U.S. patent application number 11/611658 was filed with the patent office on 2007-07-05 for method and apparatus for improved medical device profile.
This patent application is currently assigned to Cardiac Pacemakers, Inc.. Invention is credited to Benjamin R. Fruland, Robert S. Harguth, Keith R. Maile, Michael J. Root, Nick A. Youker.
Application Number | 20070156197 11/611658 |
Document ID | / |
Family ID | 38225532 |
Filed Date | 2007-07-05 |
United States Patent
Application |
20070156197 |
Kind Code |
A1 |
Root; Michael J. ; et
al. |
July 5, 2007 |
METHOD AND APPARATUS FOR IMPROVED MEDICAL DEVICE PROFILE
Abstract
The present subject matter includes an apparatus for positioning
in an implant site which includes a hermetically sealed shell
having an exterior shaped as a function of hydrodynamic drag at the
implant site, turbulence at the implant site, fluid sheer stress at
the implant site, and stagnation at the implant site; electronics
disposed in the hermetically sealed shell and a power source
disposed in the hermetically sealed shell.
Inventors: |
Root; Michael J.; (Lino
Lakes, MN) ; Youker; Nick A.; (River Falls, WI)
; Fruland; Benjamin R.; (Plymouth, MN) ; Maile;
Keith R.; (New Brighton, MN) ; Harguth; Robert
S.; (Ham Lake, MN) |
Correspondence
Address: |
SCHWEGMAN, LUNDBERG, WOESSNER & KLUTH, P.A.
P.O. BOX 2938
MINNEAPOLIS
MN
55402
US
|
Assignee: |
Cardiac Pacemakers, Inc.
4100 Hamline Avenue North
St. Paul
MN
55112-5798
|
Family ID: |
38225532 |
Appl. No.: |
11/611658 |
Filed: |
December 15, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60750517 |
Dec 15, 2005 |
|
|
|
Current U.S.
Class: |
607/36 |
Current CPC
Class: |
Y10T 29/49002 20150115;
A61N 1/37516 20170801; Y10T 29/49 20150115; A61N 1/37205 20130101;
A61N 1/37512 20170801; A61N 1/3756 20130101; A61N 1/37211 20130101;
A61N 1/375 20130101 |
Class at
Publication: |
607/036 |
International
Class: |
A61N 1/00 20060101
A61N001/00 |
Claims
1. An implantable device, comprising: an implantable electronics
shell; electronics disposed in the implantable electronics shell;
an implantable power source shell, the implantable power source
shell being hermetically sealed to the implantable electronics
shell with a first seal, with the electronics disposed outside the
implantable power source shell; and a power source disposed in the
implantable power source shell, the power source being sealed in
the implantable power source shell with a second seal, wherein an
exterior of the implantable device is defined in part by an
exterior of the implantable electronics shell and an exterior of
the implantable power source shell.
2. The implantable device of claim 1, wherein the power source is a
capacitor.
3. The implantable device of claim 1, wherein the electronics
include a pressure transducer.
4. The implantable device of claim 1, wherein the electronics
include cardiac rhythm management electronics.
5. The implantable device of claim 1, wherein the electronics
include neurostimulation electronics.
6. The implantable device of claim 1, wherein the electronics
include an ultrasonic transducer.
7. The implantable device of claim 1, wherein the power source
includes a battery.
8. The implantable device of claim 7, wherein the power source is a
primary battery.
9. The implantable device of claim 1, wherein the exterior of the
implantable device is approximately cylindrical.
10. The implantable device of claim 9, wherein the implantable
device defines a passage extending through the implantable
device.
11. The implantable device of claim 10, wherein the passage extends
through the first and implantable power source shells.
12. The implantable device of claim 1, wherein the first seal
includes a weld.
13. The implantable device of claim 12, wherein the second seal
includes a weld.
14. The implantable device of claim 1, wherein the implantable
electronics shell and the implantable power source shell are
approximately cylindrical.
15. The implantable device of claim 14, wherein a passage extends
through the implantable electronics shell and the implantable power
source shell.
16. A method for constructing a device for an implant site, the
method comprising: shaping an exterior of a hermetically sealed
shell, comprising: modeling the exterior to provide reduced
hydrodynamic drag in conditions measured at the implant site;
modeling the exterior to provide reduced turbulence in conditions
measured at the implant site; modeling the exterior to provide
reduced fluid sheer stress in conditions measured at the implant
site; and modeling the exterior to provide reduced stagnation in
conditions measured at the implant site.
17. The method of claim 16, further comprising: disposing a
transducer in the hermetically sealed shell; disposing a wireless
transmitter in the hermetically sealed shell; and disposing a power
source disposed in the hermetically sealed shell.
18. The method of claim 17, further comprising sensing pressure
with the transducer.
19. The method of claim 17, wherein the power source is a
battery.
20. The method of claim 19, wherein the battery is a primary
battery.
21. The method of claim 19, further comprising stacking into a
stack a plurality of substantially planar battery electrode layers
in a power source housing of the power source such that the profile
of the stack substantially conforms to an interior surface of the
hermetically sealed shell.
22. A system, comprising: an implantable medical device having a
handle, the implantable medical device including sensing
electronics and a power source; and a sensor positioning lead
having a clasp, the clasp being adapted to removably couple with
the handle.
23. The system of claim 22, further comprising a guide catheter,
wherein the implantable medical device is sized for passage through
the guide catheter and the sensor positioning lead is sized for
slidable disposition in the guide catheter.
24. The system of claim 22, wherein the handle includes a
cylindrical boss.
25. The system of claim 22, wherein the clasp includes a wire coil
adapted to removably coil around the handle.
26. The system of claim 22, wherein the clasp, in a first mode of
operation, is expanded to interference fit with an opening of the
implantable medical device, and in a second mode of operation, is
not interference fit with the opening.
27. The system of claim 26, further comprising a pushwire, which is
at least partially disposed through the opening in the first mode
of operation, and is not disposed through the opening in a second
mode of operation.
28. The system of claim 22, wherein the clasp includes claws
adapted to pinch the handle.
29. The system of claim 28, wherein the handle includes a ridge,
and the claws are shaped to mate to the ridge.
30. The system of claim 22, wherein the clasp includes a sleeve
interference fit around the handle.
31. The system of claim 30, further including a pushwire adapted to
push the handle out of the sleeve.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. 119(e)
of U.S. Provisional Patent Application Ser. No. 60/750,517, filed
Dec. 15, 2005, the entire disclosure of which is hereby
incorporated by reference in its entirety.
[0002] The following commonly assigned U.S. patent applications are
related and are all incorporated by reference in their entirety:
"Batteries Including a Flat Plate Design," U.S. Patent Publication
No. 2004/0127952, filed Feb. 7, 2003, "Batteries Including a Flat
Plate Design," U.S. Provisional Application Ser. No. 60/437,537
filed Dec. 31, 2002 and "System and Method for Sealing Battery
Separator," Ser. No. 11/264,996, filed Nov. 2, 2005.
TECHNICAL FIELD
[0003] This disclosure relates generally to implantable medical
devices, and more particularly to method and apparatus for improved
medical device profiles.
BACKGROUND
[0004] Batteries are available to provide energy for self-powered
devices. Various chemistries, construction methods, and battery
profiles have been developed for use in self-powered devices. But
as technology evolves, new applications would benefit from new
battery configurations. For example, known applications could
benefit from improvements in battery chemistries, constructions
methods, and battery profiles. Specifically, improved battery
profiles could enable improved device profiles, which could widen
the range of possible implantation locations. Such a range would
widen, in part, because improved shapes could address existing
problems, such as non-preferred levels of hemodynamic drag,
turbulence, fluid sheer stress and stagnation.
[0005] Improved batteries should provide as much electrical
performance as existing battery designs. Additionally, new designs
should be compatible with efficient manufacturing methods. Further,
new designs should offer a wide range of configurations to make
possible various applications.
SUMMARY
[0006] The above-mentioned problems and others not expressly
discussed herein are addressed by the present subject matter and
will be understood by reading and studying this specification.
[0007] One embodiment of the present subject matter includes an
implantable device which includes an implantable electronics shell
and an implantable power source shell wherein an exterior of the
implantable device is defined in part by an exterior of the
implantable electronics shell and an exterior of the implantable
power source shell.
[0008] Another embodiment of the present subject matter includes a
method for shaping a housing for an implantable device which
includes modeling the exterior to provide reduced hydrodynamic drag
in conditions measured at the implant site, modeling the exterior
to provide reduced turbulence in conditions measured at the implant
site, modeling the exterior to provide reduced fluid sheer stress
in conditions measured at the implant site and/or modeling the
exterior to provide reduced stagnation in conditions measured at
the implant site.
[0009] Yet another embodiment of the present subject matter
includes a system which includes an implantable medical device
having a handle and a positioning lead having a clasp adapted to
removably couple with the handle.
[0010] The present subject matter covers embodiments which include
power sources which are batteries. Some embodiments include power
sources which are capacitors. Various electronics are contemplated,
including cardiac rhythm management electronics, neurostimulation
electronics, wireless communications electronics, ultrasonic
transducer electronics, and others. The present subject matter
extends to embodiments which shape a shell, and dispose a
transducer, a wireless transmitter, and a power source in the
shell. The present subject matter extends to systems which include
implantable devices which are sized for passage through a guide
catheter, with sensor positioning leads sized for slidable
disposition in the guide catheter. Other features are contemplated
as well.
[0011] This Summary is an overview of some of the teachings of the
present application and not intended to be an exclusive or
exhaustive treatment of the present subject matter. Further details
about the present subject matter are found in the detailed
description and appended claims. Other aspects will be apparent to
persons skilled in the art upon reading and understanding the
following detailed description and viewing the drawings that form a
part thereof, each of which are not to be taken in a limiting
sense. The scope of the present invention is defined by the
appended claims and their legal equivalents.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 shows a schematic of an implantable medical device,
according to one embodiment of the present subject matter.
[0013] FIG. 2 shows a side view of an implantable medical device
having a semi-spherical shaped portion, according to one embodiment
of the present subject matter.
[0014] FIG. 3 shows a side view of an implantable medical device
having a polyhedral portion, according to one embodiment of the
present subject matter.
[0015] FIG. 4 shows a side view of an implantable medical device
having a polyhedral portion, according to one embodiment of the
present subject matter.
[0016] FIG. 5 shows a side view of an implantable medical device,
according to one embodiment of the present subject matter.
[0017] FIG. 6 shows a side view of an implantable medical device,
according to one embodiment of the present subject matter.
[0018] FIG. 7 shows a side view of an implantable medical device,
according to one embodiment of the present subject matter.
[0019] FIG. 8 shows a perspective view of an implantable medical
device, according to one embodiment of the present subject
matter.
[0020] FIG. 9 shows a cross section of an IMD deployment tool,
according to one embodiment of the present subject matter.
[0021] FIG. 10 shows a side view of an IMD, according to one
embodiment of the present subject matter.
[0022] FIG. 11 shows a partial cross section of an IMD deployment
system, according to one embodiment of the present subject
matter.
[0023] FIG. 12 shows a cross section of an IMD deployment tool,
according to one embodiment of the present subject matter.
[0024] FIG. 13A shows a side view of an IMD, according to one
embodiment of the present subject matter.
[0025] FIG. 13B shows a front view of an IMD, according to one
embodiment of the present subject matter.
[0026] FIG. 14 shows a partial cross section of an IMD deployment
system, according to one embodiment of the present subject
matter.
[0027] FIG. 15 shows a partial cross section of an implantable
medical device, according to one embodiment of the present subject
matter.
[0028] FIG. 16 shows a partial cross section of an implantable
medical device, according to one embodiment of the present subject
matter.
DETAILED DESCRIPTION
[0029] The following detailed description of the present subject
matter refers to subject matter in the accompanying drawings which
show, by way of illustration, specific aspects and embodiments in
which the present subject matter may be practiced. These
embodiments are described in sufficient detail to enable those
skilled in the art to practice the present subject matter.
References to "an", "one", or "various" embodiments in this
disclosure are not necessarily to the same embodiment, and such
references contemplate more than one embodiment. The following
detailed description is demonstrative and not to be taken in a
limiting sense. The scope of the present subject matter is defined
by the appended claims, along with the full scope of legal
equivalents to which such claims are entitled.
[0030] Various embodiments of the present subject matter include
implantable medical devices. In various embodiments, implantable
sensors are discussed. Implantable sensors, in various embodiments,
are self-powered measurement devices. In some embodiments, these
devices provide a wireless signal to one or more receivers.
Receivers may be located in vivo or ex vivo. A transceiver
relationship is additionally possible, in various embodiments, in
which bidirectional communications between a sensor and a receiver
are conducted.
[0031] Implantable sensors should be as compact as possible to
provide improved patient comfort and to ease the difficulties
facing care providers during the implantation procedure. An
implantation which is less invasive than prior designs is
preferred. As some embodiments are intended for endovascular use,
several design parameters are important. For example, to provide a
device which is compatible with some applications, it is important
to provide an implantable device which provides a reduced
hydrodynamic drag over existing designs. Some applications would
benefit from reduced turbulence. Some applications would benefit
from reduced fluid sheer stress. Some applications would benefit
from reduced stagnation. Applications which are not tuned in light
of one or more of these criteria can provide non-preferred
performance. Non-performing applications can pair with other risk
factors and lead to an embolus or another non-preferred
condition.
[0032] The present subject matter provides an implantable medical
device, in various embodiments, which features an improved profile
for implanted use. In some embodiments, the profile provides
improved performance for endovascular use.
[0033] FIG. 1 shows a schematic of an implantable medical device
100, according to one embodiment of the present subject matter.
Various embodiments of the present subject matter include
electronics 104. Additionally, in various embodiments, a power
source 102 is included. The implantable device 100 can be
symmetrical along three, two, or no axes, in various embodiments.
In various embodiments, the device includes a device shell 106. In
some of these embodiments, the device shell 106 is hermetically
sealed. In some embodiments, the device shell 106 is partially
defined by a case which houses electrodes for the power source 102.
A power source 102, in various embodiments, includes a battery. In
an additional embodiment, the power source 102 includes a
capacitor.
[0034] Electronics 104, in various embodiments, include various
components. Some embodiments include components adapted to
communicate energy with devices external to the implantable medical
device 100. In some of these embodiments, the energy is
communicated wirelessly. Embodiments within the present subject
matter include, but are not limited to, ultrasonic transducers,
inductive transducers, and other wireless transducers.
[0035] Additional components are included as well. Electronics 104
include, in various embodiments, components for wireless
communication of information to devices external to the implantable
medical device. Additionally, in various embodiments, electronics
104 include sensor electronics which communicate data. Some of
these embodiments include a pressure transducer. Also, in some
embodiments, electronics 104 include stimulation electronics. Some
of these embodiments include neurostimulation electronics. Some
embodiments include a processor interconnected to other components
to assist other components in communicating with each other. These
components are not an exhaustive or exclusive list of components
contemplated by the present subject matter, as the present subject
matter additionally extends to components not expressly listed
herein.
[0036] In various embodiments, the device shell includes a profile
which improves fluid flow. In some embodiments, the shell profile
reduces hydrodynamic drag, turbulence, fluid sheer stress, and/or
stagnation. In some embodiments, the shell is elongate. Some of
these embodiments include a shell which is elongate, and which
includes portions which have a circular cross section. An elongate
shell is useful for implantation in a blood vessel in a manner
which reduces hydrodynamic drag, turbulence, fluid sheer stress,
and/or stagnation. Various embodiments include applications which
have a profile adapted for implantation in a vein or in an artery.
Various embodiments use an elongate shell in which the power source
102 and electronics 104 are stacked in a column along the interior
of the elongate shell. In additional embodiments, the power source
102 and the electronics 104 are disposed side-by-side along the
length of the elongate shell.
[0037] In various embodiments, hydrodynamic drag, turbulence, fluid
sheer stress, and/or stagnation are determined using computational
fluid dynamics. In some embodiments, measurements are taken of a
target implant site. In some of these embodiments, the measurements
are used to determine the shape of an implantable medical device
which reduces hydrodynamic drag, turbulence, fluid sheer stress,
and/or stagnation.
[0038] Some embodiments do not base modeling for reduced
hydrodynamic drag, turbulence, fluid sheer stress, and/or
stagnation on the measurement of an individual implant site. In
some embodiments, the shape of the shell is determined based on
reduced hydrodynamic drag, turbulence, fluid sheer stress, and/or
stagnation in a statistically significant hypothetical model. For
example, in some embodiments, a patient population is measured, and
a model having blood-flow characteristics which typify the
population is created. This model is used in the creation of a
shell which reduces hydrodynamic drag, turbulence, fluid sheer
stress, and/or stagnation, in various embodiments.
[0039] In some of these embodiments, a power source 102 is created
to fill a portion of the interior of the implantable medical device
in a manner which limits the amount of unused space. In some of
these embodiments, the power source 102 is made from a stack of
substantially planar power source 102 electrodes. Some embodiments
use a stack of substantially planar power source 102 electrodes
having different layers perimeters. Such a stack can have contours
which are adapted to efficiently adhere to all or a portion of the
interior space of the implantable medical device. Additional
embodiments can use wound electrodes.
[0040] Battery embodiments having shapes which are determined as a
function of improved fluid flow also fall within the scope of the
present scope, including, but not limited to, battery embodiments
having a prismatic shape, a generally cylindrical shape, and other
shapes fall within the present scope.
[0041] In various embodiments, the implantable medical device 100
is adapted for reduced invasion during surgery. For example, in
some embodiments, a profiles is used which delivers reduced tissue
damage. Various embodiments include a profile having reduced tissue
damage includes an elongate device having a length of from about 5
millimeters to about 10 millimeters. Devices up to 5 millimeters
are possible, in various embodiments. Additional embodiments use
devices of over ten millimeters. Additionally, various embodiments
includes a profile which an average width of from about 1
millimeter to about 3 millimeters. Some embodiments are sized up to
1 millimeter. Additional embodiments are sized over 3 millimeters.
Various embodiments are cylindrical, and are from about 5 to 10
millimeters long, and about 1 to 3 millimeters in diameter. Some
embodiments are around 2.5 millimeters in diameter. Some
embodiments are greater than 3 millimeters in diameter.
Additionally, some embodiments are longer than 10 millimeters.
[0042] In some embodiments, the implantable medical device is
elongate, with a proximal portion and a distal portion. In various
embodiments, during implantation, the device is grasped at the
proximal portion, and the distal portion is led through
vasculature. In some of these embodiments, the distal portion has
one or more edges. Edges, in various embodiments, are rounded to
reduce tissue damage during implantation. Profiles which reduce
tissue damage may also be included. For example, implantable
medical devices having a parabolic distal portion fall within the
present scope. Some of these embodiments are bullet shaped. Other
profiles not expressly listed herein are additionally encompassed
by the present scope.
[0043] In one process of the present subject matter, a profile of
the implantable medical device 100 is determined as a function of
power and size requirements. Power requirements, in various
embodiments, are determined by the number of energy use events
which occur during implantation. In some embodiments around 33
milliamp-hours are consumed per month, for example. It is
understood that other devices using other power and size
requirements are contemplated to be within the scope of this
invention.
[0044] In some of these embodiments, power requirements are further
defined by battery efficiency. Battery efficiency, in various
embodiments, is a function of self-leakage. Power requirements are
further determined by battery type. For example, some embodiments
use primary batteries. Some embodiments use secondary batteries.
Secondary batteries enable recharging. Recharging, in various
embodiments, is depending on patient compliance. Recharging
frequency should be reduced to increase patient satisfaction.
[0045] In an additional process of the present subject matter, a
power requirement is determined and a power source 102 profile is
selected to satisfy the power requirement and to satisfy a size
requirement which reduces invasiveness. In some of these
embodiments, a power management algorithm is developed to comply
with these constraints. In some of these embodiments, a secondary
power source 102 is used. In some of these embodiments, a power
source 102 charging algorithm is used to improve power source 102
profile and the reduce requirements to a patient to visit a clinic
to recharge the power source 102. In various embodiments, an
iterative process of selecting a profile, and selecting a power
management algorithm is used to determine the final profile of
power source 102 which meets predetermined therapeutic
requirements.
[0046] Various embodiments incorporate battery chemistries
compatible with the present configurations. Embodiments within the
present scope include, but are not limited to, at least one of a
metal oxide, a metal sulfide, a metal selenide, a metal halide, a
metal oxyhalide compound, and corresponding lithiated forms. Some
of these embodiments include at least one of manganese, vanadium,
silver, molybdenum, tungsten, cobalt, nickel, chromium, and main
group compounds such as carbon monofluoride and iodine.
Additionally, some embodiments include at least one of carbon,
lithium, sodium, potassium, rubidium, cesium, magnesium, calcium,
strontium, barium, tin, zinc or silver.
[0047] Primary battery chemistry embodiments fall within the
present scope. Additionally, secondary battery chemistry
embodiments fall within the present scope. In some embodiments a
power source of an implantable medical device includes a plurality
of batteries connected in series, parallel or a combination of
series and parallel.
[0048] Various electrode constructions fall within the present
scope. Embodiments compatible with the present subject matter
include monolithic electrodes, pelleted electrodes, and other
electrodes which have a solid shape. Pelleted electrodes, in
various embodiments, include pellets formed from compressed powder,
dough or slurry. Some electrode embodiments are formed from a
tightly wound ribbon which is wound unto itself without an
insulator to separate progressive wraps from one another.
Additionally, some embodiment include an electrode onto which is
pressed or coated an electronically conductive material. Other
electrode configuration embodiments compatible with the present
subject matter additionally fall within the present scope.
[0049] Additionally, various battery profiles using these
electrodes fall within the present scope. Embodiments with the
present scope include, but are not limited to, batteries having a
cylindrical shape, batteries having a prismatic shape, batteries
having a button shape, and batteries having other shapes. In some
examples, batteries have shape which is determined as a function of
the shape's impact on reducing blood flow. In some examples,
batteries have shape which is determined as a function of the
shape's impact on reducing tissue damage during implantation.
[0050] FIG. 2 shows a side view of an implantable medical device
having a semi-spherical shaped portion, according to one embodiment
of the present subject matter. In various embodiments, a protrusion
202 extends from the main portion 204 of the implantable device.
The protrusion 202 is useful, in various embodiments, for
positioning the device in a target implant site. For example, in
some embodiments, a positioning lead grasps the device at
protrusion 202. Protrusion 202 includes a texture, in various
embodiments. For example, some embodiments of protrusion 202
include knurling. In various embodiments, the positioning lead
positions the device while connected to the implantable device at
the protrusion 202. In various embodiments, the positioning lead
releases the implantable medical device. In various embodiments,
the protrusion 202 provides a handle which is compatible with a
clasp of a positioning lead, but in some embodiments, a protrusion
is not included, and a positioning lead grasps the main body of the
implantable medical device.
[0051] FIG. 3 shows a side view of an implantable medical device
having a polyhedral portion, according to one embodiment of the
present subject matter. The implantable medical device pictured
includes a protrusion 302, and a main portion 304. The main portion
304 is shaped like a polyhedron, in some embodiments. In additional
embodiments, it is cone shaped.
[0052] FIG. 4 shows a side view of an implantable medical device
having a polyhedral portion, according to one embodiment of the
present subject matter. The implantable medical device pictured
includes a protrusion 402, and a main portion 404. The pictured
embodiment has a chisel shape.
[0053] FIG. 5 shows a side view of an implantable medical device,
according to one embodiment of the present subject matter. The
implantable medical device pictured includes a protrusion 502, and
a main portion 504. In various embodiments, the implantable medical
device has a distal portion which is shaped like a cone with the
tip missing. In additional embodiments, the main portion 504 is a
polyhedron. In some embodiments, the main portion 504 is bullet
shaped.
[0054] The shapes described and pictured herein do not define an
exhaustive or an exclusive list of the possible shapes within the
present subject matter. Additional shapes fall within the present
scope. For example, additional shapes which reduce hydrodynamic
drag, turbulence, fluid sheer stress, and/or stagnation, fall
within the present scope.
[0055] In various embodiments, an implantable medical device
includes an improved shape enabled by the use of a battery which
includes stacked electrodes. In some of these embodiments, the
contour of the stack is non-linear, enabling the stack to occupy
space within an implantable medical device efficiently.
Additionally, in some embodiments, the battery is a coil.
[0056] FIG. 6 shows a side view of an implantable medical device,
according to one embodiment of the present subject matter. The
device 602 includes a first portion 604 which has a first profile
shaped as a function of hydrodynamic drag, turbulence, fluid sheer
stress, and/or stagnation. The device additionally includes a
second portion 606 which has a second profile shaped as a finction
of hydrodynamic drag, turbulence, fluid sheer stress, and
stagnation.
[0057] Blood flow is known to be bidirectional in a blood vessel.
Additionally, as the heart pumps blood, the rate of blood flow of
blood varies across a cross section of a blood vessel. Therefore,
improved medical device embodiments are designed to offer increased
performance in reducing hydrodynamic drag, turbulence, fluid sheer
stress, and/or stagnation. The present subject matter includes a
device having a first portion 604 which is shaped to offer improved
compatibility with blood flow direction 608, in various
embodiments. In some of these embodiments, the present subject
matter includes a second portion 606 which is shaped to offer
improved compatibility with blood flow direction 610. Blood flow
direction 608 is approximately collinear with blood flow direction
610, in various embodiments.
[0058] FIG. 7 shows a side view of an implantable medical device,
according to one embodiment of the present subject matter. In
various embodiments, the device includes a first shell portion 703.
In additional embodiments, a second shell portion 705 is attached
to the first shell portion 703. The first shell portion 703 and the
second shell portion 705 are hermetically sealed to one another
with a hermetic seal 704, in various embodiments. Hermetic seals
include welds, resins, and additional types of known hermetic
seals.
[0059] In various embodiments, the first shell portion 702 doubles
as a case for a battery. For example, in some embodiments, a
battery anode and cathode are disposed in a case 702. Battery case
embodiments include a drawn case portion mated to another case
portion, in some examples. In some of these examples, a drawn case
portion is sealed to another case portion with a battery case seal.
In embodiments where the implantable medical device 701 requires a
hermetically sealed exterior, and the battery case seal is exposed
to the environment of the implantable medical device, the battery
case seal is hermetic. In embodiments where the battery case seal
is not exposed to the environment, the battery case seal may not be
hermetic. For example, in some non-hermetic embodiments, the
battery case seal is adapted to resist the flow of battery
electrolyte.
[0060] The implantable medical device 701, in various embodiments,
includes an optional cavity 710. In various embodiments, the cavity
passes through the implantable medical device 701. In additional
embodiments, the cavity does not pass through the implantable
medical device 701, but instead defines an interior cavity.
[0061] An optional cavity 710, in various embodiments, is defined
by a cylindrical opening which is concentric to an overall
cylindrical shape of the implantable medical device 701, in some
embodiments. Some configurations of the present subject matter are
toroidally shaped. Some shapes of the present subject matter
resemble an extruded toroid. In various embodiments, the cavity is
irregular.
[0062] FIG. 8 shows a perspective view of an implantable medical
device, according to one embodiment of the present subject matter.
In various embodiments, an implantable medical device 801 includes
a first portion 804 and a second portion 802. In some embodiments,
the second portion 802 includes electronics. Some of these
embodiments include pressure transducers. In additional
embodiments, the second portion 802 includes a battery. In some of
the embodiments, the battery is housed in the case which is the
same as the exterior of the second portion 802.
[0063] In some embodiments, the first portion 804 includes
electronics. Some of these embodiments include pressure
transducers. In additional embodiments, the first portion 804
includes a battery. In some of the embodiments, the battery is
housed in the case which is the same as the exterior of the first
portion 804.
[0064] In some embodiments, the first portion 804 extends through
the second portion 802. In some of these embodiments, a cavity
extends through the first portion 804. A cavity assists in
improving performance with respect to hydrodynamic drag at the
implant site, turbulence at the implant site, fluid sheer stress at
the implant site, and/or stagnation at the implant site. For
example, in some embodiments, a cavity discourages emboli
formation.
[0065] FIG. 9 shows a cross section of an IMD deployment tool,
according to one embodiment of the present subject matter. In
various embodiments, the present subject matter includes a
positioning lead for physical manipulation of an implantable
medical device. Implantable medical devices should be deployed in a
manner which reduced invasive damage. To this end, it is beneficial
to utilize techniques which employ catheters which can reduce
damage to patient tissues.
[0066] Catheter techniques are used in present embodiments which
enable the catheter to remain in place for a predetermined period
of time. For example, in one embodiment, a catheter is left in
place for approximately 30 minutes. In various embodiments, during
the time a catheter is in place, health care professionals are able
to position an implantable medical device. Additionally, an
implantable medical device may undergo a validation sequence to
ensure proper function, in various embodiments. If the implanted
device is improperly positioned, it may be adjusted while the
catheter is in place. If the implanted device does not pass
required validation criterion, it may be extracted and replaced
with a replacement device.
[0067] Various embodiments of the present subject matter include a
guide catheter 906. In various embodiments, the guide catheter 906
is implanted in the patient, with a proximal portion positioned
nearby a health care professional operating the catheter, and with
a distal portion positioned near a target implant site. A
positioning lead 903 is disposed through the guide catheter 906 in
various embodiments. In various embodiments, the positioning lead
903 is slidably disposed in the guide catheter 906.
[0068] In various embodiments, the positioning lead 903 includes a
clasp at a distal portion. In some of these embodiments, the clasp
includes claws 902A-N. In various embodiments, two claws are
included. In various embodiments, more than two claws are included.
Various embodiments include claws which are adapted to grasp, in
pairs, opposite sides of an object. In some embodiments, each claw
is equidistant from another. In additional embodiments, claws are
irregularly spaced while grasping an object. In one embodiment
having two claws, the claws are spaced at 180 degree intervals
around an implantable medical device. In an embodiment having four
claws, the claws are spaced at 90 degree intervals around an
implantable medical device. Claw configurations not expressly
listed herein also fall within the present scope. Claw material, in
various embodiments, includes nitinol, stainless steel, titanium,
and/or other materials. Other materials exist that are not
expressly listed herein and fall within the present scope.
[0069] The present subject matter includes claws which have
features 910A-N sized to receive a mating feature of an implantable
medical device. Some embodiments include features having a texture.
One texture includes knurling. Additional textures include ribbing.
This list is not exhaustive or exclusive, and additional features
and textures are possible without departing from the scope of the
present subject matter.
[0070] In various embodiments, an oversheath 904 is disposed over
the claws 902A-N. In various embodiments, the claws are formed
having a bias which encourages movement of the claws away from one
other but for a constraint nearby the claws. In some embodiments,
the oversheath provides such a constraint. In various embodiments,
when the oversheath is moved away from the grasping features of the
claws, the claws are able to move away from one another. Such
behavior, in various embodiments, provides for a mechanism with
which a grasped implantable medical device may be released. The
oversheath 904, in various embodiments, includes one or more of a
polyimide, TEFLON, PEBAX, and/or additional materials not listed
herein. TEFLON is a registered trademark of E. I. Du Pont de
Nemours and Company, 1007 Market St., Wilmington Del. 19898. PEBAX
is a registered trademark of Arkema Corporation France, 4-8 Cours
Michelet 92800, Puteaux France.
[0071] Additionally, some embodiments include a pushwire 908 which
may be used use push an implantable medical device away from the
claws 902A-N. A guidewire is also used, in some embodiments. In
various embodiments, the pushwire is biocompatible. In some
embodiments, the pushwire is metallic. Various embodiments include
MP35N, stainless steel, titanium, and/or additional metals, for
example. Some materials used include corrosion resistant alloys. In
additional embodiments, the pushwire is a nonmetallic material. One
embodiment includes TEFLON. TEFLON is a registered trademark of E.
I. Du Pont de Nemours and Company Corporation, 101 West 10.sup.th
St., Wilmington Del. 19898. Additional materials not expressly
listed herein are also within the present scope.
[0072] Various pushwire shapes are within the present subject
matter. Pushwire 908 functions to push an implantable medical
device away form the claws 902A-N, in various embodiments. In
additional embodiments, pushwire 908 functions to separate the
claws 902A-N such that a grasped implantable medical device is
released.
[0073] FIG. 10 shows a side view of an IMD, according to one
embodiment of the present subject matter. The implantable medical
device 1001, in various embodiments, includes electronics and a
power source. In some embodiments, the electronics include a
pressure transducer. In various embodiments, the implantable
medical device 1001 is hermetically sealed.
[0074] In various embodiments, the implantable medical device 1001
includes a ridge 1004. In various embodiments, the ridge is a rim.
In additional embodiments, the implantable medical device 1001
includes a protrusion which is shaped otherwise. For example, in
some embodiments, the protrusion is a boss. In some embodiments,
the protrusion is polyhedral. Additional features are used for
mating to grasping features of a positing tool. For example, some
embodiments have discrete pockets shaped to match features of a
clasp. The ridge, or additional features discussed herein, do not
comprise an exhaustive or exclusive list, and additional interface
designs are within the present scope.
[0075] In some of these embodiments, the ridge has a diameter which
is approximately the same as the internal diameter of a guide
catheter. For example, in one embodiment, a non-flexed guide
catheter has a lumen which is cylinder shaped, and which has a
diameter which is sized for passage an implantable medical
device.
[0076] FIG. 11 shows a partial cross section of an IMD deployment
system, according to one embodiment of the present subject matter.
The illustration shows one mode of operation, in which an
implantable medical device 1104 is grasped by a positioning lead
1102.
[0077] In various embodiments, a cavity is provided on an
implantable medical device. In some embodiments, a clasp is
collapsed with an oversheath. A collapsed clasp is inserted into a
cavity in various embodiments. Various embodiments release the
clasp into the cavity in order to secure the implantable medical
device to the clasp. In various embodiments, deployment of the
implantable medical device includes positioning the oversheath to
again collapse the clasp so that the clasp can be removed from the
cavity. In some embodiments, the cavity is located in the center of
a face of an implantable medical device. The locations set forth
herein are demonstrative and are not intended to be exclusive or
exhaustive. Additional locations fall within the present scope.
[0078] FIG. 12 shows a cross section of an IMD deployment tool,
according to one embodiment of the present subject matter. Various
embodiments of the present subject matter include a guide catheter
1206. In various embodiments, a positing tool 1201 is disposed in a
lumen of the guide catheter 1206. In various embodiments, the
positing tool 1201 includes a flexible sheath 1204. In various
embodiments, extending through the flexible sheath is a pushwire
1202. In some embodiments, the pushwire 1202 is slidably
interference fitted into the flexible sheath 1204. In various
embodiments, the flexible sheath 1204 is not interference fit to
the sheath 1204 once the pushwire 1202 is removed from the flexible
sheath 1204. Embodiments of the present subject matter include a
method of positioning the an implantable medical device. Some of
these embodiments include removing the pushwire 1202. Embodiments
include removing a sheath 1204 in which the pushwire is only
partially disposed. Some of these embodiments include removing a
sheath 1204 when the pushwire is sufficiently removed from the
lumen of the sheath such that the pushwire 1202 is not disposed
through an opening of the implantable medical device.
[0079] FIG. 13A shows a side view of an IMD, according to one
embodiment of the present subject matter. In various embodiments,
the implantable medical device 1302 includes an opening 1304. In
some embodiments, the opening is cylinder shaped. The opening 1304,
in various embodiments, provides access to opening 1306, in various
embodiments. FIG. 13B shows a front view of an IMD, according to
one embodiment of the present subject matter.
[0080] FIG. 14 shows a partial cross section of an IMD deployment
system, according to one embodiment of the present subject matter.
In various embodiments, the present system, in a deployment state,
disposes the guidewire through the flexible sheath in an area
proximal the opening 1404. The flexible sheath 1406, in various
embodiments, is moved from a state which is not interference fitted
to opening 1404, to a state which is interference fitted to opening
1404. As such, in the deployment state, the flexible sheath is
interference fitted with opening 1404, in various embodiments.
[0081] FIG. 15 shows a partial cross section of an implantable
medical device, according to one embodiment of the present subject
matter. Various embodiments of the present subject matter include
an implantable medical device 1502. Additionally included is a
protrusion 1510 of the implantable medical device. Various
embodiments additionally include a guide catheter 1508 as well.
[0082] The present subject matter, in various embodiments, includes
a sleeve 1504. In some embodiments, the sleeve is flexible. In
additional embodiments, the sleeve is a membrane. Various sleeve
1504 embodiments include PEBAX, silicone, SANTOPRENE, and/or
additional materials. SANTOPRENE is a registered trademark of
Advanced Elastomer Systems, L.P. Limited Partnership Assignee of
Delaware, 388 S. Main Street, Akron, Ohio 44311-1059. The sleeve
1504, in various embodiments, is interference fit to the protrusion
1510. In various embodiments, a push wire extends through a lumen
in sleeve 1504. In various embodiments, a health care professional
can pull the sleeve away form the implantable medical device 1502,
and out of contact with protrusion 1504, which pushing against
protrusion 1502 with the pushwire 1506. As such, a worker is able
to deploy the implantable medical device 1502 at an implant
site.
[0083] FIG. 16 shows a partial cross section of an implantable
medical device, according to one embodiment of the present subject
matter. Various embodiments of the present subject matter include
an implantable medical device 1602. Additionally included is a
protrusion 1514 of the implantable medical device. In some
embodiments, the protrusion 1514 includes a collar 1604. Additional
embodiments include features such as textures, depressions, or
additional features. For example, in some embodiments, a depression
rings the protrusion 1614.
[0084] Various embodiments additionally include a guide catheter
1612. Disposed through the guide catheter, in various embodiments,
is a positioning lead 1616. Positioning lead, in various
embodiments, includes a proximal portion, located external a
patient, and a distal portion. The distal portion of the
positioning lead 1616 is positioned proximal an implant site in
use, in various embodiments. In some embodiments, a substantially
coiled filament 1618 is wrapped around the protrusion 1614.
[0085] The coiled filament 1618, in some embodiments, extends along
the positioning lead 1616. In some embodiments, the coiled filament
1618 defines the exterior of the positing lead 1616. In some
embodiments, a positing lead includes a first portion which does
not include the coiled filament 1618, and which is connected to the
coiled filament 1618 at a distal portion of the positioning lead
1616. In some of these embodiments, the connection between the
first portion and the coiled filament 1618 includes a molded fit.
In some of these embodiments, the first portion is molded over the
coiled filament 1618.
[0086] In some embodiments, a coiled portion of the positioning
lead 1616, which includes portions adapted for wrapping around a
protrusion 1614, is disposed in a sheath 1608. A sheath can benefit
a positioning lead by providing a bias, by protecting a coiled
filament, and by providing a structure which has a lower instance
of axial compression than does a coiled filament.
[0087] In various embodiments, a push wire 1610 is disposed through
the positioning lead. The push wire 1610, in various embodiments,
is adapted for pushing the implantable medical device 1602, away
from the positioning lead 1616. In various embodiments, as the
implantable medical device 1602 is pushed away from the positioning
lead 1616, the coiled portions which are wrapped around a
protrusion unwrap. Such embodiments function to both position and
deploy the implantable medical device 1602.
[0088] This application is intended to cover adaptations or
variations of the present subject matter. It is to be understood
that the above description is intended to be illustrative, and not
restrictive. The scope of the present subject matter should be
determined with reference to the appended claims, along with the
full scope of equivalents to which such claims are entitled.
* * * * *