U.S. patent application number 09/912862 was filed with the patent office on 2003-01-30 for apparatus and methods for aspirating emboli.
This patent application is currently assigned to INCEPT LLC. Invention is credited to Krolik, Jeffrey, Salahieh, Amr.
Application Number | 20030023263 09/912862 |
Document ID | / |
Family ID | 25432575 |
Filed Date | 2003-01-30 |
United States Patent
Application |
20030023263 |
Kind Code |
A1 |
Krolik, Jeffrey ; et
al. |
January 30, 2003 |
Apparatus and methods for aspirating emboli
Abstract
Apparatus and methods for aspirating emboli from a vascular
filter or stent within a patient's circulatory system are provided.
A filter sac of the vascular filter permits blood flow and captures
emboli from the flow. The aspiration device removes emboli from
within or proximal to the vascular filter or stent to reduce the
risk to the ischemia during retrieval of the vascular filter and
during a treatment procedure. Retrieval of the vascular filter may
be accomplished using either the aspiration catheter or a separate
retrieval catheter.
Inventors: |
Krolik, Jeffrey; (Campbell,
CA) ; Salahieh, Amr; (Saratoga, CA) |
Correspondence
Address: |
Glenn M. Seager
CROMPTON, SEAGER & TUFTE, LLC
Suite 895
331 Second Avenue South
Minneapolis
MN
55401-2246
US
|
Assignee: |
INCEPT LLC
|
Family ID: |
25432575 |
Appl. No.: |
09/912862 |
Filed: |
July 24, 2001 |
Current U.S.
Class: |
606/200 |
Current CPC
Class: |
A61F 2/0105 20200501;
A61B 2217/005 20130101; A61B 17/221 20130101; A61B 17/22 20130101;
A61F 2/01 20130101 |
Class at
Publication: |
606/200 |
International
Class: |
A61M 029/00 |
Claims
What is claimed is:
1. Apparatus for filtering and aspirating emboli from a vessel
comprising: a vascular filter having a blood-permeable element
disposed on a guidewire, the vascular filter causing emboli to
become deposited in the vessel in the vicinity of the vascular
filter; a first catheter having proximal and distal ends, proximal
and distal openings, and a lumen extending between the proximal and
distal openings, wherein the first catheter is adapted to be
advanced along the guidewire to a location in the vessel in the
vicinity of the vascular filter to aspirate emboli.
2. The apparatus of claim 1 wherein the distal end of the first
catheter is dimensioned so that the distal opening enters the
blood-permeable element.
3. The apparatus of claim 1 wherein the distal opening of the first
catheter is dimensioned so that the vascular filter may be at least
partially retracted in the lumen of the first catheter.
4. The apparatus of claim 1 wherein the distal end of the first
catheter is curved.
5. The apparatus of claim 1 wherein the distal end of the first
catheter includes one or more aspiration holes disposed proximal of
the distal opening.
6. The apparatus of claim 1 wherein the first catheter comprises a
rapid exchange device.
7. The apparatus of claim 1 wherein the first catheter comprises an
over-the-wire device.
8. The apparatus of claim 1 further comprising a second catheter
having proximal and distal ends, proximal and distal openings, and
a lumen extending between the proximal and distal openings, the
lumen of the second catheter dimensioned to accept the first
catheter therein.
9. The apparatus of claim 8 wherein the first catheter includes one
or more aspiration holes disposed proximal of the distal opening
and the second catheter selectively occludes the one or more
aspiration holes.
10. The apparatus of claim 8 wherein the distal opening of the
second catheter is dimensioned so that the vascular filter may be
at least partially retracted in the lumen of the second
catheter.
11. A method of aspirating emboli from a vessel comprising:
delivering a vascular filter having a blood-permeable element to a
treatment site within a vessel so that emboli become deposited in
the vessel in the vicinity of the vascular filter; providing a
first catheter having proximal and distal ends, proximal and distal
openings, and a lumen extending between the proximal and distal
openings; advancing the first catheter to a location in the vessel
so that the distal opening is in close proximity to the vascular
filter; and inducing suction at the proximal opening to aspirate
emboli from the vessel through the distal opening into the lumen of
the first catheter.
12. The method of claim 11 further comprising, while inducing
suction, moving the first catheter slightly proximally and distally
relative to the vascular filter.
13. The method of claim 11 further comprising, while inducing
suction, advancing the distal end and distal opening of the first
catheter within the vascular filter.
14. The method of claim 11 further comprising advancing the first
catheter to retrieve at least a portion of the vascular filter
through the distal opening and into the lumen of the first
catheter.
15. The method of claim 11 further comprising: providing a second
catheter having proximal and distal ends, proximal and distal
openings, and a lumen extending between the proximal and distal
openings; and advancing the second catheter over the first catheter
to retrieve at least a portion of the vascular filter through the
distal opening and into the lumen of the second catheter.
16. A method of aspirating emboli from a vessel in the vicinity of
a stent, comprising: delivering a vascular filter having a
blood-permeable element to a treatment site within a vessel so that
emboli become deposited in the vessel in the vicinity of the
vascular filter; delivering a stent into the vessel at a location
proximal of the vascular filter; providing a first catheter having
proximal and distal ends, proximal and distal openings, and a lumen
extending between the proximal and distal openings; advancing the
first catheter to a location in the vessel so that the distal
opening is in close proximity to the stent; and inducing suction at
the proximal opening to aspirate emboli from the vessel through the
distal opening into the lumen of the first catheter.
17. The method of claim 16 further comprising, while inducing
suction, moving the first catheter slightly proximally and distally
relative to the stent.
18. The method of claim 16 further comprising, while inducing
suction, advancing the distal end and distal opening of the first
catheter within the stent.
19. The method of claim 16 further comprising advancing the first
catheter to retrieve at least a portion of the vascular filter
through the distal opening and into the lumen of the first
catheter.
20. The method of claim 16 further comprising: providing a second
catheter having proximal and distal ends, proximal and distal
openings, and a lumen extending between the proximal and distal
openings; and advancing the second catheter over the first catheter
to retrieve at least a portion of the vascular filter through the
distal opening and into the lumen of the second catheter.
21. An intravascular aspiration system, comprising: a first
catheter having proximal and distal ends, proximal and distal
openings, and a lumen extending between the proximal and distal
openings; a guidewire; and wherein the first catheter is adapted to
be advanced along the guidewire to a location in a blood vessel to
aspirate emboli.
22. The system of claim 21, further comprising a vascular filter
disposed on the guidewire, the vascular filter including a
blood-permeable element.
23. The system of claim 22, wherein a nose cone is coupled to the
blood-permeable element.
24. The system of claim 21 wherein the distal end of the first
catheter includes one or more aspiration holes disposed proximal of
the distal opening.
25. The system of claim 21 further comprising a second catheter
having proximal and distal ends, proximal and distal openings, and
a lumen extending between the proximal and distal openings, the
lumen of the second catheter dimensioned to accept the first
catheter therein.
26. The system of claim 25 wherein the first catheter includes one
or more aspiration holes disposed proximal of the distal opening
and the second catheter selectively occludes the one or more
aspiration holes.
27. The system of claim 21, further comprising a syringe coupled to
a side port of the first catheter.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to apparatus and methods for
aspirating emboli. More particularly, the present invention
provides apparatus useful for aspirating emboli from a vascular
device such as a vascular filter used to prevent embolization
associated with diagnostic or therapeutic interventional
procedures, thrombectomy and embolectomy.
BACKGROUND OF THE INVENTION
[0002] Percutaneous interventional procedures to treat occlusive
vascular disease, such as angioplasty, atherectomy, and stenting,
often dislodge material from the vessel walls. This dislodged
material, known as emboli, enters the bloodstream and may be large
enough to occlude smaller downstream vessels, potentially blocking
blood flow to tissue. The resulting ischemia poses a serious threat
to the health or life of a patient if the blockage occurs in
critical tissue, such as the heart, lungs, or brain.
[0003] The deployment of stents and stent-grafts to treat vascular
disease, such as aneurysms, involves the introduction of foreign
objects into the bloodstream, and also may result in the formation
of clots or release of emboli. Such particulate matter, if released
into the bloodstream, also may cause infarction or stroke.
[0004] Numerous blood filters have been designed to capture
material liberated from vessel walls during the treatment of
vascular disease. Such treatment procedures, such as angioplasty,
typically involve transluminally inserting an interventional
device, such as an angioplasty catheter, to the treatment site
along a guidewire. During a typical interventional angioplasty
treatment procedure, the balloon of the angioplasty catheter is
inflated within the vessel at least once but often more than once.
First a pre-dilatation angioplasty catheter is inflated against the
vessel to pre-dilate it. Next a stent delivery angioplasty catheter
is inflated to deploy the stent. Finally a post-dilation
angioplasty catheter is inflated to properly seat the stent against
the vessel. Each of the inflations and manipulations of the
interventional devices often liberate emboli from the vessel walls.
The emboli enters the bloodstream and flows into a vascular filter,
where it remains for the duration of the treatment procedure.
[0005] Is has been postulated that a vascular filter may become
occluded with emboli during a transluminal diagnostic or
therapeutic procedure, thus occluding flow of blood through the
filter. Additional emboli, generated proximal to the vascular
filter by the angioplasty catheter, may then be unable to flow
downstream and into the vascular filter. When the vascular filter
is collapsed for retrieval, the restored flow of blood through the
vessel may carry those additional emboli downstream past the
collapsed filter, potentially jeopardizing the patient's
health.
[0006] An additional disadvantage postulated to occur when
retrieving an emboli-ladened vascular filter is that the vascular
filter may become entangled with a stent disposed within the
patient's vessel. If, for example, a stent has been deployed, the
vascular filter may inadvertently engage a stent strut, preventing
further advancement of the vascular filter within the vessel, or
even possibly causing vessel dissection.
[0007] Also, emboli may temporarily adhere to stents disposed
within a patient's vessel. When blood flow is subsequently
restored, the emboli may re-enter the bloodstream and cause
infarction or stroke.
[0008] In view of the foregoing, it would be desirable to provide
improved apparatus and methods for aspirating emboli from a blood
vessel in which a vascular filter is used in conjunction with a
transluminal diagnostic or therapeutic procedure and/or in which a
stent is deployed.
SUMMARY OF THE INVENTION
[0009] The present invention pertains to apparatus and methods for
aspirating emboli from a blood vessel in which a vascular filter is
used in conjunction with a transluminal diagnostic or therapeutic
procedure and/or in which a stent is deployed. The risk associated
with retrieving a vascular filter from a patient's vessel can be
decreased by using an aspiration device that aspirates emboli from
a blood vessel in which a vascular filter and/or a stent is
placed.
[0010] The aspiration recovery devices of the present invention are
intended to remove emboli immediately adjacent to or contained
within a filter sac of a vascular filter. Additionally, the
aspiration device may be used to retrieve the vascular filter. Two
families of aspiration recovery devices are provided: a single
catheter type and telescoping dual catheter type. The single
catheter type device uses one catheter both to aspirate emboli and
retrieve a vascular filter. The telescoping dual catheter type
device uses two catheters, with one catheter disposed inside the
other, so that the inner catheter is used to aspirate emboli from a
vascular filter and the outer catheter is used to retrieve the
vascular filter.
[0011] Both the single catheter and the telescoping dual catheter
types of aspiration recovery devices may be over-the-wire devices
or rapid exchange devices. Aspiration through the catheters may be
accomplished using a syringe coupled to the catheter via a
hemostatic valve, wherein retracting the plunger of the syringe
aspirates and amount of blood from the patient in a range of about
10 ml to 50 ml. Alternatively, a vacuum hook-up, such as a standard
suction port available in a hospital operating room, may be
used.
[0012] Both rapid exchange and over-the-wire aspiration recovery
devices of the present invention may be used to aspirate emboli
from within or proximal to a vascular filter liberated from a
patient's vessel wall by an interventional device. Devices
constructed in accordance with the present invention also may be
used to aspirate emboli from the filter sac of a vascular filter
during a procedure. Additionally, the present invention may be used
to aspirate emboli from around a stent placed in a patient's
vessel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a perspective view of a first previously known
vascular filter suitable for use with the apparatus of the present
invention;
[0014] FIG. 2 is a perspective view of another previously known
vascular filter suitable for use with the apparatus of the present
invention;
[0015] FIG. 3 is a side view of yet another vascular filter
suitable for use with the apparatus of the present invention;
[0016] FIG. 4A is a perspective view of an over-the-wire single
catheter aspiration recovery device of the present invention;
[0017] FIG. 4B is a perspective view of a rapid exchange single
catheter aspiration recovery device of the present invention;
[0018] FIG. 5A is a side sectional view of the distal end of a
rapid exchange single catheter aspiration recovery device of the
present invention;
[0019] FIGS. 5B-5C are cross sectional views of the aspiration
recovery device of FIG. 5A;
[0020] FIG. 5D is a side sectional view of the aspiration recovery
device of FIG. 5A and a collapsed vascular filter;
[0021] FIG. 6 is a perspective view of the distal end of another
embodiment of the rapid exchange single catheter aspiration
recovery device of the present invention;
[0022] FIG. 7 is a side sectional view of the distal end of an
over-the-wire single catheter aspiration recovery device of the
present invention;
[0023] FIGS. 8A-8B are perspective views depicting a method of
aspirating emboli and recovering a vascular filter using the
aspiration recovery device of FIG. 7;
[0024] FIG. 9 is a side sectional view of the distal end of another
embodiment of the over-the-wire single catheter aspiration recovery
device of the present invention;
[0025] FIGS. 10A-10D are perspective views depicting a method of
aspirating emboli and recovering a vascular filter using a rapid
exchange telescoping catheter aspiration recovery device of the
present invention;
[0026] FIG. 10E is a perspective view of the distal end of the
aspiration recovery device of FIGS. 10A-10D;
[0027] FIG. 10F is a cross sectional view of the aspiration
recovery device of FIGS. 10A-10D;
[0028] FIGS. 11A-11B are perspective views of the distal end of
another embodiment of the rapid exchange telescoping catheter
aspiration recovery device of the present invention;
[0029] FIG. 11C is a cross sectional view of the aspiration
recovery device of FIGS. 11A-11B;
[0030] FIG. 12 is a perspective view of the distal end of yet
another embodiment of the rapid exchange telescoping catheter
aspiration recovery device of the present invention;
[0031] FIGS. 13A-13C are perspective views depicting a method of
aspirating emobli and recovering a vascular filter using the
aspiration recovery device of FIG. 12;
[0032] FIG. 14 is a frontal view of the aspiration recovery device
of FIG. 12;
[0033] FIG. 15 is a perspective view of the distal end of an
over-the-wire telescoping catheter aspiration recovery device of
the present invention; and
[0034] FIGS. 16A-16C are perspective views depicting a method of
aspirating emboli and recovering a vascular filter using the
aspiration recovery device of FIG. 15.
DETAILED DESCRIPTION OF THE INVENTION
[0035] The present invention is directed to apparatus and methods
for aspirating emboli from a blood vessel in which a vascular
filter and/or a stent is used and decreasing the risk associated
with retrieving a vascular filter from a patient's vessel.
[0036] A number of vascular filters are known for providing distal
protection against embolization in conjunction with a transluminal
diagnostic or therapeutic procedure, such as angioplasty. These
filters generally are deployed distal to a vascular lesion prior to
undertaking a diagnostic or therapeutic procedure, and are designed
to filter emboli liberated during the procedure from the patient's
blood. A brief description of a number of these filters is provided
as context for advantages achievable using the apparatus of the
present invention.
[0037] FIG. 1 shows vascular filter 10 described in U.S. Pat. No.
6,129,739 to Khosravi et al., which is incorporated herein in its
entirety. Vascular filter 10 includes articulated support hoop 11
carrying blood-permeable element 12. Support hoop 11 is attached to
tube 13 at point 14, and permits guidewire 15 to be rotated
independently of support hoop 11. Blood-permeable element 12
filters emboli and other undesirable material from blood passing
through the filter, while permitting blood cells to pass freely
therethrough. When an interventional procedure, e.g., angioplasty
or stenting, is completed, vascular filter 10 is retrieved by
partially withdrawing support hoop 11 into the lumen of the
interventional device (e.g., angioplasty catheter), and removing
the catheter and vascular filter.
[0038] FIG. 2 depicts another type of vascular filter suitable for
use with the methods and apparatus of the present invention, and is
described in U.S. Pat. No. 6,152,946 to Broome et al., which is
incorporated herein by reference. Vascular filter 20 includes a
plurality of longitudinally-extending ribs 21 forming frame 22 that
supports mouth 23. Cone-shaped filter 24 is coupled to mouth 23.
Ribs 21 are coupled to collar 25, which is displaced distally along
guidewire 26 to expand and deploy frame 22 and filter 24. Filter 24
includes holes 27 that permit blood to pass through the filter,
while trapping emboli. Vascular filter 20 is collapsed for
retrieval by applying a load against ribs 21 that causes collar 25
to slide proximally, thereby closing the vascular filter.
[0039] Referring now to FIG. 3, another vascular filter suitable
for use with the apparatus and methods of the present invention is
described. Vascular filter 30 is described in detail in co-pending,
commonly assigned U.S. patent application Ser. No. 09/764,774,
filed Jan. 16, 2000, and is summarily described here.
[0040] Vascular filter 30 preferably includes self-expanding
support hoop 31 mounted on suspension strut 32, and supports
blood-permeable element 33. Blood-permeable element 33 comprises a
biocompatible polymeric material having a multiplicity of pores.
Suspension strut 32 is affixed at proximal end 34 to tube 35, and
positions support hoop 31 approximately concentric to tube 35 when
disposed in a substantially straight length of vessel, but
advantageously permits the support hoop to become eccentrically
displaced relative to support tube 35 when the filter is deployed
in a curved vessel.
[0041] Distal end 36 of blood-permeable element 33 is
illustratively mounted to nose cone 37, which is in turn mounted to
tube 35. Filter 30 is mounted on guidewire 38 between proximal stop
39 and enlarged floppy tip 40 of the guidewire, which functions as
a distal stop. Tube 35 permits guidewire 38 to rotate independently
of filter 30, thereby permitting floppy tip 40 of the guidewire to
be directed within the vessel without causing blood-permeable
element 33 to become wrapped around guidewire 38.
[0042] The aspiration recovery devices of the present invention are
intended to remove emboli proximal to or within a filter sac of a
vascular filter, such as those described above in the context of
FIGS. 1-3. Additionally, the recovery devices may be used to
retrieve the vascular filter. Two families of aspiration recovery
devices are provided: a single catheter type and a telescoping dual
catheter type. The single catheter type device uses one catheter
both to aspirate emboli and retrieve a vascular filter. The
telescoping dual catheter type device uses two catheters, with one
catheter disposed inside the other, so that the inner catheter is
used to aspirate emboli from a vascular filter and the outer
catheter is used to retrieve the vascular filter.
[0043] Both the single catheter and the telescoping dual catheter
types of aspiration recovery devices may be over-the-wire devices
or rapid exchange devices. As is well known, in an over-the-wire
device, the guidewire is disposed within the entire length of the
catheter, whereas in a rapid exchange device the guidewire is
disposed only within a short portion at the distal end of the
catheter.
[0044] Referring now to FIG. 4A, an embodiment of an over-the-wire
single catheter aspiration recovery device constructed in
accordance with the principles of the present invention is
described. Aspiration recovery device 50 illustratively includes
syringe 53 with plunger 54 and chamber 55. Syringe 53 is coupled to
side port 56 of catheter 52. Catheter 52 also includes hemostatic
valve 57. Catheter 52 may be used for both aspiration of emboli and
retrieval of a vascular filter, for example, vascular filter 30 of
FIG. 3.
[0045] Syringe 53 may be any existing syringe capable of inducing
low pressure in chamber 55 when plunger 54 is retracted, thereby
creating a pressure gradient between distal end 51 in the patient's
vasculature and chamber 55. This pressure gradient causes fluid and
material, specifically blood and emboli, to be aspirated from a
region within or proximal to vascular filter 30 to chamber 55 via
catheter 52. The amount of blood removed from the patient using
syringe 53 preferably is in a range of about 10 ml to 50 ml. The
amount of blood aspirated to chamber 55 at the completion of a
treatment procedure is generally sufficiently small that no effort
need by made to cleanse and reintroduce the blood to the patient's
circulatory system. Alternatively, the blood removed from the body
may be filtered and reintroduced to the patient, if desired.
[0046] While FIG. 4A depicts an over-the-wire single catheter
device, syringe 53 also may be used in conjunction with an
over-the-wire telescoping dual catheter device, described
hereinafter. In addition, while the present invention is
illustrated with a syringe as the aspiration inducer, it should be
understood that any other suitable device that induces suction may
be used, such as a standard suction port available in a hospital
operating room.
[0047] With respect to FIG. 4B, a rapid exchange embodiment of a
single catheter aspiration recovery device is described. Aspiration
recovery device 60 includes syringe 65 with plunger 66 and chamber
64 coupled at connection 63 to aspiration catheter 62. Catheter 62
may be used for both aspiration of emboli and retrieval of a
vascular filter, such as those described above in FIGS. 1-3.
[0048] Syringe 65 preferably is constructed as described above with
respect to syringe 53 of FIG. 4A, and is actuated by retracting
plunger 66 proximally. When so retracted, fluid and emboli within
or proximal to vascular filter 30 are drawn into distal end 61,
through catheter 62, and into chamber 64, as described above for
the embodiment of FIG. 4A.
[0049] Both the rapid exchange and the over-the-wire aspiration
recovery devices of the present invention may be used to aspirate
emboli liberated from a patient's vessel wall by an interventional
device, such as an angioplasty catheter, an atherectomy catheter,
an embolectomy catheter, a vascular mapping catheter, stent
delivery device or other diagnostic or therapeutic interventional
device, from within or proximal to a vascular filter.
[0050] Referring now to FIG. 5A, a rapid exchange single catheter
aspiration recovery device 70 is described. Catheter 74 preferably
is constructed of a thin biocompatible material, as described
hereinabove, and has sufficient stiffness to permit the catheter to
be pushed along a guide wire through curved vasculature within a
patient's circulatory system, and will not collapse when the
syringe is actuated. The distal end of catheter 74 may include a
radiopaque marker or may be entirely radiopaque. Radiopaque 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 in
determining the location of the distal end catheter 74. Radiopaque
materials may include, but are not limited to, gold, platinum,
tungsten alloy, and plastic material loaded with a radiopaque
filler.
[0051] Catheter 74 optionally may include bent tip 72, which has a
rounded profile to risk the risk of injury to a patient's vessel,
or inadvertently becoming entangled with a stent, as it is advanced
toward a treatment area. Opening 71 of tip 72 (see FIG. 5D)
provides a rounded profile that enhances trackability. Guidewire 78
enters guidewire lumen 77 proximally through skive 76 and exits
catheter 74 through distal opening 71, as illustrated in FIGS. 5B
and 5C.
[0052] In accordance with the principles of the present invention,
catheter 74 is used to aspirate emboli from a location proximal to
a vascular filter, using syringe 65 or other suitable suction
source. Emboli are aspirated through opening 71 to chamber 64 of
syringe 65. Additionally, catheter 74 may be moved slightly in the
proximal and distal directions relative to vascular filter 30 to
vacuum up emboli disposed proximal to vascular filter 30. Once the
aspiration step is completed, catheter 74 then may be advanced
toward vascular filter 30 to collapse and retrieve the vascular
filter through opening 71. Alternatively, upon completion of the
interventional procedure, guidewire 78 and attached vascular filter
30 may be withdrawn proximally until the vascular filter engages
and is caused to be collapsed within catheter 74.
[0053] With respect to FIG. 6, the distal end of an alternative
embodiment of a rapid exchange single catheter aspiration recovery
device of the present invention is described. Device 80 is
substantially similar to device 70 of FIGS. 5, except that device
80 includes an additional aspiration hole 83 to facilitate
aspiration of emboli proximal to a vascular filter. Device 70 may
also include a radiopaque marker similar to that described
above.
[0054] Referring to FIGS. 7 and 8, the distal end of an
over-the-wire single catheter aspiration recovery device 90 is now
described. Preferably, catheter 94 is constructed as described
hereinabove, and may include a radiopaque marker or may be entirely
radiopaque to permit the viewing of the catheter using a
fluoroscope. Catheter 94 includes tapered tip 92, wherein the
leading edges are rounded to reduce the risk of vessel injury or
stent entanglement.
[0055] Catheter 94 may be used to aspirate emboli from a location
proximal to vascular filter 30 using syringe 53 as described above
with respect to FIG. 4A. Emboli E that are both proximal to and
within vascular filter 30 may travel proximally and enter
aspiration holes 93 of catheter 94 when suction is induced through
the catheter, for example, by actuating syringe 53 (see FIG. 4A).
After the aspiration step is completed, catheter 94 may be advanced
distally toward vascular filter 30 to collapse and retrieve the
vascular filter in opening 95, or alternatively, guidewire 91 and
attached vascular filter 30 may be withdrawn proximally to retrieve
the vascular filter into opening 95 of catheter 94.
[0056] With respect to FIG. 9, device 100 is substantially similar
to device 90 of FIGS. 7 and 8, except that device 100 includes bump
tip 102 with opening 101 to facilitate aspiration of emboli from a
location proximal to a vascular filter and to collapse the vascular
filter. Tip 102 is rounded to reduce the risk of vessel injury or
stent entanglement.
[0057] With reference to FIGS. 10A-10D, a rapid exchange
telescoping catheter aspiration recovery device 110 is described.
Device 110 includes aspiration catheter 112 disposed within a lumen
of retrieval catheter 113. Preferably, aspiration catheter 112 and
retrieval catheter 113 are constructed as described hereinabove for
previous catheter embodiments and may include a radiopaque
marker.
[0058] Distal end 114 of aspiration catheter 112 is configured to
reduce the risk of becoming entangled with a stent disposed within
a patient's vessel. Distal end 114 includes rounded edge 117
disposed at angle 116 to facilitate movement through the vessel,
and to improve maneuverability of catheter 112 by creating a
leading edge to track through the vessel. Angle 116 preferably is
less than 90-degrees, resulting in oblique opening 115 of distal
end 114.
[0059] In FIGS. 10A-10D, a method for aspirating emboli and
retrieving a vascular filter is illustrated. FIG. 10A illustrates a
step of a treatment procedure, wherein vascular filter 30 is
disposed at a distal end of guidewire 111 followed by aspiration
catheter 112 and retrieval catheter 113. FIG. 10F depicts guidewire
111 disposed within a guide wire lumen of retrieval catheter 113,
and externally to aspiration catheter 112. At the conclusion of an
interventional procedure, the interventional device is removed and
aspiration recovery catheter 110 then is advanced along guidewire
111 to a position just proximal of vascular filter 30.
[0060] As depicted in FIG. 10B, aspiration catheter 112 is advanced
distally through mouth 41 and into blood-permeable element 33 of
vascular filter 30. Suction is then applied to the proximal end of
catheter 112 to aspirate emboli E from within blood-permeable
element 33 into opening 115, and through aspiration catheter 112.
Aspiration catheter 112 also may be moved in small distances back
and forth within blood-permeable element 33 to permit distal end
114 to unburden vascular filter 30.
[0061] As shown in FIG. 10C, aspiration catheter 112 then is
retracted proximally into retrieval catheter 113. In FIG. 10D,
retrieval catheter 113 then is advanced distally to encapsulate
vascular filter 30. Catheters 112 and 113, guidewire 111 and
vascular filter 30 may then be removed from the patient's
vasculature. Alternatively, guidewire 111 and attached vascular
filter 30 may be withdrawn proximally into retrieval catheter
113.
[0062] With respect to FIGS. 11A-11C, another embodiment of the
rapid exchange telescoping catheter aspiration recovery device of
the present invention is described. Device 120 is substantially
similar to device 110 of FIGS. 10, except that device 120 also
includes nose cone 122, one or more aspiration holes 126,
aspiration hole 125, and inner catheter 123 is keyed to outer
catheter 124 (see FIG. 11C).
[0063] Nose cone 122 facilitates tracking through a patient's
vessel, and preferably includes rounded tip 121, which reduces the
risk of vessel injury or stent entanglement. Advancing aspiration
catheter 123 from within retrieval catheter 124 toward a vascular
filter, such as vascular filter 30, exposes aspiration holes 125
and 126, as shown in FIG. 1B, which as otherwise covered by
retrieval catheter 124 as device 120 travels toward vascular filter
30. This arrangement reduces the risk that aspiration holes 125 and
126 will become entangled with a stent strut as device 120 is
advanced toward a treatment site along guidewire 111.
[0064] As shown in FIG. 11C, catheter 123 is keyed within catheter
124 to maintain relative alignment of the catheters. This ensures
that the aspiration catheter is at a proper orientation when
entering a vascular filter, such as vascular filter 30.
[0065] FIGS. 12-14 show yet another embodiment of the rapid
exchange telescoping catheter aspiration recovery device of the
present invention. Device 130 is substantially similar to device
120 of FIGS. 11, except that device 130 includes distal end 132
with aspiration holes 133 and 134, rather than a nose cone and
aspiration holes that are hidden by a retrieval catheter.
[0066] In FIGS. 13A, vascular filter 30 is disposed at a distal end
of guidewire 111 followed by aspiration catheter 135 and retrieval
catheter 131. This arrangement may be used to aspirate emboli E
from vascular filter 30 following a treatment procedure such as
angioplasty involving an interventional device such as an
angioplasty catheter (not shown) and vascular filter 30.
[0067] In FIG. 13B, aspiration catheter 135 is moved distally
through mouth 41 and into blood-permeable element 33 of vascular
filter 30, and suction is drawn on the proximal end of aspiration
catheter 133 to aspirate emboli E from within blood-permeable
element 33. In FIG. 13C, aspiration catheter 135 then is retracted
proximally to exit vascular filter 30, and retrieval catheter 131
is advanced distally to retrieve vascular filter 30. Alternatively,
guidewire 111 and attached vascular filter 30 may be withdrawn
proximally until the vascular filter is retrieved within catheter
131.
[0068] FIGS. 15-16C show over-the-wire telescoping catheter
aspiration recovery device 140. Device 140 includes aspiration
catheter 145 with aspiration holes 143 and slit 144 and retrieval
catheter 146. Preferably, aspiration catheter 145 and retrieval
catheter 146 are constructed as described hereinabove, and are used
in a method similar to that of catheters 112 and 113 of FIGS.
10.
[0069] The present invention describes a method of aspirating
emboli from a filter sac of a vascular filter prior to retrieval.
However, a similar method may be used to aspirate emboli from the
filter sac of the vascular filter during a procedure (not shown),
for example, in the event that the sac of the vascular filter fills
to capacity during a treatment procedure. Additionally, the present
invention may be used to aspirate emboli from around a stent which
may be in place within a patient's vessel.
[0070] Although preferred illustrative embodiments of the present
invention are described above, it will be evident to one skilled in
the art that various changes and modifications may be made without
departing from the invention. It is intended in the appended claims
to cover all such changes and modifications that fall within the
true spirit and scope of the invention.
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