U.S. patent application number 11/184644 was filed with the patent office on 2005-12-01 for disc shaped filter.
Invention is credited to Ungs, Mark T..
Application Number | 20050267517 11/184644 |
Document ID | / |
Family ID | 21931917 |
Filed Date | 2005-12-01 |
United States Patent
Application |
20050267517 |
Kind Code |
A1 |
Ungs, Mark T. |
December 1, 2005 |
Disc shaped filter
Abstract
Distal protection filter and method of using the same. A distal
protection filter may be coupled to an elongate shaft. The filter
includes a filter material coupled to a filter frame. The shape of
the filter may be generally cylindrical or disc shaped. The filter
material may capture embolic debris generated during an
intravascular intervention.
Inventors: |
Ungs, Mark T.; (Minnetonka,
MN) |
Correspondence
Address: |
CROMPTON, SEAGER & TUFTE, LLC
1221 NICOLLET AVENUE
SUITE 800
MINNEAPOLIS
MN
55403-2420
US
|
Family ID: |
21931917 |
Appl. No.: |
11/184644 |
Filed: |
July 19, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11184644 |
Jul 19, 2005 |
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10044354 |
Jan 10, 2002 |
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6932830 |
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Current U.S.
Class: |
606/200 |
Current CPC
Class: |
A61F 2/0108 20200501;
A61F 2230/0067 20130101; A61F 2002/018 20130101; A61F 2230/0006
20130101; A61F 2230/0078 20130101 |
Class at
Publication: |
606/200 |
International
Class: |
A61M 029/00 |
Claims
What is claimed is:
1. An intravascular filter apparatus, comprising: an elongate shaft
having a distal end; a generally cylindrical filter coupled to the
shaft near the distal end, the filter having a length and a
diameter; and wherein the diameter of the filter is larger than the
length.
Description
RELATED APPLICATIONS
[0001] This application is a continuation application of U.S.
application Ser. No. 10/044,354, filed Jan. 10, 2002.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention pertains to filtering devices. More
particularly, the present invention pertains to devices and methods
for filtering embolic debris from a blood vessel.
[0004] 2. Description of the Related Art
[0005] Occluded, stenotic, or narrowed blood vessels may be treated
with a number of relatively non-invasive medical procedures. For
example, occlusions of blood vessels near the heart may be treated
by percutaneous transluminal angioplasty (PTA), percutaneous
transluminal coronary angioplasty (PTCA), atherectomy, etc.
Similarly, a number of occlusions may occur in other blood vessels
located a distance away from the heart. For example, an occlusion
may occur within the renal artery between the abdominal aorta and
the kidney. Because this vascular region is relatively short in
length, an appropriate intervention may necessitate design
modifications of current intravascular devices.
[0006] When treating occluded or stenotic blood vessels, embolic
debris can be separated from the wall of the blood vessel. This
debris could block other vascular regions including the renal,
neural, and pulmonary vasculature or cause damage to tissue and/or
body organs. In order to filter this debris, a number of devices,
termed distal protection devices, have been developed.
BRIEF SUMMARY OF THE INVENTION
[0007] The present invention pertains to distal protection filter
devices. A distal protection filter may be coupled to an elongate
shaft. The filter may be generally cylindrical or disc shaped and
has a diameter and a length. The length is relatively small and may
be smaller than the diameter. The filter may be used to capture
embolic debris generated by an intravascular intervention.
Aspiration means may be included to aspirate the embolic debris
from the filter.
[0008] The filter may shift between a generally collapsed
configuration and a generally expanded configuration by a number of
methods. For example, an outer sheath may be disposed over the
shaft and filter such that movement of the sheath relative to the
shaft shifts the configuration of the filter. Alternatively, an
expansion member may be actuated to shift the filter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0009] FIG. 1 is a cross sectional view of a distal protection
filter;
[0010] FIG. 2 is a partial cross sectional view of depicting an
alternate means for shifting the filter between the expanded and
the collapsed configuration; and
[0011] FIG. 3 is a partial cross sectional view of the filter in
FIG. 2 in the expanded configuration.
DETAILED DESCRIPTION OF THE INVENTION
[0012] The following description should be read with reference to
the drawings wherein like reference numerals indicate like elements
throughout the several views. The detailed description and drawings
illustrate example embodiments of the claimed invention.
[0013] A number of diagnostic and therapeutic interventions may
result in the release of intravascular embolic debris. Several
filtering devices have been developed to capture and/or remove this
debris. However, some procedures and intravascular locations are
not readily accessible to traditional filters. FIG. 1 is a cross
sectional plan overview of a disc-shaped distal protection filter
device 10. Filter device 10 includes a filter 11 attached to an
elongate shaft 12. The design of filter device 10 permits filtering
at intravascular locations that might otherwise not be readily
accessible by traditional filters.
[0014] Shaft 12 may comprise a guidewire or intravascular catheter,
similar to any number of those known in the art or as detailed
below. A distal spring tip 16 may be disposed at a distal end 18 of
shaft 12. Sheath 14 may be generally polymeric and is adapted and
configured to be advanced through the vasculature to an area of
interest. Once positioned, sheath 14 may be withdrawn proximally to
deliver filter 11.
[0015] Filter 11 includes a filter material 20 coupled to a filter
frame 22. Filter material 20 may be comprised of a polyurethane
sheet and include at least one opening that may be, for example,
formed by known laser techniques. The holes or openings are sized
to allow blood flow therethrough but restrict flow of debris or
emboli floating in the body lumen or cavity.
[0016] Filter 11 operates between a closed collapsed profile and an
open radially-expanded deployed profile for collecting debris in a
body lumen. Frame 22 may be self-expanding or otherwise biased to
be oriented in the expanded configuration so that withdrawing
sheath 14 allows filter 11 to shift to the expanded configuration.
A number of methods may be used to shift filter 11 from the
expanded configuration to the collapsed configuration. For example,
filter 11 may include a plurality of longitudinally-extending
struts 24 that extend between frame 20 to shaft 12. It can be
appreciated that a number of methods for shifting filter 11 between
the collapsed and expanded configuration can be used without
departing from the spirit of the invention.
[0017] Filter 11 is designed to be disc shaped and/or cylindrical.
The cylindrical shape of filter 11 can be understood to have a
diameter D and a length L. Diameter D may generally be larger than
length L such that filter 11 has a shape that differs from typical
conically shaped filters. This characteristic of having a
relatively short or thin length may be described as having a "short
landing zone" to those in the art. Having a short landing zone can
advantageously permit filter 11 to be used at intravascular
locations that are relatively short and would otherwise be
inaccessible to traditional filters. For example, the length of a
portion of the renal artery between the abdominal aorta and the
kidney is relatively short. Diagnosis or other interventions at the
junction of the renal artery and the kidney would not easily be
accomplished by using conically shaped filter because the filter
may extend into the kidney, possibly causing damage to the kidney.
Because of the shape of filter 11, this location is accessible for
filtering by filter 11. A number of additional intravascular
locations may similarly benefit from the shape of filter 11.
[0018] The dimensions of filter 11 may include diameter D being
about 0.10 to 0.30 inches or less and length L may be about 0.01 to
0.15 inches or less. These dimensions are meant to be
approximations and provided for illustration purposes. The
dimensions may be altered for any one of multiple embodiments.
[0019] Shaft 12 may be generally tubular so as to define an
aspiration lumen 26 extending therethrough. Aspiration may be
important because the thin length of filter 11 may cause filter
material 20 to become filled to its capacity with embolic material.
Aspiration lumen 26 is connected proximally to a vacuum source and
is used to aspirate embolic debris collected on filter material
20.
[0020] In use, filter 11 may be contained within sheath 14 and
advanced within a blood vessel 28 to an area proximate a lesion 30.
Blood vessel 28 may, for example, be the renal artery between the
abdominal aorta and the kidney. Once positioned, sheath 14 may be
withdrawn from filter 11, permitting filter 11 to shift to the
expanded configuration. A therapeutic or diagnostic catheter may be
advanced to lesion 30 (i.e., over shaft 12 or sheath 14). Embolic
debris released by the intervention is captured by filter material
20. Aspiration lumen 26 may be used to aspirate the debris from
filter material 20.
[0021] FIG. 2 is a partial cross section of an alternate filter
device 110 that is the same in form and function as device 10
except that filter device 110 includes alternative means for
shifting filter 111 between the expanded and the collapsed
configuration. Filter 111 may be expanded by actuating a coiled
expansion member 132.
[0022] Expansion member 132 may include a generally straight
proximal portion 134 extending to the proximal end of shaft 12, and
a coiled distal portion 136. Distal portion 136 is coupled to
filter 111 such that force applied to proximal portion 136 in the
distal direction exerts force onto filter 111 in the distal
direction and shifts filter 111 distally. Distally shifting filter
111 results in filter 111 shifting to the expanded
configuration.
[0023] Proximal portion 134 may be connected to a manifold,
actuating handle, etc. that permits expansion member 132 to be
moved relative to shaft 12 by a clinician. According to this
embodiment, expansion member 132 is slidably disposed within shaft
12 and may be moved in either a proximal or distal direction. This
may permit the use of filter 111 without the need for a separate
delivery or retrieval catheter, which may simplify use and/or
overall profile of the device. Moreover, bi-directional motion of
expansion member 132 may alloy filter 111 to be positioned in one
location, expanded by distal motion of expansion member 132, filter
embolic debris, collapsed by proximal motion of expansion member
132, and moved to another location for use.
[0024] To expand filter 111, distal portion 136 is generally
tightly coiled within shaft 12 such that when it is allowed to
advance distally out of shaft 12, distal portion 136 expands to
expand filter 111 as shown in FIG. 3. It may be beneficial to
construct expansion member 132 (or at least distal portion 136) of
a shape-memory or superelastic alloy such as nickel-titanium alloy.
According to this embodiment, the size and/or shape of distal
portion 136 may be predetermined by heat setting distal portion 136
to the desired diameter and length. Multiple embodiments of the
invention incorporate alternate sizes and shapes of expansion
member 132. For example, expansion member 132 may be heat set to
expand so filter 111 has a larger diameter for one intervention and
a smaller diameter for another.
[0025] Expansion member 132 may be completely or partially
comprised of a radiopaque material. A radiopaque material is
understood to be capable of producing a relatively bright image on
a fluoroscopy screen or another imaging technique during a medical
procedure. This relatively bright image aids the user of filter 111
in determining its location. Radiopaque materials may include gold,
platinum, palladium, tantalum, tungsten alloy, and plastic material
loaded with a radiopaque filler. Filter 111 and/or shaft 12 may
further comprise additional radiopaque markers, similar to those
known in the art.
[0026] It should be understood that this disclosure is, in many
respects, only illustrative. Changes may be made in details,
particularly in matters of shape, size, and arrangement of steps
without exceeding the scope of the invention. The invention's scope
is, of course, defined in the language in which the appended claims
are expressed.
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