U.S. patent application number 10/913608 was filed with the patent office on 2006-02-09 for ventricular partitioning device.
This patent application is currently assigned to CardioKinetix, Inc.. Invention is credited to Alexander Khairkhkahan, Serjan D. Nikolic, Branislav Radovancevic, Hugh R. Sharkey.
Application Number | 20060030881 10/913608 |
Document ID | / |
Family ID | 35159737 |
Filed Date | 2006-02-09 |
United States Patent
Application |
20060030881 |
Kind Code |
A1 |
Sharkey; Hugh R. ; et
al. |
February 9, 2006 |
Ventricular partitioning device
Abstract
This invention is directed to a partitioning device for
separating a patient's heart chamber into a productive portion and
a non-productive portion. The device is particularly suitable for
treating patients with congestive heart failure. The partitioning
device has a frame-reinforced, expandable membrane which separates
the productive and non-productive portions of the heart chamber.
The proximal ends of the ribs of the frame have tissue penetrating
elements about the periphery thereof which are configured to
penetrate tissue lining the heart wall at an angle approximately
perpendicular to a longitudinal axis of the partitioning device.
The partitioning device has a hub with a non-traumatic distal end
to engage the ventricular wall.
Inventors: |
Sharkey; Hugh R.; (Redwood,
CA) ; Khairkhkahan; Alexander; (Palo Alto, CA)
; Nikolic; Serjan D.; (San Francisco, CA) ;
Radovancevic; Branislav; (Houston, TX) |
Correspondence
Address: |
Edward J. Lynch;DUANE MORRIS LLP
Spear Tower, Suite 2000
One Market
San Francisco
CA
94105
US
|
Assignee: |
CardioKinetix, Inc.
|
Family ID: |
35159737 |
Appl. No.: |
10/913608 |
Filed: |
August 5, 2004 |
Current U.S.
Class: |
606/213 |
Current CPC
Class: |
A61B 17/12172 20130101;
A61B 2017/12095 20130101; A61B 2017/00526 20130101; A61B 17/12122
20130101 |
Class at
Publication: |
606/213 |
International
Class: |
A61B 17/08 20060101
A61B017/08 |
Claims
1. A device for treating a patient with congestive heart failure by
partitioning a chamber of the patient's heart into a primary
productive portion and a secondary non-productive portion,
comprising: a. a partitioning component which has an expandable
frame formed of a plurality of ribs having distal ends secured to a
central hub and free outwardly flared proximal ends and which has a
proximal, pressure receiving face forming a recess in an expanded,
deployed configuration defining in part the primary productive
portion of the patient's heart chamber to be partitioned; and b. a
plurality of tissue penetrating securing elements disposed at free
ends of the ribs configured to penetrate tissue lining the heart
chamber at an angle essentially perpendicular to the center line
axis of the partitioning device to secure the periphery of the
partitioning device to the heart chamber.
2. The device of claim 1 wherein reinforced partitioning component
has a contracted configuration for delivery to patient's heart
chamber to be partitioned.
3. The device of claim 1 wherein the pressure receiving surface of
the partitioning component is formed at least in part of a
membrane.
4. The device of claim 3 wherein the membrane is foraminous.
5. The device of claim 3 wherein the membrane is formed at least in
part of a polymeric fabric.
6. The device of claim 5 wherein the polymeric fabric of the
membrane is secured to the ribs by polymeric material fused in the
polymeric fabric.
7. The device of claim 6 wherein the distal ends of the ribs are
configured to facilitate abduction of the free proximal ends of the
ribs away from a centerline axis to facilitate expansion of the
reinforced partitioning component.
8. The device of claim 6 wherein the free proximal ends of the ribs
are outwardly curved.
9. The device of claim 8 wherein the free proximal ends of the ribs
have tips which penetrate the tissue lining the heart chamber at an
angle of not more than 30.degree. away from a line perpendicular to
the center line axis of the partitioning device.
10. The device of claim 1 wherein the pressure receiving surface
has radial dimensions from a center line axis of about 10 to about
160 mm.
11. The device of claim 1 wherein the pressure receiving surface
has radial dimensions from a center line axis of about 5 to about
80 mm.
12. The device of claim 1 wherein the frame has about 3 to about 30
ribs.
13. The device of claim 1 wherein the frame has about 6 to about 16
ribs.
14. The device of claim 1 wherein the expandable frame is self
expanding.
15. The device of claim 1 wherein the frame is formed of
superelastic NiTi, alloy which is in an austenite phase when
unstressed.
16. The device of claim 1 wherein the frame is in a stress
maintained martensite phase when delivered through the patient's
vasculature to the patient's heart chamber.
17. The device of claim 3 wherein the membrane is formed at least
in part of expanded fluoropolymer.
18. The device of claim 17 wherein the expanded fluoropolymer is
polytetrafluoroethylene.
19. A partitioning apparatus for a patients heart chamber to
Improve cardiac ejection fraction, comprising: a. a central hub
component; b. an expandable frame component having a plurality of
ribs with free, outwardly flared proximal ends and distal ends
secured to the central hub component; c. a membrane component
secured to the expandable frame ribs which defines a recessed,
pressure receiving surface; and d. tissue penetrating tips on a
plurality of free, outwardly flared proximal ends which are
configured to penetrate tissue lining the heart chamber to be
partitioned at an angle essentially perpendicular to a center line
axis of the partitioning device.
20. The partitioning apparatus of claim 30 wherein the hub has a
non-traumatic distal tip to engage the region of the patients
ventricular wall.
21. The partitioning apparatus of claim 30 wherein the
non-traumatic distal tip has a bullet shape.
22. The partitioning apparatus of claim 30 wherein the membrane
component is secured to the proximal side of the ribs.
23. The partitioning apparatus of claim 30 wherein the membrane
component is secured to the distal side of the ribs.
24. An intracorporeal delivery catheter for a ventricular
partitioning device for treating a patient with CHF, comprising: a.
an elongated shaft which has proximal and distal ends, a port
proximal to the distal end and an inner lumen In fluid
communication with the port; b. a releasable securing element on
the distal end of the elongated shaft configured to secure and
release a ventricular partitioning device; and c. an inflatable
member on a distal portion of the elongated shaft having an
interior in fluid communication with the inner lumen in the
elongated shaft through the port therein which Is configured to
expand a reinforced membrane of the partitioning device.
25. The intracorporeal delivery catheter of claim 24 wherein the
elongated shaft has an outer shaft member with an inner lumen and
an inner shaft member disposed within the inner lumen of the outer
shaft, which has proximal and distal end, which has a first inner
lumen extending within the inner shaft to the port proximal to the
distal end of the inner shaft member to provide inflation fluid to
the interior of the inflatable member, which has a second port in
the distal end thereof and a second inner lumen extending within
the inner shaft to the port in the distal end thereof.
26. The intracorporeal delivery catheter of claim 25 including a
torque shaft which has proximal and distal ends, which is rotatably
disposed within the second inner lumen of the inner shaft member
and which has the releasable securing element on the distal end
thereof for securing and releasing a ventricular partitioning
device.
27. The intracorporeal delivery catheter of claim 26 wherein the
releasable securing element on the distal end of the torque shaft
is a helical screw connection element.
28. The intracorporeal delivery catheter of claim 27 wherein the
helical screw connection element on the distal end of the torque
shaft is configured to engage a connector bar on the partitioning
device.
29. An intracorporeal delivery catheter for a ventricular
partitioning device for treating a patient with CHF, comprising: a.
an elongated outer shaft with an inner lumen; b. an inner shaft
which is disposed within the inner lumen of the outer shaft, which
has a first inner lumen extending within the inner shaft to a port
proximal to the distal end thereof, which has a second inner lumen
extending within the inner shaft to the distal end thereof; a
balloon mounted on a distal portion of the inner shaft having an
interior in fluid communication with the first inner lumen through
the port; c. a torque shaft which has proximal and distal ends,
which is rotatably disposed within the second inner lumen of the
inner shaft, which has a screw connection element on the distal end
thereof extending out of the distal end of the inner shaft and
configured to receive a partitioning device; and d. an inflation
port in fluid communication with the first inner lumen of the inner
shaft for delivery of inflation fluid therethrough to the interior
of the balloon.
30. An Intracorporeal partitioning component comprising: a. a frame
having a plurality of ribs with radially extending proximal ends
and with distal ends secured to a hub; and b. at least one porous
sheet material secured to the ribs of the frame by fused
thermoplastic material within the porous sheet material.
31. The intracorporeal partitioning component of claim 30 wherein
at least one porous sheet is secured to the upper portion of the
ribs of the frame and at least one sheet is secured to the lower
portion of the ribs of the frame by thermoplastic material within
the porous sheets.
32. A method of securing a porous polymeric sheet material to rib
components of a frame structure, comprising: a. sliding a
thermoplastic tube over one or more rib components of the frame; b.
applying a porous sheet to the ribs covered with the thermoplastic
polymeric tubes to form an assembly; and c. heating the assembly to
fuse the polymeric material of the thermoplastic tubes within the
porous sheet.
33. The method of claim 32 wherein a porous sheet is applied to the
upper surface of the frame.
34. The method of claim 32 wherein a porous sheet is applied to the
lower surface of the frame.
35. The method of claim 32 wherein a first porous sheet is applied
to the upper surface of the frame and a second porous sheet is
applied to the lower surface of the frame.
36. The method of claim 35 wherein the assembly is placed onto a
receiving platen of a press and a hot pressing platen is pressed
against the assembly to fuse the thermoplastic polymeric material
on the ribs of the frame within one or both of the porous
membranes.
37. A method of treating a patient with congestive heart failure by
partitioning the patient's heart chamber, comprising: a. providing
a reinforced membrane having a first contracted configuration for
delivery to the patient's heart chamber and a second expanded
configuration for deployment within the patient's heart chamber; b.
advancing the reinforced membrane in the first contracted
configuration into the chamber of the patient's heart; c. inflating
an inflatable member disposed within the membrane to expand the
reinforced membrane to the second expanded configuration to
facilitate securing the reinforced membrane within the patient's
heart chamber to partition the chamber into a primary productive
portion and a secondary non-productive portion.
38. The method of claim 37 wherein the reinforced membrane is
advanced into the patient's heart chamber through an inner lumen of
a delivery catheter.
39. The method of claim 38 wherein the inflatable member is
positioned on a distal portion of the delivery catheter.
40. The method of claim 37 wherein the expanding inflatable member
secures a peripheral edge of the reinforced membrane to a wall
defining at least in part the patients heart chamber.
41. The method of claim 37 wherein a central portion of the
expanded reinforced membrane is spaced from a wall defining in part
the patients heart chamber.
42. The method of claim 38 wherein the reinforced membrane is
positioned within an inner lumen of the delivery catheter in the
first contracted configuration, and advanced therein to a discharge
port in the distal end of the delivery catheter and discharged from
the discharge port into the patient's heart chamber where the
contracted reinforced membrane expands to the second expanded
configuration due at least in part to the expanding inflatable
member.
43. The method of claim 38 wherein the delivery catheter is
percutaneously introduced into the patient's vasculature and
advanced therein until the distal end of the delivery catheter is
disposed within the patients heart chamber.
44. The method of claim 40 wherein the edge of the reinforced
membrane is secured to a wall defining at least in part the heart
chamber by anchoring elements provided on the edge of the
reinforced membrane.
45. The method of claim 37 wherein the reinforced membrane is in
part self expanding.
46. A method of treating a patient with congestive heart failure,
comprising: a. providing an expandable reinforced membrane having a
periphery with a plurality of anchoring elements thereon; b.
advancing the reinforced membrane in a contracted configuration
within the patients vasculature until the reinforced member is
disposed within a chamber of the patient's heart; and c. inflating
a balloon within the contracted reinforced membranes to expand the
reinforced membrane into an expanded configuration within the heart
chamber to secure the periphery of the reinforced membrane to the
heart wall by the anchoring elements on the periphery of the
reinforced membrane.
47. A method of treating a patient with congestive heart failure,
comprising the steps of: a. providing an expandable reinforced
membrane having a periphery with a plurality of anchoring elements
thereon; b. advancing the reinforced membrane in a contracted
configuration within the patient's vasculature until the reinforced
member is disposed within a chamber of the patient's heart; and c.
inflating a balloon within the contracted reinforced membranes to
expand the reinforced membrane into an expanded configuration
within the heart chamber to secure the periphery of the reinforced
membrane to the heart wall by the anchoring elements on the
periphery of the reinforced membrane.
48. An intracorporeal product comprising: a. a first component
configured for intracorporeal deployment; and b. at least one sheet
of ePTFE material secured to the first component by fused
thermoplastic material therebetween.
49. The intracorporeal product of claim 30 wherein a second ePTFE
sheet is secured to the first component by thermoplastic material
within the porous sheets.
50. A method of making an intracorporeal product securing a porous
polymeric sheet material to rib components of a frame structure,
comprising: a. providing a ePTFE sheet; b. providing an
intracorporeal component; c. deploying a thermoplastic element over
at least part of the intracorporeal component; d. applying the
ePTFE sheet to at least a portion of the intracorporeal component
covered by the at least one thermoplastic element to form an
assembly; and e. heating the assembly to fuse the thermoplastic
material and secure the ePTFE sheet to the intracorporeal
component.
51. The method of claim 50 wherein the ePTFE sheet is applied to an
upper surface of the intracorporeal component.
52. The method of claim 50 wherein the ePTFE sheet is applied to a
lower surface of the intracorporeal component.
53. The method of claim 51 wherein a second ePTFE sheet is applied
to the lower surface of the intrecorporeal component.
54. The method of claim 50 wherein pressure is applied to the
assembly at elevated temperature to fuse the thermoplastic
polymeric material and secure the ePTFE sheet to the intracorporeal
component.
Description
FIELD OF THE INVENTION
[0001] The present invention relates generally to the field of
treating congestive heart failure and more specifically, to a
device and method for partitioning a patient's heart chamber and a
system for delivering the treatment device.
BACKGROUND OF THE INVENTION
[0002] Congestive heart failure (CHF) is characterized by a
progressive enlargement of the heart, particularly the left
ventricle and is a major cause of death and disability in the
United States. Approximately 500,000 cases occur annually in the
U.S. alone. As the patient's heart enlarges, it cannot efficiently
pump blood forward with each heart beat. In time, the heart becomes
so enlarged the heart cannot adequately supply blood to the body.
Even in healthy hearts only a certain percentage of the blood in a
patient's left ventricle is pumped out or ejected from the chamber
during each stroke of the heart. The pumped percentage, commonly
referred to as the "ejection fraction", is typically about sixty
percent for a healthy heart. A patient with congestive heart
failure can have an ejection fraction of less than 40% and
sometimes lower. As a result of the low ejection fraction, a
patient with congestive heart failure is fatigued, unable to
perform even simple tasks requiring exertion and experiences pain
and discomfort. Further, as the heart enlarges, the internal heart
valves such as the mitral valve, cannot adequately close. An
incompetent mitral valve allows regurgitation of blood from the
left ventricle back into the left atrium, further reducing the
heart's ability to pump blood forewardly.
[0003] Congestive heart failure can result from a variety of
conditions, including viral infections, incompetent heart valves
(e.g. mitral valve), ischemic conditions in the heart wall or a
combination of these conditions. Prolonged ischemia and occlusion
of coronary arteries can result in myocardial tissue in the
ventricular wall dying and becoming scar tissue. Once the
myocardial tissue dies, it is less contractile (sometimes
non-contractile) and no longer contributes to the pumping action of
the heart. It is referred to as hypokinetic. As the disease
progresses, a local area of compromised myocardium may bulge out
during the heart contractions, further decreasing the heart's
ability to pump blood and further reducing the ejection fraction.
In this instance, the heart wall is referred to as dyskinetic or
akinetic. The dyskinetic region of the heart wall may stretch and
eventually form an aneurysmic bulge.
[0004] Patients suffering from congestive heart failure are
commonly grouped into four classes, Classes I, II, III and IV. In
the early stages, Classes I and II, drug therapy is presently the
most commonly prescribed treatment. Drug therapy typically treats
the symptoms of the disease and may slow the progression of the
disease, but it can not cure the disease. Presently, the only
permanent treatment for congestive heart disease is heart
transplantation, but heart transplant procedures are very risky,
extremely invasive and expensive and are performed on a small
percentage of patients. Many patient's do not qualify for heart
transplant for failure to meet any one of a number of qualifying
criteria, and, furthermore, there are not enough hearts available
for transplant to meet the needs of CHF patients who do
qualify.
[0005] Substantial effort has been made to find alternative
treatments for congestive heart disease. For example, surgical
procedures have been developed to dissect and remove weakened
portions of the ventricular wall in order to reduce heart volume.
This procedure is highly invasive, risky and expensive and is
commonly only done in conjunction with other procedures (such as
heart valve replacement or coronary artery by-pass graft).
Additionally, the surgical treatment is usually limited to Class IV
patients and, accordingly, is not an option for patients facing
ineffective drug treatment prior to Class IV. Finally, if the
procedure fails, emergency heart transplant is the only presently
available option.
[0006] Other efforts to treat CHF include the use of an elastic
support, such as an artificial elastic sock placed around the heart
to prevent further deleterious remodeling.
[0007] Additionally, mechanical assist devices have been developed
as intermediate procedures for treating congestive heart disease.
Such devices include left ventricular assist devices and total
artificial hearts. A left ventricular assist device includes a
mechanical pump for increasing blood flow from the left ventricle
into the aorta. Total artificial heart devices, such as the Jarvik
heart, are usually used only as temporary measures while a patient
awaits a donor heart for transplant.
[0008] Recently, improvements have been made in treating patient's
with CHF by implanting pacing leads in both sides of the heart in
order to coordinate the contraction of both ventricles of the
heart. This technique has been shown to improve hemodynamic
performance and can result in increased ejection fraction from the
right ventricle to the patient's lungs and the ejection fraction
from the left ventricle to the patient's aorta. While this
procedure has been found to be successful in providing some relief
from CHF symtoms and slowed the progression of the disease, it has
not been able to stop the disease.
SUMMARY OF THE INVENTION
[0009] The present invention is directed to a ventricular
partitioning device and method of employing the device in the
treatment of a patient with congestive heart failure (CHF).
Specifically, the device partitions a chamber of the patient's
heart into a main productive portion and a secondary non-productive
portion. This partitioning reduces the total volume of the heart
chamber, reduces the stress applied to the heart and, as a result,
improves the ejection fraction thereof.
[0010] A partitioning device embodying features of the invention
has a reinforced partitioning component with a concave, pressure
receiving surface which defines in part the main productive portion
of the partitioned heart chamber when secured within the patient's
heart chamber.
[0011] The reinforced partitioning component preferably includes a
hub and a membrane forming the pressure receiving surface. The
partitioning component is reinforced by a radially expandable frame
component formed of a plurality of ribs.
[0012] The ribs of the expandable frame have distal ends secured to
the central hub and free proximal ends. The distal ends are
preferably secured to the central hub to facilitate radial self
expansion of the free proximal ends of the ribs away from a
centerline axis. The distal ends of the ribs may be pivotally
mounted to the hub and biased outwardly or fixed to the hub and
formed of material such as superelastic NiTi alloy which allows for
compressing the free proximal ends of the ribs toward a centerline
axis into a contracted configuration and when released allow for
their self expansion to an expanded configuration.
[0013] The free proximal ends of the ribs are configured to engage
and preferably penetrate the tissue lining the heart chamber to be
partitioned so as to secure the peripheral edge of the partitioning
component to the heart wall and fix the partitioning component
within the chamber so as to partition the chamber in a desired
manner. The tissue penetrating proximal tips are configured to
penetrate the tissue lining at an angle approximately perpendicular
to a center line axis of the partitioning device. The tissue
penetrating proximal tips of the ribs may be provided with barbs,
hooks and the like which prevent withdrawal from the tips from the
heart wall.
[0014] The ribs in their expanded configuration angle outwardly
from the hub and the free proximal ends curve outwardly so that the
membrane secured to the ribs of the expanded frame forms a
trumpet-shaped, pressure receiving surface.
[0015] The partitioning membrane in the expanded configuration has
radial dimensions from about 10 to about 160 mm, preferably about
50 to about 100 mm, as measured from the center line axis.
[0016] The partitioning device may be delivered percutaneously or
intraoperatively. One particularly suitable delivery catheter has
an elongated shaft, a releasable securing device on the distal end
of the shaft for holding the partitioning device on the distal end
and an expandable member such as an inflatable balloon on a distal
portion of the shaft proximal to the distal end to press the
interior of the recess formed by the pressure receiving surface to
ensure that the tissue penetrating tips or elements on the
periphery of the partitioning device penetrate sufficiently into
the heart wall to hold the partitioning device in a desired
position to effectively partition the heart chamber.
[0017] The partitioning device embodying features of the invention
is relatively easy to install and it substantially improves the
pumping action of the heart and provides an increase in the
ejection fraction of the patient's heart chamber. These and other
advantages of the invention will become more apparent from the
following detailed description of the invention and the
accompanying exemplary drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] FIG. 1 is an elevational view of a partitioning device
embodying features of the invention in an expanded
configuration.
[0019] FIG. 2 is a plan view of the partitioning device shown in
FIG. 1.
[0020] FIG. 3 is a partial longitudinal cross-sectional view of the
hub of the partitioning device shown in FIG. 1.
[0021] FIG. 4 is a transverse cross sectional view of the hub shown
in FIG. 3 taken along the lines 4-4.
[0022] FIG. 5 is a schematic elevational view of a delivery system
for the partitioning device shown in FIGS. 1 and 2.
[0023] FIG. 6 is a transverse cross-sectional view of the delivery
system shown in FIG. 5 taken along the lines 6-6.
[0024] FIG. 7 is an elevational view, partially in section, of the
hub shown in FIG. 3 secured to the helical coil of the delivery
system shown in FIG. 5.
[0025] FIGS. 8A-8E are schematic views of a patient's left
ventricular chamber illustrating the deployment of the partitioning
device shown in FIGS. 1 and 2 with the delivery system shown in
FIG. 5 to partition the heart chamber into a primary productive
portion and a secondary, non-productive portion.
[0026] FIG. 9 is a partial schematic view of the expandable frame
of the partitioning device shown in FIGS. 1 and 2 in an
unrestricted configuration.
[0027] FIG. 10 is a top view of the expandable frame shown in FIG.
9.
[0028] FIGS. 11-13 are schematic illustrations of a method of
forming the partitioning device shown in FIGS. 1 and 2 from the
expandable frame shown in FIGS. 9 and 10.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0029] FIGS. 1-4 illustrate a partitioning component 10 which
embodies features of the invention and which includes a
partitioning membrane 11, a hub 12, preferably centrally located on
the partitioning device, and a radially expandable reinforcing
frame 13 formed of a plurality of ribs 14. Preferably, the
partitioning membrane 11 is secured to the proximal or pressure
side of the frame 13 as shown in FIG. 1. The ribs 14 have distal
ends 15 which are secured to the hub 12 and free proximal ends 16
which are configured to curve or flare away from a center line axis
17. Radial expansion of the free proximal ends 16 unfurls the
membrane 11 secured to the frame 13 so that the membrane presents a
relatively smooth, pressure receiving surface 18 which defines in
part the productive portion of the patient's partitioned heart
chamber.
[0030] As shown in more detail in FIGS. 3 and 4, the distal ends 15
of the ribs 14 are secured within the hub 12 and a transversely
disposed connector bar 20 is secured within the hub which is
configured to secure the hub 12 and thus the partitioning component
10 to a delivery system such as shown in FIG. 5 and 6. The curved
free proximal ends 16 of ribs 14 are provided with sharp tip
elements 21 which are configured to hold the frame 13 and the
membrane 11 secured thereto in a deployed position within the
patient's heart chamber. Preferably, the sharp tip elements 21 of
the frame 13 penetrate into tissue of the patient's heart wall in
order to secure the partitioning component 10 within the heart
chamber so as to partition the ventricular chamber into a
productive portion and a non-productive portion.
[0031] The connector bar 20 of the hub 12, as will be described
later, allows the partitioning device 10 to be secured to a
delivery system delivery and to be released from the delivery
system within the patient's heart chamber. The distal ends 15 of
the reinforcing ribs 14 are secured within the hub 12 in a suitable
manner or they may be secured to the surface defining the inner
lumen or they may be disposed within channels or bores in the wall
of the hub 12. The ribs 14 are preshaped so that when not
constrained other than by the membrane 11 secured thereto (as shown
in FIGS. 1 and 2), the free proximal ends 16 thereof expand to a
desired angular displacement away from a center line axis 17 which
is about 20.degree. to about 90.degree., preferably about
50.degree. to about 80.degree..
[0032] FIGS. 5-7 illustrate a suitable delivery system 30
delivering the partitioning component 10 shown in FIGS. 1 and 2
into a patient's heart chamber and deploying the partitioning
component 10 to partition the heart chamber as shown in FIGS.
8A-8E. The delivery system 30 includes a guide catheter 31 and a
delivery catheter 32.
[0033] The guide catheter has an inner lumen 33 extending between
the proximal end 34 and distal end 35. A hemostatic valve (not
shown) may be provided at the proximal end 34 of the guide catheter
31. A flush port 36 on the proximal end 34 of guide catheter 31 is
in fluid communication with the inner lumen 33.
[0034] The delivery catheter 32 has an outer shaft 40 with an inner
lumen 41 and a proximal injection port 42, an inner shaft 43
disposed within the inner lumen 41 with a first lumen 44 and a
second lumen 45. Balloon inflation port 46 is in fluid
communication with the first lumen 44 and flush port 47 is in fluid
communication with the second lumen 45. Torque shaft 48 is
rotatably disposed within the second lumen 44 of the inner shaft 43
and has an injection port 49 provided at its proximal end 50 in
fluid communication with the inner lumen 51 of the torque shaft.
The torque shaft 48 is preferably formed at least in part of a
hypotube formed of suitable material such as superelastic NITINOL
or stainless steel. A torque knob 52 is secured to the proximal end
50 of torque shaft 48 distal to the injection port 49. A helical
coil screw 53 is secured to the distal end 54 of the torque shaft
48 and rotation of the torque knob 52 on the proximal end 50 of the
torque shaft 48 rotates the screw 53 on the distal end 54 of torque
shaft 48 to facilitate deployment of a partitioning device 10. A
inflatable balloon 55 is sealingly secured to the distal end of the
inner shaft 43 and has an interior 56 in fluid communication with
the first lumen 44. Inflation fluid may be delivered to the
interior 56 through port 44a in the portion of the inner shaft 43
extending through the balloon 55. Inflation of the balloon 55 by
inflation fluid through port 57 facilitates securing the
partitioning component 10.
[0035] To deliver the partitioning component 10, it is secured to
the distal end of the delivery catheter 32 by means of the helical
coil screw 53. The partitioning component 10 is collapsed to a
first, delivery configuration which has small enough transverse
dimensions to be slidably advanced through the inner lumen 33 of
the guide catheter 31. Preferably, the guide catheter 31 has been
previously percutaneously introduced and advanced through the
patient's vasculature, such as the femoral artery, in a
conventional manner to the desired heart chamber. The delivery
catheter 32 with the partitioning component 10 attached is advanced
through the inner lumen 33 of the guide catheter 31 until the
partitioning component 10 is ready for deployment from the distal
end of the guide catheter 31 into the patient's heart chamber 58 to
be partitioned.
[0036] The partitioning component 10 mounted on the screw 53 is
urged partially out of the inner lumen 33 of the guide catheter 31
until the hub 12 engages the heart wall as shown in FIG. 8B with
the free proximal ends 16 of the ribs 14 in a contracted
configuration within the guide catheter. The guiding catheter 31 is
withdrawn while the delivery catheter 32 is held in place until the
proximal ends 16 of the ribs 14 exit the distal end 35 of the
guiding catheter. The free proximal ends 16 of ribs 14 expand
outwardly to press the sharp proximal tips 21 of the ribs 14
against and preferably into the tissue lining the heart chamber.
This is shown in FIG. 8C.
[0037] With the partitioning component deployed within the heart
chamber and preferably partially secured therein, inflation fluid
is introduced through the inflation port 46 into first lumen 44 of
inner shaft 43 of the delivery catheter 32 where it is directed
through port 44a into the balloon interior 56 to inflate the
balloon. The inflated balloon presses against the pressure
receiving surface 18 of the partitioning component 10 to ensure
that the sharp proximal tips 21 are pressed well into the tissue
lining the heart chamber.
[0038] With the partitioning device 10 properly positioned within
the heart chamber, the knob 52 on the torque shaft 48 is rotated
counter-clockwise to disengage the helical coil screw 53 of the
delivery catheter 32 from the hub 12. The counter-clockwise
rotation of the torque shaft 48 rotates the helical coil screw 53
which rides on the connector bar 20 secured within the hub 12. Once
the helical coil screw 53 disengages the connector bar 20, the
delivery system 30, including the guide catheter 31 and the
delivery catheter 32, may then be removed from the patient.
[0039] The proximal end of the guide catheter 31 is provided with
an flush port 36 to inject therapeutic or diagnostic fluids through
the inner lumen 33. Similarly, the proximal end of the delivery
catheter 32 is provided with a flush port 42 in communication with
inner lumen 41 for essentially the same purpose. An inflation port
46 is provided on the proximal portion of the delivery catheter for
delivery of inflation fluid through the first inner lumen 44 to the
interior 56 of the balloon 55. Flush port 47 is provided in fluid
communication with the second inner lumen 45 of the inner shaft 43.
An injection port 49 is provided on the proximal end of the torque
shaft 48 in fluid communication with the inner lumen 51 of the
torque shaft for delivery of a variety of fluids.
[0040] The partitioning component 10 partitions the patient's heart
chamber 57 into a main productive or operational portion 58 and a
secondary, essentially non-productive portion 59. The operational
portion 58 is much smaller than the original ventricular chamber 57
and provides for an improved ejection fraction. The partitioning
increases the ejection fraction and provides an improvement in
blood flow. Over time, the non-productive portion 59 fills first
with thrombus and subsequently with cellular growth. Bio-resorbable
fillers such as polylactic acid, polyglycolic acid,
polycaprolactone and copolymers and blends may be employed to
initially fill the non-productive portion 59. Fillers may be
suitably supplied in a suitable solvent such as DMSO. Other
materials which accelerate tissue growth or thrombus may be
deployed in the non-productive portion 59.
[0041] FIGS. 9 and 10 illustrate the reinforcing frame 13 in an
unstressed configuration and includes the ribs 14 and the hub 12.
The ribs 14 have a length L of about 1 to about 8 cm, preferably,
about 1.5 to about 4 cm for most left ventricle deployments. The
proximal ends 16 have a flared construction. To assist in properly
locating the device during advancement and placement thereof into a
patient's heart chamber, parts, e.g. the distal extremity, of one
or more of the ribs and/or the hub may be provided with markers at
desirable locations that provide enhanced visualization by eye, by
ultrasound, by X-ray, or other imaging or visualization means.
Radiopaque markers may be made with, for example, stainless steel,
platinum, gold, iridium, tantalum, tungsten, silver, rhodium,
nickel, bismuth, other radiopaque metals, alloys and oxides of
these metals.
[0042] The partitioning device 10 is conveniently formed by placing
a thermoplastic tube 60, e.g. polyethylene, over the ribs 14 of the
frame 13 as shown in FIG. 11 until the proximal ends 16 of the ribs
14 extend out the ends of the thermoplastic tubes as shown in FIG.
12. A first expanded PTFE sheet 61 of appropriate size is placed in
the female platen 62 of the press 63. The frame 13 with tubes 60
slidably disposed over the ribs 14 is placed in platen 62 on top of
the ePTFE sheet 61. The center portion of the sheet 61 may be
provided with an opening through which the hub 12 extends. A second
ePTFE sheet 64 is placed on top of the ribs 14 of frame 13 as shown
in FIG. 13. The male platen 65 is heated, preferably to about
500.degree. F., so that the thermoplastic tubes 60 disposed over
the ribs 14 fuse into the porous matrix of the ePTFE sheets 61 and
64. The fused thermoplastic material solidifies and secures the
sheets 61 and 64 to the ribs 14 and prevents their delamination
during use.
[0043] While porous ePTFE material is preferred, the membrane 11
may be formed of suitable biocompatitble polymeric material which
include Nylon, PET (polyethylene terephthalate) and polyesters such
as Hytrel. The membrane 11 is preferably foraminous in nature to
facilitate tissue ingrowth after deployment within the patient's
heart. The delivery catheter 32 and the guiding catheter 31 may be
formed of suitable high strength polymeric material such as PEEK
(polyetheretherketone), polycarbonate, PET, Nylon, and the like.
Braided composite shafts may also be employed.
[0044] To the extent not otherwise described herein, the various
components of the partitioning device and delivery system may be
formed of conventional materials and in a conventional manner as
will be appreciated by those skilled in the art.
[0045] While particular forms of the invention have been
illustrated and described herein, it will be apparent that various
modifications and improvements can be made to the invention.
Moreover, individual features of embodiments of the invention may
be shown in some drawings and not in others, but those skilled in
the art will recognize that individual features of one embodiment
of the invention can be combined with any or all the features of
another embodiment. Accordingly, it is not intended that the
invention be limited to the specific embodiments illustrated. It is
intended that this invention to be defined by the scope of the
appended claims as broadly as the prior art will permit.
[0046] Terms such a "element", "member", "device", "section",
"portion", "step", "means" and words of similar import, when used
herein shall not be construed as invoking the provisions of 35
U.S.C. .sctn.112(6) unless the following claims expressly use the
terms "means" followed by a particular function without specific
structure or "step" followed by a particular function without
specific action. Accordingly, it is not intended that the invention
be limited, except as by the appended claims. All patents and
patent applications referred to above are hereby incorporated by
reference in their entirety.
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