels 19, e.g. the coronary sinus vein, at which
stimulation of the heart is desired. At such locations, the
electrical wire 25 are connected to a remote electrode 21 secured
to the blood vessel wall.
[0031] Because the stimulator 16 of the medical device 15 is near
the heart and relatively deep in the chest of the human medical
patient, a receiver antenna 24 for the RF signal is implanted in a
vein or artery 26 of the patient's upper right arm 23 at a location
surrounded by the transmitter antenna within the arm band 22. That
arm vein or artery 26 is significantly closer to the skin and thus
receiver antenna 24 picks up a greater amount of the energy of the
radio frequency signal emitted by the power source 14, than if the
receiver antenna was located on the stimulator 16. Alternatively,
another limb, neck or other area of the body with an adequately
sized blood vessel close to the skin surface of the patient can be
used. The receiver antenna 24 is connected to the stimulator 16 by
a micro-coaxial cable 34.
[0032] As illustrated in FIG. 2, the intravascular stimulator 16
has a body 30 constructed similar to well-known expandable vascular
stents. The stimulator body 30 comprises a plurality of wires
formed to have a memory defining a tubular shape or envelope. Those
wires may be heat-treated platinum, Nitinol, a Nitinol alloy wire,
stainless steel, plastic wires or other materials. Plastic or
substantially nonmetallic wires may be loaded with a radiopaque
substance which provide visibility with conventional fluoroscopy.
The stimulator body 30 has a memory so that it normally assumes an
expanded configuration when unconfined, but is capable of assuming
a collapsed configuration when disposed and confined within a
catheter assembly, as will be described. In that collapsed state,
the tubular body 30 has a relatively small diameter enabling it to
pass freely through the vasculature of a patient. After being
properly positioned in the desired blood vessel, the body 30 is
released from the catheter and expands to engage the blood vessel
wall. The stimulator body 30 and other components of the medical
device 15 are implanted in the patient's circulatory system using a
novel technique that employs a unique catheter system described
hereinafter.
[0033] The body 30 has a stimulation circuit 32 mounted thereon
and, depending upon its proximity to the heart 12, may hold a first
electrode 20 in the form of a ring that encircles the body.
Alternatively, when the stimulator 16 is relatively far from the
heart 12, the first electrode 20 can be remotely located in a small
cardiac blood vessel much the same as a second electrode 21. The
stimulation circuit 32, which may be the same type as described in
the aforementioned U.S. patents, includes a power supply to which
the micro-coaxial cable 34 from the receiver antenna 24 is
connected. The power supply utilizes electricity from that antenna
to charge a storage capacitor that provides electrical power to the
stimulation circuit. A conventional control circuit within the
stimulation circuit 32 detects the electrical activity of the heart
and determines when electrical pulses need to be applied so that
the heart 12 contracts at the proper rate. When stimulation is
desired, the stimulation circuit 32 applies electrical voltage from
its internal storage capacitor across the electrodes 20 and 21. The
second electrode 21 and the first electrode when located remotely
from the stimulator 16, can be mounted on a collapsible body of the
same type as the stimulator body 30.
[0034] With reference to FIG. 3, the components of the medical
device 15 are inserted into the patient utilizing a catheter system
50 which is a meter or more long as is necessary to extend from an
incision in the patient through the vascular system to the various
locations where the components of the medical device 15 are to be
implanted. The catheter system 50 has a proximal end that remains
outside the patient to which the physician has access to manipulate
the elements of the catheter system, and has a distal end that is
inserted into the patient and which contains the medical device
components.
[0035] The distal end section of the catheter system 50 is
illustrated in FIG. 3 to which continuing reference is made. The
catheter system comprises a conventional guide wire 52 over which
an assembly 51 of several catheters and sheaths are coaxially
inserted. Those catheters and sheaths are made of a flexible
biologically compatible material commonly used for medical
catheters. A first, or inner, catheter 54 has a tubular
construction with a lumen 55 through which the guide wire 52
extends, see also the cross-section through this region of the
catheter system 50 in FIG. 4. A first component, such as the second
electrode 21, of the medical device is positioned around the end of
the first catheter 54 with a first inner sheath 56 around the first
component to maintain it in a collapsed state. A first cavity 57 is
formed between the first catheter 54 and the first inner sheath 56
within which the first component is located. The first inner sheath
56 extends longitudinally to the proximal end of the first catheter
54 which is outside the patient. Both the first catheter 54 and the
first inner sheath 56 have a distal end that is spaced from the
distal end 53 of catheter assembly 51.
[0036] A second, or intermediate, catheter 58 extends
longitudinally over the first inner sheath 56 so that the inner
components of the catheter system 50 described thus far are located
within a lumen 60 of the second catheter 58, see also the
cross-section through this region in FIG. 5. The end of the second
catheter projects beyond the end of the first catheter, but falls
short of the distal end 53 of the catheter assembly 51. The antenna
40, which also is referred to herein as a second component of the
medical device 15, is placed around the end section of the second
catheter 58 and is held in an elongated, reduced diameter state by
a second inner sheath 62 that extends around the antenna 40 and
along the second catheter 58 to the proximal end of the catheter
system 50. A second cavity 63 is defined between the second
catheter 58 and the second inner sheath 62 within which the second
medical device component is located.
[0037] With reference to FIGS. 3 and 6, a third catheter 64 is
located around and extends along the outside of the second inner
sheath 62 and projects to substantially the distal end 53 of the
catheter assembly 51. A third component, in this case the
stimulator 16, is located around the third catheter 64 and is held
in its collapsed state by a third, or outer, sheath 66 that forms
the outermost element of the catheter system 50 extending around
all of the other elements. A third cavity 65 is located between the
third catheter 64 and the third sheath 66 within which the
stimulator 16 is located. The electrical wire 25 extends from the
stimulator 16 through the catheter system 50 to the first
component, electrode 21, and the micro-coaxial cable 34 extends
from the stimulator 16 to the second component 40. More coaxially
arranged catheters and sheaths can be provided to deliver
additional components of a medical device.
[0038] The medical device 15 is implanted in the vascular system of
the patient by first inserting the guide wire 52 as depicted in
FIG. 7. An incision is made into large blood vessel in the
patient's thigh, for example, using conventional surgical
procedures for inserting catheters. The guide wire 52 is then
threaded through the vasculature until its distal end reaches the
location at which the stimulator 16 is to be implanted. Next, the
catheter assembly 51 is inserted over the proximal end of the guide
wire 52 and pushed there along to the location selected for the
stimulator implantation, as shown in FIG. 8. With the stimulator 16
properly positioned within the blood vessel 18, the outer, or third
sheath 66 is pulled out of the patient while maintaining the
remainder of the catheter system 50 in place. Once the third sheath
66 clears the stimulator 16, the stimulator's body 30 expands
diametrically against the wall of the blood vessel 18 thereby
securing the stimulator 16 in place, as illustrated in FIG. 9. This
diametric expansion of the stimulator body 30 causes a longitudinal
contraction as evident from a comparison of the length of the
stimulator 16 in FIGS. 8 and 9. It should be noted that before the
third sheath 66 fully exposes the stimulator body 30, that sheath
can be pushed back into the patient over the third catheter 64 and
the exposed portion of the stimulator 16. This action re-collapses
the stimulator body 30 so that it may be repositioned within the
blood vessel 18.
[0039] With reference to FIG. 10, after implanting the stimulator
16, the guide wire 52 is advanced through the vascular system until
it reaching a point at which the antenna 40 is desired to be placed
in blood vessel 26. Thereafter, the remainder of the catheter
assembly 51 is advanced along the guide wire 52 until the distal
end 53 reaches the desired location (as seen as FIG. 3). As this
advancement occurs, the micro-coaxial cable 34 connecting the
antenna 40 to the stimulator 16 is unfurled from catheter assembly.
Next, the physician withdraws the second inner sheath 62 from the
patient. When the second inner sheath 62 has been withdrawn
sufficiently to expose the antenna 40, that component contracts
longitudinally and expands diametrically against the inner surface
of the blood vessel 26. That action secures the antenna 40 in
place, as shown in FIG. 11. Before the antenna 40 has been fully
exposed, the second inner sheath 62 may be pushed back into the
patient to re-collapse the partially expanded antenna, if
necessary.
[0040] With the antenna 40 secured in place, the physician extracts
the remainder of the catheter system 50, including the guide wire
52 from the blood vessel 26 to a junction where the assembly can be
directed into the other blood vessel 19 for implantation of the
second electrode 21. From that withdrawn position, the guide wire
52 alone is advanced through the vascular system until its distal
end reaches the location within blood vessel 19 at which the
electrode is to be implanted. Then, the remainder of the catheter
assembly 51 is advanced along the guide wire 52 until its distal
end 53 reaches the distal end of the guide wire, as depicted in
FIG. 12. At this point, the first, or inner, catheter 54 and its
surrounding sheath 56 are located at the distal end of the guide
wire along with the second electrode 21. With that electrode
properly positioned within the blood vessel 19, the first sheath 56
is withdrawn from the patient along the first catheter 54. Upon
being exposed, the second electrode 21 expands to engage the wall
of the blood vessel 19, thereby being secured in place as
illustrated in FIG. 13. Other techniques for securing the electrode
and the other components in the blood vessel wall may be employed.
Then, the first catheter 54 and guide wire 52 are withdrawn from
the vascular system of the patient leaving the components of the
medical device 15 in place, as shown in FIG. 14.
[0041] The first catheter system 50 employs a single catheter
assembly 51 that comprises coaxially located catheters and sheaths
to carry the components of the medical device 15. FIGS. 15-22
illustrate a second catheter system 70 having first and second
catheter assemblies 71 and 72, which are inserted through the
vascular system of the patient. These catheter assemblies 71 and 72
are structurally each similar to the catheter assembly 51
previously described. The first catheter assembly 71 is used to
deliver the stimulator 16 and the antenna 40, and the second
catheter assembly 72 delivers a pair of electrodes 87 and 90 to
different locations in the patient's vasculature. The implantation
procedure commences by inserting a first guide wire 74 into the
patient and threading it through the vascular system until reaching
a position 75 in blood vessel 26 at which the antenna 40 is to be
located as shown in FIG. 15. A second guide wire 76 also is
inserted through the vascular system to a location 77 in blood
vessel 19 for one of the electrodes. Then the first catheter
assembly 71 is placed over the first guide wire 74 and the second
catheter assembly 72 is placed over the second guide wire 76. The
two catheter assemblies are slid in unison over their respective
guide wires until the first catheter assembly 71 reaches the
location 79 in blood vessel 18 for the stimulator 16 as illustrated
in FIG. 16. The two catheter assemblies 71 and 72 have to be
inserted simultaneously into the patient because the components
carried by them are connected by relatively short electrical wires.
Alternatively those interconnecting wires may be long enough to
extend outside the patient while only some of the components have
been implanted. This eliminates the need to simultaneously insert
both catheter assemblies 71 and 72 and also permits testing of each
component upon being finally positioned in the vascular system. For
example, the antenna 40 can be tested for adequate signal reception
before implanting the stimulator 16.
[0042] The first catheter assembly 71 has a first catheter 78 with
a second catheter 80 extending coaxially there around.
Specifically, the first catheter 78 has a lumen through which the
first guide wire 74 passes and the second catheter 80 has another
lumen within which the first catheter is received. A first cavity
is formed between those catheters within which the antenna 40 is
located. In the second catheter system 70, there is no inner sheath
between the antenna and the second catheter 80, however such a
sheath could be provided as in the previously described catheter
system 50. A first outer sheath 82 extends longitudinally along and
around the second catheter 80 forming a second cavity there between
within which the stimulator 16 is located adjacent the distal end
of the first catheter assembly 71.
[0043] The second catheter assembly 72 has a third catheter 84
immediately surrounding the second guide wire 76. A fourth catheter
86 extends coaxially around and along the third catheter 84 forming
a cavity there between within which a first electrode 87 is
located. In particular, the third catheter 84 has a lumen through
which the second guide wire 76 passes and the fourth catheter 86
has another lumen within which the third catheter is received. A
second outer sheath 88 extends coaxially around and along the
fourth catheter 86 forming a cavity there between within which a
second electrode 90 is held.
[0044] With reference to FIG. 17, while the first catheter assembly
71 is held in place, the second catheter assembly 72 is advanced
along the second guide wire 76 past the end of the first catheter
assembly 71 and into the blood vessel 19. As this advancement
occurs, the electrical wires connecting the first and second
electrodes 87 and 90 to the stimulator 16 are pulled along and
unfurled from the distal end of the second catheter assembly 72.
The second catheter assembly 72 continues slide over the second
guide wire 76 until reaching the location desired for implantation
of the second electrode 90. Then the second outer sheath 88 is
withdrawn from the patient by sliding it along the remaining
components of the second catheter assembly 72. That action exposes
the second electrode 90 which thereby expands diametrically to
become imbedded in the inner wall of the blood vessel 19, as shown
in FIG. 18. Other techniques for securing the electrode in the
blood vessel wall may be employed.
[0045] Then the third and fourth catheters 84 and 86 are withdrawn
partially from the patient carrying the first electrode 87 through
the blood vessel 19 until it is located at the desired place for
implantation, as depicted in FIG. 19. If the desired location for
the first electrode 87 is not along the existing route of the
second guide wire 76, that guide wire may also be partially
extracted from the patient and reinserted through a different route
to the desired implantation point. In that latter case, the two
catheters 84 and 86 then are slid along the second guide wire 76
until the first electrode 87 reaches that desired point of
implantation. When the first electrode is properly positioned, the
third catheter 84 is withdrawn from the patient so its distal end
slides over the first electrode 87. Upon being fully exposed, the
first electrode 87 expands diametrically thereby engaging the walls
of the blood vessel 19 becoming secured in place as illustrated in
FIG. 20. Here too, other techniques may be used to secure this
electrode in the blood vessel wall. Thereafter, the third catheter
84 and the second guide wire 76 are withdrawn from the patient
leaving the two electrodes 87 and 90 in place, as shown in FIG.
21.
[0046] Then with the first catheter assembly 71 still positioned at
the location desired for the stimulator 16, the first outer sheath
82 of the first catheter assembly 71 is withdrawn from the patient
to release the stimulator. When the body 30 of the stimulator is
fully exposed, it expands diametrically against the inner wall of
the blood vessel 18 to secure the stimulator 16 in place, as
depicted in FIG. 22. Next, the first and second catheters 78 and 80
are advanced along the first guide wire 74, through the now
expanded stimulator body 30, until the collapsed antenna 40 carried
by those catheters is located within the blood vessel 26 at the
desired position for implantation shown in FIG. 23. At this time,
the second catheter 80 is pulled at least partially from of the
patient to expose the antenna 40 thereby allowing the antenna coil
to expand against the inner wall of the blood vessel 26 as
exemplified in FIG. 24. Then, the first catheter 78 and the first
guide wire 74 are removed from the patient, either separately or in
unison. This leaves the medical device 15, comprising the
stimulator 16, antenna 40 and the first and second electrodes 87
and 90, implanted in the patient's vasculature as shown in FIG.
25.
[0047] The foregoing description was primarily directed to
preferred embodiments of the invention. Even though some attention
was given to various alternatives within the scope of the
invention, it is anticipated that one skilled in the art will
likely realize additional alternatives that are now apparent from
disclosure of embodiments of the invention. For example, different
quantities of components for the medical device can be implanted by
modifying the catheter assembly with more catheters and sheaths,
and the position of the components on the catheter assembly can be
changed to enable a different order of implantation. Accordingly,
the scope of the invention should be determined from the following
claims and not limited by the above disclosure.
* * * * *