U.S. patent number RE43,300 [Application Number 10/126,295] was granted by the patent office on 2012-04-03 for apparatus having stabilization members for percutaneously performing surgery and methods of use.
This patent grant is currently assigned to Abbott Cardiovascular Systems Inc.. Invention is credited to John H. Ream, Vahid Saadat.
United States Patent |
RE43,300 |
Saadat , et al. |
April 3, 2012 |
Apparatus having stabilization members for percutaneously
performing surgery and methods of use
Abstract
Apparatus and methods for performing surgery within an organ or
vessel are provided. A catheter is provided having a longitudinal
axis and an end region carrying an end effector, the end region
movable to a series of positions along the longitudinal axis and
with an selectable orientation relative to the longitudinal axis.
The catheter includes elements for stabilizing the end region of
the apparatus within an organ or vessel, and for counteracting
reaction forces developed during actuation of the end effector.
Inventors: |
Saadat; Vahid (Saratoga,
CA), Ream; John H. (San Jose, CA) |
Assignee: |
Abbott Cardiovascular Systems
Inc. (Santa Clara, CA)
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Family
ID: |
45877520 |
Appl.
No.: |
10/126,295 |
Filed: |
April 18, 2002 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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08863877 |
May 27, 1997 |
5910150 |
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60032196 |
Dec 2, 1996 |
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Reissue of: |
09213089 |
Dec 15, 1998 |
6051008 |
Apr 18, 2000 |
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Current U.S.
Class: |
606/159; 606/7;
606/170; 606/15; 607/122 |
Current CPC
Class: |
A61B
18/00 (20130101); A61B 17/320758 (20130101); A61B
18/1492 (20130101); A61B 17/3207 (20130101); A61B
2017/00026 (20130101); A61B 2018/1861 (20130101); A61B
2090/034 (20160201); A61M 25/0084 (20130101); A61B
2018/00839 (20130101); A61B 2218/002 (20130101); A61B
2017/00398 (20130101); A61B 2018/00738 (20130101); A61B
2090/0811 (20160201); A61B 2017/00247 (20130101); A61B
2017/22077 (20130101); A61B 2017/3488 (20130101); A61B
2017/306 (20130101); A61B 2017/00991 (20130101); A61B
2018/00291 (20130101); A61B 2090/3782 (20160201); A61B
2018/00279 (20130101); A61B 2218/007 (20130101); A61B
2018/1437 (20130101); A61B 2018/00196 (20130101); A61B
2018/00208 (20130101); A61B 2018/1435 (20130101); A61B
2018/00916 (20130101); A61B 2017/00685 (20130101); A61B
34/20 (20160201); A61B 2017/00022 (20130101); A61B
2017/00039 (20130101); A61B 2017/003 (20130101); A61B
2217/005 (20130101); A61B 90/37 (20160201); A61B
2018/00392 (20130101); A61B 2018/00761 (20130101); A61B
2018/00267 (20130101) |
Current International
Class: |
A61B
17/22 (20060101) |
Field of
Search: |
;606/1,108,167,170,171,180,185,2,159,7,15,181 |
References Cited
[Referenced By]
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0807412 |
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0868 923 |
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|
Primary Examiner: Nguyen; Tuan
Attorney, Agent or Firm: Blakely, Sokoloff, Taylor &
Zafman LLP
Parent Case Text
REFERENCE TO RELATED APPLICATIONS
The present application is a continuation-in-part application of
commonly assigned U.S. patent application Ser. No. 08/863,877,
filed May 27, 1997, now U.S. Pat. No. 5,910,150 .Iadd.which claims
the benefit of the filing date of U.S. provisional patent
application Ser. No. 60/032,196, filed Dec. 2, 1996.Iaddend..
Claims
What is claimed is:
.[.1. Apparatus for treating an organ or vessel defining a cavity,
the apparatus comprising: a catheter shaft adapted for insertion
into the cavity, the catheter shaft having a distal region and a
portion defining a groove, a guide member including an end effector
to treat an interior wall of the hollow-body organ, the guide
member disposed in the groove for translation along the catheter
shaft; means for disposing the end effector at a selected
orientation relative to the catheter shaft; and a stabilization
assembly, disposed in the distal region, that stabilizes the
catheter shaft and guide member within the organ or vessel during
actuation of the end effector..].
2. .[.The apparatus as defined in claim 1 wherein the stabilization
assembly comprises a band movable from a first position, wherein
the band is disposed adjacent to an exterior surface of the
catheter shaft, to a second position, wherein the band forms a
plurality of loops extending from the exterior surface of the
catheter shaft..]. .Iadd.Apparatus for treating an organ or vessel
defining a cavity, the apparatus comprising: a catheter shaft
adapted for insertion into the cavity, the catheter shaft having a
distal region and a portion defining a groove, a guide member
carrying an end effector formed separately from the guide member to
treat an interior wall of the organ or vessel, the guide member
slidably engaged in the groove for selective translation along a
longitudinal axis of the catheter shaft; means for disposing the
end effector at a selected orientation relative to the longitudinal
axis of the catheter shaft; and a stabilization assembly, formed
separately from the catheter shaft and disposed in the distal
region of the catheter shaft, that stabilizes the catheter shaft
when activated within the organ or vessel during actuation of the
end effector, wherein while the stabilization assembly is
activated, the end effector is capable of making a plurality of
treatment sites which are orthogonally disposed relative to a
portion of the distal region of the catheter shaft, and which are
placed longitudinally relative to the distal region of the catheter
shaft, through translation of the guide member without
repositioning at least a portion of the catheter shaft within the
organ or vessel, wherein the stabilization assembly comprises a
band movable from a first position, wherein the band is disposed
adjacent to an exterior surface of the catheter shaft, to a second
position, wherein the band forms a plurality of loops extending
from the exterior surface of the catheter shaft..Iaddend.
3. .[.The apparatus as defined in claim 1.]. .Iadd.Apparatus for
treating an organ or vessel defining a cavity, the apparatus
comprising: a catheter shaft adapted for insertion into the cavity,
the catheter shaft having a distal region and a portion defining a
groove, a guide member carrying an end effector formed separately
from the guide member to treat an interior wall of the organ or
vessel, the guide member slidably engaged in the groove for
selective translation along a longitudinal axis of the catheter
shaft; means for disposing the end effector at a selected
orientation relative to the longitudinal axis of the catheter
shaft; and a stabilization assembly, formed separately from the
catheter shaft and disposed in the distal region of the catheter
shaft, that stabilizes the catheter shaft when activated within the
organ or vessel during actuation of the end effector, and wherein
while the stabilization assembly is activated the end effector is
capable of making a plurality of treatment sites which are
orthogonally disposed relative to a portion of the distal region of
the catheter shaft, and which are placed longitudinally relative to
the distal region of the catheter shaft, through translation of the
guide member without repositioning at least a portion of the
catheter shaft within the organ or vessel, .Iaddend.wherein the end
effector comprises a rotating cutting head.
4. The apparatus as defined in claim 3 wherein the end effector
further comprises an electrode adapted to deliver RF energy.
5. .[.The apparatus as defined in claim 1.]. .Iadd.Apparatus for
treating an organ or vessel defining a cavity, the apparatus
comprising: a catheter shaft adapted for insertion into the cavity,
the catheter shaft having a distal region and a portion defining a
groove, a guide member including an end effector to treat an
interior wall of the organ or vessel, the guide member slidably
engaged in the groove for selective translation along a
longitudinal axis of the catheter shaft; means for disposing the
end effector at a selected orientation relative to the longitudinal
axis of the catheter shaft; and a stabilization assembly, formed
separately from the catheter shaft and disposed in the distal
region of the catheter shaft, that stabilizes the catheter shaft
when activated within the organ or vessel during actuation of the
end effector, and wherein while the stabilization assembly is
activated the end effector is capable of making a plurality of
treatment sites which are orthogonally disposed relative to a
portion of the distal region of the catheter shaft, and which are
placed longitudinally relative to the distal region of the catheter
shaft, through translation of the guide member and without
repositioning at least a portion of the catheter shaft within the
organ or vessel, .Iaddend.wherein the apparatus further comprises
an outer sheath and the stabilization assembly comprises a
plurality of wire hoops affixed to the catheter shaft, the
plurality of wire hoops movable from a first position wherein the
wire hoops are confined within the outer sheath, and a second
position, wherein the wire hoops project outwardly from the
catheter shaft to engage an interior surface of the organ or
vessel.
6. The apparatus as defined in claim 5 wherein the end effector
comprises a rotating cutting head.
7. The apparatus as defined in claim 6 wherein the end effector
further comprises an electrode adapted to deliver RF energy.
8. Apparatus for treating an organ or vessel comprising: an outer
sheath; a guide member extending from the outer sheath, the guide
member .[.including.]. .Iadd.carrying .Iaddend.an end effector
.Iadd.formed separately from the guide member .Iaddend.for treating
an interior region of .[.an.]. .Iadd.the .Iaddend.organ or vessel,
an end region of the guide catheter movable to dispose the end
effector at a selected orientation .Iadd.and position
.Iaddend.relative to .[.the.]. .Iadd.a longitudinal axis of a
.Iaddend.catheter shaft; and a stabilization assembly.Iadd., which
is formed separately from the outer sheath, .Iaddend.comprising a
plurality of bands extending from within the outer sheath, each one
of the plurality of bands terminating in a spool that
.[.contacts.]. .Iadd.is adapted to be in contact with .Iaddend.an
interior wall of the organ or vessel, the stabilization assembly
stabilizing the guide member during actuation of the end
effector.
9. The apparatus as defined in claim 8 wherein the end effector
further comprises an electrode adapted to deliver RF energy to the
treatment site.
.[.10. Apparatus for performing transmyocardial revascularization,
the apparatus comprising: a catheter shaft adapted for insertion
into a patient's left ventricle, the catheter shaft having a distal
region including a portion adapted to engage an interior wall in a
vicinity of an apex of the patient's left ventricle; a guide member
having an end effector to treat the interior wall of the left
ventricle, the guide member disposed for translation along the
catheter shaft; and a stabilization assembly, disposed in the
distal region, that stabilizes the catheter shaft and guide member
within the left ventricle during actuation of the end
effector..].
11. .[.The apparatus as defined in claim 10.]. .Iadd.Apparatus for
performing transmyocardial revascularization, the apparatus
comprising: a catheter shaft adapted for insertion into a patient's
left ventricle, the catheter shaft having a distal region including
a portion adapted to engage an interior wall in a vicinity of an
apex of the patient's left ventricle; a guide member carrying an
end effector formed separately from the guide member to treat the
interior wall of the left ventricle, the guide member disposed for
selective translation along a longitudinal axis of the catheter
shaft; and a stabilization assembly, formed separately from the
catheter shaft and disposed in the distal region of the catheter
shaft, to alternate between a retracted position and an expanded
position, that stabilizes the catheter shaft within the left
ventricle during actuation of the end effector, .Iaddend.wherein
the stabilization assembly comprises a band movable from a first
position, wherein the band is disposed adjacent to an exterior
surface of the catheter shaft, to a second position, wherein the
band forms a plurality of loops extending from the exterior surface
of the catheter shaft.
12. .[.The apparatus as defined in claim 10.]. .Iadd.Apparatus for
performing transmyocardial revascularization, the apparatus
comprising: a catheter shaft adapted for insertion into a patient's
left ventricle, the catheter shaft having a distal region including
a portion adapted to engage an interior wall in a vicinity of an
apex of the patient's left ventricle; a guide member carrying an
end effector formed separately from the guide member to treat the
interior wall of the left ventricle, the guide member disposed for
selective translation along a longitudinal axis of the catheter
shaft; and a stabilization assembly, formed separately from the
catheter shaft and disposed in the distal region of the catheter
shaft, to alternate between a retracted position and an expanded
position, that stabilizes the catheter shaft within the left
ventricle during actuation of the end effector, .Iaddend.wherein
the stabilization assembly comprises a wire movable from a first
position, wherein the wire is partially retracted within a lumen of
the catheter shaft, to a second position, wherein the wire forms a
plurality of .Iadd.sinusoidal .Iaddend.bends that contact and
support the catheter shaft.
13. .[.The apparatus as defined in claim 10.]. .Iadd.Apparatus for
performing transmyocardial revascularization, the apparatus
comprising: a catheter shaft adapted for insertion into a patient's
left ventricle, the catheter shaft having a distal region including
a portion adapted to engage an interior wall in a vicinity of an
apex of the patient's left ventricle; a guide member carrying an
end effector formed separately from the guide member, wherein a
distal portion of the end effector is configured for selective
bending at an angle relative to a main body of the guide member to
treat the interior wall of the left ventricle, the guide member
disposed for selective translation along a longitudinal axis of the
catheter shaft; and a stabilization assembly, formed separately
from the catheter shaft and disposed in the distal region of the
catheter shaft to alternate between a retracted position and an
expanded position, that stabilizes the catheter shaft within the
left ventricle during actuation of the end effector, and wherein
while the stabilization assembly is expanded the end effector is
capable of making a plurality of treatment sites which are
orthogonally disposed relative to a portion of the distal region of
the catheter shaft, and which are placed longitudinally relative to
the distal region of the catheter shaft, through translation of the
guide member without repositioning at least a portion of the
catheter shaft within the left ventricle, .Iaddend.wherein the end
effector comprises a rotating cutting head.
14. The apparatus as defined in claim 12 wherein the end effector
further comprises an electrode adapted to deliver RF energy.
.[.15. A method of treating an interior region of an organ or
vessel comprising: providing apparatus having a catheter shaft
adapted for insertion into an organ or vessel, a guide member
mounted in a groove on the catheter shaft and having an end
effector for treating an interior region of the organ or vessel,
and a stabilization assembly mounted on the catheter shaft;
inserting the apparatus within an organ or vessel; deploying the
stabilization assembly to stabilize the catheter shaft and guide
member within the organ or vessel; translating the guide member
within the groove of the catheter shaft to dispose the end effector
at a selected location relative to the catheter shaft; and
actuating the end effector to form a channel in an interior region
of the organ or vessel..].
16. .[.The method as defined in claim 15 further comprising.].
.Iadd.A method of treating an interior region of an organ or vessel
comprising: providing an apparatus having a catheter shaft adapted
for insertion into the organ or vessel, a guide member slidably
mounted in a groove on the catheter shaft and carrying an end
effector formed separately from the guide member for treating an
interior region of the organ or vessel, and a stabilization
assembly mounted on the catheter shaft and formed separately from
the catheter shaft; inserting the apparatus within the organ or
vessel; deploying the stabilization assembly to stabilize the
catheter shaft within the organ or vessel; slidably translating the
guide member within the groove of the catheter shaft to dispose the
end effector at a selected position relative to a longitudinal axis
of the catheter shaft; actuating the end effector to form a channel
in an interior region of the organ or vessel; and .Iaddend.
delivering RF energy to the channel to create a controlled depth of
necrosis.
.[.17. The method as defined in claim 15 further comprising,
following actuating the end effector: translating the guide member
in the groove relative to the catheter shaft to relocate the end
effector; and repeating actuation of the end effector..].
18. .[.The method as defined in claim 15.]. .Iadd.A method of
treating an interior region of an organ or vessel comprising:
providing an apparatus having a catheter shaft adapted for
insertion into the organ or vessel, a guide member slidably mounted
in a groove on the catheter shaft and carrying an end effector
formed separately from the guide member for treating an interior
region of the organ or vessel, and a stabilization assembly formed
separately from the catheter shaft and mounted on the catheter
shaft, .Iaddend.wherein the stabilization assembly comprises a band
movable from a first position, wherein the band is disposed
adjacent to an exterior surface of the catheter shaft, to a second
position, wherein the band forms a plurality of loops extending
from the exterior surface of the catheter shaft, and deploying the
stabilization assembly to stabilize the catheter shaft .[.and guide
member.]. within the organ or vessel .[.further comprises moving
the band from the first position to the second position.]. .Iadd.;
inserting the apparatus within the organ or vessel; deploying the
stabilization assembly to stabilize the catheter shaft within the
organ or vessel, wherein deploying the stabilization assembly
comprises moving the band from the first position to the second
position; slidably translating the guide member within the groove
of the catheter shaft to dispose the end effector at a selected
position relative to a longitudinal axis of the catheter shaft;
actuating the end effector to form a channel in an interior region
of the organ or vessel.Iaddend..
19. .[.The method as defined in claim 15.]. .Iadd.A method of
treating an interior region of an organ or vessel comprising:
providing an apparatus having a catheter shaft adapted for
insertion into the organ or vessel, a guide member slidably mounted
in a groove on the catheter shaft and carrying an end effector
formed separately from the guide member for treating an interior
region of the organ or vessel, and a stabilization assembly mounted
on the catheter shaft and formed separately from the catheter
shaft; inserting the apparatus within the organ or vessel;
deploying the stabilization assembly to stabilize the catheter
shaft within the organ or vessel; slidably translating the guide
member within the groove of the catheter shaft to dispose the end
effector at a selected position relative to a longitudinal axis of
the catheter shaft; and actuating the end effector to form a
channel in an interior region of the organ or vessel,
.Iaddend.wherein actuating the end effector comprises rotating a
cutting head.
20. .[.The method as defined in claim 15.]. .Iadd.A method of
treating an interior region of an organ or vessel comprising:
providing an apparatus having a catheter shaft adapted for
insertion into the organ or vessel, a guide member slidably mounted
in a groove on the catheter shaft and carrying an end effector
formed separately from the guide member for treating an interior
region of the organ or vessel, and a stabilization assembly, formed
separately from the catheter shaft and mounted on the catheter
shaft, .Iaddend.wherein the stabilization assembly comprises a
plurality of wire hoops affixed to the catheter shaft, the
plurality of wire hoops movable from a first position wherein the
wire hoops are confined within the outer sheath, and a second
position, wherein the wire hoops project outwardly from the
catheter shaft to engage an interior surface of the organ or
vessel, and deploying the stabilization assembly to stabilize the
catheter shaft .[.and guide member.]. within the organ or vessel
further comprises retracting the outer sheath.Iadd.; inserting the
apparatus within the organ or vessel; deploying the stabilization
assembly to stabilize the catheter shaft within the organ or
vessel; slidably translating the guide member within the groove of
the catheter shaft to dispose the end effector at a selected
position relative to a longitudinal axis of the catheter shaft; and
actuating the end effector to form a channel in an interior region
of the organ or vessel.Iaddend..
21. .[.The method as defined in claim 15.]. .Iadd.A method of
treating an interior region of an organ or vessel comprising:
providing an apparatus having a catheter shaft adapted for
insertion into the organ or vessel, a guide member slidably mounted
in a groove on the catheter shaft and carrying an end effector
formed separately from the guide member for treating an interior
region of the organ or vessel, and a stabilization assembly, formed
separately from the catheter shaft and mounted on the catheter
shaft, .Iaddend.wherein the stabilization assembly comprises a wire
movable from a first position wherein the wire is partially
retracted within the catheter shaft, and a second position, wherein
the wire forms a plurality of interconnected bends that engage an
interior surface of the organ or vessel, and deploying the
stabilization assembly to stabilize the catheter shaft .[.and guide
member.]. within the organ or vessel.Iadd., and the method
.Iaddend.further comprises extending the wire so that it resumes a
preformed shape.Iadd.; inserting the apparatus within the organ or
vessel; deploying the stabilization assembly to stabilize the
catheter shaft within the organ or vessel; slidably translating the
guide member within the groove of the catheter shaft to dispose the
end effector at a selected position relative to a longitudinal axis
of the catheter shaft; actuating the end effector to form a channel
in an interior region of the organ or vessel.Iaddend..
22. A method of treating an interior region of an organ or vessel
comprising: providing .Iadd.an .Iaddend.apparatus having an outer
sheath, a guide member extending from the outer sheath, the guide
member .[.including.]. .Iadd.carrying .Iaddend.an end effector
.Iadd.formed separately from the guide member .Iaddend.for treating
an interior region of .[.the.]. .Iadd.an .Iaddend.organ or vessel;
and a stabilization assembly.Iadd., which is formed separately from
the outer sheath, .Iaddend.comprising a plurality of bands
extendable from within the outer sheath, each one of the plurality
of bands terminating in a spool that contacts an interior wall of
the organ or vessel when extended; inserting the apparatus within
an organ or vessel; extending the plurality of bands from the outer
sheath to form spools, each spool contacting an interior wall of
the organ or vessel to stabilize the guide member within the organ
or vessel; translating the guide member to dispose the end effector
at a selected .[.location.]. .Iadd.position relative to a
longitudinal axis of the apparatus.Iaddend.; and actuating the end
effector to form a channel in an interior region of the organ or
vessel.
.Iadd.23. An apparatus for performing transmyocardial
revascularization, the apparatus comprising: a catheter shaft
adapted for insertion into a patient's left ventricle; a guide
member carrying an end effector formed separately from the catheter
shaft to treat an interior wall of the left ventricle, the end
effector disposed for selective translation relative to a
longitudinal axis of the catheter shaft; and a stabilization
assembly, formed separately from the catheter shaft and disposed in
a distal region of the catheter shaft to alternate between a
retracted position and an expanded position, that stabilizes the
catheter shaft within the left ventricle during actuation of the
end effector, wherein the stabilization assembly comprises a band
movable from a first position, wherein the band is disposed
adjacent to an exterior surface of the catheter shaft, to a second
position, wherein the band forms a plurality of loops extending
from the exterior surface of the catheter shaft..Iaddend.
.Iadd.24. An apparatus for performing transmyocardial
revascularization, the apparatus comprising: a catheter shaft
adapted for insertion into a patient's left ventricle; a guide
member carrying an end effector formed separately from the catheter
shaft to treat an interior wall of the left ventricle, the end
effector disposed for selective translation relative to a
longitudinal axis of the catheter shaft; and a stabilization
assembly, formed separately from the catheter shaft and disposed in
a distal region of the catheter shaft, to alternate between a
retracted position and an expanded position, that stabilizes the
catheter shaft within the left ventricle during actuation of the
end effector, wherein the stabilization assembly comprises a wire
movable from a first position, wherein the wire is partially
retracted within a lumen of the catheter shaft, to a second
position, wherein the wire forms a plurality of sinusoidal bends
that contact and support the catheter shaft..Iaddend.
.Iadd.25. An apparatus for improving ischemic cardiac tissue, the
apparatus comprising: a catheter shaft adapted for insertion into a
patient's left ventricle; a member carrying an end effector formed
separately from the catheter shaft, wherein the end effector
comprises a needle, to treat an interior wall of the left
ventricle, the end effector disposed for selective translation
relative to a longitudinal axis of the catheter shaft; and a
stabilization assembly, formed separately from the catheter shaft
and disposed in a distal region of the catheter shaft, to alternate
between a retracted position and an expanded position, that
stabilizes the catheter shaft and member within the left ventricle
during actuation of the end effector, wherein the stabilization
assembly comprises a band movable from a first position, wherein
the band is disposed adjacent to an exterior surface of the
catheter shaft, to a second position, wherein the band forms a
plurality of loops extending from the exterior surface of the
catheter shaft..Iaddend.
.Iadd.26. An apparatus for improving ischemic cardiac tissue, the
apparatus comprising: a catheter shaft adapted for insertion into a
patient's left ventricle; a member carrying an end effector formed
separately from the catheter shaft, wherein the end effector
comprises a needle, to treat an interior wall of the left
ventricle, the end effector disposed for selective translation
relative to a longitudinal axis of the catheter shaft; and a
stabilization assembly, formed separately from the catheter shaft
and disposed in a distal region of the catheter shaft, to alternate
between a retracted position and an expanded position, that
stabilizes the catheter shaft and member within the left ventricle
during actuation of the end effector, wherein the stabilization
assembly comprises a wire movable from a first position, wherein
the wire is partially retracted within a lumen of the catheter
shaft, to a second position, wherein the wire forms a plurality of
sinusoidal bends that contact and support the catheter
shaft..Iaddend.
.Iadd.27. An apparatus for improving ischemic cardiac tissue, the
apparatus comprising: a catheter shaft adapted for insertion into a
patient's left ventricle; a member carrying an end effector formed
separately from the catheter shaft, wherein the end effector
comprises a needle, to treat an interior wall of the left
ventricle, the end effector disposed for selective translation
relative to a longitudinal axis of the catheter shaft; and a
stabilization assembly, formed separately from the catheter shaft
and disposed in a distal region of the catheter shaft, to alternate
between a retracted position and an expanded position, that
stabilizes the catheter shaft and member within the left ventricle
during actuation of the end effector, wherein while the
stabilization assembly is expanded, the end effector is capable of
making a plurality of treatment sites through transition of the
member without repositioning at least a portion of the catheter
shaft within the left ventricle, wherein the stabilization assembly
comprises at least one inflatable hoop member..Iaddend.
Description
FIELD OF THE INVENTION
The present invention relates to apparatus and methods for
performing surgery on an interior wall of a hollow-body organ such
as the heart, or within the brain cavities and the like. More
particularly, the present invention provides a device that enables
a clinician to perform surgery on an interior wall of an organ or
vessel using apparatus for stabilizing an end effector during the
surgery.
BACKGROUND OF THE INVENTION
A leading cause of death in the United States today is coronary
artery disease, in which atherosclerotic plaque causes blockages in
the coronary arteries, resulting in ischemia of the heart (i.e.,
inadequate blood flow to the myocardium). The disease manifests
itself as chest pain or angina. In 1996, approximately 7 million
people suffered from angina in the United States.
Coronary artery bypass grafting (CABG), in which the patient's
chest is surgically opened and an obstructed artery replaced with a
native artery harvested elsewhere, has been the conventional
treatment for coronary artery disease for the last thirty years.
Such surgery creates significant trauma to the patient, requires
long recuperation times, and causes a great deal of morbidity and
mortality. In addition, experience has shown that the graft becomes
obstructed with time, requiring further surgery.
More recently, catheter-based therapies such as percutaneous
transluminal coronary angioplasty (PTCA) and atherectomy have been
developed. In PTCA, a mechanical dilatation device is disposed
across an obstruction in the patient's artery and then dilated to
compress the plaque lining the artery to restore patency to the
vessel. Atherectomy involves using an end effector, such as a
mechanical cutting device (or laser) to cut (or ablate) a passage
through the blockage. Such methods have drawbacks, however, ranging
from re-blockage of dilated vessels with angioplasty to
catastrophic rupture or dissection of the vessel during
atherectomy. Moreover, these methods may only be used for that
fraction of the patient population where the blockages are few and
are easily accessible. Neither technique is suitable for the
treatment of diffuse atherosclerosis.
A more recent technique, which holds promise of treating a larger
percentage of the patient population, including those patients
suffering from diffuse atherosclerosis, is referred to as
transmyocardial revascularization (TMR). In this method, a series
of channels are formed in the left ventricular wall of the heart.
Typically, between 15 and 30 channels about 1 mm in diameter and up
to 3.0 cm deep are formed with a laser in the wall of the left
ventricle to perfuse the heart muscle with blood coming directly
from the inside of the left ventricle, rather than traveling
through the coronary arteries. Apparatus and methods have been
proposed to create those channels both percutaneously and
intraoperatively (i.e., with the chest opened).
U.S. Pat. No. 5,389,096 to Aita et al. describes a catheter-based
laser apparatus for percutaneously forming channels extending from
the endocardium into the myocardium. U.S. Pat. No. 5,380,316 to
Aita et al. describes an intraoperative laser-based system for
performing TMR. U.S. Pat. No. 5,591,159 to Taheri describes a
mechanical apparatus for performing TMR involving a catheter having
an end effector formed from a plurality of spring-loaded
needles.
Neither the Aita nor Taheri devices describe apparatus wherein the
laser-tip or spring-loaded needles are stabilized during the
channel-forming process. Because the end effector of such devices
may shift position while in use, such previously known devices may
not provide the ability to reliably determine the depth of the
channels, nor the relative positions between channels if multiple
channels are formed.
In view of the shortcomings of previously known TMR devices, it
would be desirable to provide apparatus and methods for performing
percutaneous surgery, such as TMR, that permit precise control of
the end region of the device carrying the end effector.
It also would be desirable to control the location of the end
region of the device within the ventricle both with respect to
features of the ventricular walls and in relation to other channels
formed by the device, and to stabilize the end region of the device
within the organ, for example, to counteract reaction forces
created by the actuation of the end effector during treatment.
A number of devices are known in the medical arts that provide
certain aspects of the desired functionality. For example, U.S.
Pat. Nos. 5,389,073 and 5,330,466 to Imran describe steerable
catheters; U.S. Pat. No. 5,415,166 to Imran describes a device for
endocardial mapping; U.S. Pat. No. 4,813,930 to Elliott describes a
radially extendable member for stabilizing an angioplasty catheter
within a vessel; U.S. Pat. No. 5,354,310 describes an expandable
wire mesh and graft for stabilizing an aneurysm; and U.S. Pat. Nos.
5,358,472 and 5,358,485 to Vance et al. describe atherectomy
cutters that provide for aspiration of severed material.
None of the foregoing references overcomes problems associated with
locating an end region of a catheter against a position on the
inside wall of a heart chamber. Moreover, the prior art is devoid
of a comprehensive solution to the above-noted shortcomings of
previously-known apparatus for percutaneously performing surgery,
and especially for performing TMR.
SUMMARY OF THE INVENTION
In view of the foregoing, it is an object of this invention to
provide apparatus and methods for performing surgery, such as TMR,
that permit precise control of an end effector disposed in an end
region of the apparatus.
It is another object of this invention to provide apparatus and
methods, suitable for use in performing TMR and surgery of other
hollow-body organs, that include the capability to stabilize within
the organ an end region of the device carrying an end effector, for
example, to counteract reaction forces created by the end effector
during treatment.
These and other objects of the present invention are accomplished
by providing apparatus having a directable end region carrying an
end effector for performing surgery. Apparatus constructed in
accordance with the present invention comprises a catheter having a
longitudinal axis and an end region movable to a series of
positions along the longitudinal axis. The end region may be
selectively moved to a position at an angle relative to the
longitudinal axis of the catheter, including a substantially
orthogonal position. The catheter includes means for stabilizing a
distal region of the apparatus within a hollow-body organ, and for
counter-acting reaction forces developed during actuation of an end
effector.
In a preferred embodiment of the apparatus of the invention, the
catheter includes a catheter shaft and a guide member disposed for
longitudinal sliding movement within a groove of the catheter
shaft. The guide member includes an end region including an end
effector maneuverable between a transit position wherein the end
region lies parallel to a longitudinal axis of the catheter to a
working position wherein the end region and end effector are
oriented at an angle relative to the longitudinal axis, including a
substantially orthogonal position. The catheter shaft preferably
may include adjustable outwardly projecting stabilization members
to provide a stable platform to counteract reaction forces
generated when the end effector contacts the wall of the
hollow-body organ.
Methods of using the apparatus of the present invention to perform
surgery, such as transmyocardial revascularization, are also
provided.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features of the invention, its nature and various
advantages will be more apparent from the accompanying drawings and
the following detailed description of the preferred embodiments, in
which:
FIG. 1 is a view of a first illustrative embodiment of apparatus
constructed in accordance with the present invention;
FIG. 2 is a perspective view of the distal region and end effector
of the apparatus of FIG. 1;
FIGS. 3A and 3B are, respectively, a perspective view and side view
of stabilization members disposed on the distal region of the
apparatus of FIG. 1;
FIG. 4 is sectional view of an illustrative end effector
constructed in accordance with the present invention;
FIGS. 5A and 5B are, respectively, side and perspective views of an
illustrative handle assembly for controlling and actuating the
apparatus of the present invention;
FIGS. 6A-6C are views showing deployment of the apparatus of FIG. 1
in a patient's left ventricle to perform TMR;
FIG. 7 is a perspective view of the distal region of an alternative
embodiment of apparatus constructed in accordance with the present
invention;
FIG. 8 is a perspective view of the distal region of the apparatus
of the present invention showing an alternative embodiment of the
stabilization members;
FIGS. 9A, 9B and 9C are end views, taken along view line 9-9 of
FIG. 8, depicting various deployment positions of the stabilization
members of FIG. 8;
FIG. 10 is a perspective view of the distal region of the apparatus
of the present invention showing an alternative embodiment of the
stabilization members;
FIG. 11 is a perspective view of the distal region of the apparatus
of the present invention showing another alternative embodiment of
the stabilization members;
FIGS. 12A-12C are end views, taken along view line 12-12 of FIG.
11, depicting various deployment positions of the stabilization
members of FIG. 11;
FIG. 13 is a view of an alternative embodiment of apparatus
constructed in accordance with the present invention;
FIGS. 14A and 14B are, respectively, perspective top and bottom
views of a distal region of the apparatus of FIG. 13;
FIG. 15 is a partial side view, partly in section, of the catheter
shaft of FIGS. 13 and 14 deployed in contact with tissue;
FIG. 16 is a side view of the handle portion of the apparatus of
FIG. 13;
FIGS. 17A and 17B are, respectively, top and side sectional views
of the distal region of an alternative embodiment of the apparatus
of the present invention;
FIG. 18 is a perspective top view of the distal region of a further
alternative embodiment of the apparatus of the present
invention;
FIG. 19 is a view of a further alternative embodiment of apparatus
of the present invention; and
FIGS. 20A and 20B are, respectively, perspective top and side views
of a distal region of the apparatus of FIG. 19.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates generally to apparatus and methods
for percutaneously performing surgery within an organ or vessel.
The apparatus of the present invention comprises a catheter
including a stabilizing catheter shaft which percutaneously may be
disposed within an organ. A guide member engaged with the catheter
shaft includes an end region that may be selectively articulated to
a position at an angle to a longitudinal axis of the catheter,
including a position substantially orthogonal to the longitudinal
axis. The end region carries an end effector (e.g., an ablative or
mechanical cutting device) for treating tissue. Severed or ablated
tissue may be aspirated through the catheter to its proximal end
for disposal. The catheter shaft, either alone or in conjunction
with stabilizing members, and the guide member, provides precise
control over the location of the end region, and thus, the end
effector.
The present invention therefore offers a device having a directable
end region and end effector for performing surgery that provides a
degree of control heretofore unattainable. While the invention is
described hereinafter as particularly useful in the emerging field
of transmyocardial revascularization, apparatus constructed in
accordance with the present invention may be advantageously used in
performing surgery on other organs or vessels, such as the
intestines, blood vessels or the brain cavities. In addition, while
the present invention is described herein in the context of a
mechanical cutting system, the control and stabilization apparatus
of the present invention may be advantageously used with other
types of cutting elements, such as lasers, cryogenic cutters or
radio-frequency ablation devices.
Referring to FIG. 1, illustrative apparatus 20 constructed in
accordance with the present invention is described. Apparatus 20
includes a two-part catheter formed of catheter shaft 21 and guide
member 22. Apparatus 20 includes distal region 23 within which
guide member 22 has end region 25 that is selectively movable
between a transit position parallel to longitudinal axis 24 of
catheter shaft 21 and a working position (as shown) substantially
orthogonal to longitudinal axis 24. Distal region 23 preferably
includes an end effector, described in greater detail hereinbelow,
for ablatively or mechanically cutting tissue to attain a treatment
goal.
End region 25 of guide member 22 may be positioned longitudinally
with respect to catheter shaft 21 by imparting relative movement
between guide member 22 and catheter shaft 21 using handle assembly
26. Catheter shaft 21 preferably includes a plurality of
stabilizing members 27 to support and stabilize distal region 23 of
the apparatus within the hollow-body organ.
Apparatus 20 is coupled via cable 28 to controller 29. In a
preferred embodiment wherein the end effector comprises a rotating
cutting head, controller 29 includes a motor and control logic for
rotating the cutting head responsive to commands input at handle
assembly 26 or a footpedal (not shown) and a vacuum source for
aspirating severed tissue from the treatment site. Controller 29
optionally may further include RF circuitry (shown in dotted line)
for energizing the cutting head to cauterize tissue as it is cut.
Alternatively, controller 29 may include a laser source or radio
frequency circuitry for causing laser or RF ablation, respectively,
using a suitable end effector.
Referring now to FIGS. 2 and 3, distal region 23 of apparatus 20 is
described in greater detail. In FIG. 2, distal region 23 includes
end region 25 of guide member 22 disposed in sliding engagement in
groove 30 of catheter shaft 21. Catheter shaft 21 may be
constructed of a flexible material commonly used in catheter
products, such as nylon, polyethylene or polyurethane, and contains
lateral grooves 31 and 32 that accept a mating portion of guide
member 22 in sliding engagement. Catheter shaft 21 may have an
ellipsoidal shape to stabilize the catheter shaft and may include
two spaced-apart wire stiffeners that terminate in barbs 33. Barbs
33 are designed to engage an interior surface of an organ, for
example, the apex of the left ventricle, to reduce rotation of the
catheter shaft when the end effector is actuated. Alternatively,
catheter shaft 21 may be formed of a material having sufficient
stiffness that the wire stiffeners may be omitted over most of the
length of the catheter shaft.
Guide member 22 includes end region 25 carrying an end effector and
flanges 34 and 35 that slidingly engage grooves 31 and 32. End
region 25 may be articulated in region 36 using control wires or a
temperature actuated shape-memory alloy steering mechanism, such as
described in the aforementioned patents to Imran. Guide member 22
may be constructed of a spring material (commonly called a Bowden)
with spaces in-between the coils to allow it to bend when it is
pulled by a control wire asymmetrically, as previously known in the
art. Alternatively, guide member 22 may be constructed of a stiffer
material such as polyimide coated over a braided steel tubular
structure, such as employed in previously known neuro-navigational
endoscope devices. In this case, slits are provided on the inside
of the bend in region 36 so that the guide member bends in the
direction of the slits. The slits allow a tight bend radius which
may not otherwise be achievable.
Guide member 22 preferably includes a lumen, as described
hereinafter, through which tissue may be evacuated from a treatment
site by suction. Accordingly, guide member 22 may also be formed
from a loosely wound spring reinforced with a soft elastomeric
coating. The elastomeric coating advantageously serves the
following functions: it provides sealing along the length of the
guide member required to maintain adequate suction through the
lumen; it prevents collapse of the lumen in the presence of applied
suction; it resists kinking of the coils of the spring; and it also
enables the guide member to be bent to relatively tight radii.
Reinforced tubing suitable for use as guide member 22 is available
from Adam Spence Corporation, Wall, N.J.
In the above-described embodiments, end region 25 of guide member
22 is movable from a transit position lying parallel to the
longitudinal axis of catheter shaft 21 to a working position
wherein end region 25 is articulated to a position substantially
orthogonal to the longitudinal axis of the catheter shaft. In
addition, end region 25 may be constructed to enable it to be
locked in position at any angle a that may be desired for a given
application.
With respect to FIGS. 3A and 3B, stabilization members 27 project
outwardly from apertures 37 on either side of catheter shaft 21 in
distal region 23. Illustratively, stabilization members 27 comprise
four circumferentially-oriented hoops formed of flexible wires
27a-27d. In one preferred embodiment, depicted in FIGS. 3, wires
27a-27d comprise a continuous coil having its distal end affixed to
catheter shaft 21 and its proximal end connected to handle assembly
26 via push wire 38. The turns of the coil are slidably disposed in
lumens within catheter shaft 21 that interconnect apertures 37 on
either side of the catheter shaft. When push wire 38 is urged in
the distal direction, wires 27a-27d expands outwards by
illustrative distances h.sub.1-h.sub.4 to contact and conform to
the topology of the interior wall of the hollow-body organ or
vessel. Wires 27a-27d also may be retracted against catheter shaft
21 by pulling push wire 38 in the proximal direction.
Accordingly, wires 27a-27d may be moved from a retracted position
in which they are retracted against distal region 23 of catheter
shaft 21 to an expanded position in which they engage a wall of the
organ and urge end region 25 into engagement with an opposing wall
of the organ, thereby stabilizing catheter shaft 21 against
rotation.
Stabilization members 27 may be constructed of any suitable elastic
material, including stainless steel, spring steel, nickel-titanium
alloys, and a variety of plastics. A nickel-titanium alloy is
preferred where wires 27a-27d comprise a continuous coil, as in
FIG. 3B. In the contracted mode, catheter shaft 21 and guide member
22 have a relatively small profile, for example, 2-3 mm. Upon
actuation of the control means in handle assembly 26, wires 27a-27d
expand out as shown in FIG. 3B to form a basket shape that spans
and conforms to the lumen of the organ or vessel.
Where stabilization members 27 comprise a single coil, as in FIG.
3B, they may be actuated by a single control means. Alternatively,
as described hereinafter with respect to FIG. 8, each of
stabilization members 27 may be individually adjusted to conform to
the shape of the cavity of the hollow-body organ. Stabilization
members 27 may alternatively be oriented parallel to the
longitudinal axis of apparatus 20, as described hereinafter with
respect to FIG. 8.
The longitudinal position of end region 25 with respect to catheter
shaft 21 may be adjusted by sliding guide member 22 in groove 30 of
the catheter shaft. Handle assembly 26 preferably includes means,
described hereinafter, for moving guide member with respect to
catheter shaft 21 so that end region 25 may be positioned at a
series of vertical locations. In addition, stabilization members 27
may be adjusted to provide some control over the lateral
positioning of the catheter shaft and guide member with respect to
the interior wall of the organ or vessel. Thus, apparatus 20
enables a matrix of treatment sites to be accessed without removing
and repositioning the apparatus.
Referring now to FIG. 4, end effector 40 (also referred to
hereinafter as a "micromorcellator") is described as illustratively
comprising a rotary cutting member and drive arrangement.
Micromorcellator 40 includes cutting head 41 comprising tubular
element 42. Distal edge 42a of tubular element 42 includes a
sharpened bevel 43. Cutting head 41 is affixed to drive rod 45,
which preferably includes soft plastic or elastomeric coating 45a,
as described hereinabove, to maintain suction through lumen 44. The
vacuum source in controller 29 aspirates the severed tissue through
lumen 44, if provided.
Orientation of end region 25 of guide member 22 is accomplished by
control wire 46, which is slidingly disposed in lumen 47 of guide
member 22. As described hereinabove, guide member 22 preferably
comprises a spring material with spaces in-between the coils to
allow it to bend when control wire 46 is retracted in a proximal
direction. Alternatively, guide member 22 may be constructed of
polyimide coated over a braided steel tube and includes slits on
the inside of bend region 36 so that end region 25 bends in the
direction of the slits when control wire 46 is retracted in a
proximal direction.
Cutting head 41 is connected to the motor of controller 29 via
drive rod 45. Drive rod 45 may be formed of a flexible tube such as
a bowden or a covered coil or may be formed of a plastic having
both high torquability and flexibility. Drive rod 45 is disposed in
lumen 44 for a limited range of reciprocation, e.g., up to 3.0 cm,
to permit extension of cutting head 41 beyond the end of guide
member 22. When end region 25 is in its transit position, cutting
head 41 is disposed just below distal endface 48 of guide member
22. Drive rod 45 is hollow and preferably includes a covering of a
soft plastic or elastomeric material to allow the application of a
negative pressure to aspirate the severed tissue.
Applicant expects that high speed rotation of cutting head 41 will
generate frictional heating of the tissue surrounding the cutting
head, thereby causing coagulation of the tissue with minimal
thermal damage to the surrounding tissue. Alternatively, tubular
member 42 of cutting head 41 may comprise an electrically
conductive material and be electrically coupled to the optional
radio-frequency generator circuitry in controller 29 to provide
coagulation of the edges of a channel formed in the tissue by
cutting head 41. In this embodiment, tubular element 42 serves as
the electrode in a monopolar coagulation arrangement. In addition,
a second electrode (not shown) may be formed on the working end
spaced apart from the cutting head 41, so that tubular member 42
serves as one electrode of a bipolar coagulation arrangement.
Applicant expects that the sealing action produced by RF
coagulation, if provided, will simulate the lesions produced by a
laser.
With respect to FIGS. 5A and 5B, illustrative handle assembly 50 is
described. Handle assembly 50 includes lower portion 51 affixed to
catheter shaft 21 and upper portion 52 affixed to guide member 22.
Upper portion 52 is slidingly engaged in lower portion 51, so that
guide member 22 may be selectively translated longitudinally with
respect to catheter shaft 21 by rotating knob 53. Lower portion 51
of handle assembly 50 includes hand grip 54, and button 55 for
controlling the extension of stabilization members 27. Button 55
slides in slot 56 of lower portion 51 to extend or retract
stabilization members 27 via push wire 38.
Upper portion 52 includes indicator 57a that may be selectively
aligned with indicators 57b, so that the channels formed by end
effector 40 are positioned at a series of spaced-apart locations.
Cable 28 extends from upper portion 52 and connects the working end
of apparatus 20 to controller 29. Upper portion 52 also includes
button 58 which may be moved in slot 59 to control the articulation
of end region 25 of guide member 22, and depth control lever 60
disposed in slot 61. Depth control lever 60 is moved within slot 61
to control reciprocation of cutting head 41 from end region 25.
Slot 61 has a length so that when button 60 is moved to fully
extend cutting head 41 from guide member 22, a proximal portion of
tubular member 42 remains within guide member 22. In addition, or
alternatively, a user-adjustable limit bar (not shown) may be
provided in slot 61 to select the maximum extension of cutting head
41 desired for a particular application.
RF button 62 also may be provided to control activation of the
optional RF circuitry of controller 29 to coagulate tissue
surrounding the channel formed by micromorcellator 40. RF button
also could take the form of a microswitch located within slot 61 of
handle assembly 50, so as to provide automatic activation of the RF
coagulation feature for a short period of time when depth control
lever 60 is advanced to contact the user-adjustable limit bar.
It will therefore be seen that handle assembly 50 provides for
longitudinal movement of end region 25 with respect to catheter
shaft 21 via relative movement between upper portion 52 and lower
portion 51 (using knob 53); provides selective deployment of
stabilization members 27 via button 55; selective orientation of
end region 25 via button 58; control over the depth of the channels
formed by end effector 40 via depth control lever 60; and,
optionally, activation of an RF coagulation feature via button
62.
Referring now to FIGS. 6A-6C, operation of apparatus 20 in the
context of performing transmyocardial revascularization is
described. In FIG. 6A, distal region 23 of apparatus 20 is shown
positioned in a patient's left ventricular cavity, using techniques
which are per se known. Specifically, distal region 23 of apparatus
20 is inserted via a femoral artery, and is maneuvered under
fluoroscopic guidance in a retrograde manner up through the
descending aorta, through aortic arch 201, and down through
ascending aorta 202 and aortic valve 203 into left ventricle 204.
Previously known imaging techniques, such as ultrasound, MRI scan,
CT scan, or fluoroscopy, may be used to verify the location of the
distal region 23 within the heart.
Insertion of apparatus 20 into the left ventricle is with guide
member 22 in its distal-most position with stabilization members 27
fully retracted and end region 25 in its transit position. As barbs
33 of catheter shaft 21 engage apex 205 of the left ventricle,
catheter shaft 21 (and guide member 22) preferentially bends in
regions 65 and 66 to form a "dog-leg", in which distal region 23
becomes urged against a lateral wall of the ventricle. Regions 65
and 66 where the bends take place may be made flexurally weaker
than the remainder of the catheter shaft to aid in the bending of
the catheter at these locations.
Referring to FIG. 6B, button 55 is advanced in slot 56 of handle
assembly 50 to extend stabilization members 27 so that they engage
the septal wall of the left ventricle and urge the end effector
against left ventricular wall 206. The dog-leg bends in regions 65
and 66 allow the catheter to be pushed onto the left ventricular
wall while the stabilization members push against the septum. End
region 25 of guide member 22 is then rotated to its working
position by retracting button 58 along slot 59 of handle assembly
50, thus causing end region 25 to be positioned substantially
orthogonally to the longitudinal axis of catheter shaft 21.
The motor and vacuum source of controller 29 are then actuated to
cause cutting head 41 to rotate and to induce negative pressure in
lumen 44 of micromorcellator 40. The clinician then pushes depth
control lever 60 distally in slot 61, causing cutting head 41 to be
advanced beyond distal endface 48 of guide member 22 and engage the
endocardium. When micromorcellator 40 engages the endocardium, a
reaction force is generated in catheter shaft 21 that tends both to
push end region 25 away from the tissue and to cause the catheter
shaft to want to rotate. The relatively flat configuration of
catheter shaft 21, in conjunction with barbs 33, is expected to
adequately counteract the torque induced by operation of the
micromorcellator. In addition, stabilization members 27 function to
counteract both these outward reaction and torque effects.
As micromorcellator 40 is advanced to form channel 207 in the left
ventricular wall, tissue severed by cutting head 41 is suctioned
into lumen 44 and aspirated to the proximal end of apparatus 20 via
the vacuum source of controller 29. The depth of channel 207, which
is proportional to the movement of depth control lever 60 in slot
61, may be predetermined using conventional ultrasound techniques,
MRI scanning, or other suitable methods. As channel 207 is formed,
tissue severed from the ventricular wall is aspirated through lumen
44 of guide member 22, thereby reducing the risk of embolization of
the severed material. In addition, applicant expects that the use
of suction through lumen 44 will assist in stabilizing the
micromorcellator, and tend to draw tissue into the cutting
head.
Once micromorcellator 40 has achieved its maximum predetermined
depth, cutting head 41 is withdrawn from channel 207 by retracting
depth control lever 60 to its proximal-most position, thereby
returning cutting head 41 to a position just below distal endface
48 of end region 25 of guide member 22. It is expected that
rotation of cutting head 41 will generate sufficient frictional
heat in the tissue contacting the exterior of cutting head 41 to
coagulate the tissue defining the channel.
Optionally, RF button 62 may be depressed on handle assembly 50 to
apply a burst of RF energy to the edges of channel 207 as
micromorcellator 40 achieves its maximum predetermined depth, and
while cutting head 41 is stationary, rotating or being withdrawn
from the channel. If provided, this burst of RF energy is expected
to further coagulate the tissue defining the walls of channel 207
and modify the surface properties of the tissue.
As shown in FIG. 6C, a series of vertically aligned spaced-apart
channels 207 may be formed in left ventricular wall 207 by sliding
upper portion 52 proximally within lower portion 51 of handle
assembly 50 (by rotating knob 53). Cutting head 41 is then advanced
to form a further channel 207 in the tissue, and the tissue may
also be coagulated with a burst of RF energy. When upper portion 52
has been retracted to its proximal-most position, button 55 is
adjusted as described above with respect to FIGS. 3A and 3B to
cause the catheter shaft to rotate several degrees about its axis.
Stabilization members 27 are again extended to contact the septal
wall, causing micromorcellator 40 to be urged against left
ventricular wall 206 in a region laterally spaced apart from the
initial line of channels 207.
The foregoing methods enable a matrix of channels to be formed
illustratively in the left ventricular wall. It will of course be
understood that the same steps may be performed in mirror image to
stabilize the apparatus against the left ventricular wall while
actuating the end effector to produce a series of channels in the
septal region. In accordance with presently accepted theory, the
formation of such channels in the endocardium or septal region
enables oxygenated blood in the left ventricle to flow directly
into the myocardium and thus nourish and oxygenate the muscle. It
is believed that these channels may be drilled anywhere on the
walls of the heart chamber, including the septum, apex and left
ventricular wall, and the above-described apparatus provides this
capability.
Referring now to FIG. 7, the distal region of an alternative
embodiment of the apparatus of the present invention is described.
Apparatus 70 is similar to apparatus 20 described hereinabove, but
includes wires 71 and 72 forming a dual-rail on which catheter
shaft 73 glides, thereby reducing unwanted rotation of distal
region 74 and end region 75. Distal end 76 of the dual-rail
includes cushion 77 having barbs 78 for anchoring the catheter
shaft in the apex of the left ventricle to prevent inadvertent
rotation of catheter shaft 73. Guide member 79 has an inner
diameter suitable for carrying one of a variety of end effectors
81, such as a laser fiber, a radio frequency applying device,
micromorcellator as described hereinabove, or slit needles, as in
the above-mentioned patent to Taheri.
Dual-rail embodiment 70 may be used without stabilization members,
or alternatively catheter shaft 73 may include the stabilization
members of FIGS. 3 or as described hereinbelow. Wires 71 and 72
also may be formed from a resilient material, e.g., stainless steel
or a nickel-titanium alloy, so that when they exit catheter shaft
73 they diverge from one another and give the catheter a larger and
more stable base. In this case, cushion 77 preferably comprises an
elastomeric material that allows the distance between the tips of
wires 71 and 72 to increase beyond the diameter of the catheter.
Wires 71 and 72 may have other than circular cross-sections and may
take the form of, for example, ribbons.
Wires 71 and 72, in cooperation with a distally-directed axial
force exerted on the handle assembly by the clinician, serve to
anchor the catheter against a lateral wall of the left ventricle,
while catheter shaft 74 and guide member 79 are advanced along the
dual-rail. Like apparatus 20, apparatus 70 may include flexurally
weaker locations along its length to aid in positioning distal
region 74 within the left ventricle.
The dual-rail design of apparatus 70 also may be advantageously
employed to determine the location of end region 75 and end
effector 81 with respect to the interior of the hollow-body organ
or vessel. In this embodiment, wires 71 and 72 are electrically
connected within cushion 77 and have a uniform resistance per unit
length. Electrodes 80 are positioned in distal end 82 of catheter
shaft 73 to measure the resistance of wires 71 and 72 between the
electrodes.
The resistance between electrodes 80 may be measured, for example,
by ohmmeter circuitry, to determine the distance between the distal
end 82 of the catheter shaft and the apex of the left ventricle. In
conjunction with the displacement between the upper and lower
portions of the handle assembly (see FIGS. 5), the position of end
region 75 and end effector 81 may be determined relative to the
apex of the heart. This position information may be sampled using
suitable analog to digital circuitry, and displayed on a display
unit to aid the physician in determining where to place the
channels in the heart wall.
Referring now to FIGS. 8 and 9A-9C, a first alternative embodiment
of the stabilization members of the present invention are
described. In FIG. 8, the distal region of apparatus 90 similar to
that of FIG. 1 is shown, in which like components are indicated by
like reference numerals. Apparatus 90 includes catheter shaft 21
including barbs 33 and guide member 22 including end region 25.
Stabilization members 91a-91d project from proximal apertures 92
and distal apertures 93, and comprise individual
longitudinally-oriented flexible wires. Wires 91a-91d enter lumens
in catheter shaft 21 through apertures 92 and extend proximally to
handle assembly 26. Each of wires 91a-91d preferably has a
respective button (similar to button 55 in FIGS. 5) on handle
assembly 26 for selectively controlling the extension of the
wires.
Accordingly, wires 91a-91d of the embodiment of FIG. 8 may be moved
from a retracted position in which they are retracted against
distal region 23 of catheter shaft 21 to an expanded position in
which they engage a wall of the organ and urge end region 25 into
engagement with an opposing wall of the organ, thus stabilizing
catheter shaft 21 against rotation.
As illustrated in FIGS. 9A-9B, each of stabilization members 91
preferably may be selectively extended a different amount,
therefore causing distal region 23 to rotate about its longitudinal
axis. For example, in FIG. 9A, wire 91a is extended from distal
region 23 a greater distance, causing a larger bow in wire 91a,
while wire 91d is extended a smaller distance, causing a smaller
bow therein. Consequently, if each of wires 91a-91d contacts a wall
of the organ, catheter shaft 23 will have a tendency to rotate in a
counterclockwise direction (viewed from the distal end).
Conversely, reversing the extensions of wires 91a and 91d, as in
FIG. 9C, will cause rotation in the opposite direction. It is
therefore seen that by individually controlling the extension of
the stabilization members 91, the position of the catheter with
respect to an interior lateral wall of the hollow-body organ can be
controlled.
Referring now to FIG. 10 an alternative embodiment of a
stabilization arrangement is described. Apparatus 100 includes
catheter shaft 101 and guide member 102. Except for stabilization
members 103, which in FIG. 10 comprise horizontal inflatable ribs,
apparatus 100 is similar to apparatus 20 of FIG. 1.
As described hereinabove, guide member 102 moves relative to
catheter shaft 101 to enable the clinician to form a series of
vertically aligned channels in the myocardium. Once a line of
channels has been formed, the catheter must be moved laterally to a
new location and the procedure repeated until the desired number of
channels has been achieved. One expedient for doing so, for
example, applicable to the apparatus of FIG. 7, is to withdraw the
catheter slightly, rotate it and reposition it at a different
location on the left ventricular wall. The stabilization
arrangement of FIG. 10 instead facilitates lateral movement by
deflating ribs 103, rotating catheter shaft 21, and then
re-inflating ribs 103.
Specifically, when inflated, stabilization members 103 provide a
degree of hoop strength that ensures proper contact of the distal
face of end region 106 with the wall of the hollow-body organ or
vessel at all times. Once a vertical row of channels has been
formed, stabilization members 103 are deflated by the clinician and
end region 106 is moved to a new lateral position. The
stabilization members are fully re-inflated and another vertical
row of channels is formed, as discussed hereinabove.
With respect to FIGS. 11 and 12A-12C, another embodiment of the
apparatus of the present invention is described in which the
stabilization members comprise longitudinally-oriented balloons.
Apparatus 110 is otherwise similar to the apparatus of FIG. 8, and
includes catheter shaft 111, guide member 112, and end region 113.
Stabilization elements 114a-114c comprise balloons, preferably
formed of a compliant material, such as polyurethane, silicone or
latex. The handle assembly for apparatus 110 includes valving means
for selectively individually inflating balloons 114a-114c. As shown
in FIGS. 12A-12C, balloons 114a-114c may be selectively inflated
via inflation lumens (not shown) in catheter shaft 111 to stabilize
apparatus 110 within a hollow-body organ, and to rotate catheter
shaft 111 (and end region 113) in a manner similar to that
described above with respect to FIGS. 9A-9C.
Referring now to FIG. 13, a further alternative embodiment of
apparatus constructed in accordance with the present invention is
described. Apparatus 120 comprises a two-part catheter formed of
catheter shaft 121 and guide member 122. Apparatus 120 includes
distal region 123 within which guide member 122 has end region 125
that is selectively movable between a transit position parallel to
longitudinal axis 124 of catheter shaft 121 and a working position
(as shown), substantially orthogonal to longitudinal axis 124.
Distal region 123 preferably includes an end effector, as described
in detail hereinabove.
End region 125 of guide member 122 may be positioned longitudinally
with respect to catheter shaft 121 by imparting relative movement
between guide member 122 and catheter shaft 121 using handle
assembly 126. Catheter shaft 121 includes stabilizing assembly 127
to support and stabilize distal region 123 of the apparatus within
an organ or vessel.
Apparatus 120 is coupled via cable 128 to controller 129. In a
preferred embodiment, wherein the end effector comprises a flexible
wire having a sharpened tip, controller 129 includes a hydraulic or
pneumatic piston, valve assembly and control logic for extending
and retracting the end effector beyond the distal endface of end
region 125 responsive to commands input at handle assembly 126 or a
footpedal (not shown). Controller 129 optionally may further
contain RF generator circuitry for energizing electrodes disposed
on the end effector to cause a controlled degree of necrosis at the
treatment site.
Referring now to FIGS. 14A and 14B, distal region 123 of apparatus
120 is described in greater detail. In FIG. 14A, distal region 123
includes end region 125 of guide member 122 disposed in sliding
engagement in track 130 of catheter shaft 121, as described
hereinabove with respect to the embodiment of FIG. 1. Guide member
122 includes end region 125 carrying end effector 134 and flanges
135 that slidingly engage grooves 131 and 132. End region 125 may
be articulated in region 136 using control wires or a temperature
actuated shape-memory alloy steering mechanism, as described
hereinabove.
End region 125 of guide member 122 is movable from a transit
position lying parallel to longitudinal axis 124 of catheter shaft
121 to a working position wherein end region 125 is articulated to
a position substantially orthogonal to the longitudinal axis of the
catheter shaft. In addition, end region 125 may be constructed to
enable it to be locked in position at any angle a that may be
desired for a given application.
Stabilization assembly 127 comprises flat band 137 of resilient
material, such as stainless steel, that projects outwardly from
catheter shaft 121 in distal region 123. Illustratively,
stabilization assembly 127 comprises multiple loops 127a-127c of
band 137. Band 137 has its distal end affixed to the distal end of
catheter shaft 121, and its proximal end connected to handle
assembly 126. Band 137 passes through an interior lumen of catheter
shaft 121 (see FIG. 15) and exits to the exterior surface of
catheter shaft 121 in distal region 123. Crossbars 138 permit band
137 to be pulled flat against the exterior surface of catheter
shaft 121, as shown in FIG. 14B, or urged in a distal direction to
form loops 127a-127c.
Referring to FIG. 15, in which guide member 122 is omitted for
clarity, when the proximal end of band 137 is urged in the distal
direction, loops 127a-127c expand outwardly by illustrative
distances h.sub.1-h.sub.3 to contact and conform to the topology of
interior wall T of an organ or vessel. Accordingly, loops 127a-127c
may be moved from a retracted position in which they are retracted
against an exterior surface of distal region 123 of catheter shaft
121 (FIG. 14B) to an expanded position (FIG. 14A) in which they
engage a wall of an organ or vessel.
In the position shown in FIG. 14A, stabilization assembly 127 urges
end region 125 into engagement with an opposing wall of the organ,
thereby stabilizing catheter shaft 121 against rotation. Band 137
may be constructed of any suitable elastic material, including
stainless steel, spring steel, nickel-titanium alloys, and a
variety of plastics. In the contracted mode, catheter shaft 121 and
guide member 122 have a relatively small profile, for example, 2-3
mm.
The longitudinal position of end region 125 with respect to
catheter shaft 121 may be adjusted by sliding guide member 122 in
track 130 of the catheter shaft. Handle assembly 126 preferably
includes means, described hereinafter, for moving guide member 122
with respect to catheter shaft 121 so that end region 125 may be
positioned at a series of longitudinal locations In addition,
stabilization assembly 127 may be adjusted to provide some control
over the lateral positioning of the catheter shaft and guide member
with respect to the interior wall of the organ or vessel. Thus,
apparatus 120 enables a matrix of treatment sites to be accessed
without removing and repositioning the apparatus.
With respect to FIG. 8, illustrative handle assembly 126 is
described. Handle assembly 126 includes lower portion 140 affixed
to catheter shaft 121 and upper portion 141 affixed to guide member
122. Upper portion 141 is slidingly engaged in lower portion 140,
so that guide member 122 may be selectively translated
longitudinally with respect to catheter shaft 121 by rotating knob
142. Upper portion 141 includes ribbed bonnet 143, which collapses
and expands to enclose lower portion 140 as upper portion 141 is
moved in the proximal and distal directions, respectively. Lower
portion 140 of handle assembly 126 includes indentations 144
forming a hand grip.
Threaded post 145 is coupled to the proximal end of band 137, and
slides in a slot (not visible in FIG. 16) in the lower surface of
catheter shaft 121. Thumbwheel 146 is threaded onto post 145. Post
145 and thumbwheel 146 permit the proximal end of band 137 (see
FIG. 15) to be urged in the proximal and distal directions, for
example, to deploy stabilization assembly 127. Band 137 then is
locked into position by tightening thumbwheel 146 on post 145
against the lower surface of catheter shaft 121.
Upper portion 141 includes indicator 147a that may be selectively
aligned with indicators 147b, so that the treatment sites are
positioned at a series of spaced-apart locations. Cable 128 extends
from upper portion 141 and connects the end effector of apparatus
120 to controller 129. Button 148 disposed on the top surface of
upper portion 141 may be depressed to command the control logic of
controller 129 to reciprocate the end effector from end region 125,
and optionally, cause necrosis at the treatment site. Button 149,
disposed in a slot in the upper surface of the proximal end of
guide tube 122 (not visible in FIG. 16) is coupled to a tendon
affixed to end region 125, and may be moved in the proximal and
distal directions to control the degree of articulation of end
region 125 and the end effector.
Handle assembly 126 therefore provides for longitudinal movement of
end region 125 with respect to catheter shaft 121 via relative
movement between upper portion 141 and lower portion 140 (using
knob 142); provides selective deployment of stabilization assembly
127 (using post 145 and thumbwheel 146); selective orientation of
end region 125 (using button 149); and control over operation of
the end effector (using button 148).
Referring now to FIGS. 17A and 17B, a yet further alternative
embodiment of the stabilization assembly of the apparatus of the
present invention is described. Apparatus 150 is similar to
apparatus 120 described hereinabove, but band 137 that forms
stabilization assembly 127 of apparatus 120 is replaced by
transversely mounted fixed wire hoops 151a-151d. In FIG. 17A, the
guide catheter is omitted from track 152 for clarity. Wire hoops
151a-151d, illustratively four in number, have their ends affixed
to the lateral faces of catheter shaft 153 so that, when
unconstrained, the hoops return to a position substantially
orthogonal to the longitudinal axis of catheter shaft 153. Wire
hoops preferably comprise a sturdy, elastic plastic or metal alloy,
such as nickel-titanium.
In FIG. 17B, catheter shaft 153 is shown disposed within outer
sheath 154. When retracted within outer sheath 154, hoops 151a-151d
are deformed so that they lie adjacent to the exterior surface of
catheter shaft 153. Guide member 155 and catheter shaft 153 are
delivered to the left ventricle while enclosed within outer sheath
154. Once distal endface 156 is positioned against the apex of the
left ventricle, for example, as determined by fluoroscopy, outer
sheath 154 is retracted proximally. This permits hoops 151a-151d to
resume their preferred shape, and urge guide member 155 against the
opposing wall of the left ventricle. Hoops 151a-151d serve to
stabilize and counteract reaction forces generated by operation of
the end effector.
With respect to FIG. 18, a still further alternative embodiment of
the stabilization assembly of the present invention is described.
In apparatus 160 of FIG. 18, the catheter shaft is omitted, and
guide member 161 is supported by a plurality of bands 162 (only two
are shown in FIG. 18). Guide member 161 and bands 162 extend from
within outer sheath 163. Each band 162 preferably terminates in
spool 164 when it is extended from within outer sheath 163. Spools
164 contact one wall of the organ or vessel and urge end region 165
of guide member 161 into contact with the opposing wall of the
organ or vessel. Preferably, the length of each band 162 may be
adjusted using suitable means disposed on the handle assembly.
Operation of guide member 161 and end effector 166 are the same as
described herein for other embodiments of the present
invention.
Referring to FIGS. 19 and 20, another embodiment of apparatus of
the present invention is described. Apparatus 170 comprises a
two-part catheter formed of catheter shaft 171 and guide member
172, and is coupled via cable 178 to controller 179 that performs
the functions described above with respect to controller 129 of the
embodiment of FIG. 13.
Apparatus 170 includes distal region 173 within which guide member
172 has end region 175 that is selectively movable between a
transit position parallel to longitudinal axis 174 of catheter
shaft 171 and a working position (as shown), substantially
orthogonal to longitudinal axis 174. Distal region 173 preferably
includes an end effector, as described in detail hereinabove. End
region 175 of guide member 172 may be positioned longitudinally
with respect to catheter shaft 171 by imparting relative movement
between guide member 172 and catheter shaft 171 using handle
assembly 176. Catheter shaft 121 includes stabilizing element 177
to support and stabilize distal region 173 of the apparatus within
an organ or vessel.
Distal region 173 of apparatus 170 is described in greater detail
with respect to FIGS. 20A and 20B. Distal region 173 includes end
region 175 of guide member 172 disposed in sliding engagement in
track 180 of catheter shaft 171, as described hereinabove with
respect to other embodiments. Guide member 172 includes end region
175 carrying end effector 181 and flanges 182 that slidingly engage
grooves 183 and 184. End region 175 may be articulated in region
185, as may be constructed and operated as described hereinabove
for other embodiments.
Stabilization element 177 comprises wire or band 186 of resilient
material, such as stainless steel, that exits catheter shaft 171
through skive 187, and is fixed to catheter shaft 171 near distal
end 188. When deployed within a hollow organ, such as a chamber of
the heart, as depicted in FIG. 20B, stabilization element 177 forms
a plurality of sinusoidal bends 177a-177c that support distal end
173 of catheter shaft 171. Stabilization element 177 preferably
comprises a material having a shape-memory and that is capable of
reforming to a desired shape when extended through skive 187.
While preferred illustrative embodiments of the invention are
described, it will be apparent to one skilled in the art that
various changes and modifications may be made without departing
from the invention, and the appended claims are intended to cover
all such changes and modifications that fall within the true spirit
and scope of the invention.
* * * * *
References