U.S. patent application number 10/005852 was filed with the patent office on 2002-09-19 for low profile catheter valve and inflation adaptor.
Invention is credited to Bagaoisan, Celso J., Bleam, Jefferey C., Field, Jeffrey F., Kim, Isaac J., Leguidleguid, Roy, Marano-Ford, April A., Patel, Mukund, Tsai, George, Zadno-Azizi, Gholam-Reza.
Application Number | 20020133117 10/005852 |
Document ID | / |
Family ID | 27503579 |
Filed Date | 2002-09-19 |
United States Patent
Application |
20020133117 |
Kind Code |
A1 |
Zadno-Azizi, Gholam-Reza ;
et al. |
September 19, 2002 |
Low profile catheter valve and inflation adaptor
Abstract
Disclosed herein is a low profile catheter valve comprising a
movable sealer portion positioned within the inflation lumen of a
catheter. The sealer portion forms a fluid tight seal with the
inflation lumen by firmly contacting the entire circumference of a
section of the inflation lumen. The sealer portion may be
positioned proximally of a side-access inflation port on the
catheter, to establish an unrestricted fluid pathway between the
inflation port and an inflatable balloon on the distal end of the
catheter. As desired, the clinician may move the sealer portion to
a position distal of the inflation port, thereby preventing any
fluid from being introduced into or withdrawn from the balloon via
the inflation port. Also disclosed herein is an inflation adaptor
for moving the sealer portion within the catheter to establish or
close the fluid pathway between the inflation port and the
inflatable balloon.
Inventors: |
Zadno-Azizi, Gholam-Reza;
(Newark, CA) ; Marano-Ford, April A.; (Palo Alto,
CA) ; Bagaoisan, Celso J.; (Union City, CA) ;
Bleam, Jefferey C.; (Boulder Creek, CA) ; Kim, Isaac
J.; (San Jose, CA) ; Field, Jeffrey F.;
(Camarillo, CA) ; Leguidleguid, Roy; (Union City,
CA) ; Patel, Mukund; (San Jose, CA) ; Tsai,
George; (Sunnyvale, CA) |
Correspondence
Address: |
KNOBBE MARTENS OLSON & BEAR LLP
620 NEWPORT CENTER DRIVE
SIXTEENTH FLOOR
NEWPORT BEACH
CA
92660
US
|
Family ID: |
27503579 |
Appl. No.: |
10/005852 |
Filed: |
December 4, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10005852 |
Dec 4, 2001 |
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09410456 |
Oct 1, 1999 |
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6325777 |
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09410456 |
Oct 1, 1999 |
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08975723 |
Nov 20, 1997 |
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6050972 |
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08975723 |
Nov 20, 1997 |
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08812139 |
Mar 6, 1997 |
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08812139 |
Mar 6, 1997 |
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08650464 |
May 20, 1996 |
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Current U.S.
Class: |
604/99.04 |
Current CPC
Class: |
A61M 25/0075 20130101;
A61M 25/10185 20131105; A61M 25/0054 20130101; A61M 25/0026
20130101; A61M 2025/1079 20130101; A61M 2025/1052 20130101; A61M
2025/09008 20130101; A61M 25/104 20130101; A61M 2025/1015 20130101;
A61M 25/09 20130101; A61M 2025/0018 20130101; A61M 25/0009
20130101; A61M 2025/09175 20130101; A61M 2025/1093 20130101; A61M
25/09033 20130101; A61M 25/10 20130101 |
Class at
Publication: |
604/99.04 |
International
Class: |
A61M 029/00 |
Claims
What is claimed is:
1. An intravascular guidewire inflation system, comprising: a
hollow metallic body having distal and proximal portions, said body
having a central lumen formed therein with distal and proximal
ports in fluid communication with said lumen; an expandable member
mounted on said distal portion of said body and adapted to be in
fluid communication with said distal port of said central lumen,
such that fluid introduced through said proximal port will cause
actuation of said expandable member; a valve movably inserted with
respect to said proximal port of said body, said valve movable
between a first position to seal said central lumen to prevent
deactuation of said expandable member and a second position to
unseal said central lumen to allow actuation or deactuation of said
expandable member; and a valve adaptor which may be removably
mounted on said proximal portion of said body, said adaptor having
an auxiliary lumen adapted to be in fluid communication with said
proximal port of said central lumen and further adapted to receive
a fluid delivery device for selectively actuating or deactuating
said expandable member.
2. The guidewire inflation system of claim 1, wherein said metallic
body comprises nitinol.
3. The guidewire inflation system of claim 1, wherein said
expandable member comprises a balloon formed from an elastomeric
material selected from the group consisting of C-FLEX, silicones,
latex and polyurethanes.
4. The guidewire inflation system of claim 1, wherein said metallic
body has an outer diameter of from about 0.010 inches to about
0.032 inches.
5. The guidewire inflation system of claim 4, wherein said metallic
body has an outer diameter of from about 0.014 inches to about
0.018 inches.
6. A guidewire inflation system, comprising: a hollow metallic body
having distal and proximal portions, said body having a central
lumen formed therein with distal and proximal ports in fluid
communication with said central lumen; an inflatable member mounted
on said distal portion of said body in fluid communication with
said distal port of said central lumen, such that fluid introduced
through said proximal port will cause inflation of said inflatable
member; a valve movably inserted with respect to said proximal port
of said body, said valve movable between a first position to seal
said central lumen to prevent deflation of said inflatable member
and a second position to unseal said central lumen to allow
inflation or deflation of said inflatable member; and a valve
adaptor which may be removably mounted on said proximal portion of
said body, said adaptor having an auxiliary lumen adapted to be in
fluid communication with said proximal port of said central lumen
and further adapted to receive a fluid delivery device for
selectively inflating or deflating said inflatable device.
7. The guidewire inflation system of claim 6, wherein said metallic
body comprises nitinol.
8. The guidewire inflation system of claim 6, wherein said
inflatable member comprises a balloon formed from an elastomeric
material selected from the group consisting of C-FLEX, silicones,
latex and polyurethanes.
9. The guidewire inflation system of claim 6, wherein said metallic
body has an outer diameter of from about 0.010 inches to about
0.032 inches.
10. The guidewire inflation system of claim 6, wherein said
metallic body has an outer diameter of from about 0.014 inches to
about 0.018 inches.
11. The guidewire inflation system of claim 6, wherein said distal
portion of said hollow metallic body comprises a coil at the distal
tip of said body.
12. The guidewire inflation system of claim 11, wherein said
central lumen has a core wire inserted therein at a distal opening,
and said core wire extends distally from said distal opening within
said coil.
13. The guidewire inflation system of claim 6, wherein said valve
comprises a metallic rod slidably inserted into said central
lumen.
14. The guidewire inflation system of claim 13, wherein the
diameter of a first portion of said metallic rod is less than the
internal diameter of said central lumen and the diameter of a
second portion of said metallic rod is greater than the diameter of
said central lumen.
15. The guidewire inflation system of claim 14, wherein the
diameter of said second portion of said metallic rod is about 0.014
inches or less.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a continuation of application
Ser. No. 09/410,456, filed Oct. 1, 1999, now U.S. Pat. No.
6,325,777, which is a divisional of application Ser. No.
08/975,723, filed Nov. 20, 1997, now U.S. Pat. No. 6,050,972, which
is a continuation-in-part of application Ser. No. 08/812,139, filed
Mar. 6, 1997, abandoned, which is continuation-in-part of
application Ser. No. 08/650,464 filed on May 20, 1996, abandoned,
the entirety of each of which is hereby incorporated by
reference.
BACKGROUND OF THE INVENTION
[0002] The present invention generally relates to catheters, and in
particular, to a detachable inflation adaptor for a catheter having
a low profile valve which may be opened to permit inflation or
deflation of a catheter balloon, such as an occlusion balloon, and
which may be closed when it is desirable to maintain the catheter
balloon in an inflated state.
[0003] Guidewires are conventionally used to guide the insertion of
various medical instruments, such as catheters, to a desired
treatment location within a patient's vasculature. In a typical
procedure, the clinician forms an access point for the guidewire by
creating an opening in a peripheral blood vessel, such as the
femoral artery. The highly flexible guidewire is then introduced
through the opening into the peripheral blood vessel, and is then
advanced by the clinician through the patient's blood vessels until
the guidewire extends across the vessel segment to be treated.
Various treatment catheters, such as a balloon dilatation catheter
for a percutaneous transluminal coronary angioplasty, may then be
inserted over the guidewire and similarly advanced through
vasculature until they reach the treatment site.
[0004] In certain treatment procedures, it is desirable to
successively introduce and then remove a number of different
treatment catheters over a guidewire that has been placed in a
particular location. In other words, one treatment catheter is
"exchanged" for another over a single guidewire. Such an exchange
typically involves withdrawing the treatment catheter over the
guidewire until the treatment catheter is fully removed from the
patient and the portion of the guidewire which extends from the
patient. The guidewire is then available to act as a guide for a
different treatment catheter.
[0005] In emboli containment devices, which typically utilize two
occlusion balloons to form a chamber, it may be desirable to
exchange therapeutic catheters without deflating the occlusion
balloons. Further, it is sometimes advantageous to anchor the
guidewire during the exchange. As can be readily appreciated, the
withdrawal of treatment catheters over a placed guidewire may
result in the guidewire being displaced from its position. To
overcome this difficulty, the prior art has developed "anchorable"
guidewires, which generally feature some structure on their distal
ends to releasably secure the guidewire at a particular location in
the patient for the duration of the medical procedure. One such
anchorable guidewire is disclosed in U.S. Pat. No. 5,167,239 to
Cohen et al., which discloses a hollow guidewire with an inflation
lumen and an expandable balloon on its end. The Cohen guidewire is
positioned in the same manner as a conventional wire guidewire, but
once placed, its expandable balloon is inflated to contact the
surrounding vasculature, thereby preventing the guidewire from
being displaced.
[0006] Because a permanent inflation manifold, of the type used
with conventional catheters having an inflatable balloon, would
prevent other catheters from being inserted over the Cohen
guidewire, the Cohen device also includes a removable inflation
manifold, and a check valve to maintain the balloon in the inflated
state when the manifold is removed. The check valve apparatus used
by the Cohen device is relatively bulky, and is described as having
an outer diameter in its preferred embodiment of 0.0355 inches.
Consequently, any treatment catheter intended to be inserted over
the Cohen device must have an interior guidewire lumen larger than
the outer diameter of the Cohen valve, which for the preferred
embodiment, requires an interior lumen with a diameter of more than
0.0355 inches.
[0007] As is readily appreciated by those of skill in the art,
increasing the interior lumen size of a treatment catheter results
in an increase in the outer diameter of the treatment catheter. For
treatment procedures which take place in vasculature having a large
blood vessel diameter, such as iliac arteries, a treatment catheter
guidewire lumen of a size necessary to accommodate devices such as
those described by Cohen would have little or no affect on the
ability of the catheter to fit within the blood vessel. However,
many blood vessels where it is desirable to apply catheter
treatment are quite narrow. For example, the left coronary arteries
are blood vessels having diameters ranging from 2 to 4 mm, and are
susceptible to plaque. It would be desirable to use a catheter
exchange treatment procedure, such as angioplasty, to treat such
lesions, but the narrow diameter of the coronary vessels makes use
of anchorable guidewires having large valve diameters
impractical.
[0008] Consequently, there exists a need for a very low profile
catheter valve which can be used with a hollow guidewire.
Furthermore, there exists a need for a detachable inflation adaptor
which can be used with such low profile valves to open and close
them, and to apply inflation or deflation forces to the catheter
balloons.
SUMMARY OF THE INVENTION
[0009] The present invention provides a catheter valve which is
capable of very low profiles, and is especially advantageous for
use with anchorable guidewires, as well as therapeutic or occlusion
devices. By incorporating this into such devices, it is possible to
manufacture anchorable guidewires and occlusion device catheters
with outer diameters of 0.014 inches or smaller. Advantageously, by
utilizing this valve in these catheters, clinicians will be able to
use anchorable guidewires, therapeutic or occlusion device
catheters in much narrower blood vessels than in the past.
[0010] The present invention also provides for a detachable
inflation adaptor which can be used with catheters having these low
profile valves. The adaptor can be attached tot he catheter to open
the valve, and then apply inflation fluid to inflate the catheter
balloon. Following this, the valve may then be closed and the
adaptor removed, with the balloon remaining in its inflated state
and the catheter now able to function as an anchored guidewire.
When it is desired to deflate the balloon, the adaptor may be once
again attached to the catheter, the valve opened, and the inflation
fluid removed to deflate the balloon.
[0011] In one aspect of the present invention, there is provided a
valve which comprises a flexible elongate tubular body having a
proximal end and a distal end. The tubular body has a central lumen
extending between the proximal and distal ends. The central lumen
has an opening at the proximal end.
[0012] An expandable member, such as an inflatable balloon, is
positioned on the distal end of the tubular body. The expandable
member is in fluid communication with the central lumen. An access
opening is provided on the tubular body. The access opening is in
fluid communication with the central lumen to permit the expandable
member to be actuated by pressurizing the access opening. The
access opening may be the central lumen opening or a side-access
port positioned on the tubular body at a point proximal to the
distal end of the tubular body.
[0013] A sealing member is provided having a sealer portion which
seals against a surface of the tubular body. The sealing portion of
the sealing member is movable relative to the surface of the
tubular body between two positions. In the first position, the
sealer portion is positioned in contact with the tubular body
surface at a location which blocks the flow of fluid to or from the
expandable member through the access opening to maintain actuation
of the expandable member. In the second position, the sealer
portion is positioned at a location which permits the flow of fluid
to or from the expandable member through the access opening to
permit actuation or deactuation of the expandable member.
[0014] In one preferred embodiment, the sealing member has a
portion which extends from the proximal end of the tubular body,
and the application of a longitudinal force on the extending
portion results in movement of the sealer portion in the direction
of the applied force. In other embodiments, rotational forces may
be used to move the sealing member.
[0015] There is also preferably provided a force-increasing
structure which increases the longitudinal force which must be
applied to the extending portion to move the sealer portion.
[0016] The sealer portion is preferably formed of a polymeric
material, such as PEBAX (TM), silicone, C-FLEX(TM) or gels. The
sealer portion is capable of withstanding pressures up to ten
atmospheres and prevent substantially all fluid from passing to or
from the expandable member through the access opening when the
sealer portion is positioned distal to the access opening. The
sealer portion is also capable of undergoing 10 valve-opening and
closing cycles, and, at a pressure of ten atmospheres, still
prevent substantially all fluid from passing to or from the balloon
when the sealer portion is positioned distal to the access opening.
At least a portion of the sealing member is selected from the group
of metals consisting of nitinol, stainless steel, Elgiloy.theta. or
combinations thereof.
[0017] Advantageously, the outer diameter of the tubular body is
generally larger than the outer diameter of any portion of the
sealing member or sealer portion. In some embodiments, the outer
diameter of the tubular body is no greater than 0.038 inches,
preferably no greater than 0.020 inches, and more preferably no
greater than 0.014 inches. Other embodiments may have larger outer
diameters for the tubular body. The tubular body may also have
positive stops to prevent withdrawal of the sealing member from the
opening.
[0018] There is also preferably provided in combination with this
valve an inflation adaptor capable of receiving the valve. The
inflation adaptor provides a fluid-tight chamber for introduction
of a pressurized fluid to expand the expandable member.
[0019] In another aspect of the present invention, there is
provided an apparatus, comprising a hollow metallic guidewire
having a central lumen and a side-access port in fluid
communication with the lumen. An inflatable balloon is mounted on
the guidewire, the inflatable balloon being in fluid communication
with the central lumen, such that fluid introduced through the
side-access port can be used to inflate the balloon.
[0020] A valve is mounted to slide along a surface of the
guidewire, the valve movable between first and second positions,
one of the positions sealing the central lumen such that
substantially no fluid may pass to or from the inflatable balloon
by way of the side-access port.
[0021] Preferably, the hollow guidewire has an outer circumference
defining a first value, and the movable valve has a circumference
which is less than the first value. It is also preferred that the
hollow guidewire have an outer circumference of 0.12 inches or
less, more preferably 0.08 inches or less, and optimally 0.044
inches or less, and that the movable valve have a diameter not
substantially larger than that of the hollow guidewire, and the
valve seals against an interior surface of the hollow
guidewire.
[0022] In another aspect of the present invention there is provided
a low profile catheter valve which comprises a sealing member
capable of being movably inserted through a proximal opening on a
catheter into an inflation lumen of the catheter. The catheter has
a side-access inflation port and an inflatable balloon in fluid
communication with the side-access inflation port. A sealer portion
is on the sealing member, the sealer portion being capable of
forming a fluid tight seal with the entire circumference of a
section of the lumen, such that substantially all fluid may not
pass the sealer portion at normal balloon inflation pressures.
[0023] When the sealer portion is positioned within the lumen
proximally of the side-access inflation port, an unrestricted fluid
pathway is established between the side-access inflation port and
the balloon. When the sealer portion is positioned within the lumen
distally of the side-access inflation port, substantially all fluid
may not pass to or from the balloon through the side-access
inflation port at normal balloon inflation pressures.
[0024] In another aspect of the present invention, there is
provided a method of inflating a catheter balloon. The first step
of the method involves providing a tube having a proximal end and a
distal end. The proximal end of the tube has an inflation opening
to an inflation lumen and the distal end has an inflatable balloon
in fluid communication with the inflation lumen. A pressurized
inflation fluid is then introduced through the inflation opening to
inflate the balloon. The inflation opening may then be sealed by
moving a sealing member within the inflation lumen without reducing
the pressure of the pressurized fluid, wherein the step of sealing
is performed without substantial deflation of the inflated balloon.
Finally, the pressure of the pressurized fluid may be reduced after
completing the sealing step.
[0025] In another aspect of the present invention, there is
provided a low profile catheter valve for use with an inflation
adaptor. The valve comprises a sealing member capable of being
movably inserted through a proximal opening on a catheter into an
inflation lumen of the catheter. The catheter has an inflation
opening and an inflatable balloon in fluid communication with the
inflation opening. Indicia are present on the catheter and/or
sealing member, the position of the indicia being such that the
inflation opening is aligned with a fluid tight inflation chamber
of the inflation adaptor when the catheter and sealing member are
secured in the inflation adaptor.
[0026] A sealer portion is mounted on the sealing member. The
sealer portion is capable of forming a fluid tight seal with the
entire circumference of a section of the lumen, such that
substantially all fluid may not pass the sealer portion at normal
balloon inflation pressures. When the sealer portion is positioned
proximally of the inflation opening, an unrestricted fluid pathway
is established between the inflation opening and the balloon. When
the sealer portion is positioned distally of the inflation opening,
substantially all fluid may not pass to or from the balloon through
the side-access inflation port.
[0027] In another aspect of the present invention, there is
provided an inflation adaptor for introducing inflation fluid into
an inflation port of an elongate tube. The inflation adaptor
comprises a housing having first and second portions which interact
to releasably retain a section of the tube therein. The housing has
a chamber which receives the inflation port. An inflation inlet
configured to be connected to a source of inflation fluid that
supplies the fluid under pressure is positioned on the housing. The
housing also has a seal which releasably seals the portions of the
housing together, and provides a fluid pathway between the
inflation inlet and the inflation port, so that fluid may be
supplied to the inflation port under pressure. The seal is created
by alignment of a first and second gasket on the housing portions.
An actuator, mounted on the housing, drives a member within the
tube to control fluid flow through the catheter inflation port. The
actuator may control sliding panels which drive the tube members in
some embodiments. Preferably, there are indicia on the elongate
tube and housing which facilitate alignment of the catheter
inflation port and the housing chamber.
[0028] In another aspect of the present invention, there is
provided an inflation adaptor for introducing inflation fluid into
an inflation port of an elongate tube. The inflation adaptor
comprises a housing having first and second portions. The portions
of the housing are relatively movably mounted to receive a section
of the elongate tube which includes the inflation port. The housing
also has an inflation chamber and an inflation inlet for
introducing inflation fluid under pressure into the inflation
chamber. The inflation chamber releasably seals the inflation port
to the inflation inlet to form a fluid passage therebetween.
[0029] In another aspect of the present invention, there is
provided an inflation adaptor for introducing inflation fluid into
an inflation port of an elongate tube. The inflation adaptor
comprises a housing having first and second portions. The two
portions form a mouth for receiving a section of the tube which
includes the inflation port. The mouth forms an opening having a
height at least as great as the outer diameter of the tube such
that the section of tube is insertable into the mouth from its side
in a direction transverse to the longitudinal axis of the tube. The
housing also has an inflation chamber and an inflation inlet for
introducing inflation fluid under pressure into the inflation
chamber. The inflation chamber releasably seals the inflation port
to the inflation inlet to form a fluid passage there between.
[0030] In another aspect of the present invention, there is
provided an inflation adaptor for introducing inflation fluid into
an inflation port of an elongate tube. The tube has an inflatable
member mounted thereon and an inflation lumen between the inflation
port and the inflatable member. The adaptor has a housing
configured to seal over the tubular body to create a fluid tight
seal. An inflation inlet is on the housing, for establishing a
fluid pathway between the inflation inlet and the inflation port to
permit the inflatable member to be inflated. The housing is
detachable from the tube without deflating the inflated inflatable
member.
[0031] In another aspect of the present invention, there is
provided an inflation adaptor for introducing inflation fluid into
an inflation port of an elongate tube having an inflatable member
mounted thereon and an inflation lumen between the inflation port
and the inflatable member. The adaptor comprises a housing with an
upper portion and a lower portion. The housing is configured to
seal over the tube to create a fluid tight inflation chamber. The
housing also has an inflation inlet and establishes a fluid pathway
between the inflation inlet and the inflation port to permit the
inflatable member to be inflated. The housing is detachable from
the tube without deflating the inflated inflatable member.
[0032] A latch with a camming surface is on the housing, and is
adapted to secure the housing upper portion to the housing lower
portion. A cammed surface is on the housing upper, and is adapted
to receive the camming surface. With this structure, when a user
exerts a force on the latch to secure the upper portion to the
lower portion, the camming surface cooperates with the cammed
surface to provide a closing force on the upper and lower portions
which is greater than the force exerted by the user.
[0033] In one preferred embodiment, the upper portion has a first
gasket, and the lower portion has a second gasket, and the fluid
tight inflation chamber is established when the gaskets are brought
together and secured by the latch. Preferably, the upper portion
has a movable panel with the movement being controlled by an
actuator on the housing that is accessible to a clinician when the
adaptor is in use. There is also a lower movable panel on the lower
housing portion, which is capable of being moved in conjunction
with the upper portion movable panel when the fluid tight inflation
chamber is established.
[0034] In another prefered embodiment, a spring biased rod is
connected to the lower portion movable panel, the spring biased rod
defining the distance in at least one dimension that the upper
portion movable panel and lower portion movable panel may travel
when the fluid tight inflation chamber is established. The movable
panel are preferably movable for a distance of greater than 1 mm,
and more preferably for a distance of greater than 5 mm.
[0035] In another aspect of the present invention, there is
provided a low profile catheter valve sealing member. The sealing
member has an extension wire with a proximal end and a distal end.
The extension wire tapers at the distal end. A connecting hypotube
is attached to the extension wire proximal end. The connecting tube
has a tapering distal end. A plug mandrel wire is attached to the
hypotube distal end. A sealer portion is on the plug mandrel wire,
the sealer portion being capable of forming a fluid tight seal with
the entire circumference of a section of a catheter lumen.
[0036] In another aspect of the present invention, there is
provided a low profile catheter valve sealing member for a catheter
having a lumen with a first diameter. The sealing member has a
first region having a diameter greater than the first diameter, and
a tapering portion resulting in a second region with a diameter
less than the first diameter. The second region is slidably
inserted in the catheter lumen. A plug mandrel wire is connected to
the second region at the distal end of the second region, the plug
mandrel wire having a diameter smaller than the second region
diameter. A sealer portion is on the plug mandrel wire, the sealer
portion being capable of forming a fluid tight seal with the entire
circumference of a section of a catheter lumen.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] FIG. 1 is a side view of a catheter incorporating the low
profile valve of the present invention.
[0038] FIG. 2 is an enlarged view of the proximal portion of the
catheter of FIG. 1, showing an exterior view of the catheter
segment featuring the low profile valve of the present
invention.
[0039] FIG. 3A is a longitudinal cross-sectional view of the
catheter segment of FIG. 2, showing the low profile valve in the
open position.
[0040] FIG. 3B is a longitudinal cross-sectional view of the
catheter segment of FIG. 2, showing the low profile valve in the
closed position.
[0041] FIG. 4 is a longitudinal cross-sectional view of an
alternative embodiment, showing the low profile valve in the closed
position.
[0042] FIG. 5 is a longitudinal cross-sectional view of the
embodiment of FIG. 4, showing the low profile valve in the open
position.
[0043] FIG. 6 is a longitudinal cross-sectional view of an
alternative embodiment of the low profile valve, depicting the
valve in the open position
[0044] FIG. 7 is a longitudinal cross-sectional view of the
embodiment of FIG. 6, depicting the valve in the closed
position.
[0045] FIG. 8 is a perspective view of an inflation adaptor used to
manipulate the low profile valve of the present invention.
[0046] FIG. 9A is a perspective view of the interior of the
inflation adaptor of FIG. 8.
[0047] FIG. 9B is a perspective view of a catheter with a sealing
member and alignment indicia being positioned in the inflation
adaptor of FIG. 9A.
[0048] FIG. 10 is an end view of an alternative embodiment of the
inflation adaptor.
[0049] FIG. 11 is a cross-sectional view of the inflation adaptor
of FIG. 10 along lines 10-10.
[0050] FIGS. 12 and 13 are exploded views of alternative
embodiments of the low profile valve of the present invention.
[0051] FIG. 14 is an alternative embodiment of the valve of the
present invention featuring a built in spring bias.
[0052] FIGS. 15A and 15B are longitudinal cross-sectional views of
the catheter proximal end of FIG. 14, showing the valve in the
closed and open position, respectively.
[0053] FIG. 16 is a perspective view of an alternative embodiment
of an inflation adaptor used to manipulate the low profile valve of
the present invention.
[0054] FIG. 17 is a perspective view of the interior of the
inflation adaptor of FIG. 16.
[0055] FIGS. 18A and 18B are top views of the inflation adaptor of
FIGS. 16 and 17, illustrating the latch locking mechanism.
[0056] FIGS. 19A-19C are schematic cross-sectional views of the
adaptor of FIG. 16, which illustrate the cam locking door mechanism
which provides mechanical advantage to the adaptor locking
latch.
[0057] FIGS. 20A-C are close-up views of an embodiment of the
adaptor having a sliding top panel biased by a spring
mechanism.
[0058] FIGS. 21 and 22 are cross-sectional views of a proximal
section of a catheter having an alternative embodiment of the valve
of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0059] Referring to FIG. 1, there is depicted a catheter 10
incorporating the low profile valve of the present invention.
Although illustrated in the context of a simple occlusion balloon
catheter, having a single inflation lumen and a single inflatable
balloon, it is to be understood that the low profile valve of the
present invention can be readily adapted to a wide variety of
balloon catheters, including those having additional
functionalities, structures, or intended uses. For example, the low
profile valve could be easily adapted to catheters having
expandable members other than occlusion balloons, such as
therapeutic dilatation balloons. Furthermore, the low profile valve
of the present invention may also be incorporated into catheters
having two or more lumens. The manner of adapting the low profile
valve of the present invention to catheters having these various
functionalities, structures, or intended uses will become readily
apparent to those of skill in the art in view of the description
which follows.
[0060] Catheter 10 generally comprises an elongate flexible tubular
body 18 extending between a proximal control end 12 and a distal
functional end 14. Tubular body 18 has a central lumen 40 which
extends between ends 12 and 14. Lumen 40 has an opening 23 at
proximal end 12, and is sealed fluid tight at distal end 14. The
length of tubular body 18 may be varied considerably depending upon
the desired application. For example, where catheter 10 is to be
used as a guidewire for other catheters in a conventional
percutaneous transluminal coronary angioplasty procedure involving
femoral artery access, lengths of tubular body 18 in the range of
from about 120 to about 300 centimeters are preferred, with a
length of about 180 centimeters often being used. Alternately, for
a different treatment procedure, not requiring as long a length of
tubular body 18, shorter lengths of tubular body 18 may be
provided.
[0061] Typically, tubular body 18 will have a generally circular
cross-sectional configuration with an outer diameter within the
range of from about 0.010 inches to 0.044 inches. Optimally, in
most applications where catheter 10 is to be used as a guidewire
for other catheters, the outer diameter of tubular body 18 ranges
from 0.010 inches to 0.038 inches, and preferably is 0.020 inches
in diameter or smaller, more preferably 0.014 inches in outer
diameter or smaller. The diameter of lumen 40 will be dictated, in
part, by the outside diameter of tubular body 18. For example,
where tubular body 18 has an outer diameter of 0.014 inches,
central lumen 40 may have an inner diameter of from about 0.008
inches to about 0.010 inches. The diameter of lumen 40 should be
large enough to incorporate the low profile valve described below,
and large enough to permit sufficient fluid passage for balloon
inflation.
[0062] Noncircular cross-sectional configurations of lumen 40 can
also be adapted for use with the low profile valve of the present
invention. For example, triangular rectangular, oval, and other
noncircular cross-sectional configurations are also easily
incorporated for use with present invention, as will be appreciated
by those of skill in the art. The manner of adapting the valve of
the present invention will become readily apparent in view of the
description which follows.
[0063] In the preferred embodiment, the tubular body 18 functions
as a guidewire, and thus, tubular body 18 must have sufficient
structural integrity, or "pushability," to permit catheter 10 to be
advanced through vasculature to distal arterial locations without
buckling or undesirable bending of tubular body 18. It is also
desirable for tubular body 18 to have the ability to transmit
torque, such as in those embodiments where it may be desirable to
rotate tubular body 18 after insertion into a patient. A variety of
biocompatible materials, known by those of skill in the art to
possess these properties and to be suitable for catheter
manufacture, may be used to fashion tubular body 18. For example,
tubular body 18 may be made of stainless steel, or may be made of
polymeric materials such as nylon, polyamide, polyimide,
polyethylenes, or combinations thereof. In one preferred
embodiment, the desired properties of structural integrity and
torque transmission are achieved by forming tubular body 18 out of
an alloy of titanium and nickel, commonly referred to as nitinol.
In a more preferred embodiment, the nitinol alloy used to form
tubular body 18 is comprised of about 50.8% nickel and the balance
titanium, which is sold under the trade name TINEL (TM) by Memry
Corp. It has been found that a catheter tubular body having this
composition of nickel and titanium exhibits great flexibility and
improved kink resistance in comparison to other materials. One
preferred embodiment of tubular body 18 is disclosed in our
copending application entitled HOLLOW MEDICAL WIRES AND METHODS OF
CONSTRUCTING SAME, application Ser. No. 08/812,876, filed on Mar.
6, 1997, now U.S. Pat. No. 6,068,623, the entirety of which is
incorporated herein by reference.
[0064] The distal end 14 of catheter 10 is provided with an
atraumatic distal tip 16, and an inflatable balloon 20, as
illustrated in FIG. 1. Inflatable balloon 20 may be made from any
of a variety of materials known by those of skill in the art to be
suitable for balloon manufacture. For example, inflatable balloon
20 may be formed of materials having a compliant expansion profile,
such as polyethylene or latex. In one preferred embodiment, where
inflatable balloon 20 is to be used as an occlusion balloon, it is
preferably formed of a block copolymer of
styrene-ethylene-butylene-styrene (SEBS), sold under the trade name
C-FLEX (TM). One preferred embodiment of a C-FLEX occlusion balloon
is disclosed in our copending application entitled PRE-STRETCHED
CATHETER BALLOON, application Ser. No. 08/812,140, filed on Mar. 6,
1997, now U.S. Pat. No. 5,868,705, the entirety of which is
incorporated herein by reference. Alternately, in those embodiments
where inflatable balloon 20 is to serve as a dilatation balloon, it
may be formed of materials having a noncompliant expansion profile,
such as polyethylene terephthalate. Inflatable balloon 20 may be
attached to tubular body 18 in any manner known to those of skill
in the art, such as heat bonding or through use of adhesives.
[0065] As shown in FIG. 1, catheter 10 is provided with a
side-access inflation port or opening 22 formed in tubular body 18
at a point several centimeters distal from opening 23. Inflation
port 22 is in fluid communication with central lumen 40 extending
through tubular body 18. A fill hole (not shown) is formed in
tubular body 18 within the region enclosed by inflatable balloon
20, such that fluid passing through inflation port 22 and into
lumen 40 may inflate balloon 20. Conversely, an inflated balloon 20
can be deflated by withdrawal of fluid from balloon 20, through
lumen 40, and out of side-access inflation port 22.
[0066] The low profile valve of the present invention may be used
with catheters such as that described above, all well as with
different catheters having different structures. In one preferred
embodiment, the low profile valve comprises a sealing member which
is movably positioned within the inner lumen of a catheter. The
catheter has an inflation port, which, in some embodiments, is also
an opening to the inner lumen at the proximal end of the catheter.
An inflatable balloon is positioned on the distal end of the
catheter, which is in fluid communication with the lumen and
inflation port. The sealing member is inserted through the proximal
opening into the lumen, with a portion of the sealing member
extending outwardly from the proximal end of the catheter. The
portion of the sealing member inserted into the lumen has a sealer
portion which forms a fluid tight seal with the inner lumen to
prevent fluid from passing past the sealer portion.
[0067] By application of a pushing or pulling force on the
extending sealing member portion, the sealing member may be
partially advanced within or withdrawn from the lumen, thereby
moving the sealer portion within the lumen. In this manner, the
sealer portion may be positioned within the lumen either proximally
or distally of the inflation port. When the sealer portion is
positioned proximally of the port, the valve is in the "open"
position. When the valve is open, an unrestricted fluid pathway is
established between the inflation port and the balloon, such that
an external pressurized fluid source may be connected to the
inflation port to inflate the balloon, or if the balloon is already
inflated, the balloon may be deflated by application of a vacuum to
the inflation port to withdraw fluid from the balloon. When the
sealer portion is positioned distally of the inflation port, the
valve is in the closed position, as the fluid tight seal between
the lumen and the sealer portion prevents fluid from passing either
to or from the balloon through the inflation port. Furthermore,
when the valve is closed after balloon inflation, the fluid tight
seal created by the sealer portion maintains the balloon in the
inflated state in the absence of an external fluid source, by
preventing the pressurized fluid within the balloon from
escaping.
[0068] Referring to FIGS. 2, 3A and 3B, there is depicted one
embodiment of the low profile valve of the present invention, as
used with the catheter of FIG. 1. Catheter 10, as described above,
has a side-access inflation port 22 which is in fluid communication
with central lumen 40, and through which fluid may be introduced to
inflate balloon 20. Central lumen 40 has an opening 23 at proximal
end 12. A sealing member 30 is inserted into lumen 40 through
opening 23. Sealing member 30 may be partially advanced within or
withdrawn from lumen 40 by the application of a longitudinal force
on sealing member 30 directed toward or away from proximal end 12,
respectively.
[0069] Sealing member 30 comprises a main shaft 33, a tapering
region 31, and a wire 32. Sealing member 30 may be formed as solid
piece out of suitable metals, such as stainless steel, nitinol and
the like. For example, sealing member 30 may be formed as a solid
cylindrical piece, and then be coined down at points along its
length to form tapering region 31 and wire 32. Alternately, one or
more of the main shaft 33, tapering region 31, or wire 32 may be
formed separately, and then attached to the other piece(s) by
conventional means, such as soldering, to form sealing member 30.
Polymeric materials, such as DELRON (TM), nylon, and the like, may
also be used to form sealing member 30, either as a solid piece, or
as separate pieces which are later joined to form the sealing
member.
[0070] Although not required, in one preferred embodiment, main
shaft 33 has an outer diameter no larger than the outer diameter of
the catheter tubular body 18. Thus, if the outer diameter of
tubular body 18 is 0.014 inches, the diameter of main shaft 33, and
thus the largest diameter of sealing member 30, is no larger than
0.014 inches. Furthermore, it is also preferred that main shaft 33
extend proximally from opening 23 by a distance of at least several
centimeters to facilitate the application of longitudinal forces on
main shaft 33 to manipulate the position of wire 32 in lumen 40.
Moreover, after catheter 10 has been fully inserted into a patient,
an extending main shaft 33 advantageously functions much like a
conventional guidewire extension, providing a starting point for
the clinician to insert other catheters over main shaft 33 and
catheter 10.
[0071] The combined length of catheter 10 and extending main shaft
33 may be varied considerably at the point of manufacture, and may
be adapted to the requirements of the other catheters which are to
be used with catheter 10 and main shaft 33. For example, where
catheter 10 is to be used as a guidewire for other catheters in an
"over-the-wire" embodiment, it is preferred that the total length
of catheter 10 with extending main shaft 33 be about 300
centimeters. Alternately, when catheter 10 is to be used as a
guidewire for other catheters in a single operator embodiment, or
"RAPID-EXCHANGE" embodiment, it is preferred that the total length
of catheter 10 with extending main shaft 33 be about 180
centimeters. As can be readily appreciated, the individual lengths
of catheter 10 and extending main shaft 33 can be varied
considerably and yet still achieve the overall desired combined
length. For example, a catheter 10 having a length of 180
centimeters can be provided with an extending main shaft 33 having
a length of 120 centimeters, to achieve the 300 centimeter total
desired length for over-the-wire embodiments.
[0072] In another embodiment, where it is undesirable to have a
long main shaft extending proximally from catheter 10, a main shaft
extending proximally only several centimeters may be provided. The
shorter main shaft may be provided with an attachment (not shown),
which is adapted to releasably secure longer extensions to the main
shaft, such that it can also be used to facilitate the use of
catheter 10 as a guidewire for other catheters.
[0073] It is preferred that main shaft 33 have a larger diameter
than the other portions of sealing member 30, to make it easier to
apply moving forces to sealing member 30. Thus, a tapering region
31 may be disposed between main shaft 33 and wire 32, to transition
the outer diameter of sealing member 30 from the larger diameter of
main shaft 33 to the smaller diameter of wire 32. For the
embodiment illustrated in FIGS. 1-3, it is wire 32 which is
slidably inserted through opening 23 and into lumen 40.
Accordingly, the outer diameter of wire 32 must be less than the
inner diameter of lumen 40, so that wire 32 may be slidably
accommodated therein. Moreover, in those embodiments where the end
of wire 32 extends distally past inflation port 22 when the valve
is in the open position, the gap between the outer diameter of wire
32 and the inner diameter of lumen 40 must be sufficiently large so
as not to significantly restrict the flow of fluid passing through
lumen 40 to or from inflation port 22. Optimally, to facilitate the
sliding of wire 32 within lumen 40 and to permit inflation fluid
flow, wire 32 is from about 0.001 inches to about 0.004 inches
smaller in outer diameter than the inner diameter of lumen 40.
[0074] In a preferred embodiment, wire 32 and catheter 10 are
provided with positive stops to prevent the withdrawal of wire 32
from the proximal end of catheter 10. For the embodiment depicted
in FIGS. 3A and 3B, this consists of a pair of cooperating annular
rings mounted on wire 32 and lumen 40, respectively. A first
annular ring 34 is coaxially and fixedly mounted on wire 32 at a
point on wire 32 contained within lumen 40. A second corresponding
fixed annular ring 35 projects inwardly from the interior surface
of lumen 40 near proximal end 12. The inner diameter of the opening
of annular lumen ring 35 is slightly larger than the outer diameter
of wire 32, so as not to restrict the movement of wire 32 within
lumen 40. However, the outer diameter of annular wire ring 34 is
greater than the inner diameter of the opening of ring 35, such
that rings 34 and 35 cooperate to prevent wire 32 from being
withdrawn from the proximal end of catheter 10.
[0075] Rings 34 and 35 may be formed of any material which may be
attached to wire 32 and lumen 40, respectively, and which possesses
sufficient structural rigidity to act as a stop. Examples of
suitable materials are metals and various hard polymers, such as
stainless steel and TEFLON (TM). In one preferred embodiment, where
wire 32 and tubular body 18 are both formed of nitinol, rings 34
and 35 are also formed of nitinol and are soldered to wire 32 and
the inner surface of lumen 40, respectively.
[0076] As will be appreciated by those of skill in the art,
cooperating stopping structures other than those described herein
may also be used to prevent full withdrawal of wire 32 from
catheter 10. For example, annular ring 34 may be replaced by one or
more protrusions extending radially outwardly from wire 32, which
are also adapted to cooperate with ring 35 to prevent withdrawal of
wire 32. Alternately, annular ring 35 might be replaced by crimping
tubular body 18 slightly to restrict movement of ring 34 to points
proximal of the crimp.
[0077] A lumen sealer portion 36 is coaxially and fixedly mounted
on wire 32. Sealer portion 36 is positioned on wire 32 at a point
distal to ring 34, such that by partial withdrawal of wire 32 from
catheter 10, as depicted in FIG. 3A, sealer portion 36 is capable
of being positioned within lumen 40 at a point proximal to
inflation port 22. Sealer portion 36 is also located on wire 32 at
a point such that when wire 32 is filly inserted into lumen 40, as
depicted in FIG. 3B, sealer portion 36 either filly covers
inflation port 22, or is located within lumen 40 at a point distal
to inflation port 22. The leading edge 36a and trailing edge 36b of
sealer portion 36 are preferably tapered, so that the edges of
sealer portion 36 do not catch upon inflation port 22 when sealer
portion 36 passes by port 22.
[0078] It is preferred that sealer portion 36 form a fluid tight
seal with the outer diameter of wire 32 and the inner diameter of
lumen 40, such that fluid in lumen 40 is prevented from flowing
past sealer portion 36. In the embodiment illustrated in FIGS. 3A
and 3B, this is achieved by providing wire 32 with a sealer portion
36 that firmly contacts the entire inner circumference of a section
of lumen 40 along a substantial portion of the length of sealer
portion 36. The fit between the outer surface of sealer portion 36
and the inner surface of lumen 40 is tight, such that a fluid tight
seal is created which prevents fluid from passing past sealer
portion 36. However, sealer portion 36 must be capable of being
moved within lumen 40 upon movement of main shaft 33, tapering
region 31, and wire 32. Thus, the fit between sealer portion 36 and
lumen 40 must not be so tight as to prevent movement of sealer
portion 36 in lumen 40 upon application of sufficient longitudinal
force on main shaft 33. Moreover, the fluid tight seal created by
the fit between lumen 40 and sealer portion 36 must be maintained
as sealer portion 36 is moved back and forth within lumen 40.
[0079] Sealer portion 36 must also be capable of maintaining a seal
at fluid pressures conventionally used to inflate catheter
balloons, and should be capable of maintaining a seal at pressures
which exceed conventional inflation pressures. Preferably, sealer
portion 36 is capable of maintaining a seal at pressures up to
about 10 atmospheres, more preferably pressures up to about 30
atmospheres, and most preferably at pressures up to about 60
atmospheres. Sealer portion 36 is also preferably capable of
undergoing multiple valve-opening and valve-closing cycles without
losing the structural integrity required to form seals capable of
withstanding pressures of from about 10 atmospheres to about 60
atmospheres. Optimally, sealer portion 36 is capable of undergoing
at least 10, and preferably at least 20, valve-opening and closing
events and still be capable of maintaining a fluid tight seal at a
pressure of 10 atmospheres.
[0080] In one embodiment, the desired properties of sealer portion
36 are attained by forming sealer portion 36 out of an extruded
polymeric tubing. PEBAX (TM) tubing having an inner diameter of
0.008 inches and an outer diameter of 0.017 inches, and a hardness
of 40 durometers, is first necked by heating the extruded tubing to
a temperature of between 210 and 250 degrees Fahrenheit. Tube
pieces of about 0.5 mm in length are then cut from the larger
tubing. The cut PEBAX (TM) tubes are then placed on a nitinol wire
having an outer diameter of about 0.006 inches, and are heated and
shaped to recover a tube that has an outer diameter of between
0.010-0.011 inches. The adhesive LOCTITE 4014 (TM) may then be used
to bond the heat-shaped PEBAX (TM) tubing to the nitinol wire. When
the adhesive dries, the leading and trailing edges of the bound
PEBAX (TM) seal may be trimmed, leaving an annular lumen contact
length of about 0.010 inches (0.25 mm). The wire bearing the PEBAX
(TM) sealer portion may then be inserted into the opening of a
nitinol catheter having a lumen with an inner diameter of about
0.0096 inches. Sealer portions of this type have been observed to
hold pressures of up to 30 atmospheres, and are capable of
undergoing multiple valve-opening and closing events without
significantly diminishing the seal strength.
[0081] As will be appreciated by those of skill in the art,
different forms of PEBAX (TM) starting materials may be used to
form sealer portion 36. For example, in another preferred
embodiment, similar steps were used with a PEBAX (TM) tube having
similar dimensions but a hardness of 70 durometers, to create a
sealer portion.
[0082] It is contemplated by the present inventors that methods and
materials other than those described above may be used to make a
lumen sealer portion having the desired properties. For example,
materials other than PEBAX (TM), silicone, latex rubber, C-FLEX
(TM), NUSIL (TM) and gels, which are known to possess adequate
surface properties to function as a sealer portion, and also be
lubricous enough to be moved within lumen 40, may also be used to
form sealer portion 36. In addition, sealer portion 36 may be
attached to wire 32 by alternate means, such as by integrally
molding sealer portion 36 to wire 32, dip forming sealer portion 36
to wire 32, as well as other means of attaching a polymeric
material to a wire known to those of skill in the art.
[0083] Other embodiments of sealer portion may not create a
completely fluid tight seal between the sealer portion and the
inner lumen at balloon inflation pressures. In these embodiments,
however, the sealer portion creates a seal which prevents
substantially all inflation fluid flow past the sealer portion,
such that the inflatable occlusive device is maintained in an
almost fully expanded state for extended periods of at least one
minute, preferably 2 or more minutes, more preferably at least 10
minutes, and optimally at least 20 minutes or longer, and still be
capable of providing clinically effective occlusion of any emboli
particles in the blood vessel during this time period.
[0084] In a preferred embodiment, there is provided movement-force
increasing structure, to increase the force required to move sealer
portion 36 from the valve-closed to the valve-open position.
Structure of this type advantageously minimizes the risk of an
accidental opening of the valve, and subsequent balloon deflation,
during a medical procedure. In the embodiment illustrated in FIGS.
3A and 3B, this is achieved by providing a biasing spring 37, which
surrounds wire 32 between stops 34 and 35. Spring 37 exerts a force
on stop 34, pushing it, and thus wire 32 and sealer portion 36, in
the distal direction, so that sealer portion 36 forms a fluid tight
seal by either covering port 22 or by being positioned within the
lumen at a point distal to port 22. Consequently, in the absence of
a competing force, spring 37 maintains sealer portion 36 in the
valve-closed position. Sealer portion 36 may be moved proximally to
the valve-open position by application of a longitudinal force on
main shaft 33 directed proximally from end 12 of sufficient
magnitude to overcome the force of spring 37. Optimally, spring 37
is selected so that the force that must be applied to main shaft 33
to overcome the force of spring 37 is from about 0.3 to about 1.0
pound-foot. In alternative embodiments, the movement force
increasing structure may comprise waves introduced into the wire
just proximal of the sealer portion, as described below, which also
may require 0.3 to 1.0 pound-foot of force to overcome.
[0085] Referring to FIGS. 4 and 5, there is illustrated in
alternative embodiment of the valve of the present invention. The
alternative embodiment comprises a catheter 110 which may have
features which are substantially identical, in materials,
structure, and function, as the catheter described in connection
with FIGS. 1-3. Catheter 110 has a proximal end 112, and a distal
end (not shown) to which is mounted an expandable member, such as
an inflatable balloon. A central lumen 140 extends within tubular
body 118 between the proximal and distal ends. An opening 123 to
lumen 140 is present at the proximal end 112 of catheter 110.
[0086] A sealing member 130 is inserted into lumen 140 through
opening 123, as described previously. Sealing member 130 comprises
a sealer portion 136, a wire 132, annular rings 134 and 135, and
support member 150. Sealing member 130 may be formed out of
materials and by methods as described previously.
[0087] As illustrated in FIGS. 4 and 5, the outer diameter of wire
132 is less than the inner diameter of lumen 140, such that sealing
member 130 is sidably insertable into lumen 140. Furthermore, a
lumen sealer portion 136 is coaxially and fixedly mounted to wire
132 near the distal end of wire 132. Sealer portion 136 forms a
fluid tight seal with the outer diameter of wire 132 and the inner
diameter of lumen 140, such that fluid introduced into lumen 140
through opening 122 is prevented from flowing past sealer portion
136 at normal balloon inflation pressures of 1 to 3 atmospheres for
occlusive devices, and as much at 10 atmospheres or more for other
types of balloons. Sealer portion 136 may be provided with leading
edge 136a and trailing edge 136b, both tapered, to facilitate
movement of sealing portion 136 proximally and distally of
inflation port 122. Sealer portion 136 forms a fluid tight seal by
firming contacting the entire inner circumference of a section of
lumen 140 along a substantial portion of the length of sealer
portion 136. As described previously, sealer portion 136 prevents
substantially all fluid flow past the seal created by sealer
portion 136, and the movement of sealer portion 136 proximally and
distally of port 122 may be used to effect the valve-open and
valve-closed positions.
[0088] Cooperating positive stops, consisting of hollow cylinders
134 and 135 are provided to prevent withdrawal of sealing member
130 from lumen 140. Hollow cylinder 135 is attached to the inner
surface of lumen 140 by adhesives, soldering, crimping, or by other
means known to those of skill in the art, such that the proximal
portion of hollow cylinder 135 extends within lumen 140, and is
secured therein, and the distal portion of cylinder 135 extends
from proximal end 112. Cylinder 135 has a lumen (not shown)
extending therethrough. The diameter of the cylinder lumen is
larger than the outer diameter of wire 132, so that movement of
wire 132 is not restricted. A second hollow cylinder 134,
preferably of shorter length, is placed over wire 132 and is
fixedly mounted to wire 132, by soldering, or other means, at a
point distal to cylinder 135. The outer diameter of cylinder 134 is
less than the inner diameter of lumen 140, so as not to restrict
the movement of wire 132 within lumen 140. However, the outer
diameter of cylinder 134 is greater than the inner lumen diameter
of cylinder 135, so that cylinders 134 and 135 act as cooperating
stops, to prevent wire 132 from being withdrawn from lumen 140.
Cylinders 134 and 135 may be formed of any material which may be
attached to wire 132 and lumen 140, respectively, and which
possesses sufficient structural rigidity to act as a stop. Examples
of suitable materials are metals and various hard polymers, such as
stainless steel, TEFLON (TM), and the like. In one preferred
embodiment, where wire 132 and tubular body 118 are both formed of
nitinol, cylinders 134 and 135 are also formed of nitinol, and are
soldered to wire 132 and the inner surface of lumen 140,
respectively.
[0089] The distal portion of cylinder 135 extending from proximal
end 112 is inserted into support member 150. Support member 150
comprises a tubular body 158 having an outer diameter and inner
lumen diameter which are approximately the same as tubular body
118. Consequently, because the outer diameter of cylinder 135 is
less than the inner lumen diameter of support member 150, the
extending portion of cylinder 135 is slidably disposed within the
support member 150 inner lumen.
[0090] Wire 132 extends proximally from cylinder 135 within support
member 150, as shown in FIGS. 4 and 5. A segment of wire 132 within
support member 150 is secured to support member 150 at point 152.
Wire 132 may be secured to support member 150 by any means known to
those of skill in the art, including use of adhesives, crimping,
soldering or welding. Because wire 132 is secured to support member
150, the application of longitudinal forces on support member 150
results in movement of sealing member 130 within lumen 140, to open
or close the valve of the present invention, as described above
with respect to FIGS. 1-3. Advantageously, use of support member
150 protects wire 132 from undesirable kinking or bending when
sealing member 130 is moved.
[0091] As illustrated in FIGS. 4 and 5, sealing member 130 has
movement-force increasing structure which increases the force
required to move sealing member 130 within lumen 140. The
movement-force increasing structure consists of waves 138 formed in
wire 132 just proximal to sealer portion 136. Waves 138 contact the
inner surface of lumen 140, thereby increasing the frictional
forces which must be overcome to move wire 132 within lumen 140. In
one preferred embodiment, where wire 132 is made of nitinol and has
an outer diameter of 0.006 inches, and is inserted into a nitinol
catheter which has an inner lumen 140 with the diameter of about
0.010 inches, waves are forned on wire 132 for one and one-half
cycles with an amplitude of about 0.016 inches to increase the
valve- opening movement force.
[0092] Referring to FIGS. 6 and 7, there is illustrated another
embodiment of the present invention. Referring to FIG. 6, there is
provided a catheter 400 having a tubular body 418 and inflatable
balloon (not shown) as described above. Catheter 400 may be formed
of materials and methods as described above, and may have
structural aspects identical to those described previously, except
where otherwise noted. In particular, as shown in FIGS. 6 and 7,
catheter 400 is not provided with a side-access port on the
catheter tubular body, nor is there provided cooperating positive
stops on the wire and lumen. Instead, the sealer portion may be
fully withdrawn from the lumen. Once the sealer portion is removed,
the proximal opening serves as an access port for attached devices
to inflate or deflate the balloon. The sealer portion can be
inserted through the proximal opening into the lumen after balloon
inflation to maintain the balloon in the inflated state.
[0093] Catheter 400 has a proximal end 412, and a distal end (not
shown) to which is mounted an inflatable balloon. A central lumen
440 extends within tubular body 418 between the proximal and distal
ends. An opening 423 to lumen 440 is present at the proximal end
412 of catheter 400.
[0094] A sealing member 430 is inserted into lumen 440 through
opening 423. Sealing member 430 has a main shaft 433, a tapering
region 431, and a wire 432. Sealing member 430 may be formed of
materials and by methods as described previously. As illustrated in
FIGS. 6 and 7, the outer diameter of main shaft 433 is less than
the inner diameter of lumen 440, such that main shaft 433 is
slidably insertable into lumen 440. In addition, the outer
diameters of tapering region 431 and wire 432 are also smaller than
main shaft 433, and thus lumen 440, such that tapering region 431
and wire 432 are also slidably insertable in lumen 440. A portion
of main shaft 433 preferably extends proximally from end 412, to
facilitate application of moving forces upon sealing member 430 to
move wire 432 within lumen 440, as described previously.
[0095] As illustrated in FIGS. 6 and 7, sealing member 430 has
movement-force increasing structure which increases the force
required to move sealing member 430 within lumen 440. The
movement-force increasing structure consists of waves 438a and 438b
formed in wire 432 near its distal end. Waves 438a and 438b contact
the inner surface of lumen 440, thereby increasing the frictional
force which must be overcome to move wire 432 within lumen 440. In
one preferred embodirnent, where wire 432 is made of nitinol and
has an outer diameter of 0.006 inches, and is inserted into a
nitinol catheter which has an inner lumen 440 with a diameter of
about 0.010 inches, waves are formed on wire 432 for 11/2 cycles
with an amplitude of about 0.016 inches to increase the
valve-opening movement force.
[0096] A lumen sealer portion 436 is coaxially and fixedly mounted
on wire 432. Sealer portion 436 forms a fluid tight seal with the
outer diameter of wire 432 and the inner diameter of lumen 440,
such that fluid introduced into lumen 440 through opening 423 is
prevented from flowing past sealer portion 436 when sealer portion
436 is inserted into lumen 440. Sealer portion 436 forms the fluid
tight seal by firmly contacting the entire inner circumference of a
section of lumen 440 along a substantial portion of the length of
sealer portion 436, and may be formed of materials and by methods
as previously described.
[0097] In some removable sealing member embodiments, the sealing
member is not provided with a separate sealing portion, as
described above. In these embodiments, the sealing member itself
functions as a sealing portion which is inserted into the proximal
opening to restrict fluid flow, and which may be partially or
wholly removed to provide for a fluid pathway between the proximal
opening and an expandable member on the distal end of the catheter.
Preferably, the sealing members of these embodiments comprise a
tapering rod, which at its distal end, has an outer diameter
smaller than the inner lumen diameter of the catheter in which it
is inserted as a plug, such that the distal end of the rod may be
easily inserted into the catheter lumen through the proximal
opening. The tapering rod increases in outside diameter at points
proximal to the distal end. Consequently, one or more points of the
rod have an outside diameter greater than the inner lumen diameter
of the catheter in which it is inserted as a plug, such that by
forcing the rod into proximal opening, the larger outer diameter of
the rod forms a relatively fluid tight seal with the catheter lumen
at the proximal opening of the catheter. An O-ring, or other
polymeric structure, may be mounted in the inner lumen of the
catheter at or near the proximal opening, to cooperate with the
tapering rod in the creation of the seal. Thus, in this embodiment,
the point where the seal is created does not move with respect to
the catheter, but is instead stationary at or near the proximal
opening of the catheter.
[0098] Referring to FIG. 12, there is depicted an alternative
embodiment of the valve the present invention. The alternative
embodiment is provided to a catheter 500, formed of a tubular body
518 and having a proximal end 512. Catheter 500 has an opening 523
at is proximal end, and a lumen 540 extending the length of the
tubular body. Lumen 540 is in fluid communication with an
expandable member (not shown) mounted on the distal end of tubular
body 518. A side-access port 522 is provided in tubular body 518 at
a point distal to proximal end 512. Catheter 500 may have aspects
identical, both in structure, dimensions, materials, and
construction, to catheters described previously.
[0099] A sealing member 550 is positioned within lumen 540 near
proximal opening 523 and side-access port 522. Sealing member 550
is formed from a short tubular body 568, having a lumen 590, which
is sealed at end 562, but open at the other end. Sealing member 550
has an outer diameter slightly larger that the inner diameter of
lumen 540, but smaller than the outer diameter of tubular body 518,
such that sealing member 550 may be tightly fit within lumen 540
through opening 523, to form a fluid tight seal over catheter
proximal opening 523. Cooperating stopping structures (not shown)
may be provided to sealing member 550 and catheter 500 to prevent
removal of sealing member 550 from lumen 540 at elevated pressures.
Sealing member 550 may be formed out of the same materials as
tubular body 518.
[0100] Tubular body 568 is provided with an opening 572 extending
therethrough. Opening 572 is positioned on tubular body 568 such
that opening 572 is capable of aligning with side-access port 522
when sealing member 550 is rotated within lumen 540, or is moved
proximally or distally within lumen 540. A rotation element 595,
such as a perpendicular attachment, may be provided facilitate
rotation of sealing member 550 within lumen 540. Other rotation
elements, such as notches or grooves, may be used in place of the
perpendicular attachment, as will be appreciated by those of skill
in the art.
[0101] Sealing member 550 functions as a valve within catheter 500,
controlling fluid flow through side-access port 522. When sealing
member 550 is rotated so that port 522 and opening 572 are aligned,
fluid may flow through port 522 through lumen 540 to inflate the
occlusive device. Upon the desired inflation, sealing member 550
may be rotated, as for example by ninety degrees, or moved
proximally or distally within lumen 540, such that opening 572 is
no longer aligned with port 522, and tubular body 568 blocks fluid
flow through port 522.
[0102] Shown in FIG. 13, is an alternative embodiment of the
rotatable sealing member. Numerals corresponding to those of the
embodiment of FIG. 12 have been used to illustrate the similar
structural aspects between the two embodiments. Sealing member 600
is identical in construction to the sealing member of FIG. 12,
except that sealing member 650 is somewhat larger, and is adapted
to be slipped over tubular body 618. The respective diameters of
tubular body 618 and sealing member lumen 690 are such that a fluid
tight seal is created over lumen 623. Side-access inflation port
622 may be aligned with opening 672, as above, by rotation or
longitudinal movement, to provide fluid access to lumen 640 through
port 622.
[0103] In certain embodiments, it may be desirable for sealing
members 550 and 650 to have a longer length, such that they may
function as an extension for other catheters to be inserted over
catheters 500 and 600. In these embodiments, sealing members 550
and 650 may be formed with longer tubular bodies, or be provided
with attachments so that extension members may be releasably
secured thereto.
[0104] Referring to FIGS. 14, 15A and 15B, there is illustrated an
alternative embodiment of the present invention featuring a
self-closing valve. The alternative embodiment comprises a catheter
700 having an elongate flexible tubular body 718 extending between
a proximal control end 712 and a distal functional end (not shown),
and having a balloon (not shown) as described previously. Tubular
body 718 has central lumen 740 which extends between the proximal
and distal ends. Lumen 740 has an opening 723 at proximal end 712,
and is sealed fluid tight at the distal end. A side access
inflation port 722 is formed in tubular body 718 at a point distal
of opening 723. Inflation port 722 and lumen 740 are in fluid
communication with the distal inflatable balloon, as described
previously.
[0105] A wire 732 is inserted into opening 723, and is slidably
disposed within lumen 740. Accordingly, the outer diameter of the
wire 732 must be less than the inner diameter of lumen 740, so that
wire 732 may be slidably accommodated therein. A sealer portion 736
is coaxially mounted on wire 732. Sealer portion 736 is of similar
type and construction to the sealer portion described in connection
with FIGS. 1-3. Sealer portion 736 is positioned on wire 732 at a
point distal to inflation port 722, and forms fluid-tight seal with
the outer diameter of wire 732 and the inner diameter of lumen 740,
such that fluid introduced into lumen 740 is prevented from flowing
past sealer portion 736. Consequently, because sealer portion 736
is positioned with lumen 740 distal to inflation port 722, sealer
portion 736 is in the valve-closed position.
[0106] In the embodiment depicted in FIGS. 14-15B, tubular body 718
is formed from a material having a certain degree of elasticity,
such that if the proximal end 712 of tubular body 718 is secured to
wire 732 at point 750, and a longitudinal force is applied to
tubular body 718 in a direction distal to end 712, the elasticity
of tubular body 718 results in the shifting of inflation port 722
in the distal direction. Moreover, slits 711 may be formed in
tubular body 718 near proximal end 712 to enhance the elastic
response of tubular body 718, thereby increasing the distal
translocation of inflation port 722 upon application of an axial
force to tubular body 718. Wire 732 may be secured to tubular body
718 by any means known to those of skill in the art, such as
adhesives, welding, soldering, or crimping.
[0107] In a preferred embodiment, tubular body 718 is made out of
nitinol, and has at least 8% elasticity when longitudinal slits 711
are introduced at the proximal end. As can be observed in FIG. 15A,
in the absence of any longitudinal force applied to tubular body
718, sealer portion 736 is positioned within lumen 740 at a point
distal to inflation port 722, such that fluid may not pass through
port 722 to inflate or deflate the balloon. However, if a
longitudinal force is applied to tubular body 718 in the distal
direction, and the proximal end of tubular body 718 and wire 732
are held in position, tubular body will stretch, as shown in FIG.
15B, and inflation port 722 will be translocated in the distal
direction so that sealer portion 736 will be located within the
lumen proximally of port 722. This will establish an unrestricted
fluid pathway between inflation port 722 and the distal balloon, so
that the balloon may be either inflated or deflated by passage of
fluid through port 722. Upon removal of the longitudinal force, the
elastic response of tubular body 718 will result in proximal
translocation of inflation port 722, and sealer portion 736 will
once again be in the valve-closed position.
[0108] Referring to FIGS. 8 and 9A, there is illustrated an
inflation adaptor 200 which may be used to inflate and to open and
close the low profile valve depicted in FIGS. 1-5. Inflation
adaptor 200 comprises a housing having a first half 202 and a
second half 204, which are preferably formed of metal, medical
grade polycarbonate, or the like. Halves 202 and 204 are attached
to one another by a pair of hinges 205 positioned on one of the
lateral edges of each half, such that halves 202 and 204 may be
separated or joined in a clam shell manner as depicted in FIGS. 8
and 9. A locking clip 230 secures half 202 to half 204 while
inflation adaptor 200 is in use. Locking clip 230 may be provided
with an angled leading edge 235 to facilitate closing of clip 230
to secure halves 202 and 204 together. Springs 209 may also be
provided to facilitate opening of adaptor 200.
[0109] A groove 240 separates first half 202 from second half 204
when the halves are closed and clip 230 is secured. Groove 240 is
of sufficient width to accept the proximal end of a catheter having
the low profile valve of the present invention, as described in
detail above. A fitting 210 is positioned on half 202, to create an
inflation passageway 212 which terminates in opening 285 on the
interior surface of first half 202. Fitting 210 is preferably a
standard luer connector which may be attached to a variety of
existing external pressurized fluid sources, although other types
of fittings, such as tubings, quick connects, and Y-site
connections, may be easily substituted for a luer fitting.
[0110] A seal comprising a pair of gaskets 280 is positioned around
opening 285 on the interior surfaces of halves 202 and 204. Gaskets
280 are in alignment, such that when halves 202 and 204 are brought
together and secured by locking clip 230, a fluid tight inflation
chamber is created within the interior region defined by gaskets
280. The fluid tight inflation chamber is in fluid communication
with fitting 210 via inflation passageway 212, so that a
pressurized inflation fluid may be introduced into the fluid tight
inflation chamber by attaching an external pressurized fluid source
to fitting 210. Moreover, gaskets 280 are preferably formed of
resilient materials, such as silicone, C-FLEX (TM) and PEBAX (TM),
so that gaskets 280 may form-fit over a catheter tubular body which
extends across the lateral edges of gaskets 280, to create the
fluid tight chamber.
[0111] An actuator 220 is positioned on the external surface of
half 202. In the embodiment illustrated in FIGS. 8 and 9, actuator
220 controls a cam which operates a sliding panel 283 on the
interior surface of half 202. Sliding panel 283 moves back and
forth along a line which bisects opening 285. When actuator 220 is
moved to a first position, sliding panel 283 moves toward opening
285 along this line. When actuator 220 is moved to a second
position, sliding panel 283 moves away from opening 285 along the
same line. A corresponding sliding panel 284 is positioned on half
204, such that panels 283 and 284 are aligned and move together
when the position of actuator 220 is changed. To facilitate
coordinated movement of panels 283 and 284, a pin 286, or such
other similar engagement structure, may be provided to releasably
secure panel 283 to panel 284 when the adaptor is closed. The
length of travel of panels 283 and 284 is preferably adjusted to
provide the minimum sufficient distance to position the sealing
member in the valve open or valve closed position, as desired.
[0112] Panels 283 and 284 each have a roughened surface 290, to
facilitate the frictional engagement of panels 283 and 284 with the
main shaft portion of the low profile valve. In a preferred
embodiment, panels 283 and 284 are both made of silicone, and
roughened surface 290 comprises teeth 291 and grooves 292 formed on
each of panels 283 and 284. The teeth 291 and grooves 292
cooperate, to permit the teeth of one panel to fit into the grooves
of the opposite panel when the adaptor is closed.
[0113] For ease of understanding, the operation of inflation
adaptor 200 to inflate the balloon of the catheter of FIGS. 1-3
will now be described. Actuator 220 is moved to the first position,
so that sliding panels 283 and 284 are moved closer to opening 285.
Locking clip 230 is then undone, exposing groove 240. Halves 202
and 204 are then partially separated, and catheter 10, with the
balloon 20 deflated, is inserted into the inflation adaptor. As
described previously, catheter 10 has an inflation port 22 located
near proximal end 12, and a main shaft 33 extending from proximal
end 12. Catheter 10, with the low profile valve in the closed
position, is placed within groove 240 of partially open adaptor
200, and catheter 10 and main shaft 33 are placed within securing
clips 271 and 272, such that when halves 202 and 204 are closed,
inflation port 22 will lie within the fluid tight inflation chamber
created by gaskets 280, and the extending portion of main shaft 33,
but not proximal end 12, will rest between sliding panels 283 and
284. An alignment slot 298 and overlying shelf 299 may be provided
to facilitate alignment and prevent buckling or kinking of the
catheter and sealing member during use.
[0114] As shown in FIG. 9B, in one embodiment, indicia 260 are
provided on catheter 10 and main shaft 33, which when aligned with
indicia 270 on inflation adaptor 200, result in alignment of
inflation port 22 with the fluid tight inflation chamber of adaptor
200, and alignment of main shaft 33 with sliding panels 283 and
284, when catheter 10 and sealing member 30 are inserted into
groove 240. Indicia 260 and 270 may take the form of markings,
grooves or notches, or any other suitable means of aligning the
valve with the inflation adaptor alignment indicia, may be
provided. Preferably, the gap between indicia 260 on catheter 10
and main shaft 33 is approximately equal to the space between clips
271 and 272, such that by placing indicia 260 within clips 271 and
272, catheter 10 and main shaft 33 are properly aligned within
adaptor 200.
[0115] Indicia solely on the catheter tubular body may also be used
to facilitate correct alignment. For example, two visible markings
may be place on the catheter on either side of the catheter
inflation access port. By inserting the catheter into lower half
204 so that both of these markings are place within lower half
gasket 280, the catheter inflation access port will be within the
fluid tight inflation chamber created by gaskets 280 when halves
202 and 204 are secured to one another.
[0116] Once main shaft 33 and inflation port 22 are properly
aligned within adaptor 200, locking clip 230 is secured. Inflation
port 22 now lies within the fluid tight inflation chamber created
by gaskets 280, and main shaft 33 rests between sliding panels 283
and 284. The clinician may then attach an external pressurized
fluid source to fitting 210.
[0117] To inflate balloon 20, the clinician moves actuator 220 from
the first position to the second position, thereby causing sliding
panels 283 and 284 to move away from opening 885. Because main
shaft 33 is firmly secured between panels 283 and 284, a
longitudinal force directed away from proximal end 12 is applied to
main shaft 33. The longitudinal force on main shaft 33 results in
wire 32 being partially withdrawn from lumen 40, which causes
sealer portion 36 on wire 32 to be moved to a position within lumen
40 which is proximal of inflation port 22. The movement of sealer
portion 36 proximally of inflation port 22 opens the low profile
valve, by establishing an unrestricted fluid pathway between
inflation port 22 and balloon 20.
[0118] The external pressurized fluid source may then be activated,
as for example by pushing the plunger on a syringe, such that
pressurized fluid passes through passageway 212 and opening 285
into the fluid tight inflation chamber. The pressurized fluid then
passes through inflation port 22 and lumen 40, to inflate balloon
20.
[0119] Inflated balloon 20 may be maintained in the inflated state,
in the absence of the pressurized fluid source, by closing the low
profile valve. This is accomplished by moving actuator 220 back to
the first position, thereby causing sliding panels 283 and 284 to
move toward opening 285. The moving panels apply a longitudinal
force, directed toward proximal end 12 to main shaft 33, causing
wire 32 to be further inserted into lumen 40. Consequently, sealer
portion 36 is moved from a position within lumen 40 which is
proximal to inflation port 22 to a position in lumen 40 which is
distal to inflation port 22. The fluid tight seal created by sealer
portion 36 traps the pressurized fluid within lumen 40 and balloon
20, thereby maintaining balloon 20 in the inflated state. The
external pressurized fluid source may then be deactivated and
removed. Once the low profile valve is closed, inflation adaptor
200 may be removed by unlocking clip 230, and removing catheter 10
and main shaft 33 from groove 240.
[0120] Referring to FIGS. 10 and 11, there is illustrated an
alternative embodiment of an inflation adaptor especially adapted
for manipulating removable low profile valves, although it may be
used with side-access embodiments as well. Moreover, it should also
be appreciated that adaptor 200 and similar type adaptors may also
be used to manipulate removable valve embodiments.
[0121] Adaptor 300 comprises an outer sleeve 320 formed of metal,
medical grade polycarbonate, or similar such materials. Outer
sleeve 300 defines a tapering inner lumen 350. Lumen 350 tapers
from large diameter 352 which is significantly greater than the
outer diameter of the catheter tubular bodies inserted into lumen
350, to a smaller diameter 355, which is slightly larger the outer
diameter of the catheter tubular body. Lumen 350 is in fluid
communication with an inflation passageway 312 formed by fitting
310, so that a pressurized inflation fluid may be introduced into
lumen 350. Releasable seals 315 are positioned at each end of lumen
350, such as to create a fluid tight inflation chamber within lumen
350 when a pressurized fluid source is attached. Releasable seals
350 may comprise any type of seal known to those of skill in the
are, such as Toughy Borst connectors, hemostatic valves, and the
like. Releasable seals 350 may also act to secure any catheters and
sealing members inserted within the releasable seal openings 325 In
use, a catheter and sealing member, such as that described in
connection with FIGS. 6-7, is inserted into opening 325 after seals
315 have been opened. The catheter and sealing member are
positioned under passageway 312, and the sealing member is removed
from the proximal opening of the catheter. A fluid passageway is
thereby created between the proximal catheter opening and the
expandable member of the distal end of the catheter. Seals 350 are
closed to create a fluid tight chamber, and a vacuum and/or
pressurized inflation fluid is applied, to inflate or deflate the
balloon. After the desired inflation or deflation has occurred, the
sealing member may be introduced into the proximal opening of the
catheter tubular body to seal the lumen, either by hand or by a
movable actuator (not shown). Seals 350 may then be loosened, and
the end access adaptor 300 removed by sliding the adaptor off the
end of the catheter and sealing member.
[0122] Referring to FIGS. 16-18B, there is illustrated an
alternative embodiment inflation adaptor 800 which may also be used
in conjunction with the low profile valves of the present
invention, of the type depicted in FIGS. 1-5, to inflate or deflate
catheter balloons. Inflation adaptor 800 comprises a housing having
a first half 802 and a second half 804, which are preferably formed
of a medical grade polycarbonate. However, as will be appreciated
by those of skill in the art, a great many other materials may by
used to form adaptor 800, including metals such as 300 series
stainless steel and 400 series stainless steel, and polymeric
materials such as Acrylonitrile-butadiene-styrene (ABS), Acrylics,
and Styrene-acrylonitriles. Furthermore, the individual halves 802
and 804 may be manufactured in a variety of different ways. For
example, where polymeric materials are used, it is preferable to
use a mold to manufacture each of the halves. Moreover, in some
embodiments, more than one molded piece may be used to form an
individual half, with the various pieces being joined together by
bonding or mechanical means to form a half. Alternately, as is
known in the art, the individual halves can be formed through
machining processes performed on larger blocks of the raw
materials.
[0123] Halves 802 and 804 are attached to one another by hinges 806
positioned on one of the lateral edges of each half, through which
a joining pin 805 is inserted, such that halves 802 and 804 may be
opened or closed in a clam shell manner as depicted in FIGS. 16 and
17. Preferably, the cross-sectional angle formed by halves 802 and
804 in the open position, as shown in FIG. 17, is 90.degree. or
greater, and more preferably from 120.degree.-180.degree., to
facilitate insertion of a catheter into adaptor 800.
[0124] As shown in FIGS. 16 and 17, a plate 832 is secured to the
front portion of housing half 804 by three screws 833. Plate 832 is
provided with two or more pin receptacles 834. A cam latch 830 is
mounted on plate 832 and is secured thereto by pin 831 which runs
through pin receptacles 834 and a corresponding cam latch pin
receptacles 836, to form a hinge between cam latch 830 and plate
832. Cam latch 830 and plate 832 may be made from any of the same
variety of materials as housing halves 802 and 804, and for any
particular embodiment, are preferably made of identical materials,
although combinations of materials may also be used. Also, as is
appreciated by those of skill in the art, the corresponding hinge
structure provided by plate 832 and cam latch 830 may also be
achieved by many other methods. For example, plate 832 may be
integrally molded with housing half 804 at the time of manufacture
as a single piece, thereby eliminating the need for screws 833, but
with cam latch 830 mounted thereon as described above.
[0125] Cam latch 830 is designed to secure halves 802 and 804
together when adaptor 800 is in use, to assist in the creation of
an the inflation seal as described above. Advantageously, by
placing cam latch on half 804 as shown, the adaptor interior is
more accessible to the clinician during a procedure, and it is
easier for the clinician to insert catheters into adaptor 800. Cam
latch 830 also serves the important function of preventing
accidental opening of the adaptor 800 during use. An important
feature of cam latch 830 is the manner in which it cooperates with
housing half 802 to create a releasable locking mechanism which
applies great force to halves 802 and 804 upon closing, while at
the same time using the principles of mechanical advantage to
minimize the force the user must exert to close cam latch 830. This
is achieved by providing latch 830 with a cammed surface 838 and
also providing the front edge of housing half 802 with a rounded
lip 837 to accept cammed surface 838, as shown in cross-sectional
schematic form in FIGS. 19A-19C.
[0126] Referring to FIG. 19A, halves 802 and 804 have been brought
together, with cam latch 830 in its open position. As cam latch 830
begins to be closed, as shown in FIG. 19B, cammed surface 838
contacts rounded lip 837 and exerts a closing force thereon. Upon
further closing, and to the fully closed position shown in FIG.
19C, cam latch 830 acts as a lever, with the closing force between
cammed surface 838 and lip 837 being a function of the force of
exerted by the user, the length of the lever (length of cam latch
door), and the height of the cam surface, as defined by the
following well known mathematical equation: 1 F u = F c H L F u =
User applied force F c = Closing force L = length of lever ( width
of door ) H = height of cam
[0127] However, as can be appreciated, because the lever length,
which in the adaptor embodiment is the length of cam latch 830 in
its closing direction, is much greater than the height of the cam
created by surface 838 and lip 837, the closing force exerted is
always greater than the force the user exerts on cam latch 830.
Thus, very tight seals may easily be created by the clinician when
the device is used.
[0128] Cam latch 830 is also preferably provided with a shelf 835
to secure halves 802 and 804 together. Shelf 835 is positioned on
latch 830 at a point such that when latch 830 is in its closed
position, shelf 835 firmly contacts housing half 802 along the side
bearing hinges 806. Preferably, shelf 835 has an angled leading
edge to facilitate closing of latch 830.
[0129] A gap 840 separates first half 802 from second half 804 when
the halves are closed and latch 830 is secured. Gap 840 is of
sufficient width to accept the proximal end of a catheter having
the low profile valve of the present invention, as described in
detail above, without crimping the catheter to impair its function.
A fitting 810 is positioned on half 802, to create an inflation
passageway 812 which terminates in opening 885 on the interior
surface of first half 802. Fitting 810 is preferably a standard
luer connector which may be attached to a variety of existing
external pressurized fluid sources, although other types of
fittings, such as tubings, quick connects, and Y-site connections,
may be easily substituted for a luer fitting.
[0130] A seal comprising a pair of gaskets 880 is positioned around
opening 885 on the interior surfaces of halves 802 and 804. Gaskets
880 are in alignment, such that when halves 802 and 804 are brought
together and secured by cam latch 830, a fluid tight inflation
chamber is created within the interior region defined by gaskets
880. The fluid tight inflation chamber is in fluid communication
with fitting 810 via inflation passageway 812, so that a
pressurized inflation fluid may be introduced into the fluid tight
inflation chamber by attaching an external pressurized fluid source
to fitting 810. Gaskets 880 are preferably formed of resilient
materials, such as silicone, C-FLEX (TM) and PEBAX (TM) or KRATON
(TM), silicone, and other elastomeric materials, so that gaskets
880 may form-fit over a catheter tubular body which extends across
the lateral edges of gaskets 880, to create the fluid tight
chamber.
[0131] An actuator 820 is positioned on the external surface of
half 802. In the embodiment illustrated in FIGS. 16-18B, actuator
820 is a rotatable knob controlling a cam which operates a sliding
panel 883 on the interior surface of half 802. As will be
appreciated by those of skill in the art, however, a great many
different actuating structures other than rotatable knobs and
sliding panels may be used to achieve the movement of the catheter
sealing members described herein. Furthermore, where catheter
valves of the present invention require rotational movement, such
as those of FIGS. 12 and 13, rotational actuating mechanisms may be
provided as well.
[0132] Sliding panel 883 moves back and forth along a line which
bisects opening 885. When actuator 820 is moved to a first
position, shown in FIG. 18A, sliding panel 883 moves away from
opening 885 along this line. When actuator 820 is moved to a second
position, as shown in FIG. 18B, sliding panel 883 moves toward
opening 885 along the same line. A corresponding sliding panel 884
is positioned on half 804, such that panels 883 and 884 are aligned
and move together when halves 802 and 804 are closed and the
position of actuator 820 is changed.
[0133] In actual clinical practice, the movement of panels 883 and
884 results in the opening and closing of a catheter valve placed
within adaptor 800. When actuator 820 is moved to the position
shown in FIG. 18A, panels 883 and 884 move away from opening 885.
This would result in the opening of the valve described in
connection with FIGS. 1-5, as the sealer portion of the valve would
be positioned proximally of the access port to establish a fluid
pathway between the access port and the inflatable balloon at the
distal end of the catheter. Conversely, when actuator 820 is moved
to the position shown in FIG. 18B, panels 883 and 884 move toward
opening 885. This would result in the closing of the valve, as the
sealer portion of the valve would be positioned distally of the
access port, thereby preventing substantially all fluid flow
between the access port and those portions of the catheter distal
to the sealer portion. Preferably, detents (not shown) are provided
on the actuator camming mechanism to provide the user with tactile
and audible feedback when the panels are nearest or farthest from
opening 885 (i.e., catheter valve is closed or open,
respectively).
[0134] Adaptor 800 is also preferably provided with a safety lock,
to prevent accidental opening when the adaptor is being used and
the catheter valve is open. As shown in FIG. 18A and 18B, this may
be achieved by providing an extending flanged portion 822 to
actuator knob 820. When actuator knob 820 is in the valve open
position, as shown in FIG. 18A, extending flange 822 extends over
latch 830, preventing the latch from being opened. In the valve
closed position, as shown in FIG. 18B, flange 821 is rotated away
from latch 830, which may then be opened.
[0135] Panels 883 and 884 each have a roughened surface 890, to
facilitate the frictional engagement of panels 883 and 884 and
their coordinated travel with the moving portions of the low
profile valve. Panels 883 and 884 may be made from any of a variety
of polymeric or metallic materials, but must possess sufficient
frictional force to engage and move the catheter sealing member
without slippage. Consequently, depending on the type of catheter
used, those of skill in the art may desire to select different
materials for panels 883 and 884 to maximize the frictional forces
between the panels and their intended use catheter. In a preferred
embodiment, in which panels 883 and 884 are to engage a catheter
sealing member made from stainless steel, panels 883 and 884 are
both made of KRATON 90A (TM), and roughened surface 890 comprises
teeth 891 and grooves 892 formed on each of panels 883 and 884. The
teeth 891 and grooves 892 cooperate, to permit the teeth of one
panel to fit into the grooves of the opposite panel when the
adaptor is closed. Furthermore, alternative cooperating structure,
such as dimples and ridges, may also be used to coordinate travel
of panels 883 and 884.
[0136] One problem that has been recognized with low profile valves
of the present invention is the phenomenon of plug walk-out. That
is, after the valve has been placed in its closed position, with
the sealer portion of the sealing member distal to the inflation
access port, and the adaptor removed, the internal forces on the
sealing member tend to cause very small portions of the sealing
member to be pushed out of the catheter proximal end. Plug walk out
is undesirable as it has an adverse impact on the ability of the
sealed catheter to act as a guidewire for other devices. It has
been found, however, the plug walk out can be minimized or
eliminated if the sealing member is initially "overdriven", or
forced slightly further in the catheter, during the sealing
step.
[0137] Advantageously, adaptor 800 is provided with an overdrive
system to overdrive a sealing member into a catheter. Referring to
FIG. 17, panel 884 travels back and forth within housing recess 894
along a which bisects opening 885, as described above. A spring 809
is mounted in recess 894 and is attached to the wall of recess 894
and panel 884. Spring 809 is biased so as to push panel 884 toward
opening 885, and forces panel 884 against the wall of recess 894
which is opposite to that which spring 809 is attached.
[0138] Referring to FIGS. 20A-C, there is shown the top portion of
half 802 containing panel 883. Panel 883 resides in housing recess
893, and travels back and forth along a line which bisects opening
885, as described above. The movement of panel 883 is controlled by
actuator 820, as described above. An expanded spring 888 is
attached to panel 883, as shown in FIGS. 20A-C. Spring 888 has a
strength which exceeds that of lower spring 809. In the adaptor
open position, as shown in FIG. 17, expanded spring 888 contacts
the wall of recess 893, and pushes panel 883 away from the recess
wall to create an overdrive gap 886, as shown in FIG. 20A.
[0139] When a catheter with a valve in a closed position is loaded
into half 804, and halves 802 and 804 are closed and latched, the
teeth 891 of panel 883 contact the grooves of panel 884. The
superior spring force of spring 888 then forces spring 809 to
compress a small amount, such that panel 884 no longer is forced
against the recess wall, and now has an overdrive gap (not shown)
approximately equal to overdrive gap 886. The actuator may then be
engaged to drive panels 883 and 884 away from opening 885 toward
recess walls 893a and 894a, respectively, thereby opening the valve
mechanism. The inflatable balloon on the catheter may then be
inflated as described above.
[0140] Upon closure of the valve, by rotating actuator 820 in the
opposite direction, panels 883 and 884 are moved toward opening 885
until the sealer portion of the sealing member is distal to the
catheter inflation access port. Overdrive of the sealing member is
then achieved when actuator 820 is adjusted so that panels 883 and
884 are forced against recess walls 893b and 894b, as shown for
panel 883 in FIG. 20C. That is, the force of actuator 820 overcomes
the force of spring 888, and drives the sealing member into the
catheter by a distance farther than it initially resided before the
valve was opened, the distance being approximately equal to the
width of gap 886. It has been found that by overdriving the sealing
member to a closed position further than its initial closed
position compensates for plug walk-out. Preferably, the sealing
member is overdriven by a distance of about 0.020 inches.
[0141] Alternative overdrive mechanisms may be used for other
adaptor embodiments. For example, rather than mounting spring 888
on panel 883, the spring might be mounted in a slot wall 893b, with
a plunger (not shown) attached to panel 883 and aligned with the
spring. In its unforced state, the spring would exert force on the
plunger, pushing panel 883 away from wall 893a to create overdrive
gap 896. However, as before, the actuator mechanism 820 could be
used to overcome the spring force in the valve closing cycle,
thereby creating the overdrive. Numerous other overdrive mechanisms
may also be employed, as will be appreciated by those of skill in
the art.
[0142] As illustrated in FIG. 17, adaptor 800 is also provided with
immovable pads 870 on both halves 802 and 804. Pads 870 function to
secure the catheter within adaptor 800 when it is closed, and to
prevent movement of the catheter during valve opening and valve
closing procedures. Accordingly, the material used for pads 870 is
selected to have a high degree of frictional force with respect to
the surface of the catheter body to which pads 870 will contact. A
wide variety of polymeric and metallic materials are thus suitable
to form pads 870 such as KRATON (TM), C-FLEX (TM) or PEBAX (TM). In
one embodiment, pads 870 are integrally molded with halves 802 and
804 out of medical grade polycarbonate, and are intended to contact
a catheter tubular body formed from nitinol.
[0143] It is also preferred that half 804 be provided with guiding
means to facilitate correct positioning of the catheter into the
adaptor. For the embodiment illustrated in FIG. 17, these guiding
means consist of two or more clips 896 to facilitate positioning of
a catheter into the adaptor. Clips 896 are provided with grooves
897 in which the catheter is inserted and secured prior to closure
of adaptor 800. Clips 896 may be formed of any material flexible
enough to be capable of releasably securing the catheters to be
used in adaptor 800. In one preferred embodiment, clips 896 are
formed of C-FLEX 70A (TM). On half 802, and aligned with clips 896,
there are provided recesses 895, to accept clips 896 when halves
802 and 804 are brought together and closed. Preferably, alignment
indicia on the catheters to be used with adaptor 800 coincide with
the spacing of clips 896, so that by placing the catheter portion
bearing the indicia directly in clips 896, the catheter is properly
inserted in the adaptor with its inflation access port contained in
the fluid tight inflation chamber created by gaskets 880 upon
closure of adaptor 800. A projecting ridge 875 may also be provided
to facilitate placement of the catheter, and direct its orientation
during placement in the adaptor so that alignment is proper.
[0144] Alternately, other guiding means may be used as well. For
example, clips 896 may comprise one or more magnetic elements which
cooperate with gold-plated stainless steel rings (or other plated
ferromagnetic substances) incorporated into the catheter tubular
body to guide the catheter into the correct alignment position.
[0145] In one preferred embodiment, as shown in FIG. 17, halves 802
and 804 are also provided with projecting shelves 898 and 899,
respectively, which come together when halves 802 and 804 are
closed to form a slot therebetween in which the catheter resides.
Advantageously, the slot created by shelves 898 and 899 acts to
provide reinforcement to a catheter used in adaptor 800 during the
valve opening and closing procedures, and helps to prevent buckling
or kinking of the catheter tubular body when panels 883 and 884 are
moved to open or close the catheter valve.
[0146] In clinical practice, there is a direct correlation between
the distance that panel 884 moves and the distance moved by the
sealer portion of a catheter valve when adaptor 800 is used.
Consequently, a controlled and known movement of panel 884 over a
set direction and distance results in a movement of the valve
sealer portion in the same direction and for substantially the same
distance. Thus, with a controlled movement adaptor such as adaptor
800, there is no need to require a catheter having positive
cooperating stops to prevent removal of the sealer portion from the
catheter, as was described for the catheter of FIGS. 1-5. The
adaptor itself prevents accidental withdrawal of the sealer portion
from the catheter, by precisely controlling the movement of the
sealer portion within the catheter.
[0147] Accordingly, in one preferred embodiment, adaptor 800 is
used with catheter 900, which lacks positive cooperating stops, and
is depicted in FIGS. 21 and 22. Catheter 900 has a tubular body 918
and inflatable balloon (not shown) as described above. Catheter 900
may be formed of materials and methods as described above, and may
have structural aspects identical to those described previously,
except where otherwise noted.
[0148] Catheter 900 has a proximal end 912, and a distal end (not
shown) to which is mounted an inflatable balloon. A central lumen
940 extends within tubular body 918 between the proximal and distal
ends. An opening 923 to lumen 940 is present at the proximal end
912 of catheter 900. A side-access port 922 in fluid communication
with lumen 940 is provided on tubular body 918.
[0149] A sealing member 930 is inserted into lumen 940 through
central lumen opening 923. Sealing member 930 has a first region
935 which has an outer diameter substantially the same as the outer
diameter of the proximal end 912 of catheter tubular body. Region
935 has a taper 934, reducing in diameter to a second region 933
which has an outer diameter less than the inner diameter of lumen
940. Region 933 tapers over length 931 to form a plug mandrel wire
932. As a consequence, region 933 and plug mandrel wire 932 are
slidably insertable into the proximal opening 923 of catheter 900
and may freely move within lumen 940. In one preferred embodiment,
region 935 has an outer diameter of about 0.013 inches, region 933
has an outer diameter of about 0.0086 inches, and plug mandrel wire
has a diameter of about 0.005 inches, with region 933 and plug
mandrel wire 932 being inserted into a catheter having a central
lumen 940 with an inner diameter of about 0.009 inches.
[0150] The length of sealing member region 935 extending proximally
of catheter 900 may vary in length depending upon the intended use
environment. For example, where catheter 900 is to be used as a
guide for other catheters in an "over-the-wire" embodiment, it is
preferred that the total length of catheter 900 and sealing member
region 935 be about 300 centimeters. Alternately, where catheter
900 is to be used in a single operator or rapid exchange
embodiment, it is preferred that the total length of catheter 900
and region 935 be about 180 centimeters. Accordingly, with a known
catheter length and use environment, an appropriate length for
region 935 may be chosen.
[0151] The elements of sealing member 930 may be formed of
materials and by methods as described previously. For example,
regions 935 and 933 and plug mandrel wire 932 may all be made out
of metals such as stainless steel. Alternately, combinations of
materials may be used as well. For example, in some applications it
may be desirable to manufacture regions 935 and 933 out of
stainless steel, while manufacturing plug mandrel wire 932 out of
nitinol. Furthermore, the various sealing member regions may be
made from a single metal wire strand coined at various points to
achieve the desired dimensional tolerances, or multiple segments
may be joined together to form sealing member 930.
[0152] Where multiple segments are joined, region 935, region 933,
and plug mandrel wire 932 are attached to one another by any
suitable means of bonding metal to metal, such as soldering,
brazing, adhesives and the like. In one preferred embodiment,
cyanoacrylate adhesives are used to adhere these various parts of
sealing member 930 to one another.
[0153] As illustrated in FIGS. 21 and 22, the outer diameter of
sealing member region 933 is less than the inner diameter of lumen
940, such that region 933 is slidably insertable into lumen 940. In
addition, the outer diameters of the tapered portions 931 and wire
932 are also small enough such that they too are slidably
insertable in lumen 940. However, the outer diameter of region 935
is greater than the inner diameter 940, and thus only a small
portion of tapered portion 934 of sealing member 930 between region
935 and region 933 is insertable into lumen 940 through opening
923. Advantageously, this provides for a snug interference fit when
sealing member 930 is fully inserted into catheter 900. This
interference fit provides a frictional force which counteracts the
tendency of the pressurized fluids and internal wire flexing in the
catheter to push sealing member 930 out of opening 923.
[0154] As illustrated in FIGS. 21 and 22, sealing member 930 has
movement-force increasing structure which increases the force
required to move sealing member 930 within lumen 940. The
movement-force increasing structure consists of waves 938a and 938b
formed in wire 932 near its distal end. Waves 938a and 938b contact
the inner surface of lumen 940, thereby increasing the frictional
force which must be overcome to move wire 932 within lumen 940. In
one preferred embodiment, where wire 932 is made of nitinol and has
an outer diameter of about 0.005 inches, and is inserted into a
nitinol catheter which has an inner lumen 940 with a diameter of
about 0.090 inches, waves are formed on wire 932 for 11/2 cycles
with an amplitude of about 0.016 inches to increase the
valve-opening movement force.
[0155] A lumen sealer portion 936 is coaxially and fixedly mounted
on wire 932. Sealer portion 936 forms a fluid tight seal with the
outer diameter of wire 932 and the inner diameter of lumen 940,
such that fluid introduced into lumen 940 through side-access port
922 is prevented from flowing past sealer portion 936 when sealer
portion 936 is inserted into lumen 940 distally of side-access port
922. Sealer portion 936 forms the fluid tight seal by firmly
contacting the entire inner circumference of a section of lumen 940
along a substantial portion of the length of sealer portion 936,
and may be formed of materials and by methods as previously
described.
[0156] As shown in FIG. 21, sealer portion 936 is positioned
proximally of side-access opening 922, so that an unrestricted
fluid passageway exists between port 922 and the inflatable balloon
at the distal end of catheter 900. This is the valve open position
described above. In this position, region 933 is shown partially
withdrawn from opening 923. Referring to FIG. 22, sealer portion
936 is positioned distally of port 922, so that fluid flow between
port 922 and the inflatable balloon at the distal end of catheter
900 are substantially blocked. This is the valve closed position
described above.
[0157] Catheter 900 is changed from the valve open position to the
valve closed position by the movement of sealing member 930 and its
various components. Preferably, the exact length of movement needed
to change catheter 900 from the valve closed to the valve open
position is built into the movement function of the adaptor used to
manipulate sealing member 930 thereby opening and closing the
catheter valve. In this regard, it is preferred that catheter 900
be used with an adaptor such as adaptor 800, which provides for
such controlled precise movement.
[0158] The "stroke-length", or overall movement in one dimension,
of sealing member 930 required to open or close the valve may be
varied depending upon the catheter requirements. When relying upon
the inflation adaptor to control movement, however, it is important
that the movement of the controlling elements of the adaptor be
coordinated with those of sealing member 930. With respect to
adaptor 800, this is accomplished by selecting a recess 893
dimension which precisely defines the distance that sealing member
930 is to travel to achieve the valve open and valve closed
positions, without accidentally removing sealing member 930 from
opening 923. In one embodiment, where access port 922 is positioned
36 mm from opening 923, a stroke length of 5.5 mm was found to be
suitable.
[0159] It will be appreciated that certain variations of the
present invention may suggest themselves to those skilled in the
art. The foregoing detailed description is to be clearly understood
as given by way of illustration, the spirit and scope of this
invention being limited solely by the appended claims.
* * * * *