U.S. patent application number 16/819664 was filed with the patent office on 2020-07-09 for catheter with high-density mapping electrodes.
The applicant listed for this patent is St. Jude Medical, Cardiology Division, Inc.. Invention is credited to Travis Dahlen, Rishi Manda.
Application Number | 20200214635 16/819664 |
Document ID | / |
Family ID | 66097276 |
Filed Date | 2020-07-09 |
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United States Patent
Application |
20200214635 |
Kind Code |
A1 |
Dahlen; Travis ; et
al. |
July 9, 2020 |
Catheter with High-Density Mapping Electrodes
Abstract
High-density mapping catheters with an array of mapping
electrodes are disclosed. These catheters can be used for
diagnosing and treating cardiac arrhythmias, for example. The
catheters are adapted to contact tissue and comprise a flexible
framework including the electrode array. The array of electrodes
may be formed from a plurality of columns of longitudinally-aligned
and rows of laterally-aligned electrodes.
Inventors: |
Dahlen; Travis; (Forest
Lake, MN) ; Manda; Rishi; (Stillwater, MN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
St. Jude Medical, Cardiology Division, Inc. |
St. Paul |
MN |
US |
|
|
Family ID: |
66097276 |
Appl. No.: |
16/819664 |
Filed: |
March 16, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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PCT/US2018/054084 |
Oct 3, 2018 |
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16819664 |
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62572186 |
Oct 13, 2017 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 5/6858 20130101;
A61B 5/0422 20130101; A61B 2018/00351 20130101; A61B 2018/00839
20130101; A61B 2562/221 20130101; A61B 5/6869 20130101; A61B
2218/002 20130101; A61B 5/6859 20130101; A61N 1/362 20130101; A61B
2018/00267 20130101; A61B 18/1492 20130101; A61B 2018/0016
20130101; A61B 2018/00357 20130101; A61B 2217/007 20130101; A61B
2018/00577 20130101 |
International
Class: |
A61B 5/00 20060101
A61B005/00; A61B 5/042 20060101 A61B005/042; A61B 18/14 20060101
A61B018/14 |
Claims
1. A planar array catheter comprising: an elongated catheter shaft
including a proximal end and a distal end, and defining a catheter
longitudinal axis extending between the proximal and distal ends;
and a flexible, planar array at the distal end of the catheter
shaft, the planar array configured to conform to tissue, and
includes two or more arms extending substantially parallel with the
longitudinal axis, each of the arms having a plurality of
electrodes mounted thereon; and wherein the electrodes on each arm
are grouped into cliques of three or more electrodes defining a
two-dimensional shape.
2. The planar array catheter of claim 1, wherein the plurality of
electrodes on each arm are configured in at least two columns
oriented substantially parallel with the longitudinal axis.
3. The planar array catheter of claim 1, wherein the cliques of
electrodes are configured in a triangular-shape, each clique having
at least three electrodes, the clique of electrodes configured to
sample electrical characteristics of contacted tissue in at least
two substantially transverse directions.
4. The planar array catheter of claim 1, wherein each arm of the
planar array includes electrodes on both an inner and outer
surface, each of the cliques including at least one electrode on an
inner surface of the arm, the at least one electrode on the inner
surface of the arm configured to facilitate sampling of electrical
characteristics in a direction normal to the contacted tissue.
5. The planar array catheter of claim 1, wherein the distance
between at least two pairs of electrodes within each clique is
equal.
6. The planar array catheter of claim 1, wherein the distance
between the electrodes in each clique is constant in contracted and
deployed configurations of the planar array.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of Patent Cooperation
Treaty application no. PCT/US2018/054084 ("the '084 PCT"), filed 3
Oct. 2018, now pending, which claims the benefit of U.S.
provisional application No. 62/572,186 ("the '186 provisional),
filed 13 Oct. 2017. The '084 PCT and '186 provisional are hereby
incorporated by reference as though fully set forth herein.
BACKGROUND
[0002] a. Field
[0003] The instant disclosure relates to high-density
electrophysiology mapping catheter assemblies and to map-ablate
catheter assemblies for diagnosing and treating cardiac arrhythmias
via, for example, radiofrequency ablation. In particular, the
instant disclosure relates to flexible high-density mapping
catheter assemblies, and to flexible ablation catheter assemblies
including onboard, high-density mapping electrodes.
[0004] b. Background Art
[0005] Intravascular catheters have been used for non-invasive
cardiac medical procedures for many years. Catheters may be used,
for example, to diagnose and treat cardiac arrhythmias, while
positioned within a patient's vasculature that is otherwise
inaccessible without a more invasive procedure.
[0006] Conventional electrophysiology mapping catheters may
include, for example, a plurality of adjacent ring electrodes
encircling a longitudinal axis of the catheter and constructed from
platinum or some other metal. These ring electrodes may be
relatively rigid. Similarly, conventional ablation catheters may
comprise a relatively rigid tip electrode for delivering therapy
(e.g., delivering RF ablation energy) and may also include a
plurality of adjacent ring electrodes. In many applications, it can
be difficult to maintain good electrical contact with cardiac
tissue when using these conventional catheters and their relatively
rigid (or nonconforming), metallic electrodes, especially when
sharp gradients and undulations are present.
[0007] Whether mapping or forming lesions in a heart, the beating
of the heart, especially if erratic or irregular, complicates
matters, making it difficult to keep adequate contact between
electrodes and tissue for a sufficient length of time. These
problems are exacerbated on contoured or trabeculated surfaces. If
contact between the electrodes and tissue cannot be sufficiently
maintained, quality lesions or accurate mapping are unlikely to
result.
[0008] The foregoing discussion is intended only to illustrate the
present field and should not be taken as a disavowal of claim
scope.
BRIEF SUMMARY
[0009] The instant disclosure relates to high-density
electrophysiology mapping catheter assemblies and to map-ablate
catheter assemblies for diagnosing and treating cardiac arrhythmias
via, for example, radio-frequency ablation. In particular, the
instant disclosure relates to flexible high-density mapping
catheter assemblies, and to flexible ablation catheter assemblies
including onboard high-density mapping electrodes.
[0010] Aspects of the present disclosure are directed to basket
catheters including an elongated catheter shaft with proximal and
distal ends, a flexible basket catheter with a plurality of
splines, and a plurality of electrodes mounted to the splines. The
flexible basket catheter is coupled to the distal end of the
catheter shaft and conforms to tissue when extended into a deployed
configuration. The plurality of electrodes are further organized
into triangular-shaped cliques along each of the splines. In more
specific embodiments, each of the splines nest with adjacent
splines when the flexible basket catheter is actuated into a
contracted configuration.
[0011] Some embodiments are directed to a planar array catheter
including an elongated catheter shaft with proximal and distal
ends. The elongated catheter shaft defines a catheter longitudinal
axis extending between the proximal and distal ends. The planar
array catheter further includes a flexible, planar array coupled to
the distal end of the catheter shaft. The planar array conforms to
tissue, and includes two or more arms extending substantially
parallel with the longitudinal axis. Each of the arms has a
plurality of electrodes mounted thereon. The electrodes on each arm
are grouped into cliques of three or more electrodes defining a
two-dimensional shape. In some specific embodiments, the plurality
of electrodes on each arm are situated in at least two columns
oriented substantially parallel with the longitudinal axis.
[0012] Various embodiments of the present disclosure are directed
to a linear catheter including an elongated catheter shaft with
proximal and distal ends, and a flexible, distal tip assembly at
the distal end of the catheter shaft. The distal tip assembly
conforms to tissue, and includes a plurality of electrodes. The
plurality of electrodes are grouped into cliques of three or more
electrodes, with each clique sampling the electrical
characteristics of contacted tissue in at least two substantially
transverse directions. In such embodiments, the center-to-center
distance between the electrodes in each clique may be between 0.5
and 4 millimeters. In various specific embodiments, the electrical
characteristics sampled by the electrodes in the clique are
collectively indicative of the true electrical characteristics of
the contacted tissue independent of the orientation of the linear
catheter relative to the tissue.
[0013] The foregoing and other aspects, features, details,
utilities, and advantages of the present disclosure will be
apparent from reading the following description and claims, and
from reviewing the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Various example embodiments may be more completely
understood in consideration of the following detailed description
in connection with the accompanying drawings, in which:
[0015] FIG. 1A a plan view of a tip portion of a planar array
catheter for high-density electrophysiology mapping, consistent
with various embodiments of the present disclosure.
[0016] FIG. 1B is an isometric side view of the tip portion of the
planar array catheter of FIG. 1A depicted in a flexed
configuration, consistent with various embodiments of the present
disclosure.
[0017] FIG. 1C is a close-up, isometric view of an arm portion of
the planar array catheter of FIG. 1A, consistent with various
embodiments of the present disclosure.
[0018] FIG. 1D is a cross-sectional, side view of the planar array
catheter of FIG. 1A, consistent with various embodiments of the
present disclosure.
[0019] FIG. 2A is a partial, isometric view of a high-density
mapping catheter, consistent with various embodiments of the
present disclosure.
[0020] FIG. 2B is a partial, isometric view of the high-density
mapping catheter shown in FIG. 2A depicted in a flexed
configuration, representing contact between the catheter tip and
cardiac tissue, consistent with various embodiments of the present
disclosure.
[0021] FIG. 2C is a partial view of a flat pattern design of an
electrode carrier band on the high-density mapping catheter shown
in FIG. 2A, consistent with various embodiments of the present
disclosure.
[0022] FIG. 3A is a partial, isometric view of a tip region of an
ablation catheter having distal high-density mapping electrodes,
consistent with various embodiments of the present disclosure.
[0023] FIG. 3B is an enlarged, partial view of the distal tip of
the ablation catheter of FIG. 3A, consistent with various
embodiments of the present disclosure.
[0024] FIG. 4A is a plan view of a basket catheter in an expanded
configuration, consistent with various embodiments of the present
disclosure.
[0025] FIG. 4B is a plan view of the basket catheter of FIG. 4A in
a contracted configuration, consistent with various embodiments of
the present disclosure.
[0026] FIG. 4C is an enlarged, plan view of a spline section of the
basket catheter of FIG. 4A, consistent with various embodiments of
the present disclosure.
[0027] FIG. 5A is a plan view of a basket catheter in an expanded
configuration, consistent with various embodiments of the present
disclosure.
[0028] FIG. 5B is a plan view of the basket catheter of FIG. 5A in
a contracted configuration, consistent with various embodiments of
the present disclosure.
[0029] FIG. 5C is an enlarged, plan view of a spline section of the
basket catheter of FIG. 5A, consistent with various embodiments of
the present disclosure.
[0030] FIG. 5D is an enlarged, top view of the basket catheter of
FIG. 5A, consistent with various embodiments of the present
disclosure.
[0031] FIG. 6A is a plan view of a basket catheter spline,
consistent with various embodiments of the present disclosure.
[0032] FIG. 6B is an enlarged, plan view of a portion of the basket
catheter spline of FIG. 6A, consistent with various embodiments of
the present disclosure.
[0033] FIG. 7A is a plan view of a basket catheter spline,
consistent with various embodiments of the present disclosure.
[0034] FIG. 7B is an enlarged, plan view of a portion of the basket
catheter spline of FIG. 7A, consistent with various embodiments of
the present disclosure.
[0035] FIG. 8A is a plan view of two interleaved basket catheter
splines, consistent with various embodiments of the present
disclosure.
[0036] FIG. 8B is an enlarged, plan view of a portion of the two
interleaved basket catheter splines of FIG. 8A, consistent with
various embodiments of the present disclosure.
[0037] While various embodiments discussed herein are amenable to
modifications and alternative forms, aspects thereof have been
shown by way of example in the drawings and will be described in
detail. It should be understood, however, that the intention is not
to limit the invention to the particular embodiments described. On
the contrary, the intention is to cover all modifications,
equivalents, and alternatives falling within the scope of the
disclosure including aspects defined in the claims. In addition,
the term "example" as used throughout this application is only by
way of illustration, and not limitation.
DETAILED DESCRIPTION OF EMBODIMENTS
[0038] Various embodiments of the present disclosure are directed
to flexible, high-density electrophysiology mapping catheters and
map-ablate catheters. In general, the distal portions of these
various catheters may comprise an underlying support framework that
is adapted to conform to and remain in contact with tissue (e.g., a
beating heart wall).
[0039] Aspects of the present disclosure are directed toward planar
array catheters and basket catheters for electrophysiology mapping.
More specifically, many embodiments of the present disclosure
utilize printed circuit boards (e.g., flexible printed circuit
boards) to form the planar array arms and/or basket splines.
Further, aspects of the present disclosure include a plurality of
electrodes positioned along the planar array arms and/or basket
splines. In such embodiments, the planar array arms and/or basket
splines may have electrodes conductively coupled to the flexible
circuit boards that at least partially form arms and/or splines.
Resulting cliques (or groups) of independently addressable
electrodes facilitate electrophysiology measurements of tissue, in
contact with the electrodes, which are orientation independent.
That is, measurements may be taken across bi-pole pairs of
electrodes within each clique (with a known distance therebetween)
to capture measurements in at least two orthogonal orientations. In
more advanced three-dimensional electrogram analysis,
electrophysiology measurements may be captured in three orthogonal
planes. In some embodiments, it may be desirable for the electrodes
of a clique to be placed equidistant one another to facilitate
enhanced electrogram fidelity.
[0040] Aspects of the present disclosure are directed toward
various high-density electrode array catheters with substantially
uniform electrode spacing and/or known and constant spacing between
electrodes. The array of electrodes includes a plurality of bi-pole
pairs that facilitate electrophysiology mapping of tissue in
contact with the electrodes. More advanced embodiments of the
present disclosure may utilize orientation independent
sensing/omnipolar technology ("OIS/OT") and related algorithms to
mitigate the need for substantially square electrode arrays. OIS/OT
and related algorithms are discussed in more detail in U.S.
provisional application No. 61/944,426, filed 25 Feb. 2014, U.S.
application Ser. No. 15/118,522, filed 25 Feb. 2015, and
international application no. PCT/US2014/011940, filed 16 Jan.
2014, all of which are hereby incorporated by referenced as though
fully disclosed herein.
[0041] Conventional mapping catheter designs employ bi-pole
electrode configurations to detect, measure, and display electrical
signals from the heart. However, such conventional mapping catheter
designs may be prone to error associated with the orientation of
the bi-pole electrode pairs relative to an electrical wavefront of
the heart, and result in sensed electrical signals and
electrophysiology mapping results that may be orientation
dependent; and accordingly may not actually reflect the tissue
properties. To mitigate this risk, aspects of the present
disclosure are directed to signal processing techniques which may
sample a plurality of bi-pole electrode pair configurations, with
varying orientations, to produce electrophysiology mapping results
which are independent of orientation. To facilitate such signal
processing techniques, respective electrophysiology mapping
catheters (e.g., linear, planar array, and basket) may utilize
cliques of electrodes with spacing that is constant over time.
[0042] Various embodiments of the present disclosure are directed
to electrophysiology mapping catheters, such as linear arrays and
basket catheters, where each spline and/or arm includes more than
one column of electrodes extending a length of the
catheter--negating the need to take measurements across
splines/arms. This greatly improves the accuracy of the resulting
electrical signal maps, as the relative distance of electrodes on
the same arm/spline are not prone to changes in distance over time
as electrodes on adjacent arms/splines. Moreover, the
electrophysiology basket catheters, during a diagnostic procedure,
may be operated anywhere between an expanded and contracted state
as the relative distance between electrodes within a clique on each
arm/spline does not change during movement of the catheter
arms/splines, or in response to tissue contact.
[0043] Further aspects of the present disclosure are directed
toward eliminating a distal cap of an electrophysiology basket
catheter, which facilitates the sampling of electrogram data from
the distal most tip of the basket.
[0044] Details of the various embodiments of the present disclosure
are described below with specific reference to the figures.
[0045] FIG. 1A is a plan view of a tip portion 110 of a planar
array catheter 101 for high-density electrophysiology mapping,
consistent with various embodiments of the present disclosure. The
tip portion 110 includes a flexible array of (micro)electrodes
102.sub.1-N distributed along a top surface of arms 103, 104, 105,
106. The four longitudinally-extending arms comprise the flexible
framework of the planar array. In various embodiments of the
present disclosure, the arms 103, 104, 105, 106 are flexible
printed circuit boards. In the present embodiment, each arm
includes two columns of electrodes 102.sub.1-N extending a length
of the arms. The relative spacing of the electrodes, in some
embodiments, may be between 1.5-3 millimeters (center-to-center
spacing). While various embodiments of the present disclosure are
directed to spot electrodes that are printed on flexible circuit
boards, such embodiments may be readily adapted to facilitate the
use of ring electrodes on the arms 103, 104, 105, 106 with the
position and spacing disclosed herein. The four arms 103, 104, 105,
106 comprise a first outboard arm 103, a second outboard arm 106, a
first inboard arm 104, and a second inboard arm 105. These arms may
be laterally separated from each other (when deployed) by
approximately 3.3 millimeters ("mm"), for example. In some specific
embodiments, the relative spacing of the electrodes 102.sub.1-N may
be 1 mm or less. Although the planar array depicted herein includes
four arms 103, 104, 105, 106, other embodiments with varying
numbers of arms, relative electrode spacing, the number of total
electrodes on each arm, the number of rows and columns of
electrodes on each arm, and placement of electrodes on one or both
sides of the planar array are readily adaptable and envisioned by
the present disclosure.
[0046] Consistent with the embodiment disclosed in FIG. 1A, some
specific embodiments of the planar array catheter may include
electrodes of varying sizes. For example, the most-distal electrode
102 on the first outboard arm 103 and/or the most-proximal
electrode 102 on the second outboard arm 106 may be larger in
surface area. These enlarged electrodes may be used, for example,
for precise localization of the flexible array in impedance-based
navigation systems. In some embodiments, the larger electrodes may
facilitate tissue ablation. In such an embodiment, the larger
electrodes may be driven with an ablation current between two or
more of the larger electrodes, if desired, for bipolar ablation,
or, alternatively to drive ablation current in a unipolar mode
between one or both of the enlarged electrodes and, for example, a
patch electrode located on a patient (e.g., on the patient's back).
Unipolar or bipolar ablation may also be conducted between the
smaller electrodes and/or a combination of smaller and larger
electrodes 102. Alternatively or concurrently, current may travel
between one or more of the enlarged electrodes and any one or all
of the smaller electrodes. This unipolar or bipolar ablation may be
used to create specific lines or patterns of lesions.
[0047] As further shown in FIG. 1A, a catheter shaft 107 is coupled
to a tip portion 110 (including the planar array) via a proximal
bushing 108 which receives the one or more arms 103, 104, 105, 106
of the planar array. A distal portion of the catheter shaft 107 may
include radiopaque marker bands 111 to facilitate fluoroscopic
visualization of the catheter within a patient's cardiovascular
system. In other embodiments, the radiopaque marker bands 111 may
be localization coils to facilitate visualization of the planar
array in an impedance-based, magnetic-based, or hybrid type
navigation system (e.g., such as the MediGuide.TM. System sold by
Abbott Laboratories). In further embodiments, the planar array may
include a combination of radiopaque marker bands and localization
coils.
[0048] FIG. 1B is an isometric side view of the tip portion 110 of
the planar array catheter 101 of FIG. 1A for high-density
electrophysiology mapping and is depicted in a flexed configuration
(representing contact between the catheter tip and cardiac tissue),
consistent with various embodiments of the present disclosure. In
FIG. 1B, the planar, flexible arms 103, 104, 105, 106 are flexed to
conform to the cardiac tissue (not shown), enabling a physician to
maintain contact between several of the electrodes 102.sub.1-N and
the tissue. This enhances the accuracy, and the corresponding
diagnostic value, of the recorded information concerning the
heart's electrical activity.
[0049] While many embodiments of the present disclosure are
directed to electrophysiology mapping, embodiments of the present
disclosure may also be configured for pacing (as well). For
example, one or more electrodes 102.sub.1-N may send pacing signals
to, for example, cardiac tissue.
[0050] While some embodiments are directed to a planar array
structure substantially comprising flexible printed circuits, the
arms 103, 104, 105, 106 may alternatively (or in addition to)
include (or be reinforced with) a flexible or spring-like material
such as nitinol. The construction (including, for example, the
length and/or diameter of the arms) and material composition of the
arms may be tailored for specific applications. For example,
desired resiliency, flexibility, foldability, conformability, and
stiffness characteristics (including one or more characteristics
that may vary from the proximal end of a single arm to the distal
end of that arm, or between or among the plurality of arms
comprising the planar array). The foldability of materials such as
nitinol, or flexible circuit board materials (e.g., thin polymer
films) provides the additional advantage of facilitating insertion
of the planar array into a delivery catheter or introducer, whether
during delivery of the catheter into the body or removal of the
catheter from the body at the end of a procedure.
[0051] The high-density electrode configuration of the various
electrophysiology mapping catheters disclosed herein may find
particular application for (1) defining regional propagation maps
on, for example, one millimeter square areas within the atrial
walls of the heart; (2) identify complex fractionated atrial
electrograms for ablation; (3) identify localized, focal potentials
between the electrodes for higher electrogram resolution; and/or
(4) more precisely target areas for ablation. The mapping catheters
and ablation catheters disclosed herein are constructed to conform
to, and remain in contact with, cardiac tissue despite (potentially
erratic) cardiac motion. The contact stability of the catheters
disclosed herein during cardiac motion facilitates improved mapping
accuracy and ablation contiguity due to sustained tissue-electrode
contact. While various embodiments of the present disclosure are
presented in terms of endocardial applications, the catheters
described herein may also be directed for use in epicardial
applications.
[0052] Though not shown in FIGS. 1A-B, various embodiments of the
planar array catheter 101 may include one or more irrigation ports.
For example, a proximal irrigant port(s) may be located on/at the
distal end of proximal bushing 108, the proximal irrigant port(s)
positioned to deliver irrigant to or near the point where the
electrode carrying arms 103, 104, 105, 106 exit from the distal end
of the proximal bushing 108 that is mounted on the distal end of
the catheter shaft 107 in this embodiment. In some more specific
embodiments, a second, distal irrigation port(s) may be located
near the distal intersection of the arms 103, 104, 105, 106 and on
or near distal tip 109. In yet further embodiments, if desired,
multiple irrigation ports could be present at various positions
along the arms 103-106. Where more than one irrigant port is
positioned at proximal and/or distal ends of the planar array 110,
more uniform irrigant distribution at or near the proximal/distal
apex of the arms 103-106 may be facilitated.
[0053] FIG. 1C is a close-up, isometric view of a portion of arm
106 of the high-density mapping catheter 101 of FIG. 1A, consistent
with various embodiments of the present disclosure. The arm 106
includes two columns of electrodes 102.sub.1-N extending along a
length of the arm. Each set of three adjacent electrodes forms a
clique of electrodes 112.sub.1-3. Each clique is capable of mapping
the electrophysiology of tissue in contact therewith in a manner
that is independent of the orientation of an individual bi-pole
electrode pair within the clique used to sense the electrical
characteristics of the tissue. Specifically, the cliques are
capable of sampling the electrical signal passing through the
contact tissue in at least two orientations. For example, a first
bi-pole pair of electrodes in an example clique 112.sub.1 samples
an electrical signal passing through the contact tissue in an
x-orientation, and a second bi-pole pair of electrodes in the
clique 112.sub.1 samples a second electrical signal passing through
the contact tissue in a y-orientation. Signal processing circuitry
may then be used to determine the true electrical signal for that
location. The two bi-pole pairs, though substantially in the same
location and in contact with the same tissue volume, may sample
different electrical characteristics of the tissue due to the
directionality of the electrical activation wave fronts traveling
through the heart. The electrical activation wave fronts typically
emanate from a sinoatrial node, and atrioventricular node; however,
interfering electrical signals may also emanate from one or more of
the pulmonary veins.
[0054] Importantly, to facilitate determination of important
electrical characteristics of the tissue (e.g., impedance), the
distance between the first bi-pole pair (D.sub.A) and the distance
between the second bi-pole pair (D.sub.B) must be known and/or
constant. In FIGS. 1A-D, the spacing of electrodes 102.sub.1-N on
arms 103-106 is constant. Furthermore, in various embodiments it
may be desirable for the distance between the two sets of bi-pole
pairs for a single clique 112 to be the same (D.sub.A=D.sub.B).
[0055] FIG. 1D is a cross-sectional, side view of an arm 106 of the
planar array catheter 101 of FIG. 1A, consistent with various
embodiments of the present disclosure. As shown in FIG. 1D, some
embodiments of the planar array catheter 101 may include a
complimentary set of electrodes to the two columns of electrodes
102.sub.1-N mounted on a top surface 198 of the arm 106. The second
set of electrodes 102'.sub.1-N facilitates both electrophysiology
mapping with either side of the planar array, as well as the
ability to detect electrical signal flow through the cardiac muscle
in a z-orientation. As discussed in reference to FIG. 1C, a set of
electrode cliques 112.sub.1-3 on a top surface 198 of the planar
array may detect electrical signal flow through the cardiac tissue
in x and y orientations, while another electrode 102' on the bottom
surface 199 of the planar array (when used in conjunction with one
of the electrodes 102 of the same clique on the top surface 198)
facilitates determination of electrical characteristics in the
z-orientation. FIG. 1D shows a number of cliques 112.sub.4-6 from a
cross-sectional, side view of the planar array catheter 101.
Similar to the positioning of the electrodes 102 on the top surface
198, it is desirable for the distance between the bottom electrodes
102' (D.sub.B), and the depth of the circuit board (D.sub.C) to be
known. Furthermore, in various embodiments it is desirable for the
distance between the two sets of bi-pole pairs for a single clique
112' to be the same (D.sub.B=D.sub.C).
[0056] FIG. 2A is a partial, isometric view of a linear,
high-density mapping catheter assembly portion 210, consistent with
various embodiments of the present disclosure. As shown in FIG. 2A,
the tip portion 210 includes interlocking rings or bands 212 of
non-conductive material (e.g., polyether-etherketone also referred
to as PEEK) forming the underlying support framework for a
plurality of electrodes 218. In this embodiment, a circumferential
or helical through-cut pattern 214 defines a plurality of dovetail
surfaces 216. Each dovetail surface 216 has an electrode 218
attached to it, thereby defining a flexible array of electrodes
that are arranged in circumferential rings or bands about the tip
portion 210 of the linear mapping catheter. The electrodes 218 are
also aligned in longitudinally-extending (e.g., parallel to a
catheter longitudinal axis 220) rows of electrodes that are able to
flex or move slightly relative to each other during use of the
catheter (e.g., contact with tissue). The non-conductive material
of the bands 212 individually insulates each electrode 218 from one
another. The non-conductive substrate on which the electrodes 218
are mounted may comprise PEEK. In some embodiments, the tip 210 may
include a radiopaque tip cap 222 that facilitates fluoroscopic
visualization. The tip cap may be dome shaped, hemispherical,
flat-topped, tapered, or any other desired general shape.
[0057] In the embodiment of the tip portion 210 shown in FIG. 2A-C,
there are approximately sixty-four discrete electrodes 218, and
either separate lead wires that extend to each of the electrodes
218 from the proximal end of the catheter or one or more flexible
circuit boards within the tip portion 210 that are
electrically/communicatively coupled to each of the electrodes 218
and signal processing circuitry (located near a proximal end of the
catheter). In some embodiments, the catheter may be either 7 French
or 7.5 French in diameter. The flexible tip 210 helps to facilitate
sustained electrode contact with cardiac tissue during, for
example, cardiac motion, which in turn improves the accuracy of the
resulting cardiac electrical activity map. The circumferential or
helical cuts 214, which may be formed by a laser, create a
plurality of serpentine gaps that permit the tip to flex as the
cardiac wall moves in a beating heart. When a plurality of
circumferential through-cuts are used, a plurality of dovetailed
(or `saw-toothed`) bands 212 are formed.
[0058] As in the previous embodiments, each of the electrodes 218
are positioned equidistant relative to one another, or at least at
known or constant distances relative to one another.
[0059] FIG. 2B is a partial, isometric view of the high-density
mapping catheter assembly portion 210 shown in FIG. 2A, depicted in
a flexed configuration. The flexed configuration representing
contact between the catheter tip 210 and cardiac tissue. While in
contact with tissue, the resulting flex of the flexible tip 210
along the helical cuts 214 between each of the dovetailed bands 212
creates minute changes in the relative positions of the electrodes
218. As the total flexure of the tip 210 is divided across a
plurality of electrode bi-pole pairs, the total effect on the
resulting cardiac electrical activity map is greatly mitigated.
[0060] The linear, high-density mapping catheter of FIGS. 2A-B may
include an irrigated configuration. In the irrigated configuration,
the catheter may include irrigant ports that extend through the
dovetailed bands 212 and/or irrigant may be excreted through the
helical cuts 214 (serpentine gaps) between interleaving pairs of
the dovetailed bands 212.
[0061] FIG. 2C is a partial view of a flat pattern design of an
electrode carrier band (also referred to as a dovetailed band) 212
on the high-density mapping catheter shown in FIG. 2A, consistent
with various embodiments of the present disclosure.
[0062] As shown in FIG. 2C, the pattern includes a circumferential
waistline or ring 224 defined between a circumferentially-extending
proximal edge 226 and a circumferentially-extending distal edge
228. Each of these edges is interrupted by a plurality of
proximally-extending pads 230 or distally-extending pads 232. Each
pad in this embodiment has the shape of a truncated isosceles
triangle with sides S and a base B. Two adjacent
proximally-extending pads define a proximally-opening pocket 234
between them. Similarly, on the opposite side of the
circumferential waistline 224, two distally-extending pads 232 that
are adjacent to each other define a distally-opening pocket
236.
[0063] When two dovetail bands 212 are connected, each
distally-extending pad 232 flexibly interlocks in a
proximally-opening dovetailed pocket 234 (of the adjacent dovetail
band 212), and each proximally-extending pad 230 flexibly
interlocks in a distally-opening dovetail pocket 236 (of another
adjacent dovetail band 212). The interlocking pads 230 and 232, and
pockets 234 and 236, of each band 212 define a plurality of
serpentine gaps between alternating electrode-carrier bands 212
which facilitate deformation of the catheter tip 210 in response to
a force exerted on the tip. In the present embodiment, each of the
pads 230, 232 includes an aperture 238 in which an electrode will
be mounted. Each aperture 238 may extend through the respective
pad, from a pad outer surface to a pad inner surface.
[0064] In other embodiments, instead of circumferential
through-cuts 214 (see, e.g., FIGS. 2A-B), which define a plurality
of individual electrode-carrier bands 212, the flexible tip may be
formed by a continuous helical cut.
[0065] While the embodiments of FIGS. 2A-C show bands 212 with
longitudinally offset pads 230 and 232 on either side of waistline
224, other embodiments may include a carrier band with a plurality
of bowtie-shaped or hourglass-shaped structures extending across
the waistline 224 (instead of the offset pads 230 and 232). Each of
the bowtie-shaped or hourglass-shaped structures having
electrode-mounting apertures 238 on one or more sides of the
waistline 224. Such embodiments are essentially symmetrical about
the waistline 224, except where electrode-mounting apertures are
placed only on one side of the bowtie-shaped or hourglass-shaped
structures.
[0066] As shown in FIG. 2C, each band 212 includes two columns of
electrodes, with each electrode coupled to a respective
electrode-mounting aperture 238. The two columns of electrodes
extending along a waistline 224 of the band 212, with the relative
placement of the electrodes in each column longitudinally offset
relative to one another. The resulting formation creates a
plurality of triangular cliques of electrodes 213.sub.1-3 formed
from three adjacent electrodes. Each clique 213 is capable of
mapping the electrophysiology of tissue in contact therewith, in a
manner that is independent of the orientation of a single bi-pole
electrode pair. Specifically, the triangular cliques 213 of the
present embodiment are capable of sampling the electrical signal
passing through the contact tissue in three directions (offset from
one another by approximately 60.degree.). Signal processing
circuitry may then be used to determine the true electrical signal
characteristics for that location, regardless of bi-pole pair
sampling orientation. Importantly, to facilitate determination of
important electrical characteristics of the tissue (e.g.,
impedance), the distance between the first bi-pole pair (D.sub.E),
second bi-pole pair (D.sub.F), and third bi-pole pair (D.sub.G)
must be known and constant. In FIG. 2C, the spacing of the
electrodes on the band 212 are not only known and constant, but the
spacing between each of the electrodes in the clique 213 are equal.
Accordingly, the distance between each of the three sets of bi-pole
pairs for the clique 213.sub.1 are equal
(D.sub.E=D.sub.F=D.sub.G).
[0067] The relative spacing of the electrode mounting apertures 238
in FIG. 2C (and thereby the electrodes), in some embodiments, may
be between 1.5-3 millimeters (center-to-center spacing). In some
specific embodiments, the relative spacing of the electrode
mounting apertures 238 may be 1 mm or less.
[0068] FIG. 3A is a partial, isometric view of a tip portion 310 of
an ablation catheter having distal high-density mapping electrodes
and FIG. 3B is an enlarged, partial view of the distal tip of the
ablation catheter of FIG. 3A, consistent with various embodiments
of the present disclosure.
[0069] As shown in FIGS. 3A-B an ablation catheter tip portion 310
is depicted with an interlocking, dovetailed pattern 356 formed
from conductive material to facilitate tissue ablation of contacted
tissue via thermal/electrical energy transfer. Each of the
dovetailed patterns 356 that extend circumferentially about the tip
portion 310 are separated by a serpentine cut 354. The distal end
344 of this flexible ablation tip 310 includes a pair of
symmetrically-placed, high-density microelectrodes 346 for
electrophysiology mapping. The distal end further includes two
front-facing irrigation ports 348, and a thermocouple or
temperature sensor 350. The mapping electrodes 346 may be mounted
in a nonconductive insert 352 (as shown in FIG. 3B) to electrically
insulate the mapping electrodes from the remainder of the ablation
tip. In such a configuration, the flexible ablation tip 310 may be
approximately 4-8 millimeters long. In the embodiment of FIGS.
3A-B, the pads and pockets of the interlocking, dovetailed pattern
356 defined by the serpentine cuts 354 may be smaller than the
corresponding pads and pockets depicted in, for example, FIGS.
2A-C, the individual pads of the tip portion 310 do not house
electrodes. Though in other embodiments, the pads and pockets of
FIGS. 2A-C may be combined with the distal end 344 of FIG.
3A--facilitating two arrays of high-density electrodes on a single
catheter.
[0070] In some embodiments of the ablation catheter tip portion 310
of FIGS. 3A-B, the irrigant ports 348 may be replaced with
additional mapping electrodes 346. The resulting square pattern of
the mapping electrodes 346 facilitates the use of the electrodes in
bi-pole pair arrangements. With three or more mapping electrodes,
forming a clique, on the distal end 344 of the tip portion 310, the
resulting bi-pole pair arrangements may be independently
addressable to facilitate determination of electrical
characteristics in both x and y directions. To further facilitate
measuring electrical characteristics in a z-direction, one or more
mapping electrodes may be placed on a shaft of the ablation
catheter (at approximately the same center-to-center spacing as the
other mapping electrodes in the clique). Signal processing
circuitry receiving the electrical signals from the electrodes may
then be used to determine the true electrical signal for that
location, independent of the orientation of the bi-pole pairs. In
such embodiments, the distal end 344 may still include irrigant
ports.
[0071] In some embodiments where a z-direction measurement is
desirable, four or more electrodes may be used to form a "pyramid
shaped" clique of electrodes.
[0072] Some specific embodiments, in accordance with the present
disclosure, may combine the embodiments of FIGS. 2A-C, and 3A-B
with a combination of mapping electrodes on a distal end 344
circumferentially and longitudinally extending along a tip portion
210/310 of the catheter shaft. The resulting embodiment facilitates
electrophysiology mapping of tissue in contact with a distal end
344 of the catheter tip portion 310 (as in FIGS. 3A-B) and/or a
distal tip portion of the catheter shaft. This allows the clinician
during an electrophysiology diagnostic procedure to make contact
with target tissue in various relative orientations (e.g.,
perpendicular, parallel, etc.).
[0073] FIG. 4A is a plan view of a distal portion of a basket
catheter 400 in an expanded configuration, consistent with various
embodiments of the present disclosure. The basket is comprised of a
plurality of splines 403, 404, 405, 406 which are coupled to a
catheter shaft 407 at a proximal end and to a distal cap or one
another at a distal end 444. While the present embodiment presents
a basket comprised of four splines 403, 404, 405, 406, basket
catheters with three or more splines are readily envisioned with
the design depending on an intended clinical application and
desired electrophysiology mapping granularity. To facilitate
expansion/contraction of the basket, a deployment member 460
extends along a longitudinal axis of the basket. The deployment
member in some embodiments may be a pull-wire, which extends
proximally to a catheter handle at a proximal end of the catheter
shaft 407. Actuation of the pull-wire causes expansion/contraction
of the basket. In other embodiments, the deployment member 460 may
be a lumen which may be actuated by a manipulator on the catheter
handle to expand/contract the basket.
[0074] In the present embodiment, each of the splines 403, 404,
405, 406 includes electrode islands 461.sub.1-N distributed along a
length of each spline. While the embodiments presented in FIGS.
4A-C depict electrode islands 461.sub.1-N regularly distributed
along the length of each spline, other embodiments may include
electrode islands 461.sub.1-N unevenly distributed along the
splines. For example, in pulmonary vein electrophysiology mapping
applications, only a distal portion of the basket may be in contact
with tissue proximal the pulmonary veins. Accordingly, a
distribution of electrode islands 461.sub.1-N may be weighted
toward a distal end 444 of the basket to facilitate enhanced
electrophysiology mapping granularity in proximity to the pulmonary
veins.
[0075] Various embodiments of the present disclosure are directed
to electrode islands 461.sub.1-N on each of the respective splines
403, 404, 405, 406, with the electrode islands 461.sub.1-N on
adjacent splines being longitudinally offset to facilitate
interleaving when the basket is being delivered via an introducer
sheath in a contracted configuration.
[0076] FIG. 4B is a plan view of a distal portion of the basket
catheter 400 of FIG. 4A in a contracted configuration, consistent
with various embodiments of the present disclosure. Small
serpentine gaps 454 are located between each of the adjacent
splines 403, 404, 405, 406. In the contracted configuration of the
basket catheter, a deployment member 460 (as shown in FIG. 4A) may
be extended distally to allow each of the splines to be drawn in
radially to a longitudinal axis of the catheter shaft 407. In
various embodiments of the present disclosure, the splines 403,
404, 405, 406 may have a natural set in either an
expanded/contracted state, and utilize the deployment member 460 to
overcome the natural set.
[0077] As shown in FIG. 4B, electrode islands 461.sub.1-N on
adjacent splines 403, 404, 405, 406 are longitudinally offset to
facilitate interleaving (also referred to as interlocking or
nesting) the electrode island minimizing collapsed basket catheter
package size. To facilitate the collapsed state of the splines 403,
404, 405, 406, the relative distance between catheter shaft 407 and
distal end 444 is increased via deployment member 460.
[0078] FIG. 4C is an enlarged, plan view of a portion of spline 405
of FIG. 4A. The enlarged, plan view further shows one of the
plurality of electrode islands 461.sub.1-N distributed along a
length of the spline 405. The electrode islands 461.sub.1-N may
include three or more electrodes 402 configured in a clique
412.sub.1. The cliques of electrodes may be used in various bi-pole
configurations to facilitate measurement of electrical
characteristics of tissue in contact with the electrodes. Each
clique is capable of measuring signals indicative of the unique
orientation specific electrical characteristics of the tissue in at
least two or more orientations. For example, clique 412.sub.1 in
the present embodiment includes four electrodes 402.sub.1-4. A
first bi-pole pair includes electrodes 402.sub.1,3 facilitating the
collection of tissue electrical characteristic data in an
orientation substantially parallel with the catheter's longitudinal
axis. A second bi-pole pair includes electrodes 402.sub.2,4
facilitating the collection of tissue electrical characteristic
data in an orientation substantially transverse to the catheter's
longitudinal axis. To facilitate collecting this electrical data,
these bi-pole electrode pairs may be independently addressable by
signal processing circuitry. The signal processing circuitry
analyzes the received signals from the electrodes in the clique to
determine orientation independent electrophysiology information of
the tissue in contact with the clique electrodes.
[0079] While the present embodiment depicts each of the electrodes
402.sub.1-4 in the clique 412.sub.1 positioned on an exterior
surface of the spline 405, to further detect contact tissue
electrical characteristics in a third direction, or z-direction
(e.g., normal to tissue), a fifth electrode in the clique may be
mounted to an interior surface of the spline 405. The fifth
electrode may be a non-contact electrode, and may be paired with at
least one of the electrodes 402.sub.1-4 on the exterior surface of
the spline 405 to determine the electrical characteristics of the
tissue in the z direction.
[0080] In various embodiments consistent with the present
disclosure, the splines and electrode islands may be formed from
flexible electronic circuit boards with each of the electrodes
coupled thereto and communicatively coupled to signal processing
circuitry via electrical traces that extend along interior or
exterior surfaces of the flexible printed circuit board. In some
specific embodiments, each of the splines may consist of a nitinol
strut. The flex circuit may be either bonded directly to the
nitinol, or, alternatively, the flex circuit may be directly bonded
to pebax tubing which houses the nitinol strut internally.
[0081] In some specific embodiments, the electrodes may be 0.8
millimeters in diameter with a total surface area of 0.5 mm.sup.2.
The electrodes in each clique may be various sizes and shapes. For
example, a smaller size electrode(s) (e.g., 0.8 mm in diameter) for
electrophysiology mapping, and larger size electrode(s) that may be
capable of both electrophysiology mapping and have a large enough
impedance to facilitate localization in an impedance or
hybrid-based catheter navigation system (e.g., MediGuide.TM.
System, and/or EnSite NavX system). In one particular embodiment,
the smaller electrophysiology mapping catheters may be coupled to
an external-facing surface of the splines for direct contact with
tissue, with larger, non-contact navigation electrodes coupled to
an internal-facing surface of the splines.
[0082] While it may be desirable in some embodiments to have equal
spacing between all of the electrodes in a clique, knowledge of the
relative spacing between each of the electrodes which form bi-pole
pairs is sufficient to accurately capture orientation-specific
electrical characteristic data of tissue in contact with the
electrodes. In some specific embodiments, edge-to-edge spacing for
one or more of the bi-pole pairs of electrodes may be between 2-2.5
millimeters. To simplify signal processing, consistent spacing
between all of the electrodes in a clique or across the entire
basket catheter may be desirable. In yet other specific
embodiments, center-to-center spacing of the electrodes in a clique
may be between 0.5-4 millimeters.
[0083] Various embodiments of the present disclosure are directed
to cliques of electrodes forming a 2.times.2 array, and a
triangular-shaped clique with electrodes positioned at each corner.
Any of these clique configurations are sufficient to determine
contacted tissue electrical characteristics in two or more
orientations. Some embodiments of the triangular-shaped clique may
form a right-triangle or an isosceles triangle. Some embodiments of
the isosceles triangle include a vertex angle between
30-140.degree.. More complex cliques may include five or more
electrodes to facilitate sampling electrical characteristics of a
tissue at relative orientations of less than 90.degree.. Such an
embodiment further reduces the electrophysiology mapping error
associated with the directionality of an electrical wavefront
traveling through the heart.
[0084] FIG. 5A is a plan view of a basket catheter 500 in an
expanded configuration, consistent with various embodiments of the
present disclosure. The basket is comprised of a plurality of
splines 503, 504, 505, 506 which are coupled to a catheter shaft
507 at a proximal end and to a distal cap or one another at a
distal end 544. While the present embodiment presents a basket
comprised of four splines 503, 504, 505, 506, basket catheters with
three or more splines are readily envisioned with the design
depending on an intended clinical application and desired
electrophysiology mapping granularity. To facilitate
expansion/contraction of the basket, a deployment member 560
extends along a longitudinal axis of the basket. The deployment
member in some embodiments may be a pull-wire, which extends
proximally to a catheter handle at a proximal end of the catheter
shaft 507. Actuation of the pull-wire causes expansion/contraction
of the basket.
[0085] In the present embodiment, each of the splines 503, 504,
505, 506 includes ribs 561.sub.1-N distributed about a length of
each spline. Each of the ribs extends transverse to a direction of
the mating spline. The splines and ribs facilitate distribution of
electrodes across inner and/or outer surfaces thereof. In various
embodiments, the splines and ribs are formed from flexible
electronic circuit boards, and/or have flexible electronic circuit
boards adhered to one or more surfaces of the splines and ribs.
Each of the electrodes may be communicatively and mechanically
coupled to the flexible circuit board via pads, with electrical
traces communicatively coupling the electrodes to signal processing
circuitry.
[0086] While the embodiment presented in FIGS. 5A-D depicts ribs
561.sub.1-N regularly distributed along the length of each spline
503, 504, 505, 506, other embodiments may include ribs 561.sub.1-N
unevenly distributed along the splines. For example, in pulmonary
vein electrophysiology mapping applications, only a distal portion
of the basket may be in contract with tissue proximal the pulmonary
veins. Accordingly, a distribution of ribs 561.sub.1-N may be
weighted toward a distal end 544 of the basket to facilitate
enhanced electrophysiology mapping granularity in proximity to the
pulmonary veins.
[0087] Various embodiments of the present disclosure are directed
to ribs 561.sub.1-N on each of the respective splines 503, 504,
505, 506, with the ribs 561.sub.1-N on adjacent splines being
longitudinally offset to facilitate interleaving when the basket is
being delivered via an introducer sheath in a contracted
configuration.
[0088] FIG. 5B is a plan view of the basket catheter 500 of FIG. 5A
in a contracted configuration, consistent with various embodiments
of the present disclosure. Small serpentine gaps 554 are located
between each of the adjacent splines 503-506. In the contracted
configuration of the basket catheter, a deployment member 560 (as
shown in FIG. 5A) may be extended distally to allow each of the
splines to be drawn in radially toward a longitudinal axis of the
catheter shaft 507.
[0089] As shown in FIG. 5B, ribs 561.sub.1-N on adjacent splines
503-506 are longitudinally offset to facilitate interleaving the
ribs to minimize collapsed basket catheter package size. To
facilitate the collapsed state of the splines 503-506, the relative
distance between catheter shaft 507 and distal end 544 is increased
via deployment member 560.
[0090] FIG. 5C is an enlarged, plan view of a portion of spline 505
of FIG. 5A, consistent with various embodiments of the present
disclosure. The enlarged, plan view further showing three of the
ribs 561.sub.1-3 distributed along a length of the spline 505. The
spline 505 and ribs 561.sub.1-3 may house a plurality of electrodes
for electrophysiology mapping of cardiovascular tissue, for
example. As shown in FIG. 5C, the plurality of electrodes 502 are
configured in three overlapping cliques 512.sub.1-3. Each clique of
electrodes may be used in various bi-pole configurations to
facilitate measurement of electrical characteristics of tissue in
contact with the electrodes. Each clique is capable of measuring
the directionally distinct electrical characteristics of the
contacted tissue in two or more orientations. For example, clique
512.sub.1 in the present embodiment includes five electrodes
502.sub.1-5. A first bi-pole pair may include, for example
electrodes 502.sub.1,3 facilitating the collection of tissue
electrical characteristic data in an orientation substantially
parallel with the catheter's longitudinal axis. A second bi-pole
pair includes electrodes 502.sub.2,4 facilitating the collection of
tissue electrical characteristic data in an orientation
substantially transverse to the catheter's longitudinal axis.
[0091] In some specific embodiments, some of the electrodes 502
within a clique 512 may be multi-purpose, while other electrodes
are single-purpose. For example, electrodes 502.sub.1,3 may
function as both navigation and electrophysiology mapping
electrodes, electrodes 502.sub.2,4 may function only as
electrophysiology mapping electrodes, and electrode 502.sub.5 may
function only as a navigation electrode. In various embodiments of
the present disclosure, the cliques form a two-dimensional shape
(e.g., triangle, square, hexagon, etc.).
[0092] While the present embodiment depicts each of the electrodes
502.sub.1-5 in the clique 512.sub.1 positioned on an exterior
surface of the spline 505, to further detect tissue electrical
characteristics in a third orientation (i.e., normal to tissue),
one or more electrodes in the clique may be mounted to an interior
surface of the spline 505. The fifth electrode may be a non-contact
electrode, and be paired with at least one of the electrodes
502.sub.1-5 on the exterior surface of the spline 505 to determine
the electrical characteristics of the contacted tissue in a normal
direction relative to a surface of the tissue. Moreover, as the
navigation electrodes do not necessarily need to be in contact with
tissue, the navigation-only electrodes may be placed on the
interior surface of the spline 505.
[0093] FIG. 5D is an enlarged, top view of a distal end 544 of the
basket catheter of FIG. 5A, consistent with various embodiments of
the present disclosure. FIG. 5D further shows the placement of
electrode cliques 512.sub.4-6 in proximity to the distal end 544 of
the basket catheter. This distal placement of electrodes may be
particularly advantageous in various applications (e.g.,
electrophysiology mapping of left atrium with specific focus on the
electrical signals emanating in and around the pulmonary vein).
[0094] FIG. 6A is a plan view of a basket catheter spline 600 and
FIG. 6B is an enlarged, plan view of a portion of the basket
catheter spline 600 of FIG. 6A, consistent with various embodiments
of the present disclosure. The basket catheter spline 600 includes
a plurality of electrodes 602.sub.1-N which may be associated with
one or more cliques 612. As shown in FIG. 6B, electrodes
602.sub.1,3-4 are configured in an electrode clique 612.sub.1. The
electrodes in the clique 612.sub.1 may be independently addressable
by signal processing circuitry to detect electrical characteristics
of tissue in contact with the electrodes via one or more electrode
bi-pole pairs in the clique which allow for the detection of
electrical signal variation associated with the directional flow of
electrical signals through a cardiac muscle, for example. In the
present embodiment, the electrode clique forms an isosceles
triangles with a vertex angle of approximately 30.degree..
[0095] As shown in FIG. 6B, a number of the electrodes, electrodes
602.sub.1,3 for example, are not positioned along a centerline of
the spline 600. Instead, the electrodes 602.sub.1,3 are positioned
offset from the centerline of the spline 600 on pads to form the
desired triangular clique 612.sub.1 arrangement. In such an
embodiment, an adjacent spline may have its electrodes
longitudinally offset to facilitate interleaving of the respective
pads extruding from each spline when contracting the basket
catheter.
[0096] FIG. 7A is a plan view of a basket catheter spline 700 and
FIG. 7B is an enlarged, plan view of a portion of the basket
catheter spline 700 of FIG. 7A, consistent with various embodiments
of the present disclosure. The basket catheter spline 700 includes
a plurality of electrodes 702.sub.1-N which may be associated with
one or more cliques 712. As shown in FIG. 7B, electrodes
702.sub.1-3 are configured in an electrode clique 712.sub.1. In the
present embodiment, the electrode clique forms an isosceles
triangle with a vertex angle of approximately 110.degree..
[0097] As shown in FIG. 7B, each of the electrodes 702 are
positioned offset from the centerline of the spline 700 on pads to
form the triangular clique 712 arrangement. In such an embodiment,
an adjacent spline on the basket catheter may have its electrodes
longitudinally offset to facilitate interleaving of the respective
pads extruding from each spline when contracting the basket
catheter.
[0098] FIG. 8A is a plan view of two interleaved basket catheter
splines 800 and FIG. 8B is an enlarged, plan view of a portion of
the two interleaved basket catheter splines 800 of FIG. 8A,
consistent with various embodiments of the present disclosure. The
two splines 803 and 804 include a plurality of electrodes
802.sub.1-N distributed along a length of the splines. In the
present embodiment, each of the splines 803 and 804 have a
"saw-tooth" shape that facilitates seating adjacent splines into
complimentary features thereof when the basket catheter is
contracted. The saw-tooth shape further facilitates triangular
cliques 812.sub.1 of electrodes 802.sub.1-3, which in some
embodiments form an isosceles triangle with a vertex angle of
approximately 110.degree..
[0099] In some embodiments consistent with the present disclosure,
the cliques of electrodes remain in a triangular-shape even when
the basket catheter is in a collapsed configuration. In various
embodiments, the triangular-shaped cliques of electrodes are formed
from immediately adjacent electrodes.
[0100] While various embodiments of high-density electrode
catheters are disclosed herein, the teachings of the present
disclosure may be readily applied to various other catheter
embodiments as disclosed, for example, in the following patents and
patent applications which are hereby incorporated by reference:
U.S. provisional application No. 61/753,429, filed 16 Jan. 2013;
U.S. provisional application No. 60/939,799, filed 23 May 2007;
U.S. application Ser. No. 11/853,759 filed 11 Sep. 2007, now U.S.
Pat. No. 8,187,267, issued 29 May 2012; U.S. provisional
application No. 60/947,791, filed 3 Jul. 2007; U.S. application
Ser. No. 12/167,736, filed 3 Jul. 2008, now U.S. Pat. No.
8,206,404, issued 26 Jun. 2012; U.S. application Ser. No.
12/667,338, filed 20 Jan. 2011 (371 date), published as U.S. patent
application publication no. US 2011/0118582 A1; U.S. application
Ser. No. 12/651,074, filed 31 Dec. 2009, published as U.S. patent
application publication no. US 2010/0152731 A1; U.S. application
Ser. No. 12/436,977, filed 7 May 2009, published as U.S. patent
application publication no. US 2010/0286684 A1; U.S. application
Ser. No. 12/723,110, filed 12 Mar. 2010, published as U.S. patent
application publication no. US 2010/0174177 A1; U.S. provisional
application No. 61/355,242, filed 16 Jun. 2010; U.S. application
Ser. No. 12/982,715, filed 30 Dec. 2010, published as U.S. patent
application publication no. US 2011/0288392 A1; U.S. application
Ser. No. 13/159,446, filed 14 Jun. 2011, published as U.S. patent
application publication no. US 2011/0313417 A1; international
application no. PCT/US2011/040629, filed 16 Jun. 2011, published as
international publication no. WO 2011/159861 A2; U.S. application
Ser. No. 13/162,392, filed 16 Jun. 2011, published as U.S. patent
application publication no. US 2012/0010490 A1; U.S. application
Ser. No. 13/704,619, filed 16 Dec. 2012, which is a national phase
of international patent application no. PCT/US2011/040781, filed 16
Jun. 2011, published as international publication no. WO
2011/159955 A1.
[0101] While the various embodiments presented in FIGS. 1-8 are
amenable to the application of spot electrodes coupled to a
flexible electronic circuit, where the flexible electronic circuit
may also (partially) comprise the splines, arms, and shaft of the
various catheters, yet other embodiments may be directed to the use
of ring electrodes crimped or swaged onto splines, arms, and shafts
comprising well-known materials in the art. The ring electrodes
being electrically coupled to signal processing circuitry using
lead wires. The ring electrodes being positioned along the splines,
arms, and shafts of the catheters to form cliques of electrodes
with equal and known spacing therebetween. In yet other
embodiments, ring electrodes may be swaged or crimped onto a
flexible circuit board comprising at least part of the splines,
arms, and/or shaft of the various catheters disclosed herein.
[0102] Although several embodiments have been described above with
a certain degree of particularity, those skilled in the art could
make numerous alterations to the disclosed embodiments without
departing from the spirit of the present disclosure. It is intended
that all matter contained in the above description or shown in the
accompanying drawings shall be interpreted as illustrative only and
not limiting. Changes in detail or structure may be made without
departing from the present teachings. The foregoing description and
following claims are intended to cover all such modifications and
variations.
[0103] Various embodiments are described herein of various
apparatuses, systems, and methods. Numerous specific details are
set forth to provide a thorough understanding of the overall
structure, function, manufacture, and use of the embodiments as
described in the specification and illustrated in the accompanying
drawings. It will be understood by those skilled in the art,
however, that the embodiments may be practiced without such
specific details. In other instances, well-known operations,
components, and elements have not been described in detail so as
not to obscure the embodiments described in the specification.
Those of ordinary skill in the art will understand that the
embodiments described and illustrated herein are non-limiting
examples, and thus it can be appreciated that the specific
structural and functional details disclosed herein may be
representative and do not necessarily limit the scope of the
embodiments, the scope of which is defined solely by the appended
claims.
[0104] Reference throughout the specification to "various
embodiments," "some embodiments," "one embodiment," "an
embodiment," or the like, means that a particular feature,
structure, or characteristic described in connection with the
embodiment is included in at least one embodiment. Thus,
appearances of the phrases "in various embodiments," "in some
embodiments," "in one embodiment," "in an embodiment," or the like,
in places throughout the specification are not necessarily all
referring to the same embodiment. Furthermore, the particular
features, structures, or characteristics may be combined in any
suitable manner in one or more embodiments. Thus, the particular
features, structures, or characteristics illustrated or described
in connection with one embodiment may be combined, in whole or in
part, with the features structures, or characteristics of one or
more other embodiments without limitation.
[0105] It will be appreciated that the terms "proximal" and
"distal" may be used throughout the specification with reference to
a clinician manipulating one end of an instrument used to treat a
patient. The term "proximal" refers to the portion of the
instrument closest to the clinician and the term "distal" refers to
the portion located furthest from the clinician. It will be further
appreciated that for conciseness and clarity, spatial terms such as
"vertical," "horizontal," "up," and "down" may be used herein with
respect to the illustrated embodiments. However, surgical
instruments may be used in many orientations and positions, and
these terms are not intended to be limiting and absolute.
[0106] Any patent, publication, or other disclosure material, in
whole or in part, that is said to be incorporated by reference
herein is incorporated herein only to the extent that the
incorporated materials does not conflict with existing definitions,
statements, or other disclosure material set forth in this
disclosure. As such, and to the extent necessary, the disclosure as
explicitly set forth herein supersedes any conflicting material
incorporated herein by reference. Any material, or portion thereof,
that is said to be incorporated by reference herein, but which
conflicts with existing definitions, statements, or other
disclosure material set forth herein will only be incorporated to
the extent that no conflict arises between that incorporated
material and the existing disclosure material.
* * * * *