U.S. patent application number 16/923885 was filed with the patent office on 2020-10-29 for catheter system and method for occluding a body vessel.
The applicant listed for this patent is Miracor Medical SA. Invention is credited to Jon H. Hoem, Oliver A. Kohr.
Application Number | 20200337564 16/923885 |
Document ID | / |
Family ID | 1000004942939 |
Filed Date | 2020-10-29 |
United States Patent
Application |
20200337564 |
Kind Code |
A1 |
Hoem; Jon H. ; et
al. |
October 29, 2020 |
Catheter System and Method For Occluding A Body Vessel
Abstract
Some embodiments of a balloon catheter device for introduction
into a body vessel, in particular the coronary sinus, can include a
catheter shaft which carries an inflatable balloon on its distal
portion and in which a plurality of different lumens are formed. In
particular embodiments, a system for treating heart tissue can
include a coronary sinus occlusion catheter configured for improved
deliverability to the coronary sinus and for thereafter performing
intermittent occlusion of the coronary sinus.
Inventors: |
Hoem; Jon H.; (Oberaegeri,
CH) ; Kohr; Oliver A.; (Worb, CH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Miracor Medical SA |
Vienna |
|
AU |
|
|
Family ID: |
1000004942939 |
Appl. No.: |
16/923885 |
Filed: |
July 8, 2020 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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12786743 |
May 25, 2010 |
10743780 |
|
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16923885 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61M 25/10 20130101;
A61M 2025/1093 20130101; A61M 2025/0063 20130101; A61M 2025/0003
20130101; A61M 25/0054 20130101; A61M 25/0069 20130101; A61M 25/007
20130101; A61M 25/0032 20130101; A61M 25/10188 20131105; A61B
5/0215 20130101; A61M 25/10184 20131105; A61M 2025/1052
20130101 |
International
Class: |
A61B 5/0215 20060101
A61B005/0215; A61M 25/00 20060101 A61M025/00; A61M 25/10 20060101
A61M025/10 |
Claims
1. An occlusion catheter device for intermittently occluding a
coronary sinus, comprising: a catheter shaft that carries an
inflatable balloon on a distal portion; a pressure sensor lumen
extending centrally through the catheter shaft to a plurality of
distal ports that are positioned distally of the balloon for
communication with fluid in a coronary sinus; an inflation lumen to
inflate and deflate the balloon; a stiffening element extending
along the catheter shaft, the stiffening element having a distal
end portion that is positioned adjacent to the proximal end of the
balloon and has a flexural strength reduced relative to a remaining
proximal portion of the stiffening element.
2. The catheter device of claim 1, wherein the stiffening element
comprises a hypotube surrounding the catheter shaft.
3. The catheter device of claim 2, wherein the stiffening element
substantially extends over the entire portion of the catheter shaft
between the balloon and a proximal hub portion.
4. The catheter device of claim 2, wherein the distal end portion
of the stiffening element having the reduced flexural strength
extends over a length of about 40 mm to about 90 mm.
5. The catheter device of claim 2, wherein the hypotube comprises
at least one notch influencing the flexural strength.
6. The catheter device of claim 5, wherein the notch extends in a
helical line-shaped manner, with the helical line having a smaller
pitch in the distal end portion of the stiffening element having
the reduced flexural strength than in the remaining proximal
portion of the stiffening element.
7. The catheter device of claim 5, wherein the pitch of the helical
line continuously increases in the distal end portion of the
stiffening element having the reduced flexural strength, departing
from the distal end of the hypotube.
8. The catheter device of claim 1, wherein the lumens extending
through the catheter shaft have cross-sectional geometries
differing from one another.
9. The catheter device of claim 8, wherein the inflation lumen has
a ring segment-shaped in cross section and is arranged radially
outside the pressure sensor lumen extending centrally through the
catheter shaft.
10. The catheter device of claim 9, further comprising wherein a
balloon pressure-monitoring lumen to measure the pressure in the
balloon, the balloon pressure-monitoring lumen having a ring
segment-shaped in cross section and being arranged the pressure
sensing lumen extending centrally through the catheter shaft,
wherein an arc-determining angle of the balloon pressure-monitoring
lumen is smaller as compared to that of the inflation lumen.
11. The catheter device of claim 10, further comprising a circular
or oval lumen provided between the neighboring ends of the ring
segment-shaped cross sections of the inflation lumen and the
balloon pressure-monitoring lumen.
12. The catheter device of claim 10, wherein the inflation lumen
and the balloon pressure-monitoring lumen are each connected with
the interior of the balloon via at least two radial openings
arranged to be offset in an axial direction of the catheter
shaft.
13. The catheter device of claim 1, further comprising a stiffening
wire extending through a lumen of the catheter shaft in a region
adjacent to the balloon, said wire extending along a length of the
balloon.
14. The catheter device of claim 1, further comprising a catheter
tip element in fluid communication with the pressure sensor lumen
extending centrally through the catheter shaft, the catheter tip
element defining the plurality of distal ports that are positioned
distally of the balloon for communication with fluid in a coronary
sinus, the plurality of distal ports comprising a plurality of
radial openings that are substantially uniformly distributed over a
circumferential periphery of the catheter tip element.
15. The catheter device of claim 14, wherein a distal edge of a
distal opening of the catheter tip element is rounded off.
16. The catheter device of claim 15, wherein the catheter tip
element conically tapers toward the distal opening.
17. The catheter device of claim 14, wherein the catheter tip
element comprises a flexible material.
18. The catheter device of claim 14, wherein a distance between a
distal end of the catheter tip element and the distal end of the
inflatable portion of the balloon is about 35 mm to about 45
mm.
19. A coronary sinus occlusion catheter device, comprising: a
catheter shaft that carries an inflatable balloon on a distal
portion; a pressure sensor lumen extending centrally through the
catheter shaft to a plurality of distal ports that are positioned
distally of the balloon for communication with fluid in a coronary
sinus; an inflation lumen to inflate and deflate the balloon; and a
balloon pressure-monitoring lumen to measure the pressure in the
balloon, the balloon pressure-monitoring lumen being different from
and adjacent to the inflation lumen, wherein both the inflation
lumen and the balloon pressure-monitoring lumen are in fluid
communication with an interior of the balloon.
20. The catheter device of claim 1, further comprising a stiffening
element extending along the catheter shaft, the stiffening element
having a distal end portion that is positioned adjacent to the
proximal end of the balloon and has a flexural strength reduced
relative to a remaining proximal portion of the stiffening element.
Description
TECHNICAL FIELD
[0001] This document relates to a balloon catheter for introduction
into a body vessel, such as the coronary sinus, and the occlusion
of the same, including a catheter shaft which carries an inflatable
balloon on its distal end portion and in which a plurality of
lumens are formed.
BACKGROUND
[0002] Balloon catheters including inflatable balloons can, for
instance, be taken from EP 402964 B1. The known balloon catheter
serves for coronary sinus occlusion, wherein diagnostically
valuable signals can be obtained by a plurality of sensors and the
inflation of the balloon can be controlled, in particular, with a
view to achieving retroperfusion. Such a balloon catheter is also
known as a multi-lumen catheter, whose distal end projects, for
instance, into the coronary sinus of the heart, while the proximal
end of the catheter is connected with a pump for inflating the
balloon. Wires for electrically contacting sensors can be conducted
through further lumens arranged coaxially or in parallel with the
lumen that serves to inflate the expandable balloon. Via such
further lumens, cardioplegic or thrombolytic, or other
pharmacologically active substances suitable for retroperfusion in
ischemic tissue, can also be introduced.
[0003] In order to supply ischemic tissue with blood by retrograde
perfusion, it has already been proposed to use an inflatable
balloon fixed to the end of a catheter to intermittently occlude
the coronary sinus. The blood pressure in the coronary sinus rises
during the occlusion at every heart beat so as to cause blood
reaching the coronary sinus through the healthy tissue of the heart
muscle to be flushed back into the ischemic tissue. Another effect
of intermittent occlusion is the influence on the pressure
regulation due to the feedback mechanism by neuro-stimulative
effects. For such intermittent coronary sinus occlusion, the
balloon end of the catheter is inserted either percutaneously or
surgically. The other end of the catheter is supplied by a pump
with a gas or fluid which causes the cyclic inflation and deflation
of the balloon. A device for the retroperfusion of coronary veins
is, for instance, known from WO 2005/120602 A1, by which a
pressure-controlled, intermittent coronary sinus occlusion can be
performed. In that device and the corresponding method for
determining the optimum times for triggering and releasing the
occlusion, pressure parameters like the speeds of the pressure
increase and pressure drop were determined and subjected to
relatively complex processing.
[0004] For the percutaneous insertion of a catheter, it is
proceeded in a manner that the catheter is guided via the inferior
or the superior cava vein into the right atrium of the heart, into
which the coronary sinus runs. Due to the position of the mouth of
the superior cava vein or inferior cava vein, respectively,
relative to the mouth of the coronary sinus, the introduction of
the catheter into the coronary sinus requires considerable skill
from the cardiologist in order to direct the tip of the catheter,
or a guide wire or a guide sleeve, into the coronary sinus in such
a manner as to enable the subsequent introduction of the catheter
along with the occlusion device. In fact, it frequently happened
that several attempts of introduction into the coronary sinus had
to be made, which considerably extended the duration of treatment
and, hence, the strain on the patient.
[0005] Another problem involved in balloon catheters used for the
intermittent occlusion of the coronary sinus resides in that blood
backed up during the occlusion would exert pressure on the balloon,
and hence on the catheter, thus eventually causing the catheter to
slip back or kink within the vessel.
SUMMARY
[0006] Some systems and methods described herein include an
occlusion catheter device that is sufficiently rigid in order to
reduce the likelihood the occlusion catheter device will slip back
from the occluded position because of the counter-pressure in the
occluded vessel. At the same time, the occlusion catheter device
may provide sufficient flexibility in order to enable the occlusion
catheter device to be safely pushed forward through blood vessel
regions having small radii of curvature so as to be able to
position an inflatable balloon on the catheter device at the
desired site of application (e.g., the coronary sinus in some
embodiments).
[0007] In particular embodiments, a balloon catheter which is
suitable for the intermittent occlusion of a body vessel (e.g., the
coronary sinus) can be equipped with the lumens required performing
the intermittent occlusion of the body vessel. The balloon catheter
can be configured to exhibit both sufficient flexural strength to
enhance the pushability of the catheter while also reducing the
likelihood that the balloon will not slip back on account of the
pressure caused by the backed-up fluid in the occluded vessel, and
sufficient flexibility to facilitate its introduction.
[0008] In some embodiments, the balloon catheter can include a
central lumen having a distal opening in communication with the
respective body vessel distally of the balloon. Furthermore, a
lumen serving to inflate and deflate the balloon and communicating
with the latter is provided. Also, the balloon catheter may include
a stiffening element surrounding at least a portion of the catheter
shaft, or arranged within at least a portion of the catheter shaft.
A distal end portion of the stiffening member, which may be
positioned adjacent to the proximal end of the balloon, can have a
flexural strength that is reduced relative to the remaining portion
of the stiffening element.
[0009] The central lumen of the balloon catheter, which includes
the distal opening into the respective body vessel distally of the
balloon, enables measurement of the pressure prevailing in the body
vessel occluded by the balloon (e.g., the coronary sinus pressure
in the coronary sinus). In some circumstances, the central lumen
also enables the taking of blood from the occluded vessel.
Moreover, the central lumen can be used to introduce the balloon
catheter into the vessel, and advance it within the vessel to the
respectively targeted site, by advancing the central lumen over a
guide wire.
[0010] In some embodiments, the flexural strength of the balloon
catheter is obtained by the stiffening element that surrounds the
catheter shaft, or is arranged within the catheter shaft. The
stiffening element also facilitates the advancement of the balloon
catheter. In order reduce the likelihood of injuring the vessel
during the advancement of the catheter, and to permit advancement
in curved regions having small radii of curvature, the distal end
portion of the stiffening element can be positioned adjacent to the
proximal end of the balloon and may provide a flexural strength
that is reduced relative to the remaining portion of the stiffening
element. Thus, a region of higher flexibility is deliberately
formed at the distal end portion of the stiffening element so as to
enable the adaptation to a curved course of the body vessel during
the advancement of the catheter, while preferably maintaining the
balloon-carrying, distal portion of the catheter in a generally
parallel relationship with the longitudinal extension of the
respective vessel in order to avoid injury to the vessel wall.
[0011] In particular embodiments, the stiffening element is
preferably formed by a hypotube surrounding the catheter shaft. The
stiffening element in this case preferably extends substantially
over the entire portion of the catheter shaft between the balloon
and the proximal end portion. In a preferred manner, a slight
distance is provided between the distal end of the stiffening
element and the proximal end of the inflatable region of the
balloon. In the embodiment described herein, the distance is
dimensioned such that, on the one hand, the catheter shaft will not
buckle between the distal end of the stiffening tube and the
balloon, which would be the case with too large a distance, and, on
the other hand, the flexibility and suppleness will not be limited
too much in this region, which would be the case with too short a
distance, or no distance at all. In some preferred embodiments, the
distance is about 4-6 mm and, in particular, about 5 mm.
[0012] In one aspect, the hypotube may be formed by a separate
stainless-steel tube or also by at least one outer layer
co-extruded with the catheter shaft and made of a synthetic
material differing from that of the catheter shaft. Alternatively,
the hypotube may be formed by a nylon tissue or comprise such a
tissue. In some embodiments, the portion of the stiffening element
having a reduced flexural strength extends over a length of about
30-120 mm, preferably about 40-90 mm, from the distal end of the
stiffening element.
[0013] According to a preferred configuration, the hypotube can
include at least one notch influencing the flexural strength. In
some embodiments, the notch preferably extends in a helical
line-shaped manner, with the helical line or helix having a smaller
pitch in the portion of reduced flexural strength of the hypotube
than in the remaining portion. As described herein, further
optimization is feasible in that the pitch of the helix
continuously increases in the portion of reduced flexural strength
of the hypotube, departing from the distal end of the hypotube. Due
to the continuously variable flexural strength of the hypotube in
the mentioned end portion, buckling sites will be avoided.
[0014] In alternative embodiments, instead of a helical line-shaped
notch, a plurality of notches offset in the axial direction may
also be provided on the stiffening element. Each of the notches can
extend over a partial circumference of the hypotube, with the
flexural strength depending on the axial distance between the
individual notches.
[0015] For the intermittent occlusion of a body vessel and, in
particular, the coronary sinus, a plurality of lumens are usually
required such that a particularly space-saving arrangement of the
individual lumens is useful in order to maintain the outer diameter
of the catheter shaft as small as possible. Accordingly, the lumens
of the catheter may have cross-sectional geometries differing from
one another. In some embodiments, the inflation lumen that serves
to inflate and/or deflate the balloon may have a ring
segment-shaped in cross section and arranged radially outside the
central lumen.
[0016] In some embodiments, a separate lumen in the balloon
catheter can be employed to monitor the fluid pressure prevailing
in the balloon. In particular embodiments, the balloon
pressure-monitoring lumen may have a ring segment-shaped in cross
section and arranged radially outside the central lumen, whose
arc-determining angle is preferably smaller as compared to the ring
segment-shaped inflation lumen serving to inflate and deflate the
balloon. Due to the fact that the ring segment-shaped cross section
of the inflation lumen extends over a larger central angle than the
ring segment-shaped cross section of the balloon
pressure-monitoring lumen, a larger cross section is provided for
the inflation lumen and, at the same time, separate pressure
measurements will be enabled, thus providing a configuration that
utilizes the catheter space while maintaining the outer diameter of
the catheter shaft accordingly small.
[0017] In particular embodiments, the ability for pressure
measurement via a separate lumen (e.g., the balloon
pressure-monitoring lumen that is separate from the inflation
lumen) can provide the advantage that possible buckling under
flexural load can be detected. Buckling can be reliably detected
due to the different pressures measured in the inflation lumen
serving to inflate and deflate the balloon and in the balloon
pressure-monitoring lumen. In such circumstances, it is thus
feasible to take the respective safety measurements, e.g. actuate a
safety valve, in due time.
[0018] According to a further preferred configuration, it is
provided that a circular or oval lumen is provided between the
neighboring ends of the ring segment-shaped lumens. Such a
relatively small lumen enables the wiring of electrical sensors
arranged in the tip of the catheter or in the region of the
balloon, or the arrangement of fiber-optic lines.
[0019] In order to avoid possible malfunctions during the inflation
and deflation of the balloon, it is provided according to a
preferred further development that the inflation lumen, and
optionally the balloon pressure-monitoring lumen, are each
connected with the interior of the balloon via at least two radial
openings arranged to be offset in the axial direction of the
catheter. The use of at least two radial openings into the interior
of the balloon can reduce the risk of the balloon prematurely
covering all openings, particularly during collapsing, i.e. prior
to the complete evacuation of the balloon, so that further
evacuation would be rendered difficult or impossible.
[0020] In some embodiments, the balloon catheter may include a
stiffening means, such as a stiffening wire, in the region of the
balloon. The stiffening wire may extend over the length of the
balloon, and may extend from a region interior to the previously
describe hypotube to a distal region interior to a distal collar of
the balloon. Such a stiffening means can reduce the likelihood of
the catheter shaft buckling or otherwise deforming in the region in
which it is surrounded by the balloon, on account of the balloon
pressure exerting axial upsetting forces on the catheter shaft. The
stiffening means can, for instance, be received in the circular or
oval lumen mentioned above. In an alternative embodiment, the
stiffening wire may be arranged in a helical wrap around an outer
circumference of the catheter shaft in the interior region of the
balloon.
[0021] In particular embodiments, the distal end of the catheter
can be connected with a catheter tip element which comprises an
axial lumen provided consecutively to the central lumen of the
catheter and having a distal opening, the wall of said axial lumen
including at least two, preferably three, radial openings uniformly
distributed over its periphery. Such a separate catheter tip
component offers various advantages in terms of application. Thus,
the edge of the distal opening of the catheter tip element may, for
instance, be rounded off so as to prevent damage to the vessel
walls. Furthermore, the catheter tip element may conically taper
toward the distal opening, and the catheter tip element may, in
particular, be designed to be flexible in order to ensure an
enhanced guidance of the tip, and hence the overall catheter,
within the body vessel. In this respect, the catheter tip element
should have a minimum length in order to provide an appropriate
bending zone. In a preferred manner, the distance between the
distal tip of the catheter tip element and the distal end of the
balloon is at least about 30 mm and, preferably, about 35 mm to
about 45 mm.
[0022] By the axial lumen of the catheter tip element communicating
with the body vessel not only via the distal opening of the
catheter tip element, but also via at least two, preferably three,
radial openings uniformly distributed over its periphery in the
wall of the catheter tip element, a more precise measurement of the
fluid pressure prevailing in the body vessel has become feasible.
In particular, the likelihood of faulty measurements can be reduced
because the radial openings can properly measure the fluid pressure
in the body vessel eve if the distal opening or one radial opening
were in abutment with the vessel wall, or if one opening was not
powered with the full pressure prevailing in the vessel for any
other reason.
[0023] The details of one or more embodiments of the invention are
set forth in the accompanying drawings and the description below.
Other features, objects, and advantages of the invention will be
apparent from the description and drawings, and from the
claims.
DESCRIPTION OF DRAWINGS
[0024] FIG. 1 is a perspective view of a portion of a system for
treating heart tissue, in accordance with some embodiments.
[0025] FIG. 2 is a perspective view of another portion of the
system of FIG. 1.
[0026] FIG. 3 is a schematic illustration of a catheter device of
the system of FIG. 1.
[0027] FIG. 4 is a detailed view of the balloon of the catheter
device of FIG. 3.
[0028] FIG. 5 shows a cross sectional view of the catheter device
of FIG. 3.
[0029] FIG. 6 shows a cross sectional view of a portion of the
catheter device of FIG. 4.
[0030] FIG. 7 is a cross-sectional view of a catheter tip element
of the catheter device of FIG. 3.
[0031] FIG. 8 is a perspective view of the catheter tip element of
FIG. 7.
[0032] FIG. 9 is a detailed view of a portion of the catheter of
FIG. 3 with the balloon removed from the view.
[0033] FIG. 10 is a detail view of a stiffening element for the
catheter of FIG. 3.
[0034] Like reference symbols in the various drawings indicate like
elements.
DETAILED DESCRIPTION
[0035] Referring to FIGS. 1-2, some embodiments of a system 100 for
treating heart tissue can include a coronary sinus occlusion
catheter 120 and a control system 140 (FIG. 2). In particular
embodiments, the control system 140 can be configured to control
the operation of the catheter 120 for providing pressure-controlled
intermittent coronary sinus occlusion (PICSO) and to receive heart
sensor data for display. The coronary sinus occlusion catheter 120
includes a distal tip portion 121 (leading to a distal end depicted
in FIG. 1) and a proximal portion 131, which includes a proximal
hub 132 that is coupled to the control system 140 via a number of
fluid or sensor lines 133, 134, and 135. Accordingly, the control
system 140 may be employed to operate one or more components at the
distal tip portion 121 of the coronary sinus occlusion catheter 120
while also receiving one or more sensor signals that provide data
indicative of heart characteristics (e.g., coronary sinus pressure,
electrocardiogram (ECG) information, and the like).
[0036] Briefly, in use, the distal tip portion 121 of the coronary
sinus occlusion catheter 120 can be arranged in a coronary sinus 20
of a heart 10 and thereafter activated to intermittently occlude
the blood flow exiting from the coronary sinus 20 and into the
right atrium 11. During such an occlusion of the coronary sinus 20,
the venous blood flow that is normally exiting from the coronary
sinus 20 may be redistributed into a portion of heart muscle tissue
30 that has been damaged due to blood deprivation. For example, the
portion of heart muscle tissue 30 can suffer from a lack of blood
flow due to a blockage 35 in a coronary artery 40. As a result, the
arterial blood flow to the affected heart muscle tissue 30 via a
local artery 41 can be substantially reduced such that the heart
muscle tissue 30 becomes ischemic or otherwise damaged. Further,
because the arterial blood flow is reduced, the venous blood flow
exiting from the local vein 21 is likewise reduced. Other branch
veins 22 located at different regions along the heart 10 may
continue to receive blood flow, thereby creating a supply of venous
blood flow exiting through the coronary sinus 20. In some
embodiments, the coronary sinus occlusion catheter 120 can be
delivered into the coronary sinus 20 and thereafter activated so as
to intermittently occlude the coronary sinus 20 before, during, or
after treating the blockage 35 on the arterial side. Such an
occlusion can cause the venous blood flow to be redistributed to
the local vein 21 and then into the portion of heart muscle tissue
30 can suffer from a lack of blood flow due to a blockage 35 in a
coronary artery 40. As such, the ischemic or otherwise damaged
heart muscle tissue 30 can be treated with the redistributed venous
blood flow in that the heart muscle tissue 30 receives
redistribution of flow before, during, and after the blockage 35 is
repaired or removed to restore normal coronary arterial blood
flow.
[0037] Furthermore, in use, the control system 140 (FIG. 2) is
configured to provide automated control of an occlusion component
(e.g., an inflatable balloon 122 or the like) of the coronary sinus
occlusion catheter 120. As described in more detail below, the
control system 140 includes a computer processor that executes
computer-readable instructions stored on a computer memory device
so as to activate or deactivate the occlusion in the coronary sinus
20 in accordance with particular patterns. For instance, the
control system 140 can be configured to activate the occlusion
component of the catheter 120 in the coronary sinus 20 as part of a
predetermined pattern of occlusion periods and release periods that
is independent of the coronary sinus pressure, or as part of a
pressure-dependent pattern that is at least partially defined by
the coronary sinus pressure readings during the procedure. In
addition, the control system 120 is equipped with a display device
142 having a graphical user interface that provides a cardiologist
or other user with time-sensitive, relevant data indicative of the
progress of a coronary sinus occlusion procedure and the condition
of the heart 10. As such, the user can readily monitor the
patient's condition and the effects of intermittently occluding the
coronary sinus 20 by viewing the graphical user interface while
contemporaneously handling the coronary sinus occlusion catheter
120 other heart treatment instruments (e.g., angioplasty catheters,
stent delivery instruments, or the like). It should be understood
from the description herein that, in some embodiments, the control
system 140 and the coronary sinus occlusion catheter 120 can be
used as part of a system for treating the heart muscle tissue
before, during, and after the blockage 35 is repaired or removed to
restore normal coronary arterial blood flow.
[0038] Referring in more detail to FIG. 1, the coronary sinus
occlusion catheter 120 can be delivered via the venous system to
the coronary sinus 20 before, during, or after repairing or
treating the blockage 35 the coronary artery 40. In such
circumstances, the portion of heart muscle tissue 30 that is
damaged due to lack of arterial blood flow (as a result of the
blockage) can be treated with a supply of venous blood while the
normal arterial blood flow is restored (as a result of repairing or
removing the blockage 35).
[0039] The system 100 may include a guide member 110 that is
advanced through the venous system of the patient and into the
right atrium 11. The guide member 110 in this embodiment comprises
a guide sheath having a lumen extending between a distal end 111
(FIG. 1) and a proximal end 112 (FIG. 4). In alternative
embodiments, the guide member 110 can include a guide wire having
an exterior surface extending between the distal end and the
proximal end. Optionally, the guide member 110 includes a steerable
mechanism to control the orientation of the distal end so as to
steer the distal end 111 through the venous system and into the
right atrium 11. Also, the guide member 110 can include one or more
marker bands along the distal end 111 so that the position of the
distal end can be monitored during advancement using an imaging
device.
[0040] After the guide member 110 is advanced into the right atrium
11, the distal end 111 may be temporarily positioned in the
coronary sinus 20. From there, the distal tip portion 121 of the
coronary sinus occlusion catheter 120 can be slidably advanced
along the guide member 110 for positioning inside the coronary
sinus 20. In the embodiments in which the guide member 110
comprises a guide sheath, the distal tip portion 121 of the
coronary sinus occlusion catheter 120 can slidably engage with an
interior surface of the lumen during advancement toward the
coronary sinus 20. In the alternative embodiments in which the
guide member 110 comprises a guide wire structure, the distal tip
portion 121 of the coronary sinus occlusion catheter 120 can
slidably advance over the exterior surface of the guide wire (e.g.,
a lumen of the catheter 120 passes over the guide wire) during
advancement toward the coronary sinus 20. After the coronary sinus
occlusion catheter 120 reaches the coronary sinus 20, the distal
end 111 of the guide member 110 can be withdrawn from the coronary
sinus 20 and remain in the right atrium 11 during use of the
coronary sinus occlusion catheter 120.
[0041] Still referring to FIG. 1, the distal tip portion 121 of the
coronary sinus occlusion catheter 120 that is positioned in the
coronary sinus 20 includes an occlusion component 122, which in
this embodiment is in the form of an inflatable balloon device. The
occlusion component 122 can be activated so as to occlude the
coronary sinus 20 and thereby cause redistribution of the venous
blood into the heart muscle tissue 30 that is damaged due to a lack
of arterial blood flow. As described in more detail below, the
inflatable balloon device 122 can be in fluid communication with an
internal lumen of the coronary sinus occlusion catheter 120, which
is in turn in communication with a pneumatic subsystem of the
control system 140 (FIG. 2). As such, the control system 140 can be
employed to expand or deflate the balloon device 122 in the
coronary sinus.
[0042] The distal tip portion 121 also includes a tip element 129
having one or more distal ports 127 (FIGS. 7-8) positioned distally
forward of the inflatable balloon device 122. In the depicted
embodiments, the distal ports 127 of the tip element 129 face is a
generally radially outward direction and are substantially
uniformly spaced apart from one another along the circumference of
the distal tip. As described in more detail below, the distal ports
127 of the tip element 129 may all be in fluid communication with a
single pressure sensor lumen 125 extending through the coronary
sinus occlusion catheter 120. Accordingly, the coronary sinus
pressure can be monitored via a pressure sensor device that is in
fluid communication with the distal ports 127 of the tip element
129.
[0043] Referring now to FIG. 2, the proximal portion 131 of the
coronary sinus occlusion catheter 120 and the control system 140
are positioned external to the patient while the distal tip portion
121 is advanced into the coronary sinus 20. The proximal portion
131 includes the proximal hub 132 that is coupled to the control
system 140 via a set of fluid or sensor lines 133, 134, and 135. As
such, the control system 140 can activate or deactivate the
occlusion component 122 at the distal tip portion 121 of the
coronary sinus occlusion catheter 120 while also receiving one or
more sensor signals that provide data indicative of heart
characteristics (e.g., coronary sinus pressure, electrocardiogram
(ECG) information, and the like).
[0044] The proximal hub 132 of the coronary sinus occlusion
catheter 120 serves to connect the plurality of fluid or sensor
lines 133, 134, and 135 with the portion of the coronary sinus
occlusion catheter 120 that extends into the patient's venous
system. For example, the first line 133 extending between the
control system 140 and the proximal hub 132 comprises a fluid line
through which pressurized fluid (e.g., helium, another gas, or a
stable liquid) can be delivered to activate the occlusion component
(e.g., to inflate the inflatable balloon device 122). The fluid
line 133 is connected to a corresponding port 143 of the control
system 140 (e.g., the drive lumen port in this embodiment) so that
the line 133 is in fluid communication with a pneumatic control
subsystem housed in the control system 140. The proximal hub 132
joins the first line 133 with an inflation lumen 158 (FIG. 5)
extending through the coronary sinus occlusion catheter 120 and to
the inflatable balloon device 122.
[0045] In another example, the second line 134 extending between
the control system 140 and the proximal hub 132 comprises a balloon
sensor line that is in fluid communication with the interior of the
inflatable balloon device 122 so as to measure the fluid pressure
within the balloon device 122. The proximal hub 132 joins the
second line 134 with a balloon pressure-monitoring lumen 159 (FIG.
5) extending through the coronary sinus occlusion catheter 120 and
to the inflatable balloon device 122. The pressure of the balloon
device 122 may be monitored an internal control circuit of the
control system 140 as part of a safety feature that is employed to
protect the coronary sinus 20 from an overly pressurized balloon
device 122. The balloon sensor line 134 is connected to a
corresponding port 144 of the control system 140 so that a pressure
sensor arranged within the control system 140 can detect the fluid
pressure in the balloon device 122. Alternatively, the pressure
sensor may be arranged in the distal tip portion 121 (e.g.,
internal to the balloon device 122) or the in the proximal hub 132
such that only a sensor wire connects to the corresponding port 144
of the control system 140.
[0046] The proximal hub 132 also connects with a third line 135
extending from the control system 140. The third line 135 comprises
a coronary sinus pressure line that is used to measure the fluid
pressure in the coronary sinus both when the balloon device 122 is
inflated and when it is deflated. The proximal hub 132 joins the
third line 135 with a pressure sensor lumen 125 (FIG. 5) extending
through the coronary sinus occlusion catheter 120 and to the distal
ports 129 that are forward of the balloon device 122. As such, the
pressure sensor lumen 125 can be a coronary sinus pressure lumen,
with at least a portion of the third line 135 may operating as a
fluid-filled path (e.g., saline, another biocompatible liquid, or a
combination thereof) that transfers the blood pressure in the
coronary sinus 20 to pressure sensor device 136 along a proximal
portion of the third line 135. The pressure sensor device 136
samples the pressure measurements (which are indicative of the
coronary sinus pressure) and outputs an sensor signal indicative of
the coronary sinus pressure to the corresponding port 145 of the
control system 140 for input to an internal control circuit (which
may include one or more processors that execute instructions stored
on one or more computer memory devices housed in the control system
140). The coronary sinus pressure data can be displayed by the
graphical user interface 142 in a graph form so that a cardiologist
or other user can readily monitor the trend of the coronary sinus
pressure while the coronary sinus 20 is in an occluded condition
and in a non-occluded condition. Optionally, the graphical user
interface 142 of the control system 140 can also output a numeric
pressure measurement on the screen so that the cardiologist can
readily view a maximum coronary sinus pressure, a minimum coronary
sinus pressure, or both. In alternative embodiments, the pressure
sensor device 136 can be integrated into the housing of the control
system 140 so that the third line 135 is a fluid-filled path
leading up to the corresponding port 145, where the internal
pressure sensor device (much like the device 136) samples the
pressure measurements and outputs a signal indicative of the
coronary sinus pressure.
[0047] Still referring to FIG. 2, the system 100 may include one or
more ECG sensors 149 to output ECG signals to the control system
140. In this embodiment, the system 100 includes a pair of ECG
sensor pads 149 that are adhered to the patient's skin proximate to
the heart 10. The ECG sensors 149 are connected to the control
system 140 via a cable that mates with a corresponding port 149
along the housing of the control system 140. As described in more
detail below, the ECG data can be displayed by the graphical user
interface 142 in a graph form so that a cardiologist or other user
can readily monitor the patient's heart rate and other
characteristics while the coronary sinus is in an occluded
condition and in an non-occluded condition. Optionally, the
graphical user interface 142 of the control system 140 can also
output numeric heart rate data (based on the ECG sensor data on the
screen so that the cardiologist can readily view the heart rate
(e.g., in a unit of beats per minutes). The ECG sensor signals that
are received by the control system 140 are also employed by the
internal control circuit so as to properly time the start of the
occlusion period (e.g., the start time at which the balloon device
122 is inflated) and the start of the non-occlusion period (e.g.,
the start time at which the balloon device 122 is deflated).
[0048] As shown in FIG. 2, the coronary sinus occlusion catheter
120 is delivered to the heart 10 via a venous system using any one
of a number of venous access points. Such access points may be
referred to as PICSO access points in some embodiments in which the
coronary sinus occlusion catheter 120 is controlled to perform a
PICSO procedure for at least a portion of the time in which the
catheter 120 is positioned in the coronary sinus 20. For example,
the guide member 110 and the distal tip portion 121 can be inserted
into the venous system into an access point at a brachial vein, an
access point at a subclavian vein, or at an access point at a
jugular vein. From any of these access points, the guide member 110
can be advanced through the superior vena cava and into the right
atrium 11. Preferably, the guide member 110 is steered into an
ostial portion of the coronary sinus 20, and then the distal tip
portion 121 of the catheter 120 is slidably advanced along the
guide member 110 and into the coronary sinus 20 before the guide
member 110 is backed out to remain in the right atrium 11. In
another example, the guide member 110 and the distal tip portion
121 can be inserted into the venous system into an access point at
a femoral vein. In this example, the guide member 110 can be
advanced through the inferior vena cava and into the right atrium
11. As previously described, the distal tip portion 121 of the
catheter 120 is slidably advanced along the guide member 110 and
into the coronary sinus 20 before the guide member 110 is backed
out to remain in the right atrium 11.
[0049] In some embodiments, the blockage 35 in the heart may be
repaired or removed using a percutaneous coronary intervention
(PCI) instrument such as an angioplasty balloon catheter, a stent
delivery instrument, or the like. The PCI instrument may access the
arterial system via any one of a number of PCI access points, as
shown in FIG. 2. In some implementations, the PCI instrument can be
inserted into the arterial system into an access point at a femoral
artery, an access point at a radial artery, or an access point at a
subclavian artery. Thus, as previously described, some embodiments
of the system 100 may employ a PICSO access point into the venous
system while a PCI access point is employed to insert a PCI
instrument into the arterial system.
[0050] Referring now to FIG. 3, the catheter device 120 carries the
balloon device 122 along its distal end portion. On its proximal
end, the catheter 120 comprises a the hub portion 132, in which the
proximal connection lines 133, 134, and 135 (not shown) are each
connected with the respective lumens of the catheter 120 via a
Y-connector 139. Alternatively, a multiple outlet for a plurality
of feeds may be provided. One of the two proximal connection lines
133 is connected with the lumen (e.g., inflation lumen 158 (FIG. 5)
serving to inflate and deflate the balloon 122 and carries a
proximal connection piece 137 to which a fluid source may be
connected. The other of the proximal connection lines 134 is
connected with the lumen (balloon pressure-monitoring lumen 159
(FIG. 5) serving to measure the pressure internal to the balloon
122, and carries a proximal connection piece 137 which can be
connected with an appropriate pressure measuring means. Finally, a
Luer lock 138 may be guided out of the hub portion 132 for
connection with the central lumen 125 (e.g., the pressure sensor
lumen) of the catheter 120.
[0051] The distance between the tip of the catheter tip element 129
and the hub portion 132 is denoted by a and is, for instance, about
one meter in order to enable the catheter to be introduced both via
the jugular vein and via the femoral vein or the vein of the upper
arm. A protective hose 10, which can be slipped over the catheter
tip element 129 and the balloon 122 in the direction of arrow 11,
is provided to protect the balloon 122 during the storage of the
catheter 120.
[0052] From the detailed view according to FIG. 2, it is apparent
that the balloon 122, in the inflated state, has a central,
approximately cylindrical portion 152 which is adjoined by a
conical portion 153 on either side, said conical portion 153 being
each connected with the catheter shaft 155 via a collar-shaped end
piece 154. In the inflated state, the diameter of the balloon 122
in the region of the cylindrical portion 152 may be, for instance,
between about 12 mm and about 22 mm and, preferably, about 15 mm.
The length b of the inflated portion of the balloon 122 may be, for
instance, between about 20 mm and about 30 mm and, preferably,
about 25 mm. By a marker band 156 positioned in the balloon 122 can
carry an X-ray-compatible material so as to be rendered visible
during a surgery by suitable imaging processes.
[0053] In accordance with some embodiments, the catheter shaft 155
may include a plurality of lumens extending from the hub portion
132 to the distal portion 121 (e.g., to the balloon 122 or to the
tip element 129). As shown in the cross-sectional illustration
according to FIG. 5, the catheter 120 has the central lumen 125
(e.g., the pressure sensor lumen in this embodiment) as well as two
ring segment-shaped lumens 158 and 159. The ring segment-shaped
lumen 158 (e.g., the inflation lumen in this embodiment), which
extends over a larger central angle than the ring segment-shaped
lumen 159 (e.g., the balloon-pressure monitoring lumen in this
embodiment), thereby providing a larger arc length than the ring
segment-shaped lumen 159. The inflation lumen 158 likewise
communicates with the interior of the balloon 122 and serves to
inflate and deflate the balloon 122. The balloon-pressure
monitoring lumen 159 likewise communicates with the interior of the
balloon 122 and serves to measure the pressure prevailing within
the balloon 122.
[0054] From FIG. 9 (which illustrates a portion of the catheter 120
that is interior to the balloon 122 (with the balloon 122 removed
from view), it is apparent that the lumens 158 and 159 are each in
communication with the interior of the balloon via two openings 160
and 161 respectively provided in an axially offset manner. The use
of at least two radial openings 160 and 161 into the interior of
the balloon 122 can reduce the risk of the balloon prematurely
covering all openings, particularly during collapsing, i.e. prior
to the complete evacuation of the balloon, so that further
evacuation would be rendered difficult or impossible. Between the
mutually adjacent ends of the ring segment-shaped lumens 158 and
159, a lumen 157 having a circular cross section is arranged.
Through the lumen 157, electric wirings, sensors or the like can be
conducted. Also, in some embodiments, in the lumen 157, a
stiffening wire (refer to wire 25 in FIG. 7) can be arranged in the
region of the balloon 122, as will be described in more detail
below. In addition or in the alternative, electric wirings, sensors
or the like can also be conducted through the central lumen
157.
[0055] Accordingly, the lumens 125, 157, 158, and 159 of the
catheter device 120 may have cross-sectional geometries differing
from one another. For example, the inflation lumen 158 that serves
to inflate and/or deflate the balloon may have a ring
segment-shaped in cross section and arranged radially outside the
central lumen 125. The second lumen 159 (e.g., the balloon
pressure-monitoring lumen in this embodiment) may have a ring
segment-shaped in cross section and arranged radially outside the
central lumen 125, and the arc-determining angle is preferably
smaller as compared to the ring segment-shaped inflation lumen 158.
Due to the fact that the ring segment-shaped cross section of the
inflation lumen 158 extends over a larger central angle than the
ring segment-shaped cross section of the balloon
pressure-monitoring lumen 159, a larger cross section is provided
for the inflation lumen 158 and, at the same time, separate
pressure measurements will be enabled. The ability to provide
pressure measurements via the separate lumen 159, for instance, has
the advantage that possible buckling under flexural load (or
kinking) can be detected. Buckling can be reliably detected due to
the different pressures measured in the inflation lumen 158 and in
the separate lumen 159. In such circumstances, it is thus feasible
to take the respective safety measurements, e.g. actuate a safety
valve, in a prompt manner. From the cross-sectional illustration
according to FIG. 6, it is apparent that a stiffening element 23 in
the form of a hypotube surrounds the catheter shaft 155 is arranged
at a distance c (FIG. 2) from the proximal end of the balloon 2. An
example embodiment of the hypotube 23 is illustrated in FIG. 10. As
shown in FIG. 7, the stiffening wire 165 made, for instance, of
nitinol may be arranged in the lumen 157. The stiffening wire 165
may extend over the length of the balloon 122 so as to reduce the
likelihood of the catheter shaft 155 buckling or otherwise
deforming in the region in which it is surrounded by the balloon
122, on account of the balloon pressure exerting axial upsetting
forces on the catheter shaft 155.
[0056] An example embodiment of the catheter tip element 139 is
illustrated in detail in FIG. 7. There, the attachment of the
collar 154 of the balloon 122 to the distal end of the catheter is,
in particular, illustrated. The connection is realized via an
interposed, distal filling member 166, whereby a material adhesion
of the collar 154 with the catheter upon interposition of the
filling member 166 is effected in this region by thermal bonding or
gluing. A further marker band 167 can be arranged at a distance d
(e.g., about 6.5 mm in this embodiment) from the distal opening 28
of the catheter tip element 129. The catheter tip element 129 is
connected with the distal end of the catheter by the aid of a
transition piece 169. It is apparent that the axial lumen 126 of
the catheter tip element 129 is arranged immediately consecutive to
the central lumen 125 of the catheter. The catheter tip element 129
comprises a portion conically tapering toward the distal opening
128 and including three openings 127 uniformly distributed about
its periphery.
[0057] From the perspective illustration according to FIG. 8, it is
apparent that the edge 162 of the distal opening 128 is rounded off
in order to avoid damage to the vessel inner wall.
[0058] FIG. 10 depicts a hypotube 123 which comprises a helical
line-shaped notch 163. It is apparent that the pitch of the helix
163 in the distal end portion 164 is smaller than in a more
proximally located region 165. This results in a reduced flexural
strength in the distal end portion 164 so as to enable the catheter
to better follow the various curvatures of the body vessel during
its introduction. In some embodiments, the pitch of the helix 163
at the distal end portion 164 relative to the pitch of the helix at
the proximally located region 165 can be selected so that the
flexural strength is a function of the length of the catheter
leading up to the balloon
[0059] Thus, as described herein, the catheter 120 can be
configured to provide sufficient rigidity in order to reduce the
likelihood the occlusion catheter device will slip back from the
occluded position because of the counter-pressure in the occluded
vessel. At the same time, the catheter 120 may provide sufficient
flexibility in order to enable the catheter 120 to be safely pushed
forward through blood vessel regions having small radii of
curvature so as to be able to position the inflatable balloon 122
on the catheter 120 at the desired site of application (e.g., the
coronary sinus 20).
[0060] In some embodiments, the flexural strength of the balloon
catheter 120 is obtained by the stiffening element 123 that
surrounds the catheter shaft 15. The stiffening element 123 also
facilitates the advancement of the balloon catheter. In order
reduce the likelihood of injuring the vessel during the advancement
of the catheter, and to permit advancement in curved regions having
small radii of curvature, the distal end portion 164 of the
stiffening element 123 can be positioned adjacent to the proximal
end of the balloon 122 and may provide a flexural strength that is
reduced relative to the remaining portion of the stiffening
element. Thus, a region of higher flexibility is deliberately
formed at the distal end portion 164 of the stiffening element 123
so as to enable the adaptation to a curved course of the body
vessel during the advancement of the catheter 120, while preferably
maintaining the balloon-carrying, distal portion 121 of the
catheter 120 in a generally parallel relationship with the
longitudinal extension of the respective vessel in order to avoid
injury to the vessel wall.
[0061] In particular embodiments, the stiffening element 23 may
extend substantially over the entire portion of the catheter shaft
155 between the balloon 122 and the proximal hub portion 132. In a
preferred embodiment, the distance c is provided between the distal
end of the stiffening element 123 and the proximal end of the
inflatable region of the balloon 122. In the embodiment described
herein, the distance c is dimensioned such that, on the one hand,
the catheter shaft will not buckle between the distal end of the
stiffening tube and the balloon, which would be the case with too
large a distance, and, on the other hand, the flexibility and
suppleness will not be limited too much in this region, which would
be the case with too short a distance, or no distance at all. In
some preferred embodiments, the distance c is about 4-6 mm and, in
particular, about 5 mm.
[0062] As shown in FIG. 10, the stiffening element 23 may be formed
by a separate stainless-steel tube or also by at least one outer
layer co-extruded with the catheter shaft 155 and made of a
synthetic material differing from that of the catheter shaft 155.
Alternatively, the stiffening element 23 may be formed by a nylon
tissue or comprise such a tissue. In some embodiments, the portion
of the stiffening element having a reduced flexural strength
extends over a length of about 30-120 mm, preferably about 40-90
mm, from the distal end of the stiffening element.
[0063] According to a preferred configuration, the hypotube 23 can
include at least one notch influencing the flexural strength. In
the embodiment depicted in FIG. 10, the notch 163 preferably
extends in a helical line-shaped manner, with the helical line or
helix having a smaller pitch in the portion of reduced flexural
strength of the hypotube than in the remaining portion. As
described herein, further optimization is feasible in that the
pitch of the helix 163 continuously increases in the portion of
reduced flexural strength of the hypotube, departing from the
distal end of the hypotube. Due to the continuously variable
flexural strength of the hypotube in the mentioned end portion,
buckling sites will be avoided.
[0064] In alternative embodiments, instead of a helical line-shaped
notch 163, a plurality of notches offset in the axial direction may
also be provided on the stiffening element. Each of the notches can
extend over a partial circumference of the hypotube, with the
flexural strength depending on the axial distance between the
individual notches. A number of embodiments of the invention have
been described. Nevertheless, it will be understood that various
modifications may be made without departing from the scope of the
invention. Accordingly, other embodiments are within the scope of
the following claims.
* * * * *