U.S. patent application number 15/406568 was filed with the patent office on 2017-05-04 for method for delivery of an embolic protection unit.
This patent application is currently assigned to SWAT Medical AB. The applicant listed for this patent is SWAT Medical AB. Invention is credited to Erik Krahbichler.
Application Number | 20170119518 15/406568 |
Document ID | / |
Family ID | 50975529 |
Filed Date | 2017-05-04 |
United States Patent
Application |
20170119518 |
Kind Code |
A1 |
Krahbichler; Erik |
May 4, 2017 |
Method For Delivery Of An Embolic Protection Unit
Abstract
A method of delivering a embolic protection unit to the aorta
arch of a patient. The method comprising, introducing a catheter
from brachiocephalic artery or through an incision in a wall of the
ascending aorta, the catheter comprising an embolic protection unit
having an off-center connection point. Advancing the embolic
protection unit in a downstream direction from the catheter.
Expanding the embolic protection unit in the aorta arch to cover
said ostia. Delivering a medical device into the ascending aorta
while the embolic protection unit is hold by the catheter covering
the ostia.
Inventors: |
Krahbichler; Erik;
(Helsingborg, SE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SWAT Medical AB |
Helsinborg |
|
SE |
|
|
Assignee: |
SWAT Medical AB
Helsingborg
SE
|
Family ID: |
50975529 |
Appl. No.: |
15/406568 |
Filed: |
January 13, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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14080703 |
Nov 14, 2013 |
9579182 |
|
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15406568 |
|
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61726540 |
Nov 14, 2012 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 2/011 20200501;
A61F 2230/0093 20130101; A61F 2/013 20130101; A61F 2002/016
20130101; A61F 2/24 20130101; A61M 2025/0063 20130101 |
International
Class: |
A61F 2/01 20060101
A61F002/01 |
Claims
1. A method of delivering an embolic protection unit to the aorta
arch of a patient comprising: introducing a catheter through an
incision in a wall of an ascending aorta of a patient, said
catheter comprising an embolic protection unit having an off-center
connection point; advancing said embolic protection unit in a
downstream direction from said catheter; expanding said embolic
protection unit in an aorta arch to cover an ostia of the patient;
delivering a medical device into the ascending aorta while said
embolic protection unit is held by said catheter covering said
ostia; and making an incision in a wall of the ascending aorta
upstream of said introduced catheter for introducing said medical
device while said embolic protection unit is protecting said
ostia.
2. The method according to claim 1, wherein said embolic protection
unit is expanded to a non-tubular, substantially planar shape over
said ostia.
3. The method according to claim 1, wherein said catheter is
introduced towards a cardiac valve coaxially in said ascending
aorta, or wherein said medical device is introduced towards said
cardiac valve coaxially in said ascending aorta.
4. The method according to claim 1, wherein said catheter comprises
an elongated sheath with a first channel and a second channel from
which said embolic protection unit is expanded, said second channel
is arranged within said first channel or said catheter comprises an
elongated sheath with a first channel and a second channel is
arranged around said elongated sheath.
5. The method according to claim 4, comprising introducing a
pigtail through one of said channels.
6. The method according to claim 4, wherein said second channel is
arranged helically around said elongated sheath, and wherein said
second channel has an opening directed at an angle away from an
opening of said first channel in a direction toward the aorta arch
when said opening of said first channel is directed towards the
ascending aorta.
7. The method according to claim 4, further comprising, radially
expanding expandable units of said catheter or an elongated member
positioned beyond a distal end of said elongated sheath, to
temporarily position in relation to said valve said elongated
sheath; releasing locking members of said catheter to maintain said
elongated sheath in a locked state; delivering a medical device
through said first channel to said cardiac valve; releasing said
locking members to return said elongated sheath to a relaxed state;
and withdrawing said elongated sheath in said relaxed state from
the vasculature of said patient.
8. The method according to claim 7 further comprising, inserting an
elongated member with a distal end portion comprising a plurality
of said radially expandable units into said first channel of said
elongated sheath; advancing said elongated member through said
elongated sheath to said distal end of said elongated sheath;
retracting said expandable units and withdrawing said elongated
member from said first channel of the elongated sheath.
9. The method according to claim 17, wherein said supported
apposition is improving apposition of said periphery to said inner
wall of said aortic arch, such that said improved apposition
provides for improved sealing of said periphery against said inner
wall.
10. The method according to claim 9, wherein said force is applied
in a substantially proximal direction relative said device for said
improved sealing.
11. The method according to claim 17, wherein applying said force
includes applying a tractive force by a traction unit or a pushing
force by a pushing unit.
12. The method according to claim 1, wherein said medical device is
a bypass machine.
13. The method according to claim 1, wherein said medical device is
for a TAVI procedure where a stent valve is delivered while said
embolic protection unit is positioned and with said catheter in
said aorta arch.
14. The method according to claim 1, wherein said medical device is
a device for electrophysiology.
15. The method according to claim 1, wherein advancing said embolic
protection unit in a downstream direction from said catheter
comprises, advancing a second catheter through a channel of said
catheter, said second catheter has a retractable sheath enclosing
said embolic protection unit; retracting said sheath whereby said
embolic protection unit expands.
16. The method according to claim 15, wherein said second catheter
has a distal end having a bend.
17. A method of delivering an embolic protection unit to an aorta
arch of a patient comprising: introducing a catheter from a
brachiocephalic artery or through an incision in a wall of an
ascending aorta of the patient, said catheter comprising an embolic
protection unit having an off-center connection point; advancing
said embolic protection unit in a downstream direction from said
catheter; expanding said embolic protection unit in the aorta arch
to cover an ostia of the patient; delivering a medical device into
the ascending aorta while said embolic protection unit is held by
said catheter covering said ostia; and introducing said catheter in
a direction towards said aorta arch; retracting said catheter after
expanding said embolic protection unit in said aorta arch;
forwarding said catheter towards a cardiac valve coaxially in said
ascending aorta; and using at least one tissue apposition
sustaining unit, not being a delivery shaft of said embolic
protection unit, for application of a force offset to said
connection point at said embolic protection unit towards an inner
wall of said aortic arch when said embolic protection unit is
positioned in said aortic arch such that tissue apposition of a
periphery to an inner wall of said aortic arch is supported by said
force.
18. A method of delivering an embolic protection unit to an aorta
arch of a patient comprising: introducing a catheter from a
brachiocephalic artery or through an incision in a wall of an
ascending aorta of the patient, said catheter comprising an embolic
protection unit having an off-center connection point; advancing
said embolic protection unit in a downstream direction from said
catheter; expanding said embolic protection unit in the aorta arch
to cover an ostia of the patient; and delivering a medical device
into the ascending aorta while said embolic protection unit is held
by said catheter covering said ostia; wherein said introducing said
catheter includes placing a balloon mounted on said catheter and
expanding said balloon in the ascending aorta; and wherein said
balloon is a donut shaped balloon having a filter between said
catheter and an inner ring of said donut shape.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of and claims priority to
U.S. patent application Ser. No. 14/080,703 filed Nov. 14, 2013
entitled Method For Delivery Of An Embolic Protection Unit, which
claims benefit of and priority to U.S. Provisional Application Ser.
No. 61/726,540 filed Nov. 14, 2012 entitled Method For Delivery Of
An Embolic Protection Unit, which is hereby incorporated herein by
reference in its entirety.
FIELD OF THE INVENTION
[0002] This invention pertains in general to the field of medical
devices. In particular the invention relates to the positioning of
catheters for the delivery of an embolic protection unit together
with a medical devices or a medical procedure, and more
specifically to the delivery of an embolic protection unit to the
aorta arch.
BACKGROUND OF THE INVENTION
[0003] This section is intended to introduce the reader to various
aspects of art that may be related to various aspects of the
present disclosure, which are described and/or claimed below. This
discussion is believed to be helpful in providing the reader with
background information to facilitate a better understanding of the
various aspects of the present disclosure. Accordingly, it should
be understood that these statements are to be read in this light,
and not as admissions of prior art.
[0004] Endovascular procedures are being used more and more
frequently to treat various cardiac and vascular surgical problems.
Blocked arteries can be treated with angioplasty, endarterectomy,
and/or stenting, using minimally invasive endovascular approaches.
Aneurysms can be repaired by endovascular techniques. Another use
for endovascular surgery is the treatment of cardiac valvular
disease. Valvuloplasties are done endovascularly and percutaneous
valve replacement is becoming an established procedure.
Transcatheter Aortic Heart Valve (TAVI) is a procedure involving a
collapsible aortic heart valve that can be manipulated into place
with minimally-invasive techniques.
[0005] Cerebral embolism is a known complication of such
endovascular procedures, and other cardiac surgery, cardiopulmonary
bypass and catheter-based interventional cardiology,
electrophysiology procedures etc. Embolic particles may include
thrombus, atheroma and lipids, plaque found in the diseased vessels
and valves that is dislodged and results in embolization. Embolic
particles may become dislodged by surgical or catheter
manipulations and enter the bloodstream. Dislodged embolic
particles can thus embolize into the brain downstream. Cerebral
embolism can lead to neuropsychological deficits, stroke and even
death.
[0006] Prevention of cerebral embolism benefits patients and
improves the outcome of these procedures. Embolic protection
devices should be compatible with the endovascular procedures, and
for instance not hinder passage through the aortic arch to the
heart.
[0007] Various embolic protection devices are known in the art.
[0008] Some embolic protection devices are disclosed in WO
2012/009558 A2, or WO 2012/085916 A2, which are incorporated herein
in their entirety for all purposes. However, these devices may
provide iatrogenic damage to the vessels in which they are
positioned. The devices also have a rather high profile in the
aortic arch, limiting the endovascular procedures.
[0009] More advantageous low profile planar devices for embolic
protection of side branch vessels of the aortic arch have for
instance been disclosed in WO 2010/026240 A1 or are described in
international patent application number PCT/EP2012/058384, which
are incorporated herein in their entirety for all purposes.
[0010] The devices may however be further improved. One issue is
that blood, that may include embolic particles, may impair
efficiency of the devices by bypassing across the device at the
periphery thereof to the carotid arteries due to insufficient
sealing at the periphery.
[0011] "Sailing" of the devices in the high pressure bloodstream
ejected out of the heart is another issue.
[0012] Hence, notwithstanding the efforts in the prior art, there
remains a need for a further improved embolic protection devices of
the type that can permit endovascular procedures, in particular of
the heart, while protecting the cerebral vasculature during the
procedures.
[0013] Further, in some instances a direct aorta approach TAVI
procedure may still be a preferred option, for example patients
with any aortic root angle be treated. Direct aortic access may be
indicated for patients with vessel diameters <6 mm, heavy
peripheral calcification, excessive tortuosity or subclavian
stenosis. The most appropriate access route should be selected by
the cardiovascular team based on patient anatomical and clinical
characteristics. Hence a protection device and a delivery device
that can be used for more than one access may be advantageous.
SUMMARY OF THE INVENTION
[0014] Accordingly, examples of the present disclosure preferably
seek to mitigate, alleviate or eliminate one or more deficiencies,
disadvantages or issues in the art, such as the above-identified,
singly or in any combination by providing a device or method
according to the appended patent claims for providing temporary
embolic protection to a patient's aortic arch vessels during
medical procedures, such as cardiac surgery and interventional
cardiology and electrophysiology procedures. Embolic particles in
the aortic blood flow are prevented from entering the aortic arch
side branch vessels, including the carotid arteries that lead to
the brain.
[0015] Disclosed herein are systems and methods for delivery of
embolic deflection.
[0016] According to one aspect of the disclosure, a method of
delivering an embolic protection unit to the aorta arch of a
patient is disclosed. The method comprises introducing a catheter
from brachiocephalic artery or through an incision in a wall of the
ascending aorta. The catheter comprises an embolic protection unit
having an off-center connection point. The method further
comprising advancing the embolic protection unit in a downstream
direction from the catheter, expanding the embolic protection unit
in the aorta arch to cover the ostia, and delivering a medical
device into the ascending aorta while the embolic protection unit
is hold by the catheter covering the ostia.
[0017] Some examples of the method includes, the embolic protection
unit is expanded to a non-tubular, substantially planar shape over
the ostia.
[0018] Some examples of the method includes, the catheter is
introduced towards the cardiac valves coaxially the ascending
aorta, or wherein the medical device is introduced towards the
cardiac valves coaxially the ascending aorta.
[0019] Some examples of the method includes, the catheter comprises
at least two channels, an elongated sheath with a first channel and
a second channel from which the embolic protection unit is
expanded, the second channel is arranged in the first channel or
around the sheath.
[0020] Some further examples of the method includes, introducing a
pigtail through one of the channels. A pigtail catheter may be
provided in such an auxiliary side channel. The pigtail catheter
may be used to further stabilize the catheter against the annulus
of the aortic valve and inner wall of the aortic arch, such as
described in WO 2012/094195 A1, which is incorporated herein by
reference in its entirety for all purposes, see in particular. A
pigtail may also be used to determine were to make the incision
when performing a direct aorta approach.
[0021] Some further examples of the method includes, the second
channel is arranged helically around the elongated sheath, and
wherein the second channel has an opening directed at an angle away
from an opening of the first channel, such as in a direction toward
aorta arch when the opening of the first channel is directed
towards the ascending aorta.
[0022] This arrangement may facilitate introducing and directing of
the collapsed embolic protection unit since the opening of the
second channel is directed towards the aorta arch and not parallel
with the first channel which may be directed coaxial with the
ascending aorta, for example when performing the direct aorta
approach.
[0023] Some further examples of the method includes, radially
expanding expandable units of the catheter or an elongated member
positioned beyond a distal end of the elongated sheath, to
temporarily position in relation to the valve the elongated sheath.
The method further includes releasing locking members of the
catheter to maintain the elongated sheath in a locked state,
delivering a medical device through the first channel to the
cardiac valve, releasing the locking members to return the
elongated sheath to a relaxed state, and withdrawing the elongated
sheath in the relaxed state from the vasculature of the
patient.
[0024] Some further examples of the method includes, inserting an
elongated member with a distal end portion comprising a plurality
of the radially expandable units, into a lumen of the elongate
sheath. Advancing the elongated member through the elongated sheath
to the distal end of the elongated sheath and retracting the
expandable units and withdrawing the elongated member from the
lumen of the elongated sheath.
[0025] Some further examples of the method includes, making an
incision in a wall of the ascending aorta upstream the introduced
catheter for introducing the medical device while the embolic
protection unit is protecting the ostia.
[0026] Some further examples of the method includes, introducing
the catheter in a direction towards the aorta arch and retracting
the catheter after expanding the embolic protection unit in the
aorta arch. Also, forwarding the catheter towards the cardiac
valves coaxially the ascending aorta and using at least one tissue
apposition sustaining unit, not being a delivery shaft of the
embolic protection unit, for application of a force offset to the
connection point at the embolic protection unit, such as a
periphery, towards an inner wall of the aortic arch when the
embolic protection unit is positioned in the aortic arch, such that
tissue apposition of the periphery to an inner wall of the aortic
arch is supported by the force.
[0027] This method is less iatrogenic than known methods. It
provides for further improved sealing of the periphery of an
embolic protection device. It further prevents creation of debris
from an ostium in the aortic arch, which might be an issue with
some known embolic protection devices.
[0028] The supported apposition is improving apposition of the
periphery to the inner wall of the aortic arch, such that the
improved apposition provides for improved sealing of the periphery
against the inner wall.
[0029] The force may be applied in a substantially proximal
direction relative the device for the improved sealing.
[0030] Applying the force may include applying a tractive force by
a traction unit. The tractive force may include pulling a periphery
of the device against the inner wall for locking the device in
place in the aortic arch. The tractive force may be applied by at
least one tether distally connected to the frame, periphery and/or
blood permeable unit for providing the tractive force.
[0031] The device may be delivered to the aortic arch via one of
the side vessels, such as the brachiocephalic artery from the right
subclavian artery, the left carotid artery, or the left subclavian
artery. It may be delivered to the aortic arch via the descending
aorta such as in a femoral approach, e.g. in a side channel of a
main catheter. It may be delivered to the aortic arch through the
wall of the ascending aorta, which is an approach called "direct
aorta" approach.
[0032] Applying the force includes applying a tractive force by a
traction unit, such a tether, or a pushing force by a pushing
unit.
[0033] Some further examples of the method include a medical device
which is a bypass machine. Also, the medical device is for a TAVI
procedure where a stent valve is delivered while the embolic
protection unit is positioned and with the catheter in the aorta
arch. Alternatively the medical device is a device for
electrophysiology.
[0034] Some further examples of the method includes, advancing the
embolic protection unit in a downstream direction from the catheter
which comprising, advancing a second catheter through a channel of
the catheter, the second catheter has a retractable sheath
enclosing the embolic protection unit and retracting the sheath
whereby the embolic protection unit expands.
[0035] The second catheter has a distal end having a bend. This may
facilitate the directing of the second catheter if the opening of
the second catheter is directed coaxial with the ascending
aorta.
[0036] Also the method may include, introducing the catheter which
includes placing a balloon mounted on the catheter with expanding
the balloon in the ascending aorta.
[0037] The balloon is a donut shaped balloon having a filter
between the catheter and the inner ring of the donut shape.
[0038] The term "sustain" as used herein means one of support, aid,
assist, keep up, uphold or the like. Sustaining a tissue apposition
of a device according to the present disclosure may be provided by
a push force or a pull force supporting, aiding or assisting
apposition, depending on the specific examples.
[0039] The term "tether" as used herein shall not be confused with
a safety tether, which is a simple safety line for allowing
retrieval of an embolic protection device if needed. A tether as
used herein is a line allowing controlled tensioning of an entire
embolic protection device or selected portions thereof. Traction is
applied proximally to the tether for the providing the tensioning
of the device to an inner vessel. The tether is distally connected
or attached to the embolic protection device such that the traction
supports anchoring of the device against the inner vessel wall. In
this manner a fluid flow at the periphery of the device is
controllable and can be totally stopped by the degree of traction
on the tether such that blood only passes a blood permeable unit of
the device.
[0040] The device including the inventive improvement of examples,
includes a collapsible embolic protection device devised for
temporary transvascular delivery to an aortic arch of a patient,
the device having a protection unit including a selectively
permeable material or unit adapted to prevent embolic material from
passage with a blood flow into a plurality of aortic side branch
vessels at the aortic arch, wherein the protection unit is
permanently or releasably (for assembly prior to introduction into
the body) attached to a transvascular delivery unit at a connection
point or region, or an attachment point, provided at the
selectively permeable unit, and a first support member for the
protection unit that is at least partly arranged at a periphery of
the selectively permeable unit. In an expanded state of the device,
the connection point is enclosed by the first support member or
integral therewith, wherein the transvascular delivery unit is
connected off-center to the protection unit at the connection
point. In some examples, the connection point or region, or
attachment point, is enclosed by the first support member.
[0041] The connection point may be provided at the selectively
permeable unit or at the first support member.
[0042] The connection point may be provided on a surface of the
selectively permeable unit devised to be oriented towards the
aortic side branch vessels from inside the aortic arch and at a
distance from the ostia regions when the protection unit is
positioned in the aortic arch.
[0043] In some examples, the selectively permeable unit includes a
first portion devised to extend in a first direction towards a
descending aorta of the aortic arch from the connection point, and
a second portion devised to extend in a second direction, opposite
to the first direction, towards an ascending aorta of the aortic
arch from the connection point, when the protection unit is
positioned in the aortic arch, in the expanded state.
[0044] In some examples, the selectively permeable unit is arranged
to asymmetrically extend from the connection point in a first
direction towards a descending aorta of the aortic arch and in a
second direction towards an ascending aorta of the aortic arch,
when the protection unit is positioned in the aortic arch, in the
expanded state.
[0045] The term "collapsible" used in the context of the present
application means that a dimension of a device is reducible to a
lesser dimension such that it is arrangeable in a tubular delivery
unit, such as a catheter. A collapsible unit is expandable when
released or pushed out of the delivery unit. Expandable includes
self expandable, e.g. by a shape memory effect and/or resilient
elasticity. A collapsible unit is the re-collapsible for withdrawal
into the delivery unit and out of the patient.
[0046] It should be emphasized that the term "including/having"
when used in this disclosure is taken to specify the presence of
stated features, integers, steps or components but does not
preclude the presence or addition of one or more other features,
integers, steps, components or groups thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0047] These and other aspects, features and advantages of which
examples of the invention are capable of will be apparent and
elucidated from the following description of examples of the
present invention, reference being made to the accompanying
drawings, in which
[0048] FIG. 1A is a schematic illustration of an elongated sheath
connected to a hemostatic valve;
[0049] FIG. 1B is a schematic illustration of an elongated member,
with the radially expandable units in the collapsed
configuration;
[0050] FIG. 2A is a schematic illustration of the distal end
portion of the elongated member with the radially expandable units
in the collapsed configuration;
[0051] FIG. 2B is a schematic illustration of the distal end
portion of the elongated member with the radially expandable units
in the expanded configuration;
[0052] FIG. 2C is a schematic illustration frontal view of the
distal end portion of the elongated member with the radially
expandable units in the collapsed configuration;
[0053] FIG. 2D is a schematic illustration frontal view of the
distal end portion of the elongated member with the radially
expandable units in the expanded configuration;
[0054] FIGS. 3A, 3B, 3C, 3D are schematic illustrations of examples
of the elongated sheath in the flexible, unlocked
configuration;
[0055] FIG. 3E is a schematic illustration of the cross sectional
view of the elongated sheath in the unlocked state;
[0056] FIG. 3F is a schematic illustration of one example of the
cross sectional view of the elongated sheath in a locked state;
[0057] FIG. 3G is a schematic illustration of another example of
the cross sectional view of the elongated sheath in the locked
state;
[0058] FIG. 4A is a schematic illustration of the elongated sheath
delivered transaxillary to a cardiac valve, where an embolic
protection filter is deployed, and the sheath is in a relaxed
state;
[0059] FIG. 4B is a schematic illustration where the relaxed sheath
is positioned in relation to the cardiac valve by expandable units
of an elongated member extending outside the distal end of the
sheath;
[0060] FIG. 4C is a schematic illustration of the cross sectional
view of the elongated sheath incorporating a second channel for
delivering the embolic protection filter;
[0061] FIG. 4D is a schematic illustration of the elongated sheath
delivered transaxillary to a cardiac valve, and the sheath is in
the locked configuration arranged relative to an aortic cardiac
valve, and the expandable units being withdrawn after positioning
the sheath;
[0062] FIG. 4E is a schematic illustration of the elongated sheath
delivered transfemorally to a cardiac valve, where an embolic
protection filter is deployed and the sheath in the locked
configuration;
[0063] FIG. 4F is a schematic illustration of the elongated sheath
delivered transaxillary to a cardiac valve, and where the relaxed
sheath is positioned in relation to the cardiac valve by expandable
units of the sheath;
[0064] FIG. 4G is a schematic illustration of the elongated sheath
delivered transaxillary to a cardiac valve, and where an embolic
protection filter is deployed over the vessels in the aortic arch
via a second channel of the sheath;
[0065] FIG. 4H is a schematic illustration of the elongated sheath
delivered transfemorally to a cardiac valve, and where an embolic
protection filter is deployed over the vessels in the aortic arch
via a second channel of the sheath;
[0066] FIG. 5 is a flowchart for a method of implanting a medical
device;
[0067] FIG. 6 is a schematic illustration of the elongated sheath
delivered transaxillary to a cardiac valve, and where an embolic
protection filter is deployed over the vessels in the aortic arch
via a second channel of the sheath;
[0068] FIG. 7A is a schematic illustration of the elongated sheath
delivering an embolic protection filter through a direct aorta
access;
[0069] FIG. 7B is a schematic illustration of the elongated sheath
delivered through a direct aorta access to a cardiac valve, and
where an embolic protection filter is deployed over the vessels in
the aortic arch via a second channel of the sheath;
[0070] FIG. 8A is a schematic illustration of the elongated sheath
delivered transaxillary to a cardiac valve, and where an embolic
protection filter is deployed over the vessels in the aortic arch
using a retractable sheath via a second channel;
[0071] FIG. 8B is a schematic illustration of the retractable
sheath advanced from the second channel;
[0072] FIG. 8C is a schematic illustration of the retractable
sheath when retracting and the embolic protection filter is
expanding;
[0073] FIG. 9A is a schematically illustration of a sheath with a
second channel helically arranged at the sheath; and
[0074] FIG. 9B is a schematic illustration of the elongated sheath
delivered through a direct aorta access to a cardiac valve, and
where an embolic protection filter is deployed over the vessels in
the aortic arch via a second channel helically arranged at the
sheath.
DESCRIPTION OF EMBODIMENTS
[0075] Specific examples of the disclosure will now be described
with reference to the accompanying drawings. This disclosure may,
however, be embodied in many different forms and should not be
construed as limited to the examples set forth herein; rather,
these examples are provided so that this disclosure will be
thorough and complete, and will fully convey the scope of the
invention to those skilled in the art. The terminology used in the
detailed description of the examples illustrated in the
accompanying drawings is not intended to be limiting of the
disclosure. In the drawings, like numbers refer to like
elements.
[0076] In an example of the disclosure according to FIG. 1A, a
catheter device 1 for transvascular delivery of a medical device to
a cardiac valve region 6 (see e.g. FIG. 4D) of a patient is shown.
The catheter device comprises an elongated sheath 2 with a lumen
and a distal end 3. In addition, in FIG. 1B an elongated member 4
is provided with a distal end portion 9 comprising a plurality of
radially expandable units 5. The end portion 9 may include an
obturator. The expandable units 5 are arranged for temporarily
positioning the elongated sheath 2 in relation to the cardiac valve
6, FIGS. 4B and 4F. The elongated member 4 is retractably
insertable into the lumen of the elongated sheath 2 and the
elongated sheath 2 comprises releasable locking members for
controllably locking the elongated sheath 2 in a shape at least
partly along its length from a relaxed state (See FIG. 3B, and FIG.
4A-B, 4F) to a locked state (See FIG. 3C-D, and FIG. 4D-E, 4G-H)
when positioned in relation to the cardiac valve 6 by the
expandable units 5.
[0077] The elongated sheath 2 depicted in FIG. 1A is designed to be
deliverable transvascularly in the relaxed state which facilitates
optimal flexibility when transiting through the vasculature. When
at the desired anatomical location the elongated sheath 2 is able
to transit from the relaxed state to the locked state by activation
of the locking members, when positioned in relation to the cardiac
valve 6, as seen in FIG. 4D-E, by the expandable units 5, which
facilitates optimal stabilization of the catheter 1 for
subsequently affixing the medical device to the heart valve 6.
[0078] FIG. 4A shows the elongated sheath inserted in its relaxed
shape. FIG. 4B shows the radially expandable units 5 in their
expanded configuration, i.e. outside the elongated sheath 2, which
positions the elongated sheath 2 centrally over the valve 6. The
expandable units 5 expand out of the elongated member 4, which
extends beyond the distal end of the sheath 2. Thereafter the
elongated sheath 2 is brought to its locked state by locking
members, and the elongated member 4 is retractable from the lumen
of the elongated sheath 2 together with the plurality of radially
expandable units 5 when collapsed, as seen in FIGS. 4D-E. The
sheath 2 is now positioned and stabilized over the valve 6. This
overcomes the problems in prior art with insufficient stabilization
and lack of accurate positioning. Merely providing an expandable
catheter could not provide stabilization as with the locking
members of the sheath 2. Expandable catheters have another purpose,
which is providing an accessible lumen or dilating septum
punctures. Further, expandable members of previous catheters are
merely for providing aforementioned expansion and not for
positioning the catheter centrally over a valve as provided by
catheter 1. When the elongated sheath 2 is locked and, when the
elongated member 4 is retracted, the lumen of the elongated sheath
2 is accessible for delivery of a medical device to the cardiac
valve 6 region.
[0079] Alternatively, or in addition, expandable units, such as
balloons may be arranged on the outside of the sheath 2. The
expandable unit may be integrally formed with the sheath, as seen
in FIG. 4F. Thus, the expandable units do not affect the cross
section of the lumen of sheath 2. Upon returning to the unexpanded
state, e.g. by deflating balloons of the expandable units 5, a
delivery of a medical device through the catheter lumen may be made
without the need to retract the expandable units 5.
[0080] The expandable units provide for a defined positioning of
the distal end of the catheter sheath 2 in an anatomical structure,
like a blood vessel, an atrium or cardiac chamber, relative a
cardiac valve. This allows for a precision delivery of a medical
device through the catheter device. Movements of certain anatomical
structures are very limited over the cardiac cycle. For instance
the aortic arch is relatively stable and the locked catheter will
stay substantially in the same spatial orientation, direction, and
distance to the cardiac valve as during the final positioning
provided by the expanded expandable units 5.
[0081] The catheter may thus be positioned relative a cardiac valve
in an anatomical structure.
[0082] The catheter may be locked in the locked configuration along
its entire length. Alternatively, it may only be locked along a
distal portion thereof. A distal portion may for instance be the
portion arranged in the ascending aorta, the aortic arch and the
descending aorta, as shown in FIG. 4E. The catheter may comprise an
embolic protection unit 8, such as an embolic protection filter 8.
The embolic protection unit 8, when protruding out of the second
lumen 7 and being in apposition against the surrounding vessel
wall, may further contribute to stabilizing the distal end of the
locked catheter in place relative to the cardiac valve. Hence, when
the embolic protection unit 8 is expanded it will function as an
anchor to the sheath because it prevents movement of the sheath 2
in the aortic arch due to the second channel 7, from which the
embolic protection unit expands, is fixed to the sheath. The
delivery unit 13 for the embolic protection unit 8 has sufficient
rigidity to allow an anchoring function for the sheath 2. The
embolic protection unit 8 provides stabilization and anchoring of
the sheath 2 irrespectively whether the sheath 2 is in a relaxed
state or in a locked state. Further, the embolic protection unit 8
provides stabilization and anchoring of the sheath 2 irrespectively
whether expandable units 5 are used. Hence, it is not essential for
the sheath 2 to have the locking members, the elongated member 4,
or the expandable units 5, in order to provide the advantageous
effects as described, see further below.
[0083] FIG. 4D is a schematic illustration of the elongated sheath
delivered transaxillary to a cardiac valve, here the aortic valve
6. The embolic protection filter 8 is deployed, and the sheath 2 is
in the locked configuration arranged relative to an aortic cardiac
valve 6.
[0084] FIG. 4E is a schematic illustration of the elongated sheath
delivered transfemorally to a cardiac valve, where an embolic
protection filter is deployed and the sheath in the locked
configuration.
[0085] In FIGS. 4D and 4E, the expandable units 5 are not shown, as
they are either retracted from the sheath, or returned to their low
profile unexpanded/collapsed configuration in the sheath.
[0086] In FIG. 4G-H the embolic protection filter 8 is positioned
over two or three of the vessels in the aortic arch,
respectively.
[0087] In all configurations shown in FIGS. 4A-B, 4D-H, the side
vessels 22 are effectively protected from embolic particles
entering from the aortic arch. Embolic particles are carried with
the blood flow past the embolic protection device along the aortic
arch to anatomical structures that are less sensitive than e.g. the
brain to which some of the side vessels 22 lead the blood flow.
Embolic protection units may be filter units in which the embolic
particles are caught. Alternatively, or in addition, the embolic
protection units may provide for the particles to slide along the
protection unit, but not pass it or fasten in it.
[0088] In examples, such as illustrated in FIG. 4A-H a catheter 1
having a second channel 7 that extends parallel on the outer
portion or the inner portion of the elongated sheath 2 is depicted.
This channel 7 allows for the delivery of further units for example
an embolic protection device 8 or liquids to aid the procedure to
place the medical device, when the lumen of the elongated sheath 2
is used for the elongated member 4 or medical device.
[0089] The second channel 7 may be an integral part on the inside
or outside of the elongated sheath 2. This has the advantage of
being relatively cheap to manufacture by an extrusion method.
[0090] In FIGS. 4A-H, an expandable embolic filter 8 example is
depicted. The embolic protection or filter device 8 may be extended
before extending the aforementioned expandable units 5. This
potentially enhances patient safety by capturing any emboli such as
plaque debris produced from the treatment of a stenotic valve, and
thus reduces the chance for serious complications such as stroke.
In these figures at least a portion of the expandable embolic
filter 8 extends from the orifice of the side channel 7 through
which the embolic filter 8 is passed. The embolic filter may be of
the type as disclosed in WO 2010/026240, which is incorporated
herein in its entirety for all purposes. The embolic filter unit
may be non-tubular, extending substantially planar in the expanded
state. This provides for a compact device and efficient blocking of
side branch vessels in the aortic arch from embolies. Interaction
with the side walls in the aortic arch is therefore also kept at
the minimum, avoiding scraping off further debris to be transported
with the blood stream. Simultaneously, the aortic arch is kept open
for unrestricted navigation of the sheath 2. Hoop shaped baskets in
previous devices scrapes against the vessel wall and blocks a
substantial portion of the navigational space in the aortic
arch.
[0091] Extending "planar" in this context means that the thickness
of the device is substantially smaller than the longitudinal
extension thereof. Moreover, "planar" means such dimensions
perpendicular to the longitudinal extension of the protective
material, that blood flow through the aortic arch is not hindered
by the protective device.
[0092] By having a second channel in the sheath 2, the distal end
of the sheath can be positioned appropriately at the valve, by the
stabilizing and anchoring effect of the protection unit 8 extending
from the second channel, while medical device can be delivered
through the lumen of the sheath without any hindrance from the
protection unit 8 or e.g. expandable units such as balloons, while
at the same time the side branch vessels of the aortic arch are
protected from embolies that may be transported in the blood stream
from the procedure performed at the valve.
[0093] The catheter device 1 may comprise a delivery unit 13
connectable to the embolic filter unit 8 at a connection point 14,
as illustrated in FIGS. 4G-H. The connection point 14 is arranged
off-centre at the embolic filter unit such that the delivery unit
13 is connectable off-center to the embolic filter unit 8. The
off-centre position of the embolic filter unit is advantageous for
deploying it with the sheath 2 via the delivery unit 13, while
efficiently protecting the carotid arteries from embolies, when
carrying out the intervention. Blood flow is kept open efficiently
by such compact device. The term "off-centre" used in the context
of the present application means eccentric, or not arranged or
located in a center of the device. The center is e.g. a center of a
circular unit, a focal point of an elliptical unit, a point on a
center line, such as a longitudinal center line of an elongated
unit, etc. A periphery of a unit is located "off-centre" as it is
arranged at a distance in relation to a center of the unit.
[0094] The elongated member 4 may be comprised of three balloons
positioned radially equidistant around the longitudinal axis (See
FIG. 2C and D). Fewer or more balloons are possible, as well as
alternative expansion units such as expandable mechanical levers,
or swellable units for example retractable sponges. The expansion
units 5 allow for optimal positioning of the elongated sheath 2 in
relation to the aforementioned cardiac valve 6. The multiple
balloon expansion unit can be expanded (See FIG. 2D) using a
variety of means for example using a fluid means or where
appropriate gaseous means. The balloons can also be individually or
simultaneously expanded as well as inflated to differing pressures
independently of the other expanding units.
[0095] Alternatively, the elongated member 4 is retractably
inserted into the lumen of the elongated sheath 2 to a length equal
to the distance between the distal end 9 and the second proximal
marker 10. In this example, proximal markers 10 and 11 are used to
guide the positional orientation of the distal end portion 9 and
thus provide for optimal alignment of the expandable units 5 with
the portion of the elongated sheath 2 to be expanded. This
facilitates safe positioning at the desired valve region.
[0096] In a further example, the elongated sheath 2 is comprised of
radiopaque material, facilitating visualization of the elongated
sheath 2 which provides for optimal positioning of the elongated
sheath 2 for delivery of the medical device. Alternatively,
radiopaque fiducial markers on the elongated sheath 2 can be used
for optimal positioning of the sheath 2 within the body of the
patient.
[0097] The example shown in FIGS. 2A and 2B, includes a guide wire
12 which is firstly positioned within the patient which facilitates
optimal transit of the elongated sheath 2 and elongated member 4 to
the desired anatomical site.
[0098] In the examples of FIGS. 3-4, the locking units may comprise
releasable latches although any one from draw strings, squeezing
mechanisms, or the like could be envisaged as being used to lock
the elongated sheath 2 in a locked state, i.e. a rigid or
semi-rigid state of the sheath that allows the sheath 2 to maintain
a specific curvature, i.e. reduction in flexibility, and thereby
secure its position relative to the anatomy, as seen in e.g. FIG.
4D-E. Further, thermal, electrical, magnetic or chemical properties
of the material of the locking units or the elongated sheath 2
itself, may provide variable flexibility for changing between a
locked state and a relaxed state.
[0099] In a specific example, the elongated sheath may be expanded
when in locked configuration. Releasing of locking units when the
elongated sheath 2 is in an expanded state locks the elongated
sheath 2 in the expanded state and thus retains the optimal
position for medical device positioning through the procedure.
[0100] The locked elongated sheath 2 may be used in medical
procedures to delivery of a medical device to the cardiac valve 6,
which could include artificial heart valve prosthesis, an
annuloplasty device or leaflet clips.
[0101] The elongated sheath 2 maybe a constituent of a medical
system devised for transvascularly delivering a medical device to a
cardiac valve 6 of a patient. The method as depicted in FIG. 5
initially comprises 100 minimally invasively either transfemorally
(See FIG. 4E) or transaxillary (See FIG. 4D) introducing a catheter
1 comprising an elongated sheath 2 with a lumen in a relaxed state
into the patients vascular system. Step 110 involves the distal end
3 of the elongated sheath 2 being navigated through the vascular
system to the desired cardiac valve, FIG. 4A. The next step in the
system 120, involves the elongated member 4 with a distal end
portion 9 comprising a plurality of radially expandable units 5,
being inserted into the lumen of the elongated sheath 2, whereupon
it is advanced through the elongated sheath 2 to the distal end of
the elongated sheath 2, FIG. 4B. Alternatively, expandable units 5
of the sheath may be expanded at this stage (without introducing an
elongated member 4 into the sheath, FIG. 4F. Whereupon step 130 is
initiated which involves the plurality of radially expandable units
5, being radially expanded to temporarily position in relation to
the cardiac valve 6 the elongated sheath 2, (See FIG. 4B and
4F).
[0102] Following positioning, the locking members of the catheter
are released to maintain the elongated sheath 2 in a locked state
(step 140). Step 150 of the system can then be performed whereby
the expandable units 5 are then retracted and the elongated member
4 is withdrawn from the lumen of the elongated sheath 2, FIG. 4D-E.
Alternatively, the expandable units 5 of a sheath 2 are brought
back to the non-expanded state.
[0103] The embolic protection unit as shown in FIGS. 4A-H, may then
be advanced out of the second channel 7. In this manner, side
vessels are protected from embolic material, such as debris.
[0104] A medical device can now be delivered through the lumen of
the locked elongated sheath 2 to the heart valve 6. This delivery
is done with high spatial precision. Blood flow in the lumen around
the locked elongated sheath 2 is affected less than with expanded
expandable units 5.
[0105] The medical device may for instance be a cardiac valve
repair or replacement device.
[0106] When the medical device is delivered, release of the locking
members to return the elongated sheath 2 to the relaxed state can
now be performed (step 160) with the subsequent withdrawal of the
elongated sheath 2 in the relaxed state from the vasculature of the
patient.
[0107] The embolic protection unit as shown in FIGS. 4A-H may be
retracted prior or after the release of the locking members.
[0108] Locking of the elongated sheath 2 in the locked state (FIG.
3B-D) comprises releasing the locking members for controllably
locking the elongated sheath 2 when positioned in relation to the
cardiac valve 6 by the expandable units 5. This serves to retain
the optimal position for delivery of the medical device during the
procedure.
[0109] To ensure the optimal positioning of the elongated member 4
when it is inserted into the elongated sheath 2, the elongated
member 4 is inserted to a length which is equal to the distance
between the distal end and the second proximal marker 10 of the
elongated member 4. Primarily the elongated sheath 2 will be
centrally positioned in relation to the cardiac valve 6, which
facilitates optimal delivery of the medical device, although other
positions off-center could also be desirable.
[0110] The medical system is primarily used for the delivery of a
medical device to be affixed to the particular cardiac valve 6,
which include the aortic and mitral valves of a patient. After
delivery of the medical device to the cardiac valve 6, the medical
device delivery system is withdrawn through the lumen of the locked
elongated sheath 2, which may be aided if the elongated sheath 2 is
in an expanded state. After removal of the medical device delivery
system, the elongated sheath 2 in the locked state transits to the
relaxed state which facilitates enhanced retraction of the
elongated sheath 2.
[0111] FIG. 6 illustrates an example of using a catheter having two
channels, as described herein above, for delivering a embolic
protection unit from the brachiocephalic artery, such as from the
right subclavia artery or the right common carotid artery. The
elongated sheath 2 is advanced into the ascending aorta and may be
used to deliver a medical device for a medical procedure. Medical
procedures on the heart may includes at least a step related to
removal of a heart valve, the placement of a prosthetic heart
valve, or repair of a heart valve. This may include the treatment
of cardiac valvular disease, like valvuloplasties including
percutaneous valve replacement. The procedure may be Transcatheter
Aortic Heart Valve (TAVI) involving implantation of a collapsible
aortic heart valve with minimally-invasive techniques. It may also
relate to bypass, cardiac surgery, interventional cardiology or
electrophysiology procedures.
[0112] An apposition sustaining unit may be used to apply a force
offset to the connection point at the device. Offset to the
connection point may for instance be at the periphery. It may also
be adjacent the periphery. It may also be centrally of the blood
permeable unit within the periphery. The force is applied or
directed towards an inner wall of the aortic arch when the device
is positioned in the aortic arch. In this manner tissue apposition
of the periphery to an inner wall of the aortic arch is supported
by the force. For instance, a tractive force such applied may pull
a periphery of the device against the inner wall. The force
supports locking the device in place upon implantation.
[0113] The embolic protection device can thus be reliably placed
across the apex of the aorta in order to prevent emboli from
flowing into the carotid arteries. The inventive solution is not
iatrogenic, as it prevents creation of debris from e.g. ostia of
side vessels. Iatrogenic relates to an adverse condition in a
patient resulting from treatment by a physician or surgeon. Arms,
anchors, delivery shafts, bows, etc. of inferior embolic protection
devices, for instance extending into the side vessels, risking
scraping off of plaque from the inner vessel wall or ostia, are not
needed and can be avoided thanks to the present disclosure.
[0114] In the example of FIG. 6 a tether 40 which may run in the
same channel or in other channels of the catheter as the embolic
protection unit 8 and be used to apply a tractive force. The
apposition supporting unit may then be an active traction unit that
has for instance at least one operable tether distally connected at
the location offset the connection point. The distal connection
location of the tether may be located at the frame, periphery
and/or blood permeable unit, of the embolic protection device for
providing the tractive force. The tether has one or more distal
end(s). The distal end is for instance connected to the periphery
of the embolic protection device. The tether's distal end(s) may be
connected to the blood permeable unit, such as a filter or
deflector membrane. The membrane may be moved by the traction, e.g.
if the membrane is flexible and/or elastic.
[0115] Tether(s), or more precisely, tetherline(s) are provided to
control a sealing degree of the periphery. Tether(s) are provided
for direction of apposition towards aortic tissue/cerebral
arteries. The tether may provide active traction by a pull action
on the tether communicated to the embolic protection device to
which it is distally connected.
[0116] The tether 40 may be arranged longitudinally movable
relative the delivery unit. In this manner, the device is
positionable in the aortic arch so that the delivery device may be
locked in a "delivered" position, by the delivery unit, e.g. at its
proximal end at or outside a port of an introducer. The tether 40
may then still be movable and improve sealing as described
herein.
[0117] Tether(s) may be multifilament(s), which provides for a
particularly flexible solution advantageous for narrow lumen
navigation.
[0118] A tether 40 may extend straight across the blood permeable
unit to the forward end of the device. Thus the middle line may be
pulled up and the periphery is tensioned against the inner wall.
The tether provides for a lifting force to the forward end. In case
the tether is guided at the middle line, e.g. threaded through
eyelets, it may provide a progressive lifting force distributed
along the device.
[0119] The at least one tether 40 may be longitudinally elastic,
i.e. it is longitudinally stretchable and resiliently return to a
non-stretched longitudinal extension. The tether may be elastic
along its entire length. The tether may include one or more elastic
portions or elastic elements. The elastic portion may be a helical
wound portion of the tether acting as a spring. The elastic portion
may be a tubular braid of a double helically wound strands. The
elastic portion may be made of an elastic material, preferably
biocompatible, like rubber. In this manner the tractive force is
variable. This may be advantageous for preventing rupture of the
tether line as a non-linear extension may be "felt" by an operator.
This variable traction force may also be advantageous if the tether
is tension, applying a desired traction for improving sealing of
the embolic protection device. The tether may be locked at its
proximal end in this position, e.g. extending out of an introducer
port. The elasticity may provide for compensating physiological
movements of the aortic arch relative a proximal end of the device
and/or tether while maintaining the tissue apposition. The applied
force is provided within a certain range suitable to maintain the
improved peripheral sealing while the aortic arch moves due to the
beating heart and blood pulse waves.
[0120] The blood permeable unit of the embolic protection device
may have at least one guiding unit, such as an eyelet, a tubular
bent element, a roller, an open pocket fabric portion, etc. The
guiding unit may receive the tether proximally its distal end where
it is attached to the device, such as at the blood permeable unit,
flange, or periphery. The guiding units, such as eyelet(s) etc.
provide for locally controllable apposition at the device. The
traction force may be distributed to different areas of the
device.
[0121] The device may have an attachment point where a distal end
of the tether is connected to the device and a tractive force is
transmissible via the attachment point to the device towards the
periphery. Optionally one or more radiopaque fiducial markers may
be provided at the device. A fiducial marker may be provided at the
attachment point. Fiducial markers provide for advantageous X-ray
visibility and navigation, position feedback and control of the
device.
[0122] In some examples, the tether is proximally extending through
an ostium into a selected side vessel such that the tractive force
centers the device in relation to the ostium. When pulling the
tetherline 40, it pulls the device at its periphery against the
inner wall of the aorta for locking the device in place. In this
manner the device is self aligning in relation to the ostium of the
selected side vessel thanks to the tether. The skilled person may
provide suitable guiding units for the tether when reading this
disclosure to obtain this function.
[0123] The device may include multiple tethers distally attached
along the periphery. Alternatively, or in addition, a single
proximal tetherline may separate distally into a plurality of
(sub)tetherlines. For instance, a tether may be branched in the
form of a Y. A single tether to be operated proximally may then
distribute a tractive force distally via its two distal end points
to the embolic protection device.
[0124] Multiple tethers may be used or combined with tethers having
multiple distal ends. The multiple tethers may be collected
proximally at the device, e.g. at a base thereof. In this manner,
the device provides for a progressive force that is evenly
distributed along the periphery of the device. The device may in
this manner advantageously adapt to the inner shape of the aortic
arch. The adaptation may even more enhanced by providing
longitudinally elastic portions at the tether(s). For instance, the
branched (sub)tetherlines may be provided of elastic material,
while the main line is substantially non-elastic, but flexible.
[0125] In some examples, the device may have at least one rib
extending between different, preferably opposite, joints at the
periphery, wherein the tether is distally attached at the rib. The
tether 40 may thus apply a tractive force to the rib, which in turn
transfers the force to the periphery of the device 8 towards the
aortic inner wall tissue. The rib may be a beam or yoke. It may be
arranged longitudinal or transversal in relation to the expanded
device's 8 longitudinal axis.
[0126] FIG. 7A illustrates a "direct aorta" approach were an
incision is made through the wall of the ascending aorta. This is
done by making a mini-sternotomy or mini-thoracotomy. In the
mini-thoracotomy a incision is made in the intercostal space. For
TAVI, the direct aorta approach can be used in patients with any
aortic root angle. Direct aortic access may be indicated for
patients with vessel diameters <6 mm, heavy peripheral
calcification, excessive tortuosity or subclavian stenosis. The
most appropriate access route should be selected by the
cardiovascular team based on patient anatomical and clinical
characteristics.
[0127] In FIG. 7A, the embolic protection unit 8 is introduced into
the aortic arch with one catheter 2 through an incision in the
wall. A second incision is positioned upstream the incision used
for introducing a medical device or performing a medical procedure.
Additionally, the embolic protection unit may have an apposition
sustaining unit, such as a tether 8.
[0128] Alternatively the brachiocephalic artery may be used for
introducing a sheath 2 or catheter for advancing the embolic
protection unit into the aorta arch while a incision is used for
introducing a medical device or performing a medical procedure.
[0129] In FIG. 7B illustrates an example of using a catheter having
two channels, as described herein above, for delivering an embolic
protection unit 8 using the direct aorta approach. The first
channel 2 is used for delivering a medical device or performing a
medical procedure while the second channel 7 is used for
introducing the embolic protection unit 8. In the illustration of
FIG. 7B, the apposition sustaining unit is applying a pushing force
by a pushing unit 45. A pushing unit is similar to the traction,
such as a tether, as described herein above. But instead of a
tractive force a pushing force is applied from beneath the embolic
protection unit 8. The pushing unit 45 applies pushing force
against the frame, periphery and/or blood permeable unit. Thus the
pushing force and presses the periphery to the inner wall. This can
be done either with a single wire or multiple wires (as shown in
the FIG. 7B). The wires may be connected to the embolic protection
unit 8 in the same fashion as the tethers described herein.
[0130] FIG. 8A-C illustrates an example of using a catheter having
two channels 2 and 7 introduced from the brachiocephalic artery. In
this example, when advancing the embolic protection unit 8, in a
downstream direction from the catheter, a second catheter is pushed
out of the second channel 7. This second catheter has a retractable
sheath 46 enclosing the embolic protection unit 8. When the
retractable sheath has reach its correct location the sheath is
retracted where after the embolic protection unit expands.
[0131] Additionally and/or alternatively to the tether 40
illustrated in FIG. 8C any type of sustaining unit can be used such
as a pushing unit.
[0132] Additionally, as illustrated in FIG. 8A-C, the retractable
sheath has a bent distal end. This may facilitate directing the
retractable sheath into the aorta arch.
[0133] The same approach using a retractable sheath can be applied
on the direct aorta approach or when introducing an embolic
protection unit 8 through any of the other accesses, such as the
left subclavian artery, or the descending aorta such as in a
femoral approach.
[0134] FIG. 9A-B, illustrates another example of how the directing
of the embolic protection unit 8 into the aorta arch may be
facilitated. In this example, the second channel 7 is arranged
helically around elongated sheath 2. Thus the opening 47 of the
second channel may be directed at an angle away from an opening of
the first channel of the elongated sheath 2, towards the aorta
arch.
[0135] Additionally, this arrangement may be used with a
retractable sheath as described in relation with FIG. 8A-C.
[0136] FIG. 9B illustrates a direct aorta approach but this may be
used when introducing a catheter from the brachiocephalic
artery.
[0137] Additionally to what has been described above, delivering of
the embolic protection device may be made transluminally, and
delivering the first catheter may be performed after the delivering
the embolic protection device.
[0138] Delivering the first catheter may include placing a balloon
mounted on the first catheter with expanding the balloon in the
ascending aortic arch to lock a distal end of the first catheter in
place. The balloon may have a donut shape having a filter between
the catheter and the inner ring of the donut shape.
[0139] The embolic protection device used in the method may extends
from a distal end of a second catheter or separate channel of the
first catheter, such that the position of the embolic protection
device can be independently adjusted from the position of the first
catheter.
[0140] Delivering a first catheter may be performed concurrently
with delivering the embolic protection device via a separate
channel of the first catheter, independent of the endovascular
procedure.
[0141] The present invention has been described above with
reference to specific examples. However, other examples than the
above described are equally possible within the scope of the
invention. Different method steps than those described above, may
be provided within the scope of the invention. The different
features and steps of the invention may be combined in other
combinations than those described. The catheter may be positioned
and locked in other cardiac anatomical structures than illustrated.
Medical devices delivered through the catheter sheath may be any
medical device to be delivered to the cardiac valve tissue. The
scope of the invention is only limited by the appended patent
claims.
* * * * *