U.S. patent application number 10/806939 was filed with the patent office on 2005-01-06 for exitable lumen guide wire sheath and method of use.
Invention is credited to Khaw, Kenneth.
Application Number | 20050004645 10/806939 |
Document ID | / |
Family ID | 27659438 |
Filed Date | 2005-01-06 |
United States Patent
Application |
20050004645 |
Kind Code |
A1 |
Khaw, Kenneth |
January 6, 2005 |
Exitable lumen guide wire sheath and method of use
Abstract
The present invention is directed to an apparatus for and method
of treatment or vascular procedures. An exitable lumen guide wire
sheath is disclosed and advantages thereof. The exitable lumen
guide wire sheath and method may be used as a multiple exitable
lumen or single exitable lumen. A method of treatment of multiple
branch vascular lesions is disclosed in which a desired branch of a
multiple branch lesion may be protected for further procedures by
an interventionalist or other practitioner. Other combinations and
uses for the disclosed invention will be apparent to those skilled
in the art.
Inventors: |
Khaw, Kenneth; (Plainsboro,
NJ) |
Correspondence
Address: |
Licata & Tyrrell P.C.
66 E. Main Street
Marlton
NJ
08053
US
|
Family ID: |
27659438 |
Appl. No.: |
10/806939 |
Filed: |
March 23, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10806939 |
Mar 23, 2004 |
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10072276 |
Feb 6, 2002 |
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6746411 |
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Current U.S.
Class: |
623/1.11 |
Current CPC
Class: |
A61F 2/958 20130101;
A61M 2025/0037 20130101; A61F 2/954 20130101; A61M 25/0043
20130101; A61M 25/09 20130101; A61M 2025/0035 20130101; A61F
2250/006 20130101; A61F 2002/065 20130101; A61F 2/856 20130101 |
Class at
Publication: |
623/001.11 |
International
Class: |
A61F 002/06 |
Claims
1. (canceled).
2. An apparatus for treating multi-branch vascular lesions
comprising: a selected length of an exitable lumen guide wire
sheath; a stent; and a balloon catheter.
3. The apparatus of claim 2 wherein the balloon catheter contains a
shaft.
4. The apparatus of claim 2 wherein the selected length of the
exitable lumen guidewire sheath is coupled to the balloon catheter
shaft.
5. The apparatus of claim 2 wherein a portion of the selected
length of the exitable lumen guide wire sheath is inserted through
a portion of the stent.
6. The apparatus of claim 5 wherein the stent has been predilated
to accept the portion of the selected length of the exitable lumen
guide wire sheath and then crimped to capture the portion of the
selected length of exitable lumen guide wire sheath in the
stent.
7. A method for treating a multiple branch lesion comprising the
steps of: gaining access to a major vessel; inserting a first guide
wire toward the multiple branch lesion; inserting another guide
wire for each additional branch to be treated; and delivering a
intra-vascular medical device with a selected length of exitable
lumen guide wire sheath.
8. The method of claim 7 wherein the multiple branch lesion has
been pre-identified.
9. The method of claim 7 wherein the intra-vascular medical device
with a selected length of exitable lumen guide wire sheath is
comprised of the selected length of exitable lumen guide wire
sheath coupled to the shaft of a balloon catheter and inserted
through a portion of a stent on the balloon catheter and the
selected length of exitable lumen guide wire sheath.
10. The method of claim 9 wherein the selected length of exitable
lumen sheath may contain a multiple of exitable lumens.
11. The method of claim 9 wherein the stent is crimped to capture
the selected length of exitable lumen guidewire sheath.
12. The method of claim 7 wherein the intra-vascular medical device
with a selected length of exitable lumen is back loaded on to the
guide wires and advanced to the multiple branch lesion.
13. The method of claim 7 wherein the medical devise with the
selected length of exitable lumen guidewire sheath is positioned at
the multiple branch lesion such that the selected length of
exitable lumen guidewire sheath enters a desired branch of the
multiple branch lesion.
Description
PRIORITY CLAIM
[0001] This application is a Continuation of U.S. patent
application Ser. No. 10/072,276, filed Feb. 6, 2002, now pending,
and which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The invention is directed vascular medical procedures using
catheters and/or guide wires.
BACKGROUND OF THE INVENTION
[0003] The state of the art in cardiovascular, and vascular
procedures in general, is at the forefront of interventional
medicine procedures designed to prolong life and add to the quality
of life. Interventional medicine, whether performed by an
interventionalist specialist or other practitioner, is an advancing
and beneficial science. For many people, a healthy and sustained
existence is in constant jeopardy due to clogged, narrowed,
sclerosed or damaged vasculature. This is especially true of the
cardiovasculature and peripheral vasculature. Interventional
medicine is designed to address these and other problems.
[0004] Commonly, a vessel may become stenotic, or narrowed. One of
the most familiar and common etiologies of this stenosis is
atherosclerosis. Atherosclerosis is a thickening and hardening of
medium and larger arteries with narrowing of the arterial lumen by
atherosclerotic plaques; its cause is multifactorial. See,
Andreoli, Carpenter, Plum and Smith, Cecil, Essentials of Medicine
(W. B. Saunders Co. 1986). Other causes of stenosis include injury,
syphilis, polyarteritis nodosa, Takayasu's disease, disseminated
lupus erythematous, rheumatoid arthritis and other arteritis. Id.
There is also continuing evidence that timely Percutaneous
Transluminal Coronary Angioplasty (PTCA) is superior to other
treatments in patients with acute myocardial infarction. See,
Sutsch, Amamn, To Stent or Not to Stent, Schweiz. Med. Wochenchr.
1999; 129:1979-96
[0005] Blood flow volume through a stenotic vessel is slowed and
restricted or "backed up" proximal to the stenosis. This can be
further complicated by mechanical, chemical and immunologic injury.
The intimal surface of the vessel may ulcerate, thrombose and
occlude the lumen of the vessel. This leads to decreased
nourishment and oxygenation of the distal tissues and can
ultimately lead to necrosis.
[0006] Further, and consistent with Bernoulli's law, the velocity
of the blood flow is inversely proportional to the pressure exerted
by the side of the vessel. In other words, the velocity is greatest
and the pressure is lowest at the point of maximum stenosis. This
fact has important ramifications as the increased velocity leads to
increase turbulence in the flow distal to the stenosis. This, in
turn, increases the ability of deposits, i.e. atherosclerotic
plaques, to adhere to the vascular intima. In a similar phenomenon,
plaques tend to occur at arterial bifurcations, again due to the
turbulent flow in the area. The phenomenon is routine at branch
sites, i.e. bifurcation and trifurcation of vessels or any multiple
branching of a vessel. A common site of bifurcation of vessels is
in the coronary vascular anatomy.
[0007] It is well known that the coronary arteries are markedly
susceptible to atherosclerosis. This is especially true within the
first six centimeters of origin of the vessel. Additionally,
coronary arteries have multiple bifurcations. For example, the
right and left coronary arteries bifurcate and branch as they
descend the myocardium. Common sites for stenosis include the left
coronary artery bifurcation to the circumflex and anterior
interventricular (descending) artery; right coronary artery to the
posterior interventricular and right marginal arteries; and
bifurcations associated with the crux and marginal arteries.
Further, any vessel of the body that suffers the effects of
atherosclerosis can stenose and become a candidate for treatment,
particularly in the peripheral vessels.
[0008] Treatment mechanisms for stenotic vessels have range from
and include chemotherapy, radiation, Coronary Artery Bypass
Grafting (CABG), angioplasty, rotational cutting devices to remove
plaque formation and laser treatments. Each treatment has
individual indications and contraindications. Additionally, each
treatment modality has its own attendant risks. CABG of blocked or
stenotic vessels is the least conservative, most expensive, most
painful and is attended by the most serious complications. Surgery
also requires the longest convalescence. See, Sutsch, Amamn, To
Stent or Not to Stent, Schweiz. Med. Wochenchr. 1999; 129:1979-96.
Chemotherapy and radiation treatment both have unwanted side
effects. Currently, one of the safest and most effective treatments
of stenotic vessels is percutaneous angioplasty. A common example
of this is PTCA.
[0009] In the procedure, considered a non surgical interventional
radiological procedure, a balloon catheter is placed in a diseased
vessel through a small incision in to a main vessel; the femoral
artery, for example. The catheter is tipped with a balloon at the
end which can be inflated within the stenotic vessel to make the
vessel patent. In order to guide the catheter to the diseased
vessel and its stenosed portion, the catheter is placed over a
steerable guide wire.
[0010] Inflation of the balloon is often all that is needed to make
the stenotic vessel patent, but more often a stent is used to
maintain patency of the vessel. A stent is a type of intra-vascular
medical device used to maintain a bodily orifice or cavity after
placement. Usually, a stent is comprised of an interconnected mesh
of non-absorbable surgical grade material that, after placement,
lies within the lumen of tubular structures and is used to provide
support. Very commonly, a stent is used after dilation of an
atherosclerotic coronary or peripheral vessel with a balloon
catheter.
[0011] PTCA, with or without stent deployment, is performed
commonly all over the world. Multiple vessels throughout the
anatomy are treated. See, Sutsch, Amamn, To Stent or Not to Stent,
Schweiz. Med. Wochenchr. 1999; 129:1979-96; Tan, Lim, What you Need
to Know-Coronary Stenting-What 's New in the Horizon, Singapore
Med. J. 1999; Vol. 40(06). Treatment of bifurcation lesions is also
common. See, Holmes et al., Coronary Artery Stents, JACC Vol. 32
No. 5, 1998:1471-82. Treatment of bifurcation lesions is associated
with increased early complications including compromise of either
the branch vessel (the vessel off the main or parent vessel) or the
target lesion (usually the lesion in the parent vessel) and
increased potential for restenosis because of inadequate initial
results. Stenting has an additional potential problem in that it
may impair access to the side branch.
[0012] Current practices for improving access to ostial lesions,
elongated lesions, bifurcating lesions and other difficult to treat
stenoses include multiple guide wires. The use of multiple guide
wires can become entangled in the guiding catheter or within the
vessel. Many procedures need to be aborted or delayed if the wires
become hopelessly entangled; some cases are then moved to open
heart surgery due to loss of stents in the coronary vessel or
coronary occlusion from dissection. To maintain side branch access,
"jailing guide wire technique" has been used in the past where the
wire to the side branch artery is pinned between the stent and the
vessel wall. If the jailed wire to the side branch artery is not
needed, the wire is then removed and the stent further dilated. In
addition to jailing the wire, there is also "jailing of the side
branch artery access or origin" by the placement of stent across a
bifurcating stenosis or a stenosis very close to a side branch
artery. However, there is no guide wire in the side branch. But the
opening of the side branch is covered with the stent. The side
branch opening may be compromised by the struts of the stent,
plaque shifting into the side branch or compression. These unwanted
effects may acutely close the side branch manifesting as an acute
myocardial infarction or later as restenosis from neointimal
hyperplasia causing restriction in blood flow or ischemia.
Treatment of the side branch next to the stenosis has been
recognized as technically challenging for interventionalists as
well as to patients. One goal of the current invention is to help
eliminate and avoid these challenges.
[0013] Given the foregoing, a method and apparatus to avoid
entanglement of guide wires, damage to vessels and better access to
branch vessels will be a further advancement in the area of
interventional procedures.
SUMMARY OF THE INVENTION
[0014] The present invention is directed to a method and apparatus
for use in interventional medicine; particularly in multiple branch
lesions located in the coronary and peripheral vasculature. The
invention consists of a sheath containing single or multiple
exitable lumens for the guidance of medical devices used in
interventional medicine. The invention consists of exitable lumen
guide wire sheaths wherein each sheath contains individually
compartmentalized exitable lumens; each walled off from the other
and each containing a mode of exit for the wire. Separation of the
wires during that portion of the procedure prior to deployment of
the stent or inflation of the balloon eliminates the risk of
entanglement of multiple wires. A method for accomplishing this is
introduced using the present invention to separate the wires prior
to deployment and dilation of a balloon and stent or other selected
intra-vascular medical device.
[0015] Each walled off lumen becomes a channel for travel of an
individual guide wire. The first end of the sheath is located at
the proximal portion, that portion that remains within the hands of
the interventionalist or other practitioner. The first end of the
sheath contains a feeder portion of greater durometer than the rest
of the sheath. The feeder portion will have a channel corresponding
to each individually compartmentalized lumen. The feeder portion
will have an exitable portion along its length for the initial
separation of a selected guide wire. The distal part of the
exitable lumen guide wire sheath, that portion introduced
percutaneously to the target lesion, is more flexible than the
first end. In one preferred embodiment, the wall of the lumen can
be opened along its length. In this way, a first selected guide
wire may exit the sheath as a balloon and stent are advanced along
its length or the sheath may be easily removed without losing wire
position. The first selected guide wire is able to completely exit
the individually compartmentalized exitable lumen as the end of the
particular compartment may be selectively closed off at its distal
end. Once the first selected wire and balloon are free of the
sheath, the interventionalist or other practitioner may inflate and
enlarge the stenotic lumen with the stent in a desired location. In
another preferred embodiment, the distal second end of a selected
exitable lumen of the exitable lumen guide wire sheath may be
closed off and be distal to a pre-selected opening for directional
advancement of a guide wire.
[0016] The first selected guide wire, having performed its
function, allows for a second selected guide wire to be used
without the risk of entanglement of the wires. The selected
procedure may continue with additional guide wires without the risk
of entanglement.
[0017] Other embodiments of the invention include differing
fabrications of the wall of the individually compartmentalized
lumens. Preferably, the design is directed to an ease of separation
of the wire from the individually compartmentalized lumen. Scoring,
weakening, fenestrating, and mold rolling the wall of the lumen are
examples of such designs. This may be mounted, attached or fused to
catheter balloon design(s).
BRIEF DESCRIPTION OF THE FIGURES
[0018] FIG. 1 is a diagrammatic representation of an exitable lumen
guide wire sheath showing multiple lumens.
[0019] FIG. 2 is a cross section view of an embodiment of the
invention showing an exit for the guide wires.
[0020] FIG. 3 illustrates a further embodiment of the invention
showing a molded rolling of the flexible sheath.
[0021] FIG. 4 is a cross section view of the embodiment of FIG. 3
showing the individually compartmentalized lumens formed by molded
rolling of the flexible sheath.
[0022] FIG. 5a illustrates a selected length of exitable lumen
guide wire sheath inserted into a partially dilated stent.
[0023] FIG. 5b illustrates a selected length of exitable lumen
guidewire sheath captured via a crimped stent.
[0024] FIG. 6 illustrates a bifurcation lesion example of a
multiple branched lesion with a guide wire advanced in the main
branch.
[0025] FIG. 7 illustrates the back loading of a first guide wire in
to an exitable lumen guide wire sheath.
[0026] FIG. 8 illustrates the advancement of an exitable lumen
guide wire sheath towards a target lesion.
[0027] FIG. 9 illustrates the placement of a first guide wire and a
second guide wire in a multiple branch lesion.
[0028] FIG. 10 illustrates a portion of exitable lumen guide wire
sheath and mode of exit of guide wires through the exitable
lumen.
[0029] FIG. 11 illustrates an example of an intra-vascular medical
device displacing wires from the exitable lumen guide wire
sheath.
[0030] FIG. 12 illustrates placement of a wire in the side branch,
or the desired branch, of a multiple branch lesion.
[0031] FIG. 13 illustrates the back loading an intra-vascular
medical device.
[0032] FIG. 14 illustrates the positioning of an intra-vascular
medical device, here a stent.
[0033] FIG. 15 illustrates the expansion of the stent in the
multiple branch lesion.
[0034] Note that the figures and representations in the figures are
not proportional and are for explanatory purposes only.
DETAILED DESCRIPTION OF THE INVENTION
[0035] The references cited above and below are hereby incorporated
by reference as if fully set forth herein. The present invention
involves a method and apparatus for use in interventional
medicine.
[0036] Referring to FIG. 1 and FIG. 2, the invention contains a
first end 1 that is continuous with the number of individually
compartmentalized lumens 3 in the flexible sheath 4. Individually
compartmentalized lumens 3 are contained in a flexible sheath 4,
each walled off from other individually compartmentalized lumens 3
by a division 5. The flexible sheath 4 is distal to the first end.
The first end section of greater durometer is the feeder portion 6
of the exitable lumen guide wire sheath 7. It is from the feeder
portion 6 of the exitable lumen guide wire sheath that the
interventionalist or other practitioner is able to control the path
and direct the course of the guide wire 8 (here shown as multiple
guide wires 8a, 8b). This feeder portion 6 may be composed of, but
is not limited to, any number of plastics, ceramics, rubber, and
composite materials.
[0037] The first end 1 and feeder portion 6 are connected to a
flexible sheath 4. The flexible sheath 4 is of a lesser durometer
than the feeder portion 6. The flexible sheath 4 may contain a
multiple of lumens 9. Each lumen contains or has an exit 10 for a
guide wire 8 (8a, 8b) that extends from the first end 1 to the
second end 11.
[0038] FIG. 3 represents a further embodiment of the invention.
Here, the individually compartmentalized lumens 103 are separated
by molded rolling of the walls of the exitable lumen guide wire
sheath 107. In this embodiment the first end 101 and feeder portion
106 contain a locking mechanism, for example, a Luer Lock section
100. FIG. 4 shows a cross section of this embodiment wherein the
individually compartmentalized lumens 103 have been molded into a
rolled configuration to provide for the exit 110 of the guide wire
or guide wires in applications. For a bifurcation lesion, the
flexible sheath 104 contains two coils that have been molded and
rolled individually upon themselves to create a lumen 103 for a
guide wire 108 (here shown as multiple guide wires 108a, 108b). A
fold 105 in the middle of the flexible sheath 104 separates the
individualized exitable lumens. The diameter can be approximately
1-2 mm to allow passage into a coronary or small peripheral vessel.
Again, the guide wires, here a first 108a and a second guide wire
108b, will be back loaded into the flexible sheath 104. This could
be accomplished during or before the intervention procedure. The
center fold 105 of the mold rolled flexible sheath 104 separates
the lumens. A first guide wire 108a may then be advanced to and
advanced across target lesion #1 of a bifurcation lesion. The
exitable lumen guide wire sheath 107 can then be advanced to target
lesion #2 and the second guide wire 108b can be placed across
lesion #2. At this stage, as above, the first 108a and second 108b
wires are separate. As the interventionist advances an
intra-vascular medical device toward each lesion, the molded roll
would slightly unwind to accommodate the intra-vascular medical
device, say a balloon catheter, while keeping the wires separate.
The lesions may be treated, i.e., pre-dilated, and made ready for
the bifurcating stents with two balloons. At this stage, both
molded rolls in the flexible sheath 104 will uncoil as the stent
and balloon in each lumen are advanced.
[0039] In other embodiments of the invention the exit 10 may be
created by, but is not limited to, a series of fenestrations; a
weakening in the wall of the flexible sheath that can be severed
with the pressure from the forward advancement of an intra-vascular
medical device along the wire; a folded over lapping section of
flexible sheath; and, a molded rolling of the individually
compartmentalized lumen upon itself that will separate as the
intra-vascular medical device chosen is advanced along the
wire.
[0040] In one embodiment of the invention an exitable lumen guide
wire sheath is used and is combined with a balloon and stent
arrangement 200. In this embodiment, depicted in FIG. 5a, a
selected length of exitable lumen guide wire sheath 207 is inserted
into a partially dilated stent 217 and then the stent 217 is then
crimped (FIG. 5b) to capture the selected length of exitable lumen
guide wire sheath 207. The balloon and stent arrangement 200, now
containing the selected length of exitable lumen guide wire sheath
207, is clipped or otherwise coupled to a catheter shaft 250. The
benefit of this particular embodiment will be addressed more
completely in the examples that follow.
[0041] In one embodiment of the method and apparatus of the
invention, the guide wires are back loaded in the distal second end
11 of the exitable lumen guide wire sheath 7 and out the feeder
portion 6. Back loading refers to introduction of the guide wires 8
(8a, 8b) into the second end 11 of the flexible sheath 4 and
advancing the exitable lumen guide wire sheath 7 toward a
pre-identified lesion. After the guide wires 8 (8a, 8b) are in
place, and the flexible sheath 4 has been introduced to a vessel
through an incision, intra-vascular medical devices, such as a
balloon catheter and stent, rotational cutting devices, laser
apparatus or any number of intra-vascular medical devices used in
vascular procedures can be advanced toward the lesion. The target
lesion may be, but is not limited to, any stenotic vessel or cause
of a stenotic vessel.
[0042] Once the target lesion is reached, a guide wire 8 is
advanced through a selected part of the target lesion. For example,
in a bifurcation lesion as depicted in FIG. 6, the first guide wire
308a may be advanced into the main branch 350 of a multiple branch
lesion.
[0043] A further embodiment of the invention contains a
prefabricated opening 16 at the distal end of the flexible sheath 4
just proximal to the second end. In this embodiment, a selected
lumen or lumens is closed off at the second end 11. This allows
directional advancement of a guide wire into a selected branch of a
multiple branch lesion. Example IV, below, explains a use of this
embodiment.
EXAMPLE I
[0044] Two Guide Wire PCTA Technique without Use of the Present
Invention
[0045] The use of the two-guide wire method known in the art
substantially reduces the risk of damage to a lateral branch,
improves immediate dilatation of the major vessel, yet fails to
affect the number of restenontic lesions in the late period.
Further, problems of entanglement and increased neointimal
hyperplasia are common. See, Abugov SA; Rudenko BA; Puretskii MV;
Saakian Iu M; Sankov OV; Davydov SA; Belov Iu V; Sulimov, A
comparative analysis of the immediate and late results of coronary
balloon angioplasty in bifurcation stenoses performed by the
traditional method and by the "2-guide" method, Vestn. Rentgenol.
Radiol. 1998 Jul-Aug;(4):10-4
[0046] To evaluate the efficiency of Percutaneous Transluminal
Coronary Angioplasty (PTCA) for bifurcation stenoses, which had
been made by the two-guide wire method, the results of
angioplasties were examined in 147 patients with coronary heart
disease. PTCA had been performed routinely in 54 patients and by
the two-guide method in 32. Sixty-one patients who had undergone
angioplasty for nonbifurcation lesions served as a control group.
In the group of routine PTCA procedures, poor results with residual
stenosis of the major vessel were seen in 13% of cases, the
incidence of complications (dissection of unfavorable types,
thrombosis of the major vessel) was 29.6%. In the two-guide wire
PTCA technique, these indices were 15.6 and 2%, respectively, the
incidence of restenosis was 46.9% and that of branch lesions was
6.3%. The high degree of restenosis is consistent with damage to
the side branch vessel upon dilation of the major branch. Further,
complications in two guide wire techniques are consistent with
entanglement of the wires and damage to the intima due to snowplow
effects and crossing and re-crossing of the stents and balloon.
These findings lead to the conclusions that routine angioplasty of
bifurcation stenoses yields poor early and late results of
dilatation of lateral branches. Multi-guide wire techniques have
advantages but are also attended by significant disadvantages.
Routine PTCA and can be further improved using a exitable guide
wire sheaths to avoid complications of entanglement and damage to
the intima.
EXAMPLE II
[0047] Sequential Double Balloon Inflation without Use of the
Present Invention
[0048] Bifurcation stenoses have been recognized to be at "high
risk" for acute closure during Percutaneous Transluminal Coronary
Angioplasty. See, Pinkerton CA; Slack JD Complex coronary
angioplasty: a technique for dilatation of bifurcation stenoses.
Angiology 1985 Aug;36(8):543.
[0049] Use of the traditional single balloon technique in such
situations often results in acute closure or worsening of the
stenosis in the other branch. Again, this is a complication
associated with dilation of a first, usually the parent, branch
which results in a closure of the unprotected lateral branch. A
technique utilizing simultaneous inflation of two balloons,
("kissing balloon" technique) has been utilized to avoid this
complication. The kissing balloon technique uses a balloon advanced
across both the main and side branch lesions. In this way,
inflation of the balloon does not create collateral crushing of the
branch vessel.
[0050] A double balloon technique has been developed using
sequential inflations rather than simultaneous inflations to
preserve the integrity of both branches while avoiding the arterial
trauma produced by inflating two balloons in a small artery
simultaneously. Twelve of 13 bifurcation stenoses were successfully
treated with this sequential inflation double balloon technique.
The initial results suggest high success when using a two-balloon
technique. Greater efficacy and technical ease will be increased
using an exitable lumen guidewire sheath, particularly in the
embodiment using a selected length of exitable lumen guide wire.
Using the technique of the present invention, balloons are located
simultaneously in multiple branches thus avoiding the complications
of closure of the collateral branches. Further, simultaneous
inflation, when desired over sequential inflation, may also be
accomplished.
EXAMPLE III
[0051] Use of Exitable Lumen Guide Wire Sheath in Dilation and
Stenting
[0052] This example will demonstrate use of the exitable lumen
guide wire sheath in the dilation and stenting of a bifurcation
lesion.
[0053] Referring to FIG. 6, a diagrammatic representation of a
bifurcation lesion 12 is shown. In this diagram, the lesion is
distal and proximal to the side branch 360. It is a representation
of a difficult to treat ostial type bifurcation lesion. As noted
above, simple balloon dilation of the main branch 350 may close the
ostium 340 of the side branch 360. Further, in a phenomenon known
to those skilled in the art, the dilation of the parent lesion may
create a "snowplow" effect. The snowplow effect is the unwanted
movement of a plaque upon dilation of a vessel. To avoid these and
other complications of treatment of bifurcation lesions noted
above, an exitable lumen guide wire sheath is used.
[0054] FIG. 6 shows the placement of a first guidewire 8a through
the main vessel 350 and lesion 12. The first guide wire 8a is seen
to have been advanced through the proximal and distal portion of
the lesion. At this time the first guide wire 8a is back loaded on
to the exitable lumen guidewire sheath. Specifically, for this
example, the exitable sheath is a multi-lumen exitable sheath. FIG.
7 illustrates this back loading of a first guidewire 8a on to an
exitable multi-lumen sheath 7.
[0055] At this point the exitable multi-lumen guidewire sheath 7 is
advanced along the first guide wire toward the bifurcation lesion
12. FIG. 8 demonstrates this position. For this type of lesion,
proximal to the exitable multi-lumen guidewire sheath's second end
11 is a prefabricated opening 16 for directional advancement of a
second guidewire 8b. FIG. 8 illustrates the placement of the first
guide wire 8a and the second guide wire 8b. The interventionalist
or other practitioner has the ability to steer the guide wires from
the feeder portion 6 of the exitable multi-lumen guidewire sheath
7. As the second guide wire 8b is advanced to the distal end of the
exitable multi lumen sheath 7, the guide wire is steered in to a
prefabricated opening which has been carefully positioned at the
ostium 340 of the side branch lesion. The second guide wire 8b is
then advanced through the ostium 340 of the side branch vessel
360.
[0056] Another important advantage of the current invention, is
that the multiple guide wires 8a, 8b are completely separate and
are not entangled. FIG. 10 shows a portion of an exitable
multi-lumen sheath 7. Further, FIG. 10 depicts the exitable
property of the sheath. In this embodiment, the exitable property
is achieved via a longitudinal slit 10.
[0057] At this point in the treatment of the bifurcation lesion the
interventionalist or other practitioner manipulates either the
first or second or both guide wires out of the exit provided in the
feeder portion 6. An intra-vascular medical device, in this example
a balloon catheter and stents, is back loaded at the proximal end
of the guide wires. As is seen in FIG. 11, as the balloon 18 and
stent 17 are advanced along the exitable multi-lumen guidewire
sheath 7, the guide wires exit the sheath via the exitable portion
10. Further, a prefabricated opening 16 in an exitable lumen guide
wire sheath may be employed for directional advancement of the
guide wire. As mentioned, the opening 16 is just proximal to a
selectively closed off second end of a selected exitable lumen
guide wire sheath.
EXAMPLE IV
[0058] Protecting Access to the Side Branch in a Bifurcation Lesion
using Exitable Lumen Guide Wire Sheath
[0059] The treatment of bifurcation lesions commonly causes closure
of a side branch due to caging of the stent which makes it nearly
impossible to enter the side branch lesion. This example describes
the use of the method and apparatus of the present invention to
protect access to the side branch, or a desired branch in a
multiple branch lesion. In so doing, the embodiment depicted in
FIGS. 5a and 5b will be beneficial.
[0060] It is advantageous to include a radio-opaque distal marker
to the selected length of the exitable lumen guide wire sheath or
of the balloon. For example, a very short marker would be placed
longitudinally near the tip.
[0061] Again, an additional goal of an intervention procedure on a
multi-branch lesion is to protect the side branch for access since
an additional stent may cross it. As mentioned, current practice in
cardiology has risks of caging the vessel so that wire access in
the side branch may become impossible.
[0062] To decrease the risk, an exitable lumen guide wire sheath
with, for example, a side slit, can be easily used to protect the
side branch. These can be premounted by a manufacturer of the stent
or placed by an interventionalist or other practitioner. It is,
however, critical to pre-measure the amount of exitable lumen
guidewire sheath to be used. This is also done, as is immediately
apparent to those skilled in the art, by proper pre-identification
and study of the target lesion; it is dependent on the placement of
the lesion and its relation to the branch(s) as well as the
branch(s) relation and angulation to the main vessel.
[0063] Referring to FIG. 12, the safest method is to place wires in
the main vessel and the side branch that one seeks to protect. (If
there were two branches, then three wires would have to be used
along with the exitable multi-lumen sheath proposed.) The
interventionalist or other practitioner can then predilate the
lesions with balloons with the wires in place. Previously, the wire
in the side branch 208b had to be removed prior to placing the
stent so the wire would not be jailed or trapped behind the stent.
In this method, the stent will be dilated partially, the exitable
lumen guide wire sheath (here with a slit for the guide wire exit)
will be placed through the stent (as mentioned, the length can be
determined by the interventionalist, other practitioner or
premanufactured).
[0064] The wires 208a, 208b are then back loaded into the lumens of
the sheath and balloon as in FIG. 13. In the case where an
embodiment of the invention containing a prefabricated opening 16
is used, only the first guide wire 8a is back loaded. The stent,
balloon and the mounted sheaths 200 are advanced to the
bifurcation. The stent 217 is positioned as depicted in FIG. 14. At
this point there is still complete separation of the wires. The
balloon 218 is inflated, expanding the stent 217 in to the wall of
the vessel as in FIG. 15. The prefabricated opening 16, if this
embodiment is used, is carefully placed by the interventionalist or
other practitioner over the ostium of the branch to be treated.
[0065] At this point, any medical device needed may be advanced
down the second guide wire 208b and the medical device will be
directed passed or through the expanded stent 218. (Or the
prefabricated opening if that embodiment is chosen.) As the medical
device, say an additional stent, is advanced to meet the exitable
lumen guide wire sheath it will pull the guide wire 208b away from
the exitable lumen guide wire sheath while remaining separate from
other wires. As described above and as depicted in FIG. 15, the
wire will advance through the prefabricated opening. Throughout the
method, safe and protected access to the side branch or desired
branch is achieved.
[0066] The preceding examples demonstrate the apparatus and method
of use for an exitable lumen guide wire sheath as well as
suggesting alternate uses. Further, specific examples of
comparisons with traditional treatments and studies are provided.
These are only examples and are not intended to limit the invention
to these examples. It is understood that modifying the examples
above does not depart from the spirit of the invention. It is
further understood that the examples can be applied on their own or
in combination with each other.
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