U.S. patent application number 09/769312 was filed with the patent office on 2001-07-12 for vascular filtering device.
Invention is credited to Kanesaka, Nozomu.
Application Number | 20010007947 09/769312 |
Document ID | / |
Family ID | 23685660 |
Filed Date | 2001-07-12 |
United States Patent
Application |
20010007947 |
Kind Code |
A1 |
Kanesaka, Nozomu |
July 12, 2001 |
Vascular filtering device
Abstract
A vascular filtering device is formed of a flexible shaft having
a passageway extending inside the shaft, an inflatable member
communicating with the passageway and having a spiral form, and a
filter member fixed to the distal end portion of the shaft. The
inflatable member is attached at an inner side thereof to a distal
end portion of the shaft. The filter member is attached to the
shaft and fixed onto the outer side surface of the inflatable
member along the entire length thereof. When the inflatable member
is inflated, the filter member is enlarged to allow a blood
containing debris or blood clots to flow through the filter member.
Thus, the debris or blood clots are captured by the filter member.
When the inflatable member is deflated, the filter member is
disposed close to the side surface of the shaft. Thus, the filter
member with the debris or clots can be easily removed from the
blood vessel.
Inventors: |
Kanesaka, Nozomu; (Old
Tappan, NJ) |
Correspondence
Address: |
KANESAKA AND TAKEUCHI
1423 Powhatan Street
Alexandria
VA
22314
US
|
Family ID: |
23685660 |
Appl. No.: |
09/769312 |
Filed: |
January 26, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
09769312 |
Jan 26, 2001 |
|
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|
09425218 |
Oct 22, 1999 |
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Current U.S.
Class: |
606/200 ;
606/198 |
Current CPC
Class: |
A61F 2002/068 20130101;
A61B 17/22032 20130101; A61F 2/0105 20200501; A61F 2230/0006
20130101; A61F 2250/0003 20130101 |
Class at
Publication: |
606/200 ;
606/198 |
International
Class: |
A61M 029/00 |
Claims
What is claimed is:
1. A vascular filtering device, comprising: a flexible shaft having
a side surface, a passageway extending inside the flexible shaft,
and a side opening formed in the side surface at a distal end
portion of the shaft and communicating with the passageway, an
inflatable member having a spiral form and attached to the distal
end portion of the shaft to communicate with the passageway through
the side opening of the shaft, said inflatable member having an
outer side surface, and an inner side surface entirely fixed to the
side wall of the shaft, and a filter member having a distal end
sealingly fixed to the distal end portion of the shaft and an open
end at a side opposite to the distal end thereof, said filter
member extending along the flexible shaft and fixed onto the outer
side surface of the inflatable member along an entire length
thereof so that when the inflatable member is inflated, the filter
member is enlarged to allow a foreign substance to enter into the
filter member through the open end, and when the inflatable member
is deflated, the filter member is disposed close to the side
surface of the shaft.
2. A vascular filtering device according to claim 1, wherein said
shaft is a guide shaft for allowing a vascular treatment device to
be transferred in a blood vessel.
3. A vascular filtering device according to claim 1, wherein said
filter member has a bag shape opening toward a proximal end portion
of the shaft.
4. A vascular filtering device according to claim 1, wherein said
inflatable member has a tubular shape with a hollow portion therein
extending substantially throughout an entire length thereof, said
hollow portion having a diameter gradually enlarging from the
distal end of the shaft.
5. A vascular filtering device according to claim 1, wherein said
shaft includes a partition wall therein, and a port in the side
wall near the partition wall, said partition wall dividing the
passageway into a first passageway extending from a proximal end
portion of the shaft to the opening to communicate with the
inflatable member, and a second passageway extending from the port
to a distal end of the shaft to allow a guide wire to pass
therethrough.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This is a continuation in part application of Ser. No.
09/425,218 filed on Oct. 22, 1999.
BACKGROUND OF THE INVENTION AND RELATED ART STATEMENT
[0002] The present invention relates to a device for capturing a
debris or blood clots in a blood vessel, and more particularly, it
relates to a vascular filtering device for capturing and removing
the debris or blood clots used in, e.g. percutaneous transluminal
coronary angioplasty (PTCA) procedure.
[0003] In recent years, an inter-vascular treatment, such as PTCA,
has been widely practiced for a treatment of stenosis in the
artery. In the PTCA procedure, a catheter which is provided with a
balloon at a distal end thereof is inserted into a blood vessel
which has a stenosis, and the balloon is inflated to enlarge the
stenosis. Also, after enlarging the stenosis, a stent may be
provided for preventing re-stenosis.
[0004] In performing the PTCA procedure, however, it may cause
other problems. Namely, debris or blood clots formed at the
stenosis may be separated from the portion at the stenosis and
migrate to other critical area, such as brain and pulmonary
arteries, while the PTCA procedure is being performed.
[0005] In order to remove the debris or blood clots while the PTCA
procedure is being performed, a device having a mesh or net may be
disposed in the blood vessel, as proposed in U.S. Pat. No.
6,001,118. The net is inflated by various inflating means to catch
emboli, but the net with the emboli may not be smoothly removed
from the blood vessel after use.
[0006] The present invention has been made in view of the above
problem, and an object of the invention is to provide a vascular
filtering device for removing debris or blood clots in the blood
vessel of a patient during an operation, such as balloon dilation
procedure.
[0007] Another object of the invention is to provide a vascular
filtering device as stated above, which can be easily delivered to
a desired location in the blood vessel and removed therefrom after
capturing the debris or blood clots.
[0008] A further object of the invention is to provide a vascular
filtering device as stated above, which is formed easily and is
used as a guide wire or tube for other procedure.
[0009] Further objects and advantages of the invention will be
apparent from the following description of the invention.
SUMMARY OF THE INVENTION
[0010] A vascular filtering device of the invention is basically
formed of a flexible shaft, an inflatable member attached to the
shaft, and a filter member attached to the inflatable member and
the shaft.
[0011] The flexible shaft has a side surface, a passageway
extending inside the flexible shaft, and a side opening formed in
the side wall at a distal end portion of the shaft to communicate
with the passageway. A fluid may be supplied to the passageway from
a proximal end of the shaft.
[0012] The inflatable member has a spiral or helical form and is
attached to the distal end portion of the shaft to communicate with
the passageway through the side opening of the shaft. The
inflatable member has an outer side surface, and an inner side
surface entirely fixed to the side wall of the shaft not to be
separated therefrom.
[0013] The filter member has a distal end sealingly fixed to the
distal end portion of the shaft and an open end at a side opposite
to the distal end. The filter member extends along the flexible
shaft to cover the distal end portion thereof and is fixed onto the
outer side surface of the inflatable member along an entire length
thereof. Thus, when the inflatable member is inflated by providing
the liquid to the inflatable member through the passageway, the
filter member is enlarged to allow a foreign substance, such as
blood clots and debris, to enter into the filter member through the
open end to capture the same. When the inflatable member is
deflated by forcibly removing the liquid from the inflatable
member, the filter member with the blood clots and debris is closed
or disposed close to the side surface of the shaft. Thus, the
filtering device can be easily removed from the blood vessel.
[0014] When the filtering device of the invention is used, the
inflatable member is made in a fully deflated condition. The distal
end portion of the shaft is inserted into a blood vessel from a
portion used in a regular PTCA procedure, and the shaft is advanced
to a desired location in the blood vessel passing through a portion
to be treated later. Then, a liquid is supplied to the inflatable
member through the passageway to thereby inflate the inflatable
member. Accordingly, the proximal end of the filter member is
opened and is held between an inner wall of the blood vessel and
the inflatable member. Blood in the blood vessel flows along the
inflatable member and passes through the filter member to remove a
foreign substance, such as debris and blood clots.
[0015] In this condition, since the filter and the inflatable
member do not block the blood flow in the blood vessel, a required
PTCA procedure can be made smoothly. If debris or blood clots is
formed by the PTCA procedure and flows in the blood vessel, the
debris or blood clots can be captures by the filter member.
[0016] After the PTCA procedure is finished, the inflatable member
is deflated by forcibly removing the liquid in the inflatable
member. Then, the filter member with the debris blood clots is
removed from the blood vessel together with the shaft.
[0017] In the invention, since the inflatable member is attached to
both shaft and filter member along the entire inner and outer
portions, when the inflatable member is inflated, the filter member
can surely abuts against the inner wall of the blood vessel. When
the inflatable member is forcibly deflated, the filter member is
disposed close to the outer surface of the shaft with the debris or
blood clots therein. Thus, the shaft with the inflatable member and
the filter member can be easily removed from the blood vessel. The
debris or blood clots is removed smoothly together with the filter
member.
[0018] Preferably, the shaft of the filtering device is used as a
guide shaft for allowing a vascular treatment device to be
transferred in a blood vessel, resulting in that the guide shaft
has the filtering member for capturing a foreign substance formed
in the vascular treatment procedure.
[0019] In the invention, the filtering device may be transferred in
the blood vessel through a guide wire. In this case, the shaft
includes a partition wall in the passageway, and a port in the side
wall near the partition wall. The partition wall divides the
passageway into a first passageway extending from the proximal end
portion of the shaft to the opening to communicate with the
inflatable member, and a second passageway extending from the port
to the distal end of the shaft to allow the guide wire to pass
therethrough. The filtering device can be transferred to a desired
location easily and rapidly through the guide wire already disposed
in the blood vessel, as in the balloon catheter system.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is an explanatory view showing a first embodiment of
a vascular filtering device of the invention placed in a blood
vessel; and
[0021] FIG. 2 is an explanatory view showing a second embodiment of
a vascular filtering device of the invention placed in a blood
vessel.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0022] Hereinafter, embodiments of a vascular filtering device of
the present invention will be explained with reference to the
attached drawings.
[0023] As shown in FIG. 1, a first embodiment of the vascular
filtering device 1 is formed of a flexible shaft 2 having a
passageway 3 therein, a tube-like balloon or inflatable member 4
helically wound around a distal end portion of the shaft 2, and a
filter 5 in a substantially conical shape having a distal end 7
attached to the distal end of the shaft 2.
[0024] The shaft 2 may be made of metal or plastics, and has an
elongated shape with flexibility to be inserted into a blood
vessel, as in a regular PTCA device. In the first embodiment, the
shaft 2 is used as a guide wire for a PTCA procedure.
[0025] The passageway 3 of the shaft 2 has an open end (not shown)
at a proximal end of the shaft 2, and is closed at a distal end 6.
The shaft 2 has an opening 8 on the side wall at the distal end
portion of the shaft to communicate with an interior of the balloon
4 for inflating and deflating the balloon 4.
[0026] The balloon 4 is hollow and is spirally or helically wound
around the shaft 2 from a front end 9 at the distal end 6 of the
shaft 2 to a rear end 10 thereof. The diameter of the balloon 4 is
gradually enlarged from the front end 9 to the rear end 10. Also,
the balloon 4 is entirely fixed to the outer surface of the shaft 2
at the inner side thereof along the entire length of the balloon 4.
There is no space between the balloon 4 and the shaft 2. Therefore,
the distance from the outer side of the balloon to the outer
surface of the shaft 2 gradually increases from the front end 9 to
the rear end 10.
[0027] The rear end 10 of the balloon 4 is sealingly connected to
the opening 8 of the shaft 2, so that the passageway 3 communicates
with the interior of the balloon 4. The front end 9 may also be
communicated with the passageway 3.
[0028] Incidentally, the vascular filtering device 1 shown in FIG.
1 is in a condition that the balloon 4 is inflated in the blood
vessel.
[0029] The filter 5 shown in section in FIG. 1 surrounds the
helically wound balloon 4, and is fixed to the entire outside
surface of the balloon 4. Therefore, when the balloon 4 is
inflated, the filter 5 mounted on the balloon 4 is expanded to form
the conical shape as shown in FIG. 1. Also, when the balloon 4 is
deflated, the filter 5 attached to the balloon 4 is disposed close
to the outer surface of the shaft 2.
[0030] A bottom or enlarged portion of the conical shape filter 5
is opened to have an opening 11 shown in the figure, and a
periphery of the opening 8 is partly attached to the balloon 4. The
filter 5 has a thickness of about 0.254 mm (0.001 inch) to 0.508 mm
(0.002 inch), and includes numerous pores for allowing liquid, such
as blood, to pass therethrough. The diameter of each pore is
approximately 6 .mu.m such that certain undesired substances, such
as debris or blood clots, can not pass through the pores of the
filter 5 while red and white blood corpuscles and so on can pass
therethrough.
[0031] In use, the vascular filtering device 1 structured as
described above is prepared such that the balloon 4 and the filter
5 are collapsed. In this condition, the filtering device 1 is
entered into a blood vessel, e.g. vein of a foot, similar to
installing a guide wire into the blood vessel. The shaft is
advanced, and the balloon 4 at the distal end portion of the shaft
2 passes through a treatment portion, e.g. stenosis, by a PTCA
procedure later operated. Then, a liquid is supplied to the balloon
4 through the passageway 3 to inflate the balloon 4 to set the
shaft. As a result, the filter 5 is opened and is held between an
inner wall of a blood vessel 12 and the balloon 4. Thus, the filter
5 is set at a downstream of the blood vessel 12 relative to the
treatment portion. In this condition, since the blood flows along
the path around the balloon 4 and passes through the filter 5, this
condition is kept until the required operation, e.g. PTCA procedure
for opening stenosis and installing a stent, is completed.
[0032] In case debris or blood clots 13 occurs at the upstream side
of the blood vessel 12 during the PTCA procedure, blood containing
the debris or blood clots 13 flows to the downstream of the blood
vessel 12 in a direction shown by arrows in FIG. 1. Blood
containing debris or blood clots 13 flows into the opening 11 of
the filter 5, and flows along the helical path of the balloon 4.
Blood passes through the pores of the filter 5, while the debris or
blood clots 13 is caught inside the conical shaped filter 5 since
they can not pass through the pores of the filter 5.
[0033] After the PTCA procedure is completed, the balloon 4 is
deflated to collapse the filter 5 containing the debris or blood
clots 13 therein by forcibly removing the liquid inside the balloon
4. Since the filter 5 is fixed to the outer surface of the balloon
4, when the balloon 4 is deflated, the filter 5 is also collapsed
and disposed close to the shaft 2 while the debris or blood clots
13 are held between the filter and the shaft 2. Then, the vascular
filtering device 1 is removed from the blood vessel 12 by pulling
the vascular filtering device 1 in a direction opposite to the
direction of the blood flow. Accordingly, the debris or blood clots
13 formed at the PTCA procedure can be removed from the blood
vessel 12.
[0034] In the invention, when the balloon 4 is deflated, the filter
5 is collapsed to be located close to the outer surface of the
shaft 2. Therefore, although the debris or blood clots 13 is caught
by the filter 5, the size of the filter 5 is made small. Thus, the
filtering device 1 of the invention can be removed from the blood
vessel 12 smoothly.
[0035] FIG. 2 shows a second embodiment of the vascular filtering
device 1' of the invention. The vascular filtering device 1' is
designed to be delivered to the proper position in the blood vessel
through a guide wire 14 already placed in the blood vessel, and has
a rapid exchange system.
[0036] Namely, in the filtering device 1', a shaft 2' has a
partition wall 15 therein to divide a passageway into an inflation
passageway 3' for inflating a balloon 4' and a guidewire passageway
16. Also, a guidewire port 17 is provided near the partition wall
15 of the shaft, and the shaft 2' has an opening 6' at a distal end
thereof. The guide wire 14 can pass through the guidewire port 17,
the passageway 15 and the opening 6'. In the vascular filtering
device 1', the balloon 4' has an elongated spiral shape slightly
shorter than that of the balloon 4, and is communicated with the
passageway 3' at one portion.
[0037] In use, an end of the guide wire 14 is inserted into the
passageway 15, and the vascular filtering device 1' is pushed into
the blood vessel 12 along the guide wire 14. After the filtering
device 1' is disposed in the proper position, the balloon 4' is
inflated to open and set the filter 5. Then, the required operation
is carried out, and if debris or blood clots 13 is formed, it is
captured by the filter 5. In this embodiment, in case the vascular
filtering device 1' is to be exchanged, the vascular filtering
device 1' can be removed from the blood vessel 12 over the guide
wire 14 while the guide wire 14 is left in the blood vessel 12.
Thereafter, another vascular filtering device 1' can be introduced
in the blood vessel 12 over the guide wire 14.
[0038] According to the present invention, since the vascular
filtering device having a filter at a distal end portion thereof
can be placed in the downstream of the blood vessel while a PTCA
procedure is operated in an upstream of the blood vessel, even if
blood containing blood clots or debris due to PTCA procedure flows
to the downstream of the blood vessel, the blood clots or debris
can be captured and removed by the vascular filtering device
without blocking the blood flow. Thus, the debris or blood clots
can be prevented from migrating to the critical area, such as brain
and pulmonary arteries, during and after the PTCA procedure.
[0039] In the invention, since the balloon is firmly fixed to the
shaft and the filter at the inner and outer portions thereof, the
filter can be surely located in the blood vessel in use, and also,
the filter with the debris or blood clots can be made compact on
the shaft to be easily removed from the blood vessel.
[0040] While the invention has been explained with reference to the
specific embodiments of the invention, the explanation is
illustrative and the invention is limited only by the appended
claims.
* * * * *