U.S. patent application number 11/191053 was filed with the patent office on 2005-11-24 for infusion device and method.
This patent application is currently assigned to Boston Scientific Scimed, Inc.. Invention is credited to Crank, Justin, Larson, Scott, Mickley, Timothy J..
Application Number | 20050261667 11/191053 |
Document ID | / |
Family ID | 25003883 |
Filed Date | 2005-11-24 |
United States Patent
Application |
20050261667 |
Kind Code |
A1 |
Crank, Justin ; et
al. |
November 24, 2005 |
Infusion device and method
Abstract
Devices and methods for performing improved percutaneous
myocardial revascularization (PMR) procedures. One device includes
a preassembled PMR drug delivery catheter and a drug neutralizing
vial. The vial assembly allows prepping the PMR catheter by
flushing drug through distal needle, and into a vial cavity where
the drug is neutralized by a neutralizing agent. One set of devices
includes needles having protrusions secured to the distal regions
of drug delivery tubes. One needle has outward protruding barbs
engaging the inner tube wall while another needle has outward
threads which can screw into the tube inner wall. Radiopaque marker
bands are also included in the present invention which are
asymmetrically distributed on the catheter shaft, allowing a
treating physician to determine under fluoroscopy whether the
catheter distal region is pointed away or toward the treating
physician, as well as determining whether the catheter distal
region is rotated toward or away from the treating physician. PMR
devices include catheters having dual injection needles, for both
injecting a drug into the heart wall and a radiopaque contrast
media to mark the already treated sites. One PMR injection device
has multiple stops for allowing controlled, variable needle depth
penetration with a single distal needle tip.
Inventors: |
Crank, Justin; (Minneapolis,
MN) ; Larson, Scott; (St. Louis Park, MN) ;
Mickley, Timothy J.; (Elk River, MN) |
Correspondence
Address: |
KENYON & KENYON
1500 K STREET NW
SUITE 700
WASHINGTON
DC
20005
US
|
Assignee: |
Boston Scientific Scimed,
Inc.
|
Family ID: |
25003883 |
Appl. No.: |
11/191053 |
Filed: |
July 28, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11191053 |
Jul 28, 2005 |
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10621378 |
Jul 18, 2003 |
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6939322 |
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10621378 |
Jul 18, 2003 |
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09747157 |
Dec 21, 2000 |
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6616626 |
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Current U.S.
Class: |
604/529 |
Current CPC
Class: |
A61M 25/0068 20130101;
A61J 1/1406 20130101; A61M 25/0074 20130101; A61M 2025/0085
20130101; A61M 2025/0081 20130101; A61M 2210/125 20130101; A61M
25/0084 20130101; A61M 2025/0086 20130101; A61M 25/0108 20130101;
A61M 2205/19 20130101; A61M 2025/0008 20130101; A61M 5/46 20130101;
A61M 25/0662 20130101; A61M 2025/0091 20130101 |
Class at
Publication: |
604/529 |
International
Class: |
A61M 025/098 |
Claims
What is claimed is:
1. A catheter comprising: an elongate shaft having a central
longitudinal axis, a radial dimension extending outward from said
central axis, and a distal region, wherein a plane bisecting said
shaft through said longitudinal axis defines a shaft first portion
and a shaft second portion opposite said shaft first portion; and a
radiopaque marker disposed in said shaft distal region, wherein
said radiopaque marker is asymmetric about said bisecting plane,
such that said catheter distal portion appears differently under
fluoroscopy when viewed from an angle less than ninety degrees
(90.degree.) to said plane than when viewed from an angle greater
than ninety degrees (90.degree.) to said plane.
2. A catheter as in claim 1, wherein said marker is asymmetric with
respect to a transverse bisecting plane through said shaft and
marker.
3. A catheter as in claim 1, wherein said marker includes more than
one region, and said regions are contiguous with each other.
4. A catheter as in claim 1, wherein said marker includes a first
portion transverse to said central longitudinal axis and a second
portion parallel to said longitudinal axis.
5. A catheter as in claim 1, wherein said marker includes more than
one region, and said regions are not all contiguous with each
other.
6. A catheter as in claim 1, wherein said radiopaque marker
includes a first arcuate portion disposed about said shaft and a
second linear portion disposed along said shaft and substantially
parallel to said shaft longitudinal axis.
7. A catheter as in claim 6, wherein said first arcuate portion
includes an annular portion about said shaft and contiguous with
said second marker portion.
8. A catheter as in claim 1, wherein said marker includes a first
portion extending along said shaft length parallel to said central
longitudinal axis and a second portion extending transversely to
said shaft central axis.
9. A catheter as in claim 8, wherein said shaft has a length and a
circumference, wherein said marker first portion includes an
arcuate shell extending along said shaft length in an annular
fashion around less than all of said shaft length in an annular
fashion around less than all of said shaft circumference, wherein
said second marker portion is an annular band extending
transversely to said central axis.
10. A catheter as in claim 1, wherein said first marker portion
includes a first arcuate shell on one side of said bisection plane,
wherein said second marker portion includes a second arcuate shell
disposed on the other side of said bisection plane relative to said
first arcuate shell, wherein said first and second arcuate shells
are disposed over different lengths on said shaft.
11. A catheter as in claim 10, wherein said catheter shaft has a
bend, and said marker is disposed proximal of said bend.
12. A catheter as in claim 10, wherein said arcuate shells are
substantially annular.
Description
RELATED CASES
[0001] The present application is a continuation of U.S.
application Ser. No. 10/621,378, which was filed on Jul. 18, 2003,
was entitled Infusion Devices and Method and is now U.S. Pat. No.
______. The '378 application is itself a continuation of U.S. Pat.
No. 6,616,626, which was filed on Dec. 21, 2000 and shares the same
name.
FIELD OF THE INVENTION
[0002] The present invention is related generally to medical
devices. More specifically, the present invention is related to
devices and methods associated with delivery of genes or
therapeutic substances.
BACKGROUND OF THE INVENTION
[0003] A number of techniques are available for treating heart
disease and diseases of other organs percutaneously. Examples of
such techniques include delivery of genes and therapeutic
substances, including the delivery of genes and therapeutic
substances for percutaneous myocardial revascularization (PMR).
This procedure is performed to increase blood perfusion through the
myocardium of a patient. For example, in some patients, the number
of lesions in coronary vessels is so great or the location so
remote in the patient vasculature that restoring blood flow to the
heart muscle is difficult. Percutaneous myocardial
revascularization (PMR) has been developed as an alternative to
techniques which are directed at bypassing or removing lesions. PMR
is performed by boring holes directly into the myocardium of the
heart. Positive results have been demonstrated in some human
patients receiving PMR treatments. These results are believed to be
caused in part by blood flowing from within a heart chamber through
patent holes formed by PMR to the myocardial tissue. Suitable PMR
holes have been proposed to be burned by laser, cut by mechanical
means, and burned by radio frequency devices. Increased blood flow
to the myocardium is also believed to be caused in part by the
healing response to wound formation, specifically, the formation of
new blood vessels in response to the newly created wound.
[0004] Several aspects of PMR procedures could be improved upon.
One area for improvement is in the preparation of PMR injection
catheters for use by the treating physician. In particular, at
present, the PMR device maybe flushed with a drug to prime the
distal needle by flushing the drug through the needle and into a
container. This preparation can be awkward and may leave a
container of biologically active material which may require further
processing. Another aspect which may be farther optimized lies in
the attachment of the needle to the distal region of the PMR
catheter tube. In particular, forces may act upon the needle during
both the advancement and retraction of the needle within the heart
wall, urging the needle undesirably both into and out of the tube.
Improved methods of securing the needle to the tube would be
desirable.
[0005] During a PMR treatment, a physician may be attempting to
treat a three-dimensional space using a catheter having a distal
bend. In particular, the physician may be attempting to treat the
heart chamber side, anterior, and posterior wall regions. This may
presently be difficult to visualize under fluoroscopy as current
marking systems for shafts may make interpretation of the catheter
distal region orientation somewhat ambiguous. The heart chamber
wall thickness can vary depending on the chamber and wall region
being treated. In particular, the left ventricle wall is thinner in
the posterior region relative to the anterior region. Improved
devices for variable depth, yet controlled penetration of the heart
walls, would be advantageous. As multiple sites of the heart
chamber wall are penetrated, a system for tracking the treated
versus untreated regions would also be desirable.
SUMMARY OF THE INVENTION
[0006] The present invention includes improved devices and methods
for performing PMR procedures. One device allows for improved
preparation of PMR catheters used to inject a drug or therapeutic
substance into the heart wall. One such device includes a PMR
device distal region or hood disposed within the neck of a vial for
receiving the drug. The vial can be used to receive the drug while
the drug is being flushed through the PMR device and needle to
prepare the PMR device for use. One vial has a neck and shoulder
region for receiving and retaining the distal region of a PMR
injection device. A no-leak gasket defines one wall of an inner
cavity within one such vial.
[0007] The vial is preferably formed of a transparent or
translucent material for observing the injection of the drug into
the vial. In one embodiment, the vial cavity includes a
drug-neutralizing agent. The agent allows the drug to be
neutralized after receiving the drug. A neutralizing agent can
provide improved safety, should the integrity of the vial be
breached. The drug-neutralizing vial allows a biologically active
drug to be flushed through the catheter with the vial being
disposed of in a normal waste stream such as a wastebasket, rather
than requiring special handling.
[0008] One set of devices provides improved needle attachment to
drug delivery tubes. One improved drug delivery tube has an outer
tube defining a lumen therein. A needle may be disposed within the
distal end of the tube. The needle can have a distal, sharp tube
region for insertion into the heart wall, as a well as a wider,
more proximal region having outward protrusions for engaging or
biting into the drug delivery tube inner wall. One device has a
wide flange for abutting the drug delivery tube distal end, thereby
limiting the proximal travel of the needle into the drug delivery
tube lumen. One drug delivery tube also has a bonding hole which
can be used to inject an adhesive to further secure the needle
within the drug delivery tube distal region. The improved securing
of the needle to the drug delivery tube can act to prevent the
needle from being distally pulled from the tube.
[0009] During insertion of the needle into the heart wall, forces
can act to urge the needle into the tube. Upon retraction of the
needle from the heart wall, forces may act to pull the needle
distally from the tube. Both the outward protrusions, the flange,
and the added adhesive can act to better secure the needle to the
drug delivery tube. One embodiment includes outward barbs biting
into the drug delivery tube, while another embodiment uses a series
of helically disposed screw threads to engage the tube wall. A
preferred embodiment uses outward protruding elements which engage
the inner wall, while another embodiment uses inwardly protruding
elements engaging the outer wall of the tube distal region.
[0010] Another aspect of the invention provides improved
visualization of the catheter shaft orientation under fluoroscopy.
One embodiment utilizes asymmetrically disposed radiopaque markers
on the shaft distal region to enable the treating physician to
determine whether the catheter distal region is pointed at right
angles to the treating physician or is pointed toward or away from
the treating physician. One embodiment has the radiopaque marker
being asymmetrically distributed with respect to a plane bisecting
a longitudinal axis of the catheter tube distal region. Another
embodiment further includes the radiopaque marker being
asymmetrically distributed with respect to length over the catheter
distal region. One marker includes an annular ring portion and a
straight leg portion lying along the length of one side of the
tube. Yet another embodiment includes an annular shell or ring
portion and an annular arc leg portion extending along a length
from the annular shell or ring portion. The radiopaque markers may
be disposed on either the proximal or the distal side of any bend
in the catheter shaft. A preferred use of the radiopaque marker
band is on a guide catheter used to guide a PMR therapeutic tip to
the heart wall.
[0011] In yet another aspect of the invention, radiopaque marker
segments are asymmetrically distributed such that the rotation of
the tube relative to the treating physician may be determined under
fluoroscopy. One embodiment uses opposing annular shells on
opposing sides of a tube where the annular shells are shifted
longitudinally relative to each other. The asymmetrically disposed
shells are thus asymmetric both with respect to a plane bisecting a
longitudinal central access and with respect to a plane
transversely bisecting a catheter shaft.
[0012] In still another aspect of the invention, marker bands are
provided a distance apart which approximates the desired
inter-treatment site spacing along the heart wall. A method can be
performed using this aspect of the invention, whereby a therapeutic
substance is delivered at treatment sites which are observed under
fluoroscopy to be spaced apart approximately the distance between
marker bands. Any distortion or magnification of the distances
between marker bands will approximately be matched by distortions
between treatment sites.
[0013] The present invention also includes a PMR device for
allowing precise, variable depth needle penetration of the heart
wall. One device includes at least one inner stop affixed to a
rotatable inner needle. The device also can have one or more stops
disposed inwardly from an outer tube, the outer tube having the
inner needle rotatably disposed within. The inner needle can be
longitudinally advanced until the inner stop abuts an outer stop,
thereby inhibiting further distal movement of the inner needle. If
greater penetration is desired, the inner shaft can be rotated,
thereby swinging the inner stop clear of the first encountered
outer stop, allowing the inner stop to proceed further distally
until a subsequent outer stop is encountered. This aspect of the
invention allows a single device to be used, yet provides multiple,
preset, precise penetration depths. This may be of particular use
where the thickness of the heart wall varies over different regions
of the heart chamber wall.
[0014] Yet another aspect of the invention provides for injection
of drug and contrast media into the heart wall. Injection of
contrast media near the injection site of a drug allows the
treating physician to visualize under fluoroscopy which areas of
the heart wall have been treated and which have not yet been
treated. One device provides a contrast media injection needle
disposed side-by-side with a drug delivery needle. One embodiment
allows the two side-by-side needles to be retracted and advanced
together. The needles can be distally straight, arcuate, or one
arcuate and one straight. Another embodiment provides a drug and
contrast media injection device having a pair of needles, one being
coaxially disposed within the other. The innermost needle can be
used to inject drug deep into the heart tissue, while the more
outer, coaxially disposed needle may be used to inject contrast
media to the heart wall, thereby marking the site of treatment. One
embodiment utilizes a sharp, cutting end to inject contrast media.
Another embodiment uses a less sharp, less cutting end, for
injecting a contrast media into the heart wall tissue using
pressure, rather than cutting.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a fragmentary, side, cutaway view of a myocardial
revascularization preparation system including a drug neutralizing
vial and a myocardial revascularization drug delivery catheter in
the process of being prepared for use by flushing a drug through
the injection needle into the drug-neutralizing vial;
[0016] FIG. 2 is a fragmentary, longitudinal, cross-sectional view
of a drug delivery catheter distal portion having a needle disposed
within a tube, the needle having barbs for engaging the tube inner
wall to improve needle retention;
[0017] FIG. 3 is a fragmentary, longitudinal, cross-sectional view
of a drug delivery catheter distal portion having a needle disposed
within a tube, the needle having threads for engaging the tube
inner wall to improve needle retention;
[0018] FIGS. 4A-4C are perspective views of a prior art catheter
shaft having an annular radiopaque band;
[0019] FIGS. 5A-5C are perspective views of a catheter shaft having
an asymmetric radiopaque marker;
[0020] FIGS. 5D-5E are transverse, cross-sectional views taken
through the catheter of FIGS. 5A-5C;
[0021] FIGS. 6A-6C are perspective views of a catheter having an
asymmetric radiopaque marker;
[0022] FIGS. 6D-6E are transverse, cross-sectional views taken
through the catheter of FIGS. 6A-6C;
[0023] FIG. 7 is a perspective view of a catheter shaft having an
asymmetric, radiopaque marker disposed proximal of a bend;
[0024] FIGS. 8A-8H are plan views of a catheter shaft having an
asymmetric radiopaque marker in varying degrees of rotation;
[0025] FIGS. 9A and 9B are perspective views of a guide catheter
shaft including radiopaque marker bands having an inter-band
distance corresponding to a desired myocardial revascularization
treatment site spacing;
[0026] FIG. 10 is a fragmentary, longitudinal cross-sectional view
of a PMR catheter having multiple stops for controlling needle
penetration;
[0027] FIGS. 11A-11C are fragmentary, longitudinal cross-sectional
views of a PMR catheter having side-by-side needles for injection
of a drug and a radiopaque fluid; and
[0028] FIGS. 12A-12B are fragmentary, longitudinal cross-sectional
views of PMR devices having coaxially disposed drug and dye
delivery lumens.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0029] FIG. 1 illustrates a myocardial revascularization drug
delivery preparation assembly 30 including a drug receiving vial 32
and a drug delivery catheter 42 inserted into vial 32. Drug
delivery catheter 42 includes a tube 44 having a lumen 46
therethrough. Catheter 42 includes a distal portion 54 having an
injection device or needle 50 in fluid communication with lumen 46.
Catheter 42 further includes a distal hood 48, illustrated in an
expanded state. Drug injection needle 50 is illustrated penetrating
through a self-sealing, no-leak gasket 40. Gasket 40 can be
disposed within vial 32 in an annular seat 52, as shown.
[0030] Drug receiving vial 32 includes a wall 38, which is
preferably formed of a transparent or translucent material,
allowing both an expelled drug and catheter needle to be viewed
through the vial wall. Vial 32 includes a cavity 34 having a
drug-neutralizing agent 36 disposed within cavity 34. Vial 32
includes a neck region 58 for receiving catheter distal portion 54.
In one embodiment, vial 32 further includes a shoulder or contour
region 56 for engaging catheter distal hood 48. In some
embodiments, vial shoulder 56 and catheter hood 48 are
cooperatively sized such that shoulder 56 engages hood 48 even when
hood 48 is in a non-expanded state. Hood 48 is preferably
sufficiently compliant so as to allow retraction of hood 48 through
vial neck region 58 after preparing the catheter. Vial shoulder 56
can also flex to contain hood 48.
[0031] In use, drug delivery catheter preparing system 30 can be
provided substantially as illustrated in FIG. 1. Catheter 42 can be
provided either separate from, or already engaged within, vial neck
region 58. When catheter 42 is to be prepared, catheter 42 distal
portion 54 can be inserted into vial neck region 58, if not already
so disposed. Catheter 42 can be further advanced, forcing needle 50
through gasket 40, and into cavity 34. With needle 50 inserted
through gasket 40, the drug to be delivered can be flushed through
needle 50 into cavity 34, preferably mixing with a neutralizing
agent. In this way, the drug to be delivered can be loaded into
catheter 42, preparing the catheter for use. The excess drug can be
contained within cavity 34, which may be desirable where the drug
is potentially harmful or must be isolated for other reasons.
Catheter 42 can be retracted from vial 32 when needed. Gasket 40 is
preferably formed of a self-sealing material, such that a seal is
re-formed after needle 50 is withdrawn. In embodiments having a
drug-neutralizing agent, the contents of the vial will be harmless,
even if the vial integrity is compromised. After preparing, vial 32
can be disposed of in a proper manner. In some embodiments, vial
32, containing either a harmless or a neutralized drug, may be
disposed of in a wastebasket, with no special handling
required.
[0032] Catheter 42 can be used to inject various drugs or other
therapeutic substances into the myocardium. Examples of therapeutic
substances include small molecular drugs, proteins, genes and cells
which could promote angiogenesis, protect tissues (i.e., cardiac
protection), or promote tissue regeneration. Vascular Endothelial
Growth Factor (VEGF) and Fibroblast Growth Factors (FGFs) are
believed suitable for use with the present invention. Carriers for
the therapeutic agents of the present invention can include
polymers, angiopoietins, biodegradable and biostable hydrogels, and
dissoluble polymers. Adhesives suitable for binding the present
invention include fibrin glues and cyanoacrylates which may also be
included with the therapeutic substance to improve the desired
response. Drug injection catheters referred to in the remainder of
the present patent application, and drugs similarly referenced, may
include the injection and use of the aforementioned therapeutic
substances.
[0033] Catheter 42, as well as subsequently referenced drug
injection catheters or myocardial revascularization catheters, can
include catheters such as those described in co-pending U.S. patent
application Ser. No. 09/271,045, filed Mar. 17, 1999, entitled
TRANSMYOCARDIAL REVASCULARIZATION CATHETER AND ASSEMBLY; and U.S.
patent application Ser. No. 09/184,220, filed Nov. 2, 1998,
entitled PERCUTANEOUS MYOCARDIAL REVASCULARIZATION GROWTH FACTOR
MEDIUMS AND METHOD, herein incorporated by reference. In
particular, guide catheters described according to the present
invention may be used to guide these previously referenced devices,
and others, to target sites in the myocardium.
[0034] FIG. 2 illustrates the distal portion of a drug delivery
catheter 60 which, in a preferred use, can be used for a procedure
such as myocardial revascularization. Drug delivery catheter 60
includes a tube 62 having a wall 64 defining a drug delivery lumen
66 within. Catheter 60 has a distal region 68, terminating in a
distal end 76. Disposed within catheter tube 62 is a drug delivery
needle 78, including generally a wider, proximal portion 80, and a
narrower, distal portion 82. Distal portion 82 includes an elongate
tube 83 terminating in a sharp end 84. Needle wide proximal portion
80, in the embodiment illustrated, includes a plurality of wider
protrusions 88 spaced apart from each other by a plurality of
narrower regions 90. Protrusions 88, in a preferred embodiment,
include sharp tips or barbs 86 for engaging and gripping tube wall
64.
[0035] As can be seen in FIG. 2, outward protrusions or barbs 86
may form a plurality of deformations 69 where the barbs dig into
tube wall 64. In a preferred embodiment, barbs 86 have at least a
slight inclination toward the distal direction, such that
retraction of needle 78 from tube 62 is more difficult than
insertion of needle 78 into tube 62. In a preferred embodiment,
drug delivery catheter 60 includes a distal flange 72 which can
serve to limit travel of needle 78 into drug lumen 66. In the
embodiment illustrated, flange 72 abuts tube distal end 76 and has
a hole 74 therethrough for receiving needle distal tube portion 83.
In one embodiment, tube 62 includes a bonding hole 70 through tube
wall 64 for receiving adhesive. Adhesive can be injected through
hole 70 for improving the adherence of needle wide portion 80 to
tube distal region 68.
[0036] In one use, drug delivery catheter 60 can be advanced
through the vasculature and into a heart chamber wall. After
injection of a drug through drug lumen 66, drug delivery catheter
60 can be retracted, thereby retracting needle distal end 84. In a
situation where the heart wall grips needle distal tube portion 83,
barbs or protrusions 86 can serve to resist the distally directed
force attempting to retain needle 78.
[0037] Another drug delivery catheter 100 is illustrated in FIG. 3,
having a needle 114 disposed within a tube 102. Tube 102 includes a
tube wall 104 having an inner surface 108 and an outer surface 107.
Tube 102 includes a distal region 110, a distal end 112, and a
lumen 106 disposed therethrough. Needle 114 includes a distal tip
region 116 ending distally in a sharp distal end 118. Needle 114
also includes a proximal needle portion 118 including a plurality
of threads 120 which are spaced apart and have narrower regions 121
disposed between threads 120. Needle 114 includes a needle lumen
124 extending through needle 114 and having a proximal throat
region 126. Throat 126 can improve the flow characteristics of
fluid through the needle. Needle threads 120 may be seen to engage
or bite into tube wall 104. In the embodiment illustrated, threads
120 are disposed on the outside of needle 114, and engage inner
surface 108 of tube wall 104. In another embodiment, not requiring
illustration, the proximal portion of the needle extends over tube
104. In this embodiment, threads are disposed inward within the
needle lumen and engage tube outer surface 107, rather than the
inner surface. Needle 114 can be secured to tube 102 by advancing
needle 114 into tube lumen 106 and rotating 114, thereby screwing
needle 114 into tube lumen 106. Threads 120 thus secure needle 114
to tube 102 and resist the distally directed forces attempting to
urge needle 114 out of tube 102.
[0038] FIGS. 4A through 4C illustrate a prior art catheter shaft
130 having a bend 134 and extending to a distal end 132. Catheter
shaft 130 has an annular band 136 which includes a radiopaque
material. FIG. 4A is a side view, viewing catheter shaft 130 from
an angle of about ninety degrees (90.degree.) away from a
straight-on end view looking directly along the central
longitudinal axis. FIG. 4B illustrates catheter 130 viewed from an
angle of less than ninety degrees (90.degree.) off the center
longitudinal axis. FIG. 4B illustrates catheter shaft 130 where
distal end 132 is pointed more toward the viewer than away. FIG. 4C
illustrates catheter shaft 130 being pointed more away from than
toward the viewer. FIGS. 4B and 4C illustrate that annular
radiopaque band 136 looks somewhat elliptical, and looks about the
same, whether viewed from the front or the back. Annular band 136
thus looks the same when catheter shaft distal end 132 is pointed
toward or away from the viewer. Annular radiopaque band 136 gives
no indication under fluoroscopy of the direction the catheter shaft
distal end is pointed. This is a less than optimal attribute of
annular radiopaque band 136, when used in an application such as
myocardial revascularization, where the catheter shaft may be
rotated and translated in all directions.
[0039] FIGS. 5A through 5E illustrate a catheter shaft 140 having
an asymmetric radiopaque marker. Catheter shaft 140 includes a bend
141 disposed proximal of a distal end 142. Catheter 140 includes an
asymmetric radiopaque marker 144 including a first, annular or ring
portion 146 extending radially about the catheter and disposed
transversely to the catheter longitudinal axis, and a second,
straight portion 148, extending along one side of shaft 140 toward
distal end 142. FIG. 5A illustrates a side view of catheter shaft
140. The view of FIG. 5A is taken from about ninety degrees
(90.degree.) away from a straight-on end view, a view which would
look directly along the central longitudinal axis. FIG. 5B
illustrates a view of catheter shaft 140 with shaft distal end 142
pointed more toward the viewer than away. FIG. 5C illustrates
catheter shaft 140 having distal end 142 pointed more away from the
viewer than toward the viewer. As can be seen from inspection of
FIGS. 5B and 5C, marker 144 appears differently when the catheter
distal end is pointed away from the viewer compared to pointing
toward the viewer. The asymmetric marker band 146 thus provides an
indication under fluoroscopy of whether the catheter is pointed
away from, or toward the viewer.
[0040] FIG. 5D illustrates the asymmetric nature of radiopaque
marker 144. FIG. SD, taken through annular ring portion 146, shows
a more proximal slice through catheter shaft 140. FIG. 5E, taken
through a more distal portion of catheter 140, illustrates marker
144 having straight leg portion 148 only on one side. It may be
seen from FIGS. 5A through 5E that a plane bisecting the central
longitudinal axis of catheter shaft 140, will have differing,
asymmetrical portions of radiopaque marker on either side of the
bisecting plane. In particular, the markers on either side of the
bisecting plane are not mirror images of each other. It may also be
seen that marker 144, when compared proximal end to distal end, is
asymmetric along its length. In particular, radiopaque marker 144
does not have a distal portion which is a mirror image of its more
proximal portion.
[0041] FIG. 6A illustrates a catheter 160 having a radiopaque
marker 164 which is asymmetric and includes a first, annular arc
shell portion 166, and a second, annular ring portion 168. In FIG.
6A, it may be seen that a plane bisecting the central longitudinal
axis of catheter 160 would have an asymmetry with respect to the
marker about the bisecting plane. In particular, the right and left
halves of catheter 160 are not mirror images of each other. In FIG.
6A, catheter distal end 160 is pointed directly at the viewer. In
FIG. 6B, catheter 160 is directed such that catheter distal end 162
is pointed ninety degrees (90.degree.) away from the viewer,
directly to the side. In FIG. 6C, catheter 160 is pointed one
hundred eighty degrees (180.degree.) away from the viewer, toward
the back. Comparison of FIGS. 6A through 6C illustrates that marker
164 appears differently depending whether catheter distal end 162
is pointed toward the viewer, to the side of the viewer, or away
from the viewer. FIG. 6D shows a transverse cross-section taken
through radiopaque annular shell 166. Annular arc shell 166 extends
along the length of the catheter and substantially parallel to the
central longitudinal axis, similar in some respects to straight
segment 140 of FIGS. 5A through 5E, but wider. FIG. 6E shows a
transverse cross-section taken through marker 164 through annular
ring 168. The asymmetry about the bisecting plane may be seen in
FIGS. 6D and 6E, as well. Radiopaque marker 164 may also be seen to
be asymmetric about a transverse bisecting plane. In particular,
the top half of marker 164 in FIG. 6A is not the mirror image of a
bottom half of marker 164 in FIG. 6A.
[0042] In comparing FIGS. 5A through 5C and 6A through 6C, it may
be seen that both embodiments, when viewed from an angle orthogonal
to a plane containing the shaft on either side of the bend, have an
asymmetric marker having two portions. The first portion lies
substantially within a plane transverse to the center longitudinal
axis. The second portion lies substantially within a plane that
contains the center longitudinal axis. One embodiment has the
marker disposed proximal of the bend, while the other embodiment
has the marker disposed distal of the bend. One embodiment
indicates shaft rotation proximal of the bend directly and infers
the orientation of the segment distal of the bend. Another
embodiment indicates shaft rotation distal of the bend directly and
infers the orientation of the segment proximal of the bend. The
other embodiment, not requiring illustration, has both the markers
of FIGS. 5A through 5C and 6A through 6C on the same shaft.
[0043] FIG. 7 illustrates a catheter shaft 200 having a radiopaque
marker 201 including a first portion 206 and a second portion 208.
Catheter 200 has a bend 202 and-a distal end 204. In the embodiment
illustrated, catheter 200 has a lumen 210 extending therethrough.
As can be seen from inspection of FIG. 7, a plane bisecting the
center longitudinal axis through catheter shaft 200 would bisect
radiopaque marker 201 into two halves 206 and 208, with the halves
being asymmetric relative to the bisecting plane. In particular,
first marker portion 206 and second marker portion 208 are not
mirror images of each other with respect to a bisecting plane
sending through the central axis. Radiopaque marker 201 is also not
symmetrical with respect to a transverse bisecting plane. The
asymmetry causes marker 201 to appear differently depending on the
rotation of the tube with respect to a viewer. In particular,
marker 201 will appear differently under fluoroscopy depending on
the degree to which the catheter is rotated about its central,
longitudinal axis proximal of bend 202.
[0044] FIG. 8A illustrates a catheter shaft 220 somewhat similar to
catheter shaft 200 of FIG. 7. Catheter shaft 220 has a distal end
224, a first or left marker portion 226, and a second or right
marker portion 228. Together, first and second marker portions 226
and 228 form an asymmetric marker 230 which is asymmetric about a
bisecting plane extending through the center longitudinal axis of
catheter shaft 220. In FIG. 8A, catheter shaft 220 is rotated such
that catheter distal end 224 is disposed at an angle of zero
degrees (0.degree.) relative to the viewer. Catheter shaft distal
end 224 is directed directly at the viewer. FIG. 8B illustrates
catheter shaft 220 rotated at a forty-five degree (45.degree.)
angle relative to the viewer, yet still remaining in a somewhat
forward disposition. Similarly, FIG. 8C illustrates catheter 220
rotated at ninety degrees (90.degree.) relative to the viewer, and
FIG. 8D has the catheter pointed at a one hundred thirty five
degree (135.degree.) angle away from the viewer. FIG. 8E
illustrates catheter shaft 220 being pointed directly away from the
viewer, followed by FIG. 8F, which illustrates the same catheter
pointing away from the viewer, but at an angle of two hundred
twenty five degrees (225.degree.). FIG. 8G illustrates catheter
shaft 220 being rotated sufficiently to point two hundred seventy
degrees (270.degree.) relative to the line of view, toward the
side. Finally, FIG. 8H illustrates catheter shaft 220 being pointed
three hundred fifteen degrees (315.degree.) away from its initial
location, pointing mainly toward the viewer, but at a slight angle
to the left.
[0045] As can be seen from inspection of FIGS. 8A through 8H,
catheter marker 230 appears differently under fluoroscopy depending
on the rotation of the marker relative to the viewer. In
particular, the marker is asymmetrically disposed on the catheter
shaft such that rotation of the catheter about its longitudinal
center axis appears different, relative to a fixed viewer
orthogonal to the longitudinal axis of the catheter shaft. Marker
201 thus enables a viewer using fluoroscopy to determine the angle
of rotation of the catheter shaft about its longitudinal axis. This
can prove useful in a myocardial revascularization procedure, where
turning the catheter in varying degrees can be important, as the
degree of rotation may correspond to the location of holes formed
in the heart chamber wall.
[0046] FIG. 9A illustrates a catheter shaft 240 having a bend 242
and a distal end 244. Catheter shaft 240 further has a first
radiopaque marker band 246 and a second radiopaque marker band 248
disposed at a known distance "D1" apart. In a preferred embodiment,
marker bands 246 and 248 are disposed at a distance apart of
between about 1-2 cm. FIG. 9B illustrates catheter 240 being
rotated toward and to the left of the viewer. A treatment catheter
250 may be seen to extend from catheter shaft distal end 244.
Treatment catheter 250 may be seen to have a therapeutic tip 252. A
first treatment site 254 is represented by an "X" in FIG. 9B. As
illustrated in FIG. 9B, therapeutic tip 252 has been moved to a
distance of about "D2" from first treatment site 254. In the
embodiment illustrated, therapeutic tip 252 is about to treat a
second site 256, where the inter-site distance, D2, is
substantially equal to the D1 distance. The marker bands may thus
be used as a scale to accurately space the treatments sites in the
heart chamber wall. The marker bands, being spaced apart about the
same distance as the desired treatment spacing, will be subject to
the same magnifications and/or distortions under fluoroscopy. This
means that even if the distance between the markers appears
distorted under fluoroscopy, the distance between target sites will
likewise be distorted by about the same amount.
[0047] FIG. 10 illustrates a PMR catheter 280 including an inner
needle 282 rotatably disposed within an outer tube 284. Inner
needle 282 includes a shaft 286, and can terminate distally in a
sharp needle tip 288. Outer tube 284 includes a tube wall 290, and
has a distal flange or hood 292. A hole 293 is disposed within
distal flange 292 for receiving needle tip 288. In the embodiment
illustrated, inner needle 282 has an inner stop 294 secured to
inner shaft 286. Inner stop 294 is secured to inner shaft 286 such
that rotating the inner shaft rotates the inner stop. In this
embodiment, outer tube 284 has outer stops 295, 296, and 297
secured at various longitudinal and angular locations along tube
wall 290. As can be seen from inspection of FIG. 10, inner stop
294, if advanced further distally, will encounter outer stop 295
which will limit the distal travel of needle tip 288. It may also
be seen that rotating inner shaft 286 by ninety degrees
(90.degree.) will allow inner stop 294 to clear outer stop 294 and
proceed distally further. In an embodiment where inner stop 294 has
a hemispherical configuration, rotating inner shaft 286 by one
hundred eighty degrees (180.degree.) would allow needle tip 288 to
travel distally, yet be stopped by outer stop 296, again requiring
one hundred eighty degree (180.degree.) rotation to allow further
distal travel of the needle tip. Thus, twisting the inner shaft can
allow the depth of penetration to be controlled. In some
embodiments, the inner and outer stops are formed of radiopaque
material, allowing the degree of penetration to be observed under
fluoroscopy. Having staggered stops, as illustrated in FIG. 10,
allows the penetration depths to be accurately controlled from the
proximal end of the catheter. This may be of particular importance
in PMR procedures due to the varying thickness of the heart
wall.
[0048] FIG. 11A illustrates a PMR device 400 extending from a
proximal region 402 to a distal region 404 and having a distal
flange 410. PMR device 400 includes an outer tube 408 defining an
outer lumen 412 within and slidably containing an inner tube 414
having a first lumen 416 and a second lumen 418 disposed within. In
one embodiment, the two lumens are formed within a multi-lumen
extrusion of inner tube 414. In another embodiment, the two lumens
416 and 418 are defined by separate tubes which are joined together
along their length. First lumen 416 may have a fluid injected
through a first manifold port 420 disposed in proximal region 402
extending through a first access tube 417 which can define first
lumen 416 in the proximal region. First lumen 416 extends distally
to a first injection needle 426 which may be seen to have an
arcuate distal region 427. Similarly, second lumen 418 may be seen
to extend from a second manifold port 422, through a second
proximal tube 419, extending distally to a second fluid injection
needle 428. In the embodiment illustrated, first injection needle
426 is curved, while second injection needle 428 is substantially
straight in the distal region.
[0049] In one embodiment, first lumen 416 is used to inject
radiopaque fluid, while second lumen 418 is used to inject a drug
as part of the PMR procedure. In another embodiment, first lumen
416 is used to inject a drug, while second lumen 418 is used to
inject a radiopaque material. In this latter embodiment, the
straight needle 428 can be used to inject radiopaque material at
the center of a circular pattern formed by the repeated injection
of a drug through first needle 426. Injection of the radiopaque
fluid allows the treating physician to visualize under fluoroscopy
which areas of the heart wall have already been treated with the
drug.
[0050] FIG. 11B illustrates a distal PMR device region 434, similar
to distal region 404 of FIG. 11A, and having similar proximal
regions, but having a different configuration for the two distal
needles. In the embodiment illustrated, the PMR device distal
region includes outer tube 408, inner tube 414, and first and
second lumens 416 and 418, as in FIG. 11A. First needle 426 has
arcuate region 427. In this embodiment, a second needle 430 is
illustrated, also having arcuate distal segment 432. In this
embodiment, both first and second needles have arcuate distal
regions. FIG. 11C illustrates distal region 434 of FIG. 1B, shown
in a retracted configuration. First needle 426 and second needle
430 may be seen to be retracted within outer tube 408.
[0051] FIGS. 12A and 12B illustrate other embodiments of PMR device
distal regions, with the proximal regions not requiring
illustration and having somewhat similar designs to those of FIG.
11A. FIG. 12A illustrates a PMR device 440 including a distal
region 444 and having a distal atraumatic flange 446. PMR device
440 includes an outer tube 448 defining an outer lumen 450 within.
Outer lumen 450 includes within an intermediate or first tube 452
defining an intermediate or first lumen 454 within. Intermediate
lumen 454 includes within an inner or second tube 456 defining an
inner or second lumen 458 within. Intermediate lumen tube 452
extends distally and terminates in a distal injection tip 462.
Second or inner tube 456 extends distally, terminating in a distal
injection tip 463.
[0052] In one embodiment, first lumen 454 is used to inject a drug
through needle 462. In this embodiment, second or intermediate
lumen 458 is used to inject a radiopaque dye through second or
intermediate needle 463. In the embodiment illustrated in FIG. 12A,
intermediate tube 452 can be slidably disposed within the outer
tube 444, and can have inner tube 456 slidably disposed within. In
another embodiment, the functions of the first and second lumens
are reversed relative to the aforementioned embodiment. In this
embodiment, inner needle 463 is used to inject dye, while
intermediate needle 462 is used to inject a drug. Injecting a
radiopaque dye or contrast media allows the treating physician to
observe which areas of the heart wall have been treated and which
have not been treated, under fluoroscopy.
[0053] FIG. 12B illustrates a PMR device 480 including a distal
region 484 and having a distal atraumatic flange 486. A first
material may be injected through a proximal manifold port, through
a first lumen 492 defined within a first or intermediate tube 490.
The first material or fluid may be injected through intermediate
tube 490, being injected into tissue through a first distal tip
494. A second material or fluid may be injected through a second or
inner manifold port, flowing through an inner lumen 500 defined
within an inner tube 498. The second media may be injected distally
into tissue through a inner distal tip 502.
[0054] In the illustrated embodiment, tube 490 is fixed relative to
outer tube 484, while inner tube 498 can be slidably disposed with
respect to tube 490. In this embodiment, radiopaque contrast media
may be injected at approximately the same site as a drug delivered
in a PMR procedure. In one embodiment, a drug is injected through
inner tip 502, while a contrast media is injected through tip 494.
In another embodiment, contrast media is injected through tip 502,
while a drug or other therapeutic substance is delivered through
the outer distal tip 494. In the embodiment illustrated in FIG.
12B, outer distal tip 494 is relatively rounded at the end, with
pressure being used to force material into the heart wall, rather
than relying primarily on needle penetration. PMR device 480 also
allows injection of contrast media near the site of drug injection.
This allows the treating physician to observe the location of sites
treated by PMR under fluoroscopy, distinguishing the treated sites
from the untreated areas.
[0055] Numerous advantages of the invention covered by this
document have been set forth in the foregoing description. It will
be understood, however, that this disclosure is, in many respects,
only illustrative. Changes may be made in details, particularly in
matters of shape, size, and arrangement of parts without exceeding
the scope of the invention. The invention's scope is, of course,
defined in the language in which the appended claims are
expressed.
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