U.S. patent application number 11/698248 was filed with the patent office on 2007-09-06 for deflection control catheters, support catheters and methods of use.
Invention is credited to Jason Galdonik, Mark W.I. Webster.
Application Number | 20070208302 11/698248 |
Document ID | / |
Family ID | 38327896 |
Filed Date | 2007-09-06 |
United States Patent
Application |
20070208302 |
Kind Code |
A1 |
Webster; Mark W.I. ; et
al. |
September 6, 2007 |
Deflection control catheters, support catheters and methods of
use
Abstract
A deflection and support catheter provided for improved
manipulation of elongated medical devices used during percutaneous
procedures in difficult to reach situations. In particular, the
deflection and support catheters can facilitate placement of
guidewires, guide catheters, and intervention devices such as
angioplasty balloons and stent delivery devices.
Inventors: |
Webster; Mark W.I.; (Mt.
Eden, NZ) ; Galdonik; Jason; (Hanover, MN) |
Correspondence
Address: |
DARDI & ASSOCIATES, PLLC
220 S. 6TH ST.
SUITE 2000, U.S. BANK PLAZA
MINNEAPOLIS
MN
55402
US
|
Family ID: |
38327896 |
Appl. No.: |
11/698248 |
Filed: |
January 25, 2007 |
Related U.S. Patent Documents
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
|
|
60762304 |
Jan 26, 2006 |
|
|
|
Current U.S.
Class: |
604/103.04 |
Current CPC
Class: |
A61M 25/01 20130101;
A61M 25/0041 20130101; A61M 2025/0183 20130101; A61F 2/95 20130101;
A61M 25/104 20130101; A61M 25/0023 20130101 |
Class at
Publication: |
604/103.04 |
International
Class: |
A61M 29/00 20060101
A61M029/00; A61M 31/00 20060101 A61M031/00; A61M 37/00 20060101
A61M037/00 |
Claims
1. A catheter comprising a proximal segment and a rapid exchange
segment connected at or near the distal end of the proximal
segment, the rapid exchange segment comprising a tubular element
with a lumen having a slit structure and sufficient rigidity to
track over a cylindrical object within the lumen by pushing from
the proximal end of the proximal segment.
2. The catheter of claim 1 wherein the proximal segment comprises a
rod.
3. The catheter of claim 2 wherein the rod is solid.
4. The catheter of claim 1 wherein the slit comprises overlapping
lips.
5. The catheter of claim 1 wherein the slit has a spiral
configuration.
6. The catheter of claim 1 wherein the rapid exchange segment
further comprises an overtube that slides over the tubular element
with the slit structure.
7. The catheter of claim 1 wherein the tubular element comprises a
radiopaque marker band.
8. The catheter of claim 1 wherein the tubular element comprises a
radiopaque-loaded polymer.
9. A medical delivery tool for elongated medical devices, the tool
comprising a flexible rod and a tubular element operably connected
to the rod wherein the tubular element has a distal opening, a
proximal opening and an open lumen connecting the distal opening
and the proximal opening such that the tubular element forms a
rapid exchange element to fit over an elongated medical device,
wherein the tubular element has a side port.
10. The medical delivery tool of claim 9 wherein the side port has
an elongated shape with a length along the longitudinal direction
of the catheter that is at least about 2 times the average diameter
of the guide lumen.
11. The medical delivery tool of claim 9 wherein the tubular
element has a durometer value of at least about 60 D at the side
guide port.
12. The medical delivery tool of claim 9 wherein the tubular
element has a slit.
13. The medical delivery tool of claim 9 wherein the tubular
element is curved.
14. A method for the delivery of an elongated medical device into a
vessel within a vascular network, the method comprising loading a
rapid exchange segment of a delivery tool onto the elongated
medical device and using the delivery tool to provide support for
the placement of the elongated medical device into the vessel
wherein the rapid exchange segment comprises a slit that provides
for the loading of the rapid exchange segment.
15. The method of claim 14, wherein the elongated medical device
comprise a balloon or a stent delivery structure.
16. A method for the delivery of a guidewire into a vessel within a
vascular network, the method comprising extending a curve tip of
the guidewire through a side port of a deflection catheter into the
vessel wherein the side port is positioned at the opening into the
vessel.
17. The method of claim 16 wherein the vessel is a coronary
artery.
18. A catheter comprising a proximal section, and a rapid exchange
segment operably connected to the proximal section, the rapid
exchange segment comprising a tubular element having a guide lumen,
a tip, a distal guide port and a side guide port, the tubular
element having a curve in the tip.
19. A guidewire delivery system comprising a guidewire having a
curved tip and a deflection catheter comprising a proximal section
and a rapid exchange segment operably connected to the proximal
section, the rapid exchange segment comprising a tubular element
comprising a guide lumen, a distal guide port at the distal end of
the guide lumen and a proximal guide port.
20. The guidewire delivery system of claim 19 wherein the rapid
exchange segment comprises a side guide port.
21. The guidewire delivery system of claim 19 wherein the rapid
exchange segment has a bent tip.
22. The guidewire delivery system of claim 19 wherein the rapid
exchange segment is curved.
23. The guidewire delivery system of claim 19 wherein the rapid
exchange segment has a plurality of curves.
24. The guidewire delivery system of claim 19 wherein the tubular
element comprises a proximal tubular segment, a distal tubular
segment and a non-tubular connection element connecting the
proximal tubular segment and the distal tubular segment, wherein
the side port is formed by the opening at the non-tubular
connection element.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to copending provisional
patent application Ser. No. 60/762,304 filed on Jan. 26, 2006 to
Webster et al., entitled "Deflection Control Catheter and Related
Method of Use," incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention relates to catheters to facilitate the
delivery of guidewires, guide catheters or other interventional
devices within a branched vascular network. The invention further
relates to methods for the delivery of guidewires, guide catheters
or other interventional devices along branched vessels in a
body.
BACKGROUND OF THE INVENTION
[0003] Percutaneous vascular procedures are performed in many
vessels in the body, including, for example, the coronary arteries,
saphenous vein grafts, carotid arteries, cerebral vessels, and
peripheral vessels. These procedures generally require the
physician to gain access to the target vessel with a guiding
catheter or sheath and track a guidewire into the vessel past a
lesion or other location for the performance of a treatment
procedure. One common complication of percutaneous procedures is
the inability to gain access to a vessel and thus to properly
position the interventional devices past the target position.
Anatomical variations, such as lesion size and morphology, vessel
tortuosity, and vessel take off angle contribute to these
complications. Additional factors, such as poor guide support, can
further lead to crossing issues. These complications can be
compounded when the patient has previously received a stent, when
the target lesion is located at a bifurcation, or when the patient
has a chronic total occlusion where the vessel is completely or
almost completely blocked.
SUMMARY OF THE INVENTION
[0004] In a first aspect, the invention pertains to a catheter
comprising a proximal segment and a rapid exchange segment
connected at or near the distal end of the proximal segment. The
rapid exchange segment comprises a tubular element with a lumen
having a slit structure and sufficient rigidity to track over a
cylindrical object within the lumen by pushing from the proximal
end of the proximal segment.
[0005] In a further aspect, the invention pertains to a medical
delivery tool for elongated medical devices. The tool comprises a
flexible rod and a tubular element operably connected to the rod.
The tubular element has a distal opening, a proximal opening and an
open lumen connecting the distal opening and the proximal opening
such that the tubular element forms a rapid exchange element to fit
over an elongated medical device. In some embodiments, the tubular
element has a side port.
[0006] In another aspect, the invention pertains to a method for
the delivery of an elongated medical device into a vessel within a
vascular network. The method comprises loading a rapid exchange
segment of a delivery tool onto the elongated medical device and
using the delivery tool to provide support for the placement of the
elongated medical device into the vessel. The rapid exchange
segment generally comprises a slit that provides for the loading of
the rapid exchange segment.
[0007] In other aspects, the invention pertains to a method for the
delivery of a guidewire into a vessel within a vascular network.
The method comprises extending a curve tip of the guidewire through
a side port of a deflection catheter into the vessel in which the
side port is positioned at the opening into the vessel.
[0008] Moreover, the invention pertains to a catheter comprising a
proximal section, and a rapid exchange segment operably connected
to the proximal section. The rapid exchange segment comprises a
tubular element having a guide lumen, a tip, a distal guide port
and a side guide port, and the tubular element has a curve in the
tip.
[0009] Furthermore, the invention pertains to a guidewire delivery
system comprising a guidewire having a curved tip and a deflection
catheter comprising a proximal section and a rapid exchange segment
operably connected to the proximal section. The rapid exchange
segment comprising a tubular element comprising a guide lumen, a
distal guide port at the distal end of the guide lumen and a
proximal guide port.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a fragmentary side view of a medical instrument
delivery system with a deflection/support catheter and an elongated
medical device.
[0011] FIG. 2 is a fragmentary side view of a medical instrument
delivery system with a rapid exchange deflection/support catheter
and an elongated medical device.
[0012] FIG. 3 is a fragmentary side view of an embodiment of a
rapid exchange deflection and support catheter riding on a guide
wire.
[0013] FIG. 4 is an expanded sectional view of the tip of the
deflection and support catheter and guidewire of FIG. 4 with the
section taken through the center of the catheter and guidewire.
[0014] FIG. 5 is an expanded sectional view of the tip of the
deflection catheter as shown in FIG. 4 with the tip of the
guidewire extending from a side port of the catheter.
[0015] FIG. 6 is a fragmentary perspective view of an embodiment of
a tip of a deflection and support catheter having a radiopaque
marker band distal to a side port.
[0016] FIG. 7 is a fragmentary perspective view of an embodiment of
a tip of a deflection and support catheter having a
non-circumferential radiopaque marker.
[0017] FIG. 8 is a fragmentary side view of an embodiment of a tip
of a deflection and support catheter having a radiopaque marker
below a side port.
[0018] FIG. 9 is a fragmentary perspective view of a rapid exchange
segment of a deflection and support catheter with a wire connecting
a distal tubular portion and a proximal tubular portion.
[0019] FIG. 10 is a fragmentary perspective view of a deflection
and support catheter having a rapid exchange segment with a slit
clipped onto an elongated medical device.
[0020] FIG. 11 is a side view of a deflection and support catheter
with a curved tip and a side port along a curved portion.
[0021] FIG. 12 is a side view of an alternative embodiment of a
deflection and support catheter with a curved tip and a side port
along a curved portion.
[0022] FIG. 13 is a side view of an embodiment of a deflection and
support catheter used with two guidewires with hidden structure of
the guidewires shown in phantom lines.
[0023] FIG. 14 is a fragmentary perspective side view of a rapid
exchange deflection and support catheter having a sharply bent
tip.
[0024] FIG. 15 is a fragmentary side view of the catheter of FIG.
14 engaging an elongated medical device.
[0025] FIG. 16 is a fragmentary side view of the catheter of FIG.
14 engaging an elongated medical device with its tip slightly
extending from the bent tip of the deflection and support
catheter.
[0026] FIG. 17 is a fragmentary side perspective view of a rapid
exchange deflection and support catheter riding over a medical
device with a highly bent tip.
[0027] FIG. 18 is a fragmentary side perspective view of the
catheter of FIG. 17 deflecting the medical device to a straighter
orientation for placement into a branch vessel.
[0028] FIG. 19A is a side view of a rapid exchange support
catheter.
[0029] FIG. 19B is a side view of a rapid exchange catheter with a
spiral slit.
[0030] FIG. 19C is a side view of a rapid exchange catheter with a
corkscrew slit.
[0031] FIG. 19D is a side view of a rapid exchange catheter with an
overtube.
[0032] FIG. 20A is a sectional view of an embodiment of the slit
rapid exchange segment of the catheter of FIG. 19.
[0033] FIG. 20B is a sectional view of an alternative embodiment of
the slit rapid exchange segment of the catheter of FIG. 19.
[0034] FIG. 21 is a fragmentary schematic view of a deflection
catheter riding over a medical device within a blood vessel.
[0035] FIG. 22 is a fragmentary schematic view of the deflection
catheter in the blood vessels as shown in FIG. 21 with the medical
device extending from a side port of the deflection and support
catheter.
[0036] FIG. 23 is a fragmentary schematic view of a deflection and
support catheter facilitating deployment of a medical device into a
renal artery.
[0037] FIG. 24 is a fragmentary schematic view of a deflection and
support catheter facilitating deployment of a medical device into a
coronary artery.
[0038] FIG. 25 is a fragmentary schematic view of an elongated
treatment structure within a blood vessel proximal to a lesion.
[0039] FIG. 26 is a fragmentary schematic view of the treatment
structure of FIG. 25 at he lesion following placement facilitated
with a support catheter.
DETAILED DESCRIPTION OF THE INVENTION
[0040] A deflection and support catheter as described herein
provides assistance to direct an elongate member within a blood
vessel during a percutaneous procedure into a difficult to reach
branch vessel. The deflection and support catheter can provide both
direction and support for entering into a difficult branch vessel
to navigate. In some embodiments, the deflection and support
catheter has a side port at a stiffened section to provide support
while the elongate member is directed through the side port into a
difficult to reach vessel. In appropriate embodiments, once the
side port is properly positioned, the curved tip of the elongate
member, such as a guidewire, facilitates the entry of the elongate
member out from the side port into the difficult to reach vessel.
With the support from a deflection and support catheter, the
physician can manipulate a guidewire past difficult to reach
positions in the branch vessel, such as past thrombus accumulated
at or near the vessel opening. Once the guidewire is in position,
the deflection and support catheter can be removed, and the
guidewire can be used to guide treatment structures, such as
angioplasty balloons and stents into the branch vessel. In other
embodiments, support and increased manipulation can be provided for
the guiding catheter or sheath with a deflection and support
catheter that similarly provides support for the distal end of a
guide catheter. Interaction between the curve of the guiding
catheter and the deflection and support catheter can aid in
steering and push. In this embodiment, the support catheter
generally has a rapid exchange segment that can clip over a guide
catheter. In a further embodiment, the deflection and support
catheter can be configured to ride over the shaft of an
interventional device such as a balloon or stent system. The
deflection and support catheter can provide increased support to
the distal segment of the interventional device that extends out
the distal end of the guiding catheter or sheath.
[0041] The deflection catheters described herein are generally
useful for the placement of guidewires or catheters in difficult to
reach vessels within the body of a patient, generally a human,
although the device can be used in other mammals. Similarly, the
deflection and support catheters are useful to facilitate the
deployment of guide catheters. Once the guidewire/guide
catheter/interventional device is placed at the desired location,
the deflection/support catheter is generally removed. In some
embodiments, the treatment structure or medical instrument is
placed at or past a lesion, which can be thrombus within in the
vessel.
[0042] The deflection and support catheter can have an over the
wire or rapid exchange configuration. In a rapid exchange
configuration, the elongate member extends within only a portion of
the catheter. The catheter generally has a guide port at its distal
tip. For rapid exchange embodiments, a rapid exchange guide port is
located to define a guide lumen extending from the rapid exchange
guide port to the distal port. The side port is located at an
appropriate position between the rapid exchange port and the distal
port. For embodiments that support and deflect other interventional
devices down difficult vasculature, the catheter has an overall
length to reach the target vessel from an appropriate insertion
point into the patient. For embodiments that support and deflect
other interventional devices, the catheter has an overall length to
reach the distal end of the interventional device.
[0043] In the rapid exchange configuration, the proximal portion of
the catheter extending in a proximal direction from the rapid
exchange port can be solid or tubular while providing a desired
degree of strength and flexibility since this section of catheter
only provides a mechanical function. In particular, the proximal
portion of the catheter can have a rod structure, a tubular
structure or other similar elongated form, with a flat, circular or
other appropriate cross section shape. The proximal section is used
only advance, withdraw and steer the rapid exchange segment within
the vessel from a section that is exterior to the patient. Thus,
this proximal segment should be stiff enough to push the rapid
exchange segment, and it should transmit torque for steering.
However, this proximal segment generally does not need an open
lumen or an outer surface suitable for the passage of instruments.
Also, it is advantageous for this segment to be of low profile.
[0044] In some embodiments, the deflection and support catheter has
a side port that is configured to facilitate the guiding of an
elongate member, such as a guidewire, out from the side port. The
side-guide port should be configured to allow for relatively easy
passage of a tip, generally a curved, tip of a guidewire to exit
the side port. For some embodiments, the widest diameter across the
port opening in some embodiments is at least 1.5 times the size of
the guidewire diameter and in other embodiments at least twice the
size of the guidewire diameter. The guide catheter can then support
the movement of the guidewire into a branch vessel even past an
occlusion while not making the task of the health care provider
excessively difficult. Generally, the side guide port does not have
a tubular projection so that there is no extraneous structure to
snag while moving the structure within a vessel. However, the side
port can be reinforced. In general, there is no projection of a
millimeter or greater from the side port relative to the surface of
the catheter.
[0045] In some embodiments, the deflection and support catheter has
curves at its tip for either an over the wire or rapid exchange
configuration. The curve can assist with placement of the side port
adjacent to an opening into a side branch vessel. The catheter can
have one or more curves along the length. It can be advantageous to
have two, three or more curves.
[0046] To provide additional support and to reduce or eliminate
kinking, it can be desirous to have a stiffened section at or near
the side port. Thus, the section surrounding the side port can be
stiffer than proximal and distal segments. Alternatively or
additionally, the section around the port can be stiff relative to
other sections of the catheter. The stiffness can be provided by
coating or embedding a wire or reinforcement at the appropriate
section and/or by using a different material welded or otherwise
connected to adjacent material. Furthermore, the side port section
can be constructed with one or more radiopaque bands that aid in
visualization and also provide increased stiffness. In some
embodiments, the stiffened section has a stiff measured with a
Durometer value of at least about 60 D.
[0047] In alternative embodiments, the deflection and support
catheter has a bent tip with appropriate stiffness so that a
guidewire or catheter extending outward from the tip can hold the
tip straight if extending sufficient from the tip, or the tip can
bend if the guidewire/catheter is extending only a short distance
from the tip. This embodiment provides an alternative to
embodiments with a side port.
[0048] To use the deflection and support catheter for delivery of a
guidewire into a branch vessel, the guidewire is directed into the
main vessel past the branch point. The deflection catheter can be
delivered over the guidewire while the guidewire is being delivered
or after the guidewire is in place. Then, the deflection catheter
is positioned with the side port adjacent the opening into the
branch vessel. Placement can be facilitated using radiopaque
markers on the deflection catheter or through visualization of
radiopaque material forming at least along a portion of the
deflection catheter, along with visualization dye in the vessel if
desired. Once the deflection catheter is in place, the guidewire
can be retracted so that its tip can exit through the side port.
With the support of the deflection catheter the guidewire generally
can be positioned past a lesion at or near the opening of the
branch vessel. Similarly, the support of the deflection catheter
can be used to reach into sharp bending branch vessels that are
otherwise difficult or impossible to reach. Once the guidewire is
in place, the deflection catheter can be removed. Thus, the
deflection catheter provides for the performance of procedures that
would not be otherwise possible.
[0049] In an alternative embodiment, the support catheter is used
to support another interventional device such as a balloon or stent
deploying instrument. This embodiment is referred to as a support
catheter. The support catheter generally has a rapid exchange
configuration. The tubular element of the support catheter has an
inner lumen sufficiently large for the passage of a guide catheter
of a selected diameter. A proximal section extends proximally from
the rapid exchange segment. This proximal section should have
enough stiffness to advance and withdraw the support catheter onto
and off from the guide catheter. The rapid exchange segment has a
slit structure that provides for loading and unloading the rapid
exchange segment onto and off from the guide catheter or
interventional device since the guide catheter or other
interventional device generally has handles and other structures
attached to its proximal end that makes it difficult or impossible
to advance the support catheter over the end of the guide catheter.
A slit refers broadly to any structure that provide for opening of
the generally cylindrical lumen to extend the rapid exchange
segment around the guide catheter. For example, the slit can have
overlapping portions, locking portions or the like, and some
representative embodiments are described further below.
[0050] Support catheter can be placed over the guide catheter or
other elongated interventional device for placement into a vessel.
The support catheter can be inserted into the patient if the health
care professional is having difficulty placing a guide catheter at
a desired location. The support catheter can provide additional
support at the distal end of the guide catheter to facilitate
placement of the guide catheter. Once the guide catheter is in
place, the support catheter can be removed.
[0051] The advantages of the deflection catheter and support
catheter can be further elucidated from the specific embodiments
described in the following.
Deflection/Support Catheter Structure
[0052] The deflection/support catheter has a distal port as well as
a side port and/or a proximal rapid exchange port. In embodiments
of particular interest, the catheter has a rapid exchange segment
with a rapid exchange port with the rapid exchange segment designed
to ride over a medical device during a percutaneous procedure. In
some embodiments, the rapid exchange segment can have a slit to
provide easier placement over the medical device for loading. In
additional or alternative embodiments, the deflection and support
catheter has a curved tip and/or a curved distal portion. A side
port, if present, can be configured to provide exit of the tip of
the elongated medical device directed with the deflection/support
catheter. The deflection/support catheter can be formed from a
radiopaque material and/or can have one or more radiopaque marker
bands to facilitate proper positioning in a patient.
[0053] A medical device delivery system comprises an elongated
medical device and a deflection and support catheter that is
designed to ride over the elongated medical device in an over the
wire or rapid exchange configuration. Referring to FIG. 1, medical
device delivery system 100 comprises an elongated medical device
102 and a medical delivery tool 104, e.g., a deflection
catheter/support catheter. The elongated medical device 102 can be
a guidewire, guide catheter, balloon catheter, stent delivery
catheter or other percutaneous medical instruments, such as those
well known in the art. A shown in FIG. 1, elongated medical device
102 has a bent tip 106. Guidewires as used herein can have a solid
structure or an internal structures such as a hollow lumen or a
core wire or the like. As shown in FIG. 1, medical delivery tool
104 has an optional side port 108 and an optional handle 110.
[0054] Percutaneous tools with rapid exchange, or monorail,
segments can be desirable due to their ease of loading. Referring
to FIG. 2, Medical device delivery system 116 comprises an
elongated medical device 118 and medical delivery tool 120.
Elongated medical device 118 can be the same medical devices
described with respect to elongated medical device 102. Medical
delivery tool 120 has a rapid exchange segment 122 and a proximal
extension 124. Rapid exchange segment 122 comprises a distal port
126 and a proximal port 128 that provide for an elongated medical
device to pass within the rapid exchange segment. As shown in FIG.
2, rapid exchange segment 122 has an optional side port 130.
Proximal extension 124 comprises an elongated element 132 and an
optional handle 134. Elongated element 132 can comprise a tubular
element, a solid rod or other elongated segment. A solid, flexible
rod or wire is convenient as having a smaller diameter than other
structures for selected mechanical properties, and a smaller
diameter provides for less blockage of the vessels and passage
through smaller guide catheters during use. During use elongated
element 132 connects rapid exchange segment 122 within the patient
with the exterior of the patient.
[0055] A particular embodiment of the medical delivery tool as a
rapid exchange deflection/support catheter is shown in FIG. 3.
Deflection and support catheter 150 can be used to deflect a
guidewire 152 into a branch vessel in a patient. Catheter 150
comprises rapid exchange segment 154 with side port 156, rod 158
and handle 160. In this embodiment, rapid exchange segment 154 has
a radiopaque marker band 162. For conventional guidewires, rapid
exchange segment can have a 21/2 French diameter. As described
further below, rapid exchange segment 154 can be formed from a
polymer tube optionally with braided or wound metal wire embedded
within the polymer.
[0056] An expanded, fragmentary sectional view of rapid exchange
segment 154 is shown in FIG. 4. Side port 156 should have a size
and shape to facilitate exit of the tip of guidewire 152 out
through side port 156. Thus, in some embodiments, the opening of
side port 156 has a length along the longitudinal direction of the
segment of at least about twice the diameter of guidewire 152, and
at least a portion of rapid exchange segment has a stiffness
corresponding with a durometer value of 60 D to support guidewire
152 as it is pushed through side port 156 possibly into a
significantly blocked branch vessel. As shown in the particular
embodiment of FIG. 4, the side port or window has a longitudinal
dimension, L, of about 8 mm and a distal extension, D, of about 10
mm, although other dimensions are suitable as desired.
[0057] Referring to FIG. 6, rapid exchange segment 154 is shown
with a single marker band 170 having a cylindrical configuration at
the distal end of side port 156. Referring to FIG. 6, rapid
exchange segment 154 has a non-cylindrical marker band 170 that
does not extend around the entire circumference of the rapid
exchange segment. The non-circumferential marker may make it easier
to align side port 156 during use. Referring to FIG. 8, rapid
exchange segment 154 has a marker section 174 placed below side
port 156 to again facilitate alignment of side port 156. In
alternative embodiments, a plurality of marker bands can be used
and/or the rapid exchange segment can be formed from a radiopaque
material.
[0058] An alternative embodiment of a rapid exchange segment for a
deflection and support catheter is shown in FIG. 9. Rapid exchange
segment 180 comprises a distal tubular element 182, a connecting
rod or wire 184 and proximal tubular element 186, which connects to
a rod or other elongated proximal element to extend out from the
patient. Connecting rod 184 connects distal tubular element 182
with proximal tubular element 186. During placement of the
deflection and support catheter, distal tubular element 182 and
proximal tubular element 186 ride over the medical device. The gap
between the proximal tubular element 186 and distal tubular element
182 can function as the side port for deflection of the guidewire
or other medical device. In alternative embodiments, a plurality of
wires can connect distal tubular element 182 and proximal tubular
element 186 with the gap between the tubular elements still
functioning as a side port.
[0059] Referring to FIG. 10, deflection and support catheter 190 is
shown clipped over guidewire or medical device 192. In this
embodiment, deflection and support catheter 190 comprises a rapid
exchange segment 194 and proximal rod 196. Rapid exchange segment
194 has a slit 198 extending along its length to facilitate
clipping onto the guidewire 192. Rapid exchange segment 194 further
has a distal port 200, a proximal port 202 and a side port 204.
Slit 198 extends form distal port 200 to proximal port 202. Rapid
exchange segment 194 has sufficient flexibility to open and close
over guidewire 192 while having sufficient rigidity to remain over
the guidewire as deflection catheter 190 is pushing into position.
Slit 198 can be formed with overlapping sections, sections that
meet, locking sections or other appropriate configurations that
provide the functional features.
[0060] The deflection and support catheter can have curves that
deflect the side port away from the axis of the distal and proximal
ports. Two embodiments with curved rapid exchange segments are
shown in FIGS. 11 and 12. Referring to FIG. 11, deflection and
support catheter 210 comprises rapid exchange segment 212 and
proximal rod 214. Rapid exchange segment 212 has a distal segment
216 with a distal port 218, proximal segment 220 with a proximal
port 222, and a curved segment 224 between distal segment 212 and
proximal segment 220. Side port 226 is located at the center of
curved segment 224 where the curved segment in its natural shape is
deflected furthest from the axis connecting distal port 218 with
proximal port 222. In this embodiment, rapid exchange segment 212
has a first radiopaque marker band 228 near distal port 218 and a
second radiopaque marker band 230 near the distal edge of side port
226. In some embodiments, the side port comprises a cut out of a
portion of the tubular element in which the cut out has a length
along the axis of the tubular element from about 1 to about 4
millimeters and a minimum circumference along the port of 1/3 of
the average circumference around the tubular element away from the
side port.
[0061] Referring to FIG. 12, deflection and support catheter 240
comprises rapid exchange segment 242 and proximal rod 244. Rapid
exchange segment 242 has a distal segment 246 with a distal port
248, proximal segment 250 with a proximal port 252, and a curved
segment 254. Side port 256 is located the outside proximal edge of
curved segment 254 relative to the position of the curved segment
in its natural shape that is deflected furthest from the axis
connecting distal port 248 with proximal port 252. In this
embodiment, rapid exchange segment 242 has a first radiopaque
marker band 258 near distal port 248 and a second radiopaque marker
band 260 near the distal edge of side port 256.
[0062] A two wire embodiment is depicted in FIG. 13. Referring to
FIG. 13, deflection catheter 270 is interfaced with first guidewire
272 and second guidewire 274. Guidewires 272, 274 can be
substituted for other appropriate elongated medical devices.
Deflection and support catheter 270 comprises a proximal extension
276 and rapid exchange segment 278. Rapid exchange segment 278
comprises a distal port 280, a proximal port 282 and a side port
284. In this embodiment, rapid exchange segment 278 has a curve,
and side port 284 is located at the maximum deflection of the
curve, although other placements of the side port can be used as
desired. Generally, side port 284 is large enough for the passage
of both guidewires 272, 274. First guidewire 272 and deflection and
support catheter 270 can be advanced together over second guidewire
274. Once side port 284 is in position, deflection and support
catheter 270 can be held in place while first guidewire 272 is
advanced out from side port 284 into a branch vessel. Then, second
guidewire 274 and deflection catheter 270 can be removed from the
patient with first guidewire 272 at its desired position.
[0063] A deflection and support catheter with a distal bent tip is
shown in FIG. 14. Referring to FIG. 14, deflection and support
catheter 300 has a proximal extension 302, such as a proximal rod,
and a rapid exchange segment 304. Rapid exchange segment 304 has a
proximal port 306 and a bent tip 308 with a distal port 310. In
some embodiments, bent tip 308 in its unstressed position can have
an angle of at least about 35 degrees and in some embodiments at
least about 45 degrees relative to the natural direction of the
remaining portions of rapid exchange segment 304. Referring to FIG.
15, guidewire 316 or other elongated medical device is extending
through rapid exchange segment 304 and out from distal port 310. A
sufficient length of guidewire 316 extends from distal port 310 so
that bent tip 308 flexes to a straighter configuration if any
forces tend to hold guidewire 316 in a relatively straight
position, such as would be the case in a blood vessel. Referring to
FIG. 16, as guidewire 316 is moved in a proximal direction relative
to deflection catheter 300, bent tip 308 can resume its natural
bent configuration with only guidewire tip 318 extending from
distal port 310. If distal port 310 is positioned at a branch
vessel, guidewire tip 318 can be advanced into the branch vessel
from distal port 310.
[0064] Another embodiment of a deflection and support catheter is
shown in FIGS. 17 and 18 in which a side port is not used to
deflect the medical device. Referring to FIG. 17, deflection and
support catheter 330 comprises a proximal extension 332 and rapid
exchange segment 334 having a distal port 336 and a proximal port
338. As shown in FIGS. 17 and 18, rapid exchange segment 334 is
straight and lacks a side port, although in alternative
embodiments, the rapid exchange segment can have a side port that
is not used and may be curved. Referring to FIG. 17, rapid exchange
segment 334 is riding over medical device 340, which can be a guide
wire, microcatheter or other elongated medical device. For
deployment, medical device 340 has a sharply bent tip portion 342.
As shown in FIG. 18, as deflection and support catheter 330 is
advanced near the distal end of medical device 340, rapid exchange
segment 334 deflects bent tip portion 342 of medical device 340 to
a less bent configuration that provides for placement into a branch
vessel.
[0065] An embodiment of a support catheter is shown in FIG. 19A.
Support catheter 350 comprises a proximal handle 352, a connecting
rod 354 and rapid exchange segment 356 with the connecting rod 354
connecting handle 352 with rapid exchange segment 356. Handle 352
can be formed form any convenient to grip material that is suitable
for sterile medical devices. Rapid exchange segment 356 comprises a
tubular element 358 with a slit 360 and a gentle curved tip 362.
Two suitable, representative cross sections for tubular element 358
with slit 360 are shown in FIGS. 20A and 20B. As shown in FIG. 20A,
two blunt edges meet at slit 360. As shown in FIG. 20B, two lips
370, 372 overlap at slit 360. Also, the edges of the slit can
interlock, such as with a keyed configuration, for example, as used
with a locking plastic sandwich bag, or the like
[0066] Referring to FIG. 19B, rapid exchange segment 374 has a
spiral shaped slit 376 that provides for easy mounting onto a
medical device but increased resistance to accidental
disengagement. The spiral shaped slit can be exaggerated further to
form a cork screw rapid exchange segment, as shown in FIG. 19C. As
shown in FIG. 19C, rapid exchange segment 378 has an exaggerated
spiral slit 380. Other configurations of the slit structure can be
used to provide appropriate ability to expand slit 360 to place
rapid exchange segment over a catheter or other elongated medical
device while providing after placement over the medical device
sufficient rigidity to advance rapid exchange segment 356 over the
medical device without any significant chance of disengaging from
the medical device inadvertently. Referring to FIG. 19D, support
catheter 382 has a proximal push section 382, a rapid exchange
section 384 with a slit 386 and an overtube 388. Overtube 388 can
be slid off of rapid exchange section 384 for loading and slid over
rapid exchange section 384 after loading to restrict disengagement.
Friction holds overtube 388 in place after loading.
[0067] In one specific embodiment for use in coronary arteries,
connecting rod 354 can have a length of roughly 95 centimeters, and
rapid exchange segment 356 can have a length of roughly 15
centimeters. Rapid exchange segment can have an inner diameter to
fit over a 4 to 4.5 French catheter and an outer diameter to just
fit within a 6 F guide catheter. For other applications, a person
of ordinary skill in the art can adjust the dimensions of the
device appropriately based on the teachings herein.
[0068] In general, the deflection/support catheter can be formed
from one or more biocompatible materials, including, for example,
metals, such as stainless steel or alloys, e.g., Nitinol.RTM., or
polymers such as polyether-amide block co-polymer (PEBAX.RTM.),
nylon (polyamides), polyolefins, polytetrafluoroethylene,
polyesters, polyurethanes, polycarbonates or other suitable
biocompatible polymers. Radiopacity can be achieved with the
addition of markers, such as platinum-iridium or platinum-tungsten
or through radio-pacifiers, such as barium sulfate, bismuth
trioxide, bismuth subcarbonate, powdered tungsten, powdered
tantalum or the like, added to a polymer resin. Generally,
different sections of deflection/aspiration catheter can be formed
from different materials from other sections, and sections of the
catheter can comprise a plurality of materials at different
locations and/or at a particular location. For example, a proximal
extended rod/wire can be formed from metal, such as stainless
steel. With respect to a rapid exchange segment, one material of
particular interest is a themoplastic polymer with embedded metal
wire. Suitable polymers include, for example, polyamides, i.e.,
nylons. The wire can be braided, coiled or otherwise placed over a
polymer tubing liner with some tension. A polymer jacket is then
placed over the top. Upon heating over the softening temperature of
the polymer and subsequent cooling, the wire becomes embedded
within the polymer. The liner and jacket can be the same or
different materials. Suitable wire for embedding in the polymer
includes, for example, flat stainless steel wire. The wire adds
additional mechanical strength while maintaining appropriate
amounts of flexibility.
[0069] The materials generally can be molded, extruded or the like,
for example, based on well known processing approaches in the
field. Materials can be joined by softening one material and
embedding the other material within the softened material, and/or
using mechanical reinforcements, clams, brackets or the like.
Medical grade materials are generally commercially available for
adaptation for forming the structures described herein. Curves can
be introduced to polymer material through softening the polymer and
hardening the polymer on a curved mandrel or the like.
Use of the Devices
[0070] In general, the deflection/support catheters can be used in
any reasonable vessels in a patient. However, the
deflection/support catheters are particularly useful for directing
medical instruments in a patient's blood vessels. In general, the
deflection/support catheters are intended to facilitate procedures
so that they are easier and faster than difficult procedures using
other instruments. Furthermore, the deflection/support catheters
are intended to facilitate procedures that otherwise could not be
completed since the medical instruments could not be positioned
appropriately.
[0071] A general application of a deflection and support catheter
is depicted in FIGS. 21 and 22. As shown in FIG. 21, deflection and
support catheter 400 has been deployed in a blood vessel 402 over a
guidewire 404 or other catheter or elongated medical instrument and
through a guide catheter 406. Deflection and support catheter 400
has a side port 408 and a distal port 410. As shown in FIG. 21,
guidewire 404 is extending from distal port 410, and side port 408
is positioned near the opening of branch vessel 412.
[0072] Referring to FIG. 22, guidewire 404 is shown extending
through side port 408 and into branch vessel 412. Distal tip 414 of
deflection and support catheter 400 extending distal from side port
408 helps to anchor the deflection and support catheter during the
procedure. During the transition from the configuration shown in
FIG. 21 to the configuration shown in FIG. 22, guidewire 404 is
pulled into distal tip 414 until the tip of guidewire 404 can exit
side port 408. Once guidewire 404 has exited side port 408, the
guidewire can be advanced into branch vessel 412 with support from
deflection and support catheter 400. Once the guidewire is within
the branch vessel, the deflection and support catheter can be
removed.
[0073] Referring to FIG. 23, a deflection and support catheter 420
is used to deploy a guide catheter 422 into renal artery 424.
Deflection and support catheter 420 is shown with a curved rapid
exchange segment 426, a proximal flexible rod 428, a distal port
430 and a side port 432. A shown in FIG. 23, the tip of guide
catheter 422 is shown exiting side port 432 at the opening into
renal artery 424 so that guide catheter 422 can be advanced into
renal artery 424 with support form deflection catheter 420.
[0074] Referring to FIG. 24, a deflection and support catheter 440
is used to deploy a guide catheter 442 into a coronary artery 444
from aorta 446. Deflection and support catheter 440 is shown with a
curved rapid exchange segment 448, a proximal flexible rod 450, a
distal port 452, a proximal port 454 and a side port 456. A shown
in FIG. 24, the tip of guide catheter 442 is shown exiting side
port 456 at the opening into coronary artery 444 so that guide
catheter 442 can be advanced into coronary artery 444 with support
form deflection/support catheter 440.
[0075] The use of a support catheter generally is depicted in FIGS.
25 and 26. Referring to FIG. 25, a treatment catheter 470 extends
out from guide catheter 472 into vessel 474 on guidewire 476.
Guidewire 476 extends past lesion 478, but it is difficult to
advance treatment structure 480 on treatment catheter 470 to lesion
478 due to the extent of blockage from lesion 478 and the bending
of vessel 474. Referring to FIG. 26, support catheter 490 has a
rapid exchange structure with a slit 492 such that support catheter
490 can be clipped onto treatment catheter 470. Support catheter
490 is advanced through a Tuohy-Borst valve or the like, through
the guide catheter to extend from guide catheter 472 into vessel
474. In some embodiments, support catheter 490 can be extended up
to 10 to 12 centimeters into the vessel, such as a coronary artery,
graft or the like. With additional support from support catheter
472, treatment structure 480 can be advanced to lesion 478 where a
balloon angioplasty, stent deployment and/or other treatment can be
performed. Once the lesion is crossed, support catheter 490 can be
removed. Suitable angioplasty balloons are described further, for
example in U.S. Pat. No. 6,132,824 to Hamlin, entitled "Multilayer
Catheter Balloon," incorporated herein by reference. Stent delivery
is described further, for example, in U.S. Pat. No. 6,610,069 to
Euteneuer et al., entitled "Catheter Support For Stent Delivery,"
incorporated herein by reference. Various stents and angioplasty
balloons are commercially available.
[0076] Based on a rough estimate, 10 to 20 percent of procedures
have significant difficulty reaching or crossing a lesion with a
treatment structure due to proximal vessel tortuosity,
calcification and/or the like. The approaches described herein
using a support catheter are more generally applicable and are
expected to have a greater degree of success relative to approaches
based on exchanging devices for a smaller balloon, changing the
guide catheter, using a buddy guidewire or the like.
[0077] The deflection/support catheters can be sterilized and
packaged for distribution using, for example, conventional
approaches. Radiation and or chemical sterilization can be used.
The packaged catheters can be distributed for use with other
medical devices for percutaneous procedures.
[0078] The embodiments above are intended to be illustrative and
not limiting. Additional embodiments are within the claims. In
addition, although the present invention has been described with
reference to particular embodiments, those skilled in the art will
recognize that changes can be made in form and detail without
departing from the spirit and scope of the invention. Any
incorporation by reference of documents above is limited such that
no subject matter is incorporated that is contrary to the explicit
disclosure herein.
* * * * *