U.S. patent application number 11/144447 was filed with the patent office on 2006-12-07 for coronary sinus lead for pacing the left atrium.
Invention is credited to Seth Worley.
Application Number | 20060276868 11/144447 |
Document ID | / |
Family ID | 37495158 |
Filed Date | 2006-12-07 |
United States Patent
Application |
20060276868 |
Kind Code |
A1 |
Worley; Seth |
December 7, 2006 |
Coronary sinus lead for pacing the left atrium
Abstract
A method of inserting a pacing lead having a preformed shape
into a coronary sinus to pace the left atrium includes providing a
lead having an elongated body and proximal and tip sections. The
sections are configured such that a first angle less than 90
degrees is defined between the lead body and proximal section and a
second angle is defined between the tip and proximal sections. The
method further comprises advancing the pacing wire towards the
opening of the coronary sinus and advancing the wire into the
coronary sinus, such that the first angle is compressed by the
coronary sinus opening and a tip electrode included on the tip
section contacts the wall of the coronary sinus near the left
atrium operably extending the second angle to assure constant
contact between the wall of the coronary sinus and the tip
electrode.
Inventors: |
Worley; Seth; (Lancaster,
PA) |
Correspondence
Address: |
PATTERSON, THUENTE, SKAAR & CHRISTENSEN, P.A.
4800 IDS CENTER
80 SOUTH 8TH STREET
MINNEAPOLIS
MN
55402-2100
US
|
Family ID: |
37495158 |
Appl. No.: |
11/144447 |
Filed: |
June 3, 2005 |
Current U.S.
Class: |
607/125 |
Current CPC
Class: |
A61N 1/057 20130101;
A61N 2001/0585 20130101; A61N 1/056 20130101 |
Class at
Publication: |
607/125 |
International
Class: |
A61N 1/05 20060101
A61N001/05 |
Claims
1. A pacing lead configured for implantation in a coronary sinus
having an opening and a wall defining an interior, the pacing lead
comprising: an elongated lead body having a first bend defined
thereon; a proximal section having a second bend defined thereon,
the proximal section extending from the first bend and defined
between the first and second bends, such that a first angle less
than 90 degrees is defined between the lead body and proximal
section; a tip section having a tip electrode disposed thereon, the
tip section extending from the second bend, such that a second
angle is defined between the tip and proximal sections, wherein the
pacing lead is configured such that when at least a portion of the
first bend is inserted into the opening of the coronary sinus, the
first angle is operably compressed by the coronary sinus opening
and the tip electrode contacts the wall of the coronary sinus
thereby operably extending the second angle.
2. The lead of claim 1, further comprising at least one secondary
electrode disposed on at least a portion of the lead.
3. The lead of claim 2, wherein the secondary electrode is disposed
on the proximal section.
4. The lead of claim 2, wherein the secondary electrode is disposed
on the tip section.
5. The lead of claim 1, wherein the first angle defined between the
lead body and proximal section is less than 45 degrees.
6. The lead of claim 1, wherein the second angle defined between
the tip and proximal sections is between 90 and 150 degrees.
7. The lead of claim 1, further comprising a stylet disposed
therein for selectively maintaining the stiffness of the lead as
the lead is inserted into the opening of the coronary sinus.
8. The lead of claim 1, further comprising a catheter and a
guidewire operably coupled to the catheter for guiding the lead
towards the opening of the coronary sinus.
9. The lead of claim 1, wherein the lead comprises a lead width,
the lead width being between 4 and 6 French.
10. A method of inserting a pacing lead having a preformed shape
into a coronary sinus to pace a left atrium, the coronary sinus
having an opening and a wall defining an interior, the method
comprising: providing a pacing lead comprising an elongated lead
body having a first bend defined thereon, a proximal section having
a second bend defined thereon, the proximal section extending from
the first bend and defined between the first and second bends, such
that a first angle less than 90 degrees is defined between the lead
body and proximal section, and a tip section having a tip electrode
disposed thereon, the tip section extending from the second bend,
such that a second angle is defined between the tip and proximal
sections; advancing the pacing wire towards the coronary sinus
opening; and advancing the first curve into the coronary sinus,
such that the first angle is operably compressed by the coronary
sinus opening and the tip electrode contacts the wall of the
coronary sinus proximate the left atrium thereby operably extending
the second angle.
11. The method of claim 10, further comprising: defining the first
angle between the lead body and proximal section to be less than 45
degrees; and advancing the first curve into the coronary sinus,
such that the first angle is operably compressed to less than 45
degrees by the wall of the coronary sinus.
12. The method of claim 10, further comprising: defining the second
angle defined between the tip and proximal sections to be between
90 and 150 degrees; and advancing the first curve into the coronary
sinus, such that the second angle is operably extended to greater
than 120 degrees by the wall of the coronary sinus.
13. The method of claim 10, further comprising advancing the first
curve into the coronary sinus, such that the tip electrode is in
substantially constant contact with the wall of the coronary sinus
proximate the left atrium.
14. The method of claim 10, further comprising: providing at least
one secondary electrode disposed on a portion of the pacing lead;
advancing the first curve into the coronary sinus, such that the
secondary electrode is in substantially constant contact with at
least a portion of the wall of the coronary sinus.
15. The method of claim 10, further comprising: providing a guide
catheter having a guide wire operably coupled thereto for guiding
the pacing wire towards the coronary sinus opening; anchoring the
guide wire into at least a portion of the coronary sinus; providing
a stylet and inserting the stylet into the pacing wire having the
preformed shape until the pacing wire comprises a substantially
linear shape; inserting the pacing wire having the substantially
linear shape into the guide catheter; advancing the guide catheter
and pacing wire to a position proximate the opening of the coronary
sinus; and withdrawing the stylet out of the pacing wire to a
position proximate the first bend; advancing the pacing wire out of
the sheath towards the opening of the coronary sinus, such that the
pacing lead comprises the preformed shape prior to advancing the
first curve into the coronary sinus.
16. A pacing lead configured for implantation in a coronary sinus
having an opening and a wall defining an interior, the pacing lead
comprising: an elongated lead body having an body axis extending
therethrough and a first bend defined thereon; a proximal section
having a second bend defined thereon, the proximal section
extending from the first bend and defined between the first and
second bends, such that a first angle less than 90 degrees is
defined between the lead body and proximal section; a tip section
having a tip axis extending therethrough and a tip electrode
disposed thereon, the tip section extending from the second bend,
such that a second angle is defined between the tip and proximal
sections, wherein the pacing lead is configured such that when at
least a portion of the first bend is inserted into the opening of
the coronary sinus, the first angle is operably compressed by the
coronary sinus opening and the tip electrode contacts the wall of
the coronary sinus thereby operably extending the second angle,
wherein when the first bend is inserted into the opening of the
coronary sinus, the tip axis intersects the body axis when the tip
and body axes are projected onto a common plane parallel to and
including the body axis.
17. The lead of claim 16, wherein the first angle defined between
the lead body and proximal section is less than 45 degrees.
18. The lead of claim 16, wherein the second angle defined between
the tip and proximal sections is between 90 and 150 degrees.
19. The lead of claim 16, further comprising a stylet disposed
therein for selectively maintaining the stiffness of the lead as
the lead is inserted into the opening of the coronary sinus.
20. The lead of claim 16, wherein the lead comprises a lead width,
the lead width being between 4 and 6 French.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to pacing leads.
More particularly, the present invention relates to pacing leads
for stable pacing of the left atrium through the coronary
sinus.
BACKGROUND OF THE INVENTION
[0002] Pacing to the left atrium is important for successful
bi-atrial pacing. The pacing to the left atrium is usually
accomplished by placing a pacing lead into the coronary sinus,
which is a venous structure accessible through the right atrium of
the heart and serves to drain the coronary veins. The coronary
sinus is generally wider at its ostium and tapers inwardly away
from the ostium towards the distal portions of the coronary sinus.
The ostium of the coronary sinus is located at the juncture of the
right atrium and the right ventricle.
[0003] To pace the left atrium, a pacing lead can be positioned so
that an electrode contacts the wall of the coronary sinus closest
to the left atrium. Because the coronary sinus is in electrical
contact with the left atrium, by pacing the coronary sinus at this
position, one can also pace the left atrium. The pacing lead
generally is advanced to the ostium of the coronary sinus through
the right atrium portion of the right heart. For effective pacing,
it is desirable that a tip electrode on the pacing lead is placed
directly into constant contact with the left atrial side of the
coronary sinus. By having this constant contact, high voltages, and
thus instability and high thresholds, can be inhibited.
[0004] To accomplish such constant contact, different pacing lead
configurations have been used to assist in the placement and
retention of the pacing lead in the desired position. For example,
leads have been used in which a body of the lead is pre-formed to
have a sinusoidal or helical configuration enabling the lead to
expand into contact with the walls of the coronary sinus and retain
the lead. Examples of such pre-formed coronary sinus leads are
disclosed in U.S. Pat. No. 5,423,865 to Bowald et al. and U.S. Pat.
No. 5,476,498 to Ayers.
[0005] Referring to FIGS. 1a-1f, specific examples of pre-formed
coronary sinus leads are depicted and described in U.S. Pat. No.
6,321,123 to Morris et al, which is incorporated herein by
reference. Pacing leads 20 according to Morris et al. generally
comprise a first curved portion 22, a second curved portion 24, a
tip electrode 26, and additional electrodes 28. A sheath is used to
insert the lead 20 into a coronary sinus. Once the sheath and lead
20 are within the coronary sinus, the sheath is removed and the
lead 20 takes its pre-formed shape. The pre-formed "J" in the lead
20 can cause the tip 26 to be pressed up against the wall of the
coronary sinus, but only if the width of the pre-formed pacing lead
20 is greater than that of the coronary sinus. When the coronary
sinus is wider than the pacing lead 20, the tip electrode can lose
contact with the wall of the coronary sinus. This can lead to
higher voltage requirements during pacing, and thus higher
instability and pacing threshold values.
[0006] Referring to FIG. 2, there are also other pacing leads 30
that can be used to pace the left atrium through the coronary
sinus, such as the Medtronic Attain.RTM. Bipolar OTW Lead Model No.
4194 and leads as disclosed in U.S. Pat. No. 5,683,445 to Swoyer,
both of which are incorporated herein by reference. The pacing lead
30 generally includes a first curved portion 32, a second curved
portion 34, and a tip electrode 36. As depicted in FIG. 2, the
angle 31 at the first curve 32 is greater than ninety degrees. A
sheath is used to insert the lead 30 as depicted in FIG. 2 into a
coronary sinus. Once the sheath and lead 30 are within the coronary
sinus, the sheath is removed and the lead 30 takes its pre-formed
shape. This enables the tip electrode 36 to be contact the walls of
the coronary sinus. However, using these leads to pace the coronary
sinus presents the same problems inherent with the leads according
to Morris et al. in that when the coronary sinus is wider than the
pacing lead, the tip electrode can lose contact with the wall of
the coronary sinus leading to instability and higher pacing
voltages and threshold values
[0007] There is currently a need for a lead assuring stable pacing
of the left atrium through the coronary sinus. Because the general
problems discussed above have not been addressed by conventional
pacing leads, there is a current need for pacing leads addressing
the problems and deficiencies inherent with conventional
designs.
SUMMARY OF THE INVENTION
[0008] The pacing lead of the various embodiments of the present
invention substantially addresses the aforementioned problems of
conventional designs by providing a lead shape and method of pacing
lead deployment that assures that the tip of the lead is firmly in
contact with the left atrial side of the coronary sinus. The
improved pacing is accomplished because as the lead is advanced
into the coronary sinus, the tip electrode is fixed relative to the
coronary sinus closest to the left atrium, thus resulting in lower
pacing voltages and thresholds and higher pacing stability.
[0009] A feature and advantage of embodiments of the invention is
that the left atrium can be paced by directing the tip electrode
towards the left atrium side of the coronary sinus.
[0010] A feature and advantage of embodiments of the invention is
that assuring constant contact between the lead electrodes and the
walls of the coronary sinus can increase the stability of the
pacing.
[0011] A feature and advantage of embodiments of the invention is
that the design of the pacing lead enables for use on various sized
coronary sinuses without sacrificing stability.
[0012] A feature and advantage of embodiments of the invention is a
method of pacing lead deployment assuring constant contact between
the lead electrodes and the walls of the coronary sinus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1a is a fragmentary elevational view of a prior art
coronary sinus pacing lead;
[0014] FIG. 1b-1f are fragmentary cross-sectional views of a
coronary sinus depicting prior art coronary sinus pacing leads
being inserted into the coronary sinus;
[0015] FIG. 2 is a fragmentary elevational view of a prior art
left-ventricle pacing lead;
[0016] FIG. 3 is a fragmentary elevational view of a coronary sinus
pacing lead according to an embodiment of the present
invention;
[0017] FIG. 4 is a fragmentary cross-sectional view of a coronary
sinus depicting a coronary sinus pacing lead according to an
embodiment of the present invention prior to being inserted into
the coronary sinus;
[0018] FIG. 5 is a fragmentary cross-sectional view of a coronary
sinus depicting a coronary sinus pacing lead according to an
embodiment of the present invention being inserted into the
coronary sinus;
[0019] FIG. 6 is a fragmentary cross-sectional view of a coronary
sinus depicting a coronary sinus pacing lead according to an
embodiment of the present invention inserted into the coronary
sinus; and
[0020] FIG. 7 is a fragmentary cross-sectional view of a coronary
sinus depicting a coronary sinus pacing lead according to an
embodiment of the present invention inserted into the coronary
sinus.
DETAILED DESCRIPTION OF THE DRAWINGS
[0021] Referring to FIG. 3, a pacing lead 40 according to the
various embodiments of the present invention generally includes a
main lead portion 42 terminating at a first or proximal curve 44
having a first angle 46, a second or distal curve 50 having a
second angle 52, and a tip electrode 56. A first section 48 is
generally defined between the first and second curves 44, 50 and a
second section 54 is generally defined between the second curve 50
and the tip electrode 56. The pacing lead 40 can also comprise
additional curves and sections disposed between the tip electrode
and the second curve. Pacing leads are generally known in the art
and are disclosed in U.S. Pat. No. 6,321,123 to Morris et al. and
U.S. Pat. No. 5,683,445 to Swoyer, both of which are incorporated
herein by reference in their entirety.
[0022] The pacing lead 40 can also include one or more secondary
coil or ring electrodes 58 disposed at any desired point on the
main lead portion 42 or first or second sections 48, 54. The pacing
lead 40 can further include a stylet 60 to selectively maintain the
stiffness of the pacing lead 40 as the lead 40 is advanced into and
positioned within the coronary sinus. It will also be appreciated
that the shape of tip electrode 56 may be modified as desired, for
example by maximizing contact surface area, to enable better
contact with the wall of the coronary sinus and resultantly better
performance.
[0023] The respective lengths of the first and second sections 48,
54 and the first and second angles 46, 52 between the first and
second sections 48, 54 of the pacing lead 40 can be selected so
that the tip electrode 56 will be in constant contact with the left
atrial wall of the coronary sinus, i.e., to maximize contact
between the tip electrode 46 and the left atrial wall of the
coronary sinus. The overall length L and width W of the first and
second sections 48, 54 can also be selected so that the tip
electrode 56 will be in constant contact with the left atrial wall
of the coronary sinus. The dimensions of the pacing lead according
to exemplary embodiments of the present invention can be seen in
Table I. Generally, the width of the pacing lead is preferably
twice the width of the coronary sinus for stability and good
electrical contact. TABLE-US-00001 TABLE I Pacing lead dimensions
according to various exemplary embodiments. First Exemplary Second
Exemplary Range Embodiment Embodiment Lead Width (French) 2 F to 9
F 5 F .+-. 1 F 5 F .+-. 1 F Width - W (mm) 2.0 to 20.0 7.0 .+-. 5.0
7.0 .+-. 5.0 Length - L (mm) 5.0 to 60.0 30.0 .+-. 5.0 30.0 .+-.
5.0 First Section (mm) 2.0 to 30.0 10 .+-. 5.0 20.0 .+-. [10.0 cm]
Second Section (mm) 2.0 to 30.0 10 .+-. 5.0 20.0 .+-. [10.0 cm]
First angle* (degrees) 90-165 45 .+-. 5 45 .+-. 5 Second angle*
(degrees) 105-165 120 .+-. 30 120 .+-. 30 *Pre-formed angle prior
to insertion into the coronary sinus.
[0024] While dimensions of the pacing lead 40 according to
exemplary embodiments of the present invention are listed in Table
I, one skilled in the art will recognize that changes may be made
in form and detail of the dimensions without departing from the
spirit and the scope of the invention. Therefore, the exemplary
embodiments listed in Table I should be considered in all respects
as illustrative and not restrictive.
[0025] Referring to FIGS. 4-6, implanting the pacing lead 40 into
the coronary sinus can be accomplished by first inserting a stylet
60 into the pacing lead 40 and then advancing the pacing lead 40
with stylet 60 towards the ostium of the coronary sinus.
Introducers for accessing the coronary sinus of the heart can be
seen in U.S. Patent Application Publication Nos. 2003/0208141A1,
2004/0019359A1, and 2003/0208220A1, each to Worley et al., which
are incorporated herein by reference. The implantation can be done
using a guide wire supported guiding catheter 62 having a sheath 64
and guide support wire 66. A guide wire supported guiding catheter
62 is disclosed, for example, in U.S. Pat. No. 6,714,823, which is
incorporated herein by reference. Alternatively, where the coronary
sinus is of a smaller diameter, or where it is desired to pace the
smaller diameter distal portion of the coronary sinus, pacing lead
40 may be inserted tip first using a sheath and stylet.
[0026] To implant the pacing lead 40 using a guiding catheter 62,
one end of the guide wire 66 is first inserted deep into the
coronary sinus. The other end of the guide wire 66 is operably
coupled to the sheath 64 of the guiding catheter 62. The guide wire
66 can then maintain the positioning of the sheath 64 proximate the
ostium of the coronary sinus.
[0027] Once the sheath 64 is held into place proximate the ostium
of the coronary sinus, the stylet 60 of the pacing lead 40 is
withdrawn out of the pacing lead 40 to a position proximate the
first or proximal bend 44 of the pacing lead 40. The pacing lead 40
can then be advanced out of the sheath 64 while maintaining the
stylet 60 at its position proximate the first bend 44 of the lead
40.
[0028] After the pacing lead 40 has been advanced out of the sheath
64 so that the lead 40 takes its pre-formed shape, the stylet 60 is
kept at the first bend 44 of the pacing lead 40 while the lead 40
and stylet 60 are advanced into the coronary sinus, proximal bend
44 first. As stated above in Table I, in a first embodiment of the
present invention, the first angle 46 between the first and second
sections 48, 54, in its pre-formed configuration, is approximately
120 degrees.
[0029] As the pacing lead 40 is inserted into the ostium of the
coronary sinus, the first angle 46 will compress or decrease until
the tip electrode 56 comes into contact with the wall of the
coronary sinus. Once this happens, the second angle 52 between the
first and second sections 48, 54 will increase, e.g., to
approximately one hundred and fifty degrees, due to compressive
forces placed on the tip 56 as the pacing lead 40 progresses into
the narrowing structure of the coronary sinus. In other words, in
this wedged position, the walls of the coronary sinus flatten the
distal curve 50 as the lead 40 is advanced into the tapering
tubular structure of the coronary sinus. The tapering shape of the
coronary sinus maximizes the contact between the tip electrode 56
and left atrium side of the coronary sinus.
[0030] By compressing the proximal and distal curves 44, 50, the
lead 40 folds over and the tip electrode 56 is pressed against the
left atrial side of the coronary sinus, thus improving the contact
between the tip electrode 56 and the wall of the coronary sinus.
Contact between the tip electrode 26 and the coronary sinus is
maintained as the pacing lead 40 expands to assume its natural,
expanded state. The contact results in lower pacing voltages and
thresholds and higher pacing stability. The contact also inhibits
any movement of the pacing lead 40 due to the heart beating and
breathing of the patient once it is in its place within the
coronary sinus. In this position, the coil or ring electrode 58
also has improved contact with the wall of the coronary sinus, as
depicted in FIG. 7.
[0031] While insertion of the pacing lead 40 into the coronary
sinus has been depicted and described as being done by first
advancing the lead 40 out of the sheath 64 until the lead 40 takes
its pre-formed shape, in other embodiments, such as where the
coronary sinus has a smaller diameter, the pacing lead 40 can be
introduced tip-first in the coronary sinus in the conventional
fashion prior to advancing the advancing the lead 40 out of the
sheath 64.
[0032] Although the present invention has been described with
reference to particular embodiments, one skilled in the art will
recognize that changes may be made in form and detail without
departing from the spirit and the scope of the invention.
Therefore, the illustrated embodiments should be considered in all
respects as illustrative and not restrictive.
* * * * *