U.S. patent application number 13/122710 was filed with the patent office on 2012-09-27 for device, a kit and a method for heart support.
Invention is credited to Jan Otto Solem.
Application Number | 20120245679 13/122710 |
Document ID | / |
Family ID | 44673458 |
Filed Date | 2012-09-27 |
United States Patent
Application |
20120245679 |
Kind Code |
A1 |
Solem; Jan Otto |
September 27, 2012 |
Device, A Kit And A Method For Heart Support
Abstract
A device, a kit and a method is presented for permanently
augmenting the pump function of the left heart. The mitral valve
plane is assisted in a movement along the left ventricular long
axis during each heart cycle. The very close relationship between
the coronary sinus and the mitral valve is used by various
embodiments of a medical device providing this assisted movement.
By means of catheter technique an implant is inserted into the
coronary sinus, the device is augmenting the up and down movement
of the mitral valve and thereby increasing the left ventricular
diastolic filling when moving upwards and the piston effect of the
closed mitral valve when moving downwards.
Inventors: |
Solem; Jan Otto; (Bjarred,
SE) |
Family ID: |
44673458 |
Appl. No.: |
13/122710 |
Filed: |
March 25, 2011 |
PCT Filed: |
March 25, 2011 |
PCT NO: |
PCT/SE11/50337 |
371 Date: |
October 18, 2011 |
Current U.S.
Class: |
623/3.11 |
Current CPC
Class: |
A61M 1/1055 20140204;
A61M 1/1008 20140204; A61M 1/1068 20130101; A61H 31/004 20130101;
A61H 31/006 20130101; A61M 1/125 20140204; A61M 1/122 20140204;
A61F 2/2442 20130101; A61F 2/24 20130101; A61M 1/1049 20140204;
A61F 2/2451 20130101; A61M 1/10 20130101; A61M 1/12 20130101 |
Class at
Publication: |
623/3.11 |
International
Class: |
A61M 1/10 20060101
A61M001/10 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 25, 2011 |
SE |
SE1050282-1 |
Claims
1. A medical device for intra-cardiac blood circulation of a heart
of a patient comprising: a first anchor unit implantable in a
cardiac vessel of said heart in proximity to a mitral valve (MV), a
force generating unit in communication with said first anchor unit,
said force generating unit being operative to generate a force for
assisting said blood circulation according to a cardiac cycle of
said heart, and wherein said first anchor unit is configured to
receive said force in such a manner so as to cause movement of said
mitral valve in a mitral valve plane in a direction to and/or from
an apex of said heart.
2. The device of claim 1, wherein said movement extends
substantially along a long axis of the left ventricle of said
heart, and wherein said movement is provided during systole towards
an apex of said heart and/or during diastole away from said
apex.
3. The device of claim 2, wherein said movement is provided during
systole towards said apex of said heart and during diastole away
from said apex.
4. The device of claim 1, wherein said movement is provided along a
short axis of a left ventricle, transversal to said long axis so as
to thereby assist a natural inwards and outwards movement of a
lateral left ventricular wall relative to an intra-ventricular
septum.
5. The device of claim 1, wherein said force generating unit is
operatively connected to an external energy source to receive
energy therefrom and to controllably provide said movement in
synchrony with said cardiac cycle.
6. The device of claim 1, wherein said first anchor unit has an
expandable stent structure for anchoring said anchor unit in said
cardiac vessel.
7. The device of claim 1, wherein said first anchor unit has at
least one tissue anchoring element.
8. The device of claim 1, wherein said force generating unit is an
actuating unit for providing said force as a mechanical force, and
wherein said first anchor unit and said actuating unit are in
communication via a connecting unit for transferring said force and
providing said movement.
9. The device of claim 1, said device further comprising a second
anchor unit implantable in said cardiac vessel closer to an ostium
of a coronary sinus than said first anchor unit.
10. The device of claim 9, wherein said force generating unit is
comprised of an electrical motor integrated into said second anchor
unit and wherein said device further includes a connecting unit
between said motor and said first anchor.
11. The device of claim 9, wherein said second anchor unit has a
guiding unit for guiding said connecting unit from said first
anchor through said second anchor to an actuating unit.
12. The device of claim 9, wherein said device further comprises an
elongate extension unit connecting said first and second anchor
units in a loop shape, wherein said extension unit extends
proximally beyond said second anchor unit to a mechanical actuator
unit arranged to rotate said extension unit in one of first and
second direction, said first direction being where said loop shaped
extension unit is flexed towards the left atrium and said coronary
sinus (CS) and a great cardiac vein (GCV) and said mitral valve
(MV) is moved towards the left atrium, and said second direction
being opposite said first direction where said loop shaped
extension unit is flexed towards a left ventricular (LV) apex and
said CS and GCV and said MV is moved towards the LV apex.
13. The device of claim 1, wherein said force generating unit is a
magnetic unit for providing said force as a magnetically induced
force, and wherein said first anchor unit is magnetic, and wherein
said first anchor unit and said actuating unit are in magnetic
communication for transferring said force and providing said
movement.
14. The device of claim 13, wherein said first anchor unit and said
force generating unit are electromagnets, and wherein at least one
of said electromagnets is arranged to change polarity in synchrony
with said cardiac cycle.
15. The device of claim 1, wherein said force generating unit is
positionable in one of said heart, inside a side branch of the vein
system on a left ventricular wall of said heart, in the left
ventricle, in a right ventricle, in a right atrium, in a the left
atrium of said heart, on a left ventricular outer wall of said
heart.
16. The device of claim 1, wherein said first anchor unit is
positionable in one of the coronary sinus (CS), the great cardiac
vein (GCV), in a branch vessel thereof of said heart and said
device comprises a second anchor unit that is positionable in one
of said coronary sinus (CS), the great cardiac vein (GCV) and said
branch vessel thereof.
17. The device of claim 1, further comprising a remote energy
source, a control unit, and a sensor for measuring physiological
parameters related to the cardiac cycle and for generating a sensor
signal, wherein control unit controls said force generating unit to
provide said movement by energy from said remote energy source
based on said sensor signal.
18. The device of claim 17, wherein said remote energy source is
comprised of a mechanical section for generating at least one of a
rotational and linear motion, and an extension unit extending from
said mechanical section, wherein said mechanical section is said
force generating unit and wherein said motion is transferred in
operation of said mechanical section to said first anchor unit for
said movement of said mitral valve plane via an extension unit.
19. The device of claim 17, wherein said remote energy source is
controlled by said control unit to provide electrical energy to one
of at least one of an electromagnetical anchor unit affixed in
relation to said mitral valve or at least one force generating
unit.
20. The device of claim 1, wherein said force generating unit is a
resilient unit, and said first anchor unit includes a distal anchor
unit and a proximal anchor unit, wherein said resilient unit is a
loop connecting said distal and proximal anchor units, such that,
when implanted, said resilient unit has a relaxed position in one
MV plane position spring loaded against the other MV plane position
respectively, such that the cardiac muscle force of the LV brings
said loop to said spring loaded position, and said resilient unit
assists said cardiac muscle force of the LV in the other direction
towards said relaxed position.
21. The device of claim 20, wherein, when implanted, said resilient
unit has a relaxed position in said upper MV plane position spring
loaded against said MV plane down position, such that the cardiac
muscle force of the LV brings said loop to said down position, and
said resilient unit assists during diastole by assisting the LV
diastolic filling by forcing the open MV up against the blood
stream further in the direction of the LA; or wherein said
resilient unit has a relaxed position in said lower MV plane
position spring loaded against said MV plane up position, such that
the cardiac relaxation force of the LV brings said loop to the up
position, and said resilient unit assists during the systole by
assisting the LV systolic contraction by forcing the closed MV down
towards the LV apex.
22. The device of claim 20, wherein said resilient unit is locked
by an integrated bioresorbable material in such a manner that said
spring loaded action is first initiated when the resorbable
material has at least partly been resorbed, such that said device
has a delayed activation upon implantation.
23. The device of claim 1, wherein said device is bistable and is
characterized by equilibrium states defined by a diastolic up
position and a systolic down position of the MV plane.
24. The device of claim 1, wherein said device comprises a control
unit which controls said force generating unit to provide a set
sequence of said assisted movements.
25. The device of claim 24, wherein said control unit is configured
to set at least one of a frequency, a speed, and a pause time
duration of said movement.
26. A kit for improving left ventricular pump function of a heart
comprising an implantable heart assist device according to claim 1,
and a delivery system suitable for inserting said assist device
into a patient including a guide wire, a guiding catheter, and an
introducing catheter.
27. A method of delivering a medical device to improve
intra-cardiac blood circulation of a heart of a patient comprising
providing a medical system including said medical device of claim 1
and an energy source, and minimally invasively delivering said
medical system into said patient.
28. The method of claim 27, further comprising providing a delivery
system for minimally invasively delivering said medical device in
said patient, and minimally invasively delivering said force
generating unit in said patient by means of said delivery system,
delivering said energy source, and connecting said energy source to
said force generating unit.
29. The method of claim 27, wherein said delivery system includes
an introducer catheter with a valve, a guiding catheter and a guide
wire, and wherein said method comprises introducing said introducer
catheter at a puncture site into the vascular system of said
patient, inserting said guide wire into said vascular system via
said introducer catheter, navigating through the vasculature and
the heart to a desired site, inserting said guiding catheter over
said guide wire, withdrawing said guide wire, through said guide
catheter delivering said first anchor unit at a distance from a
mitral valve and delivering a second anchor unit at said mitral
valve in one of a coronary sinus and a great cardiac vein.
30. A method for improving intra-cardiac blood circulation of a
heart of a patient, said method comprising generating a force
correlating to a cardiac cycle of said heart; applying said force
to an implant arranged in a cardiac vessel in proximity to a mitral
valve of said heart so as to move said mitral valve in a mitral
valve plane in a direction to and/or from an apex of said
heart.
31. The method of claim 30, wherein said mitral valve is moved in
said mitral valve plane substantially along a long axis of a left
ventricle of said heart.
32. The method of claim 29, wherein said mitral valve is moved in a
reciprocating movement during systole towards an apex of said heart
and during diastole away from said apex.
33. The method of claim 30, further comprising wherein said
generating a force includes detecting the natural action of the
heart and providing energy for displacement of said mitral valve in
synchrony with the natural heart cycle.
34. The method of claim 30, further comprising inserting a first
anchor unit of an implantable heart assist device into said heart
and arranging a force generating unit in a position remote of said
anchor unit such that reciprocal movement of the mitral valve is
provided along an axis extending from the left atrium towards said
left ventricular apex of said heart.
35. The method of claim 30, wherein said implant is dimensioned to
be placed in the coronary sinus of the heart adjacent the mitral
valve annulus, and includes an expandable distal anchoring unit, an
expandable proximal anchoring unit, a connection unit extending
from said proximal anchoring unit to said distal anchoring unit,
and an actuating unit arranged to controllably change a length of
said connection unit after implantation, said method further
comprising: inserting said device at least partly into the coronary
sinus; expanding and anchoring said expandable distal anchor in the
coronary sinus; expanding and anchoring said expandable proximal
anchor in or outside of the coronary sinus; and after expanding and
anchoring the expandable proximal and distal anchors actuating said
actuating unit causing the connection unit to change in said length
to provide a controlled movement of the mitral valve along a short
axis of said left ventricle, transversal to said long axis, for
assisting a natural inwards and outwards movement of a lateral left
ventricular wall relative to an inter-ventricular septum.
36. The method of claim 35, wherein said change of length is made
during a single cardiac cycle.
37. A computer-readable medium having embodied thereon a computer
program for processing by a computer, said computer program
comprising code segments for controlling a medical device for
improving intra-cardiac blood circulation of a heart of a patient
by assisting left ventricular pump action, wherein a code segment
is provided for controlling a force generating unit to generate a
force in dependence of a cardiac cycle of said heart for applying
said force to an implant in a cardiac vessel proximity to and in
tissue connection with a mitral valve of said heart for an assisted
movement of said cardiac vessel and thus said mitral valve in a
mitral valve plane in a direction to and/or from an apex of said
heart.
Description
RELATED APPLICATIONS
[0001] This application claims priority to International Patent
Application No. PCT/SE2011/050337, International Filing Date Mar.
25, 2011, entitled A Device, A Kit And A Method For Heart Support,
which claims priority to U.S. Provisional Application Ser. No.
61/317,619 filed Mar. 25, 2010, and Swedish application Serial No.
SE1050282-1 filed Mar. 25, 2010, both entitled Device, A Kit And A
Method For Heart Support, all of which are hereby incorporated
herein by reference.
FIELD OF THE INVENTION
[0002] The present invention relates to an intra-vascular blood
circulation enhancing apparatus, a system for intra-vascular blood
circulation enhancement and a method for enhancing left ventricular
pump function of a patient. The present invention may specifically
be used to enhance the pump function of the left ventricle as a
permanent measure for treating a heart failure disease where the
heart function is deficient.
BACKGROUND OF THE INVENTION
[0003] Where the heart function is chronically insufficient, there
may be a need to permanently aid the heart function. Heart failure
(HF), more often called Congestive Heart Failure (CHF), is in
general a condition where the heart, is unable to support the body
tissue with its metabolic demands and to sustain adequate blood
pressure and cardiac output. The term Congestive relates to a
congestion of blood and fluids in front of the pumping ventricles
as a result of insufficient forward pumping, most often caused by
disease of the left ventricle muscle. A peculiarity of heart cells
is that they do not regenerate after damage or cell death, thus
conditions have a tendency to worsen rather than heal after heart
cell damage. There are many reasons for heart cell death, the most
common cause is ischemic heart disease, a condition where the
arteries feeding the heart muscle get clogged, causing myocardial
infarctions (MI). Viruses may damage the muscle cells, and some
diseases, for instance cardiomyopathy have unknown reasons. End
stage of long standing high blood pressure may also cause end stage
heart failure. Heart strengthening drugs like digoxin or treatment
with diuretics help for a while, but are all only treating
symptoms. CHF is a progressive untreatable, disabling and finally a
deadly condition. According to the American Heart Association
homepage, there are in the US at present more than 5 Million
patients living with CHF and 550 000 are added every year. 40 000
in the US are in such a bad state that only a heart transplant will
keep them alive. However, due to the limited number of suitable
organs only 2500 transplants are done yearly in the US. One may
extrapolate the numbers for the rest of the industrialized
world.
[0004] Total artificial heart, where the whole native heart is
excised and replaced with a mechanical device was introduced in the
1960's by DeBakey, in the 1980's by among others Jarvik and
recently by Copeland (CardioWest, Total Artificial Heart). However,
these devices are still based on complex designs and are very
invasive to install in the patient. Failure in operation of the
device is fatal.
[0005] There are other techniques supporting only the failing left
ventricle, known as left ventricle assist devices (LVAD). The most
popular LVADs are the Novacor and the HeartMate devices. Common for
this devices is the demand for major open heart surgery utilizing
extracorporeal circulation by means of a Heart- and Lung-machine
while stopping (or excising) the heart. These are bulky devices, a
Novacor weights 1.800 grams, a HeartMate 1.200 grams. There are
smaller axial flow pumps available nowadays, the HeartMate II, the
Jarvik 2000 and the MicroMed DeBakey VAD. In addition, major open
heart surgery is still necessary to install and connect these
devices to the left ventricle cavity and the aorta by means of
large vascular grafts. The mentioned devices have almost
exclusively been used as a bridge to a heart transplant due to high
frequency of complications, high mortality and limited durability.
Their use has also been limited because of high prices of up to 150
000 $ only for the device.
[0006] None of the devices for permanent implant described are
feasible for minimal invasive catheter based insertion, on the
contrary, they all involve major open heart surgery. There is
obviously a demand for simpler devices, it is the scope of the here
presented invention to omit major cardiac surgery and to allow
implant with catheter technique.
[0007] Moreover, health care is permanently searching for improved
devices and methods.
[0008] Hence, there is a need of an improved system and/or method
for permanently enhancing or assisting left ventricular pump
function of a heart of a patient. The system is advantageously not
interfering with the cardiac cycle of the heart.
[0009] Hence, an improved system and/or method for permanently
enhancing or assisting left ventricular pump function of a heart of
a patient would be advantageous and in particular allowing for
increased flexibility, cost-effectiveness, long-term function,
and/or patient friendliness would be advantageous.
SUMMARY OF THE INVENTION
[0010] Accordingly, embodiments of the present invention preferably
seek to mitigate, alleviate or eliminate one or more deficiencies,
disadvantages or issues in the art, such as the above-identified,
singly or in any combination by providing a medical device, a kit,
a method, and a computer-readable medium, according to the appended
patent claims.
[0011] Embodiments of the invention take advantage of an improved
understanding of left ventricular pump action and the close
relationship between the Coronary Sinus (CS), the Great Cardiac
Vein (GCV) and the Mitral valve (MV). Embodiments of the invention
are providing movement of the CS and the GCV and thereby the MV
along the long axis of the left ventricle (LV) towards and/or away
from the heart apex, in synchrony with the cardiac cycle. In some
embodiments energy is provided for this assisting movement. The
here described embodiments of permanent implants do not take over
or replace the remaining left ventricular pump function, they
rather augment, improve, enhance or support the remaining natural
pump function by means of an at least partly increased up and/or
down movement of the mitral valve that works as a blood
displacement or propulsion piston, when it is closed during the
systole.
[0012] The here presented innovation is based on recent
understanding of how the left ventricle functions and also on
utilizing an undiscovered favourable anatomy of the left heart.
Modern catheter based technology is integrated in embodiments of
the here described device, system and methods.
[0013] Modern imaging of the beating heart has contributed largely
to the understanding of left ventricle pump action. The pumping
force of the left ventricle has before been understood to be a
result of the heart muscle contracting and squeezing (systole)
around the amount of blood enclosed inside the left ventricle after
closure of the mitral valve, increasing the pressure and thereby
forcing the blood towards the aortic valve, forcing this to open
and ejecting the blood into the ascending aorta. When the squeezing
is completed, an intermission occurs (diastole), during which a new
portion of blood enters the left ventricle cavity from the left
atrium.
[0014] Ultrasound imaging and Magnetic Resonance Imaging (MRI) has
revealed that this previously taught mode of function is not
completely true. Instead, one may describe two types of pump
action, a long axis and a short axis action. MRI can show that
there is a movement of the atrioventricular mitral valve (MV) plane
downwards along the left ventricle long axis that extends from the
atrium towards the ventricle's lower end, the apex. The left
ventricle muscle cells are pulling the whole mitral valve plane,
including the mitral valve annulus and part of the left atrial wall
(that is stretching) towards the heart apex. By pulling the closed
mitral valve towards the heart apex, the mitral valve becomes a
piston in a blood displacement pump.
[0015] The downwards movement of the mitral valve is in a healthy
human up to approximately 2 centimetres. The downwards movement
accelerates the blood column away from the left atrium and towards
the aortic valve in a continuous movement. By means of MRI
technology one is able to virtually mark separate pixels inside the
blood column and follow their movement. It is possible to show that
the blood column flows more or less continuously from the left
atrium to the ascending aorta without ever stopping. The blood
column is accelerated by the mitral valve piston moving up and down
along the cardiac long axis, opening every time it takes a new
scoop of blood in an upward movement to the atrium, and closing
just before moving back toward the apex.
[0016] The inventor of the present application realized that the
location of the Coronary Sinus (CS) and the Great Cardiac Vein
(GCV), very close to the mitral valve, can be utilized for
enhancement of the left ventricular pump function. For instance a
downwards movement of the mitral valve substantially along the long
axis of the left ventricle may be supported. By actively moving, or
supporting a still existing natural cardiac movement of, the CS and
the GCV downwards towards the apex one simultaneously can move the
mitral valve in the same direction.
[0017] The Coronary Sinus and the Great Cardiac Vein represent the
large veins of the heart. The arterial blood of the heart passes
the capillaries (the smallest vessels of the heart) and then enters
the venous plexus in the heart tissue wall. Then the venous blood
flows together into veins located on the heart surface. Distally
the cardiac veins are small but unite together into larger and
larger veins before flowing into the GCV and the CS. All the venous
blood from the heart pours into the CS and then flows through the
coronary sinus ostium (orifice) into the Right Atrium (RA) on the
right side of the heart.
[0018] The major part of the CS and part of the GCV is located on
the left atrial side of the mitral valve annulus. This is the part
of the LA wall that stretches in a healthy heart when the MV is
moving down towards the apex. The GCV then crosses the MV plane and
annulus towards the LV side and join the anterior inter-ventricular
vein on the front side of the heart. Thus the CS and the GCV
encircle at least 2/3 of the MV circumference, substantially in the
same plane as the mitral valve plane, and are attached or embedded
in tissue adjacent to the mitral valve.
[0019] Since the ostium of the coronary sinus is on the right side
of the heart in the RA, one has easy access to the CS, the GCV and
their side branches of veins on the heart surface by puncturing a
peripheral vein, e.g. in the groin on the neck or in an arm. By
means of modern catheter based technique, embodiments of the here
disclosed device may be placed in position adjacent the mitral
valve without major cardiac surgery. As matter of fact it is
possible to place the device while the patient is conscious using
only local anaesthesia, a common practice for implanting pacemakers
and Intra Cardiac Defibrillators (ICD).
[0020] According to one aspect of the invention, a medical device
is provided for enhancing intra-cardiac blood circulation of a
heart of a patient by permanently assisting left ventricular pump
action. The device has at least one first anchor unit implanted in
a cardiac vessel of said heart, e.g. a side branch of the coronary
sinus (CS) or the great cardiac vein (GCV). The first anchor unit
may be an expandable stent structure for anchoring the anchor unit
in the cardiac vessel, and/or wherein the first anchor unit has at
least one tissue anchoring element, such as a hook or barb.
[0021] In embodiments the device has at least one second anchor
unit implanted in the cardiac vessel, wherein the second anchor
unit is located in the CS or the GCV. The second anchor may serve
in transferring force from a remote force generating unit.
[0022] Thus, the device has a force generating unit that is in
communication with said first and second anchor units, wherein said
force generating unit generates a force in dependence of a cardiac
cycle of said heart. The anchor units receive said force in such a
manner that an assisted movement of said cardiac vessel and thus
said mitral valve in a mitral valve plane is provided in a
direction to and from an apex of the heart. However, in a specific
embodiment, the second anchor unit may also have an integrated
electrical motor instead and the force generating unit is the
motor, the device having a connecting unit between the motor and
the first anchor for the communication, and wherein the force is
provided by the motor. In turn, the integrated electrical motor is
provided with electrical energy from a remote energy source by
means of an electrical cable.
[0023] By means of the applied force, the mitral valve is during
systole assisted to move the mitral valve plane along the long axis
of the left ventricle (LV) towards an apex of the heart and/or
during diastole assisted to move the mitral valve plane away from
the apex by the force for assisting the pump action of the heart.
The assisted movement is provided in a controlled manner to support
a natural movement of the mitral valve. When the mitral valve
movement towards the apex is at least partly assisted during
systole, the (still existing) natural pumping force of the heart is
augmented while ejecting blood into the aorta. When the mitral
valve movement away from the apex is at least partly assisted
during diastole, the natural filling of the left ventricle of the
heart is supported. Thus the (still existing) natural pumping
function of the heart is augmented by an improved filling degree.
The force generating unit is operatively connected to a remote
energy source to receive energy therefrom and to controllably
provide the assisting movement in synchrony with the natural heart
cycle.
[0024] In some embodiments the force generating unit is an
actuating unit for providing the force as a mechanical force, and
wherein the first anchor unit and the actuating unit are in
communication via a connecting unit for transferring the force and
providing the movement.
[0025] In some embodiments the force is a magnetic unit for
providing the force as a magnetically induced force. In such
embodiments, the two anchors are magnetic, and wherein the first
magnetic anchor unit and the second magnetic unit in the CS or GCV
are in magnetic communication for transferring the force and
providing the movement. At least one magnetic anchor unit is an
electromagnet. At least one of the electromagnets is arranged to
change polarity in synchrony with the cardiac cycle. While the
second electromagnet anchor always is located in the CS or GCV, the
first magnet may be positioned in various locations. In some
embodiments the first magnet is located inside a side branch of the
vein system on the left ventricular wall, e.g. the IAV, it may also
be located in the left ventricle attached to the LV wall, or in the
right ventricle, the right atrium or the left atrium of the heart,
or on the left ventricular outer wall of the heart. In other
embodiments the first magnetic anchor may not be located in, but
adjacent to the heart, such as on the pericardium, the diaphragm,
the spine or thoracic cage, in the pleura or under the skin.
[0026] In some embodiments the device has a remote energy source, a
control unit, and a sensor for measuring physiological parameters
related to the cardiac cycle activity providing a sensor signal.
The sensor signal is provided to the control unit which controls
the force generating unit to provide the movement by energy from
the remote energy source and based on the sensor signal. The remote
energy source may have a mechanical section where rotational or
linear motion is generated. The device further may have an
extension unit extending from the mechanical section, wherein the
mechanical section is the force generating unit and wherein the
motion is transferred in operation of the mechanical section to the
first and second anchor unit for the movement of the mitral valve
plane via an extension unit. The remote energy source is controlled
by the control unit to provide electrical energy a) to one or more
electromagnetical anchor units affixed in relation to the mitral
valve, or b) to at least one force generating unit arranged at or
in the heart, to provide the movement of the mitral valve
plane.
[0027] In another embodiment, the first anchor unit may be
implanted in the GCV or its continuation, more specifically in the
anterior interventricular vein (AIV), and the second anchor unit
may be implanted in the CS. An elongate extension unit connects the
first and second anchor units in a loop shape such that they are in
mechanical communication. Thus, the part of the device that is
located in the CS and the GCV geometrically forms a loop around 2/3
of the MV, and very close to it. The extension unit extends
proximally beyond the second anchor unit to a mechanical actuator
unit arranged to rotate the extension unit synchronized with the
cardiac cycle, wherein the device has different operative positions
upon rotation of the extension unit, including upon rotation of the
extension unit in a first direction a diastole operative position
where the loop shaped extension unit is flexed towards the left
atrium and the CS, GCV and MV are moved towards the left atrium,
and a second operative position where upon rotation of the
extension unit in a second direction, opposite the first direction,
where the loop shaped extension unit is flexed towards the LV apex
and the CS, GCV and MV are moved towards the LV apex.
[0028] In some embodiments the device is a non-powered device. The
force generating unit may be a resilient unit, and the first anchor
unit may include a distal anchor unit. The distal anchor and a
proximal anchor unit may be arranged in the AIV, CS and GCV. The
resilient unit may be a loop connecting the distal and proximal
anchor units, wherein the resilient unit has a relaxed position in
an upper MV plane position spring loaded against a MV plane down
position, such that the cardiac muscle force of the LV brings the
loop to the down position, and the resilient unit assists during
the diastole by assisting the LV diastolic filling by forcing the
open MV up against the blood stream further in the direction of the
LA. In other embodiments, the resilient unit may have a relaxed
position in a lower MV plane position spring loaded against a MV
plane up position, such that the cardiac relaxation force of the LV
brings the loop to the up position, and the resilient unit assists
during the systole by assisting the LV systolic contraction by
forcing the closed MV down towards the LV apex.
[0029] The resilient unit may be initially locked by an integrated
bioresorbable material, such as PLLA, Polyvinyl or Polylactid, in
such a manner that the spring loaded action is first initiated when
the resorbable material has at least partly been resorbed, such
that the device has a delayed activation upon implantation.
[0030] According to another aspect of the invention, a kit is
provided, for permanently enhancing or augmenting the left
ventricular pump function of a heart. The kit includes an
implantable heart assist device according to the first aspect of
the invention, and a delivery system suitable for inserting the
assist device into a patient including a guide wire, a guiding
catheter, and an introducing catheter.
[0031] According to another aspect of the invention, there is
provided a kit for permanently enhancing the left ventricular
function of a heart. The kit comprises a left ventricular
enhancement or augmentation system placed in the coronary sinus and
in adjacent tissue able to move the mitral valve plane, its annulus
and leaflets along the direction of the long axis of a left
ventricle in synchrony with the electrocardiogram, an energy source
and a delivery system for carrying the augmentation system to
desired positions in the heart.
[0032] The kit may provide a package to a surgeon who is about to
introduce an enhancement system into a patient. Thus the kit
provides both implants that may be used for permanently treating
the patient and a delivery system which may be used for inserting
the implants. The enhancing unit may be mounted in the delivery
system for storage, while the energy source may be packaged
separately for connection during surgery. The kit may further
comprise a guide wire for guiding insertion of the delivery system
to the desired positions through the vascular system of a patient.
The delivery system may also comprise a guiding catheter which is
arranged to be pushed over the guide wire to the desired position.
Also an introducing catheter for establishing access to the
vascular system through energy source pocket is part of the kit. A
valve that is prohibiting blood backflow but still allows a guide
wire or a guiding catheter to pass through is included in the
introducing catheter.
[0033] According to yet another aspect of the invention, a method
is provided for permanently enhancing intra-cardiac blood
circulation of a heart of a patient by assisting left ventricular
pump action. The method includes generating a force in dependence
of a cardiac cycle of the heart by means of a force generating
unit, applying the force to an implant in a cardiac vessel
proximity to and in tissue connection with a mitral valve of the
heart for an assisted movement of the cardiac vessel and thus the
mitral valve in a mitral valve plane in a direction to and/or from
an apex of the heart.
[0034] The assisted movement may include a controlled movement of
the mitral valve in a mitral valve plane substantially along a long
axis of a left ventricle of the heart by the force.
[0035] The aforementioned controlled movement may in some
embodiments include moving the mitral valve in the heart in a
reciprocating movement during systole towards an apex of the heart
and during diastole away from the apex for assisting the pump
action of the heart.
[0036] The generating a force in dependence of a cardiac cycle of
the heart may include detecting the natural action of the heart,
such as by measuring an electrocardiogram, a blood pressure wave, a
blood flow, or acoustic signals of the heart, and providing energy
for displacement of the mitral valve in synchrony with the natural
heart cycle. Thereby is the natural up and down movement of a
mitral valve assisted during a heart cycle.
[0037] In another embodiment the assisted movement may include a
controlled movement of the mitral valve in a mitral valve plane
substantially along a long axis of a left ventricle of the heart by
the force and in addition also in a short axis of a left
ventricle.
[0038] This additional transversal controlled movement may in some
embodiments include moving the lateral LV wall in the heart in a
reciprocating movement during systole towards an inter-ventricular
septum of the heart and during diastole away from an
inter-ventricular septum for assisting the pump action of the heart
along the short axis of a LV of a heart.
[0039] The generating of a force in dependence of a cardiac cycle
of the heart may include detecting the natural action of the heart,
such as by measuring an electrocardiogram, a blood pressure wave, a
blood flow, or acoustic signals of the heart, and providing energy
for displacement of the mitral valve in synchrony with the natural
heart cycle. Thereby is the natural up and down movement of a
mitral valve assisted during a heart cycle as well as the natural
inwards and outwards movement of the lateral LV wall relative to an
intra-ventricular septum, along the short axis of a LV.
[0040] According to a further aspect of the invention there is
provided a method for permanently treating failure of a left
ventricle in a patient. The method comprises inserting a left
ventricular enhancement system into the coronary sinus and adjacent
veins and tissue and arranging the enhancement unit in desired
positions such that the enhancement unit may be connected to energy
source means.
[0041] The method comprises transfer of external energy to the
enhancement unit in the coronary sinus and the great cardiac vein
in order to move the mitral valve up and down along an axis from
the left atrium towards the left ventricular apex in synchrony with
the natural heart cycle.
[0042] The method includes also insertion of an energy source under
the skin. The method allows connection of electrical cables or
device extensions for transferring power to the energy source in
such a way that the energy source may be located under the skin but
outside a vein.
[0043] Further the method involves transfer of electrical energy
through the skin either by cable or electro-magnetic in order to
store electrical energy in a battery under the skin.
[0044] In addition hereto the method comprises the use of computer
chips and algorithms in order to detect the spontaneous cardiac
cycle and guide the enhancing device in accordance to the heart
cycle by means detecting an electrocardiogram.
[0045] A preferable method of placing an energy source would be to
do this surgically through a small incision in the skin and make a
small pocket in the subcutaneous tissue under the skin. Part of the
method would be to use the same pocket to gain access to a vein by
means of puncturing the introducer catheter into the vein through
the pocket. Still another part of the method would be to get access
to inside of the left heart by means of puncturing an artery in
order to place anchors. Further it is part of the method to attach
an anchor to the atrial septum in a natural persistent foramen
ovale or to attach it to the atrial wall by means of hooks. Finally
anchors may be attached to the inside of the ventricles or atria by
means of hooks.
[0046] The method may comprise in some embodiments include
inserting a first anchor unit of an implantable heart assist device
according to the first aspect of the invention into the coronary
sinus and/or adjacent veins and tissue, and arranging the force
generating unit in a position remote of the anchor unit such that
the reciprocal movement of the mitral valve is provided along an
axis extending from the left atrium towards the left ventricular
apex of the heart.
[0047] According to yet a further aspect of the invention a medical
procedure is provided that includes delivering a medical device
adapted to enhance intra-cardiac blood circulation of a heart of a
patient by assisting left ventricular pump action. The procedure
may comprise providing a medical system including the medical
device of some embodiments of the first aspect of the invention
that are supplied with external energy, and providing an energy
source, as well as minimally invasively delivering the medical
system in the patient.
[0048] The procedure may include providing a delivery system, such
as the aforementioned kit for minimally invasively delivering the
medical device in the patient, and minimally invasively delivering
the force generating unit of the medical system in the patient by
means of the delivery system, delivering the energy source, and
connecting the energy source and the force generating unit.
[0049] The procedure may comprise using a delivery system that
includes an introducer catheter with a valve, a guiding catheter
and a guide wire, and introducing the introducer catheter at a
puncture site into the vascular system of the patient, inserting
the guide wire into the vascular system via the introducer
catheter, navigating through the vasculature and the heart to a
desired site, inserting the guiding catheter over the guide wire,
withdrawing the guide wire, through the guide catheter delivering a
first anchor unit at a distance from the mitral valve and
delivering a second anchor unit at a mitral valve.
[0050] According to a further aspect of the invention, a
computer-readable medium having embodied thereon a computer program
for processing by a computer is provided. The computer program
includes code segments for controlling a medical device for
permanently enhancing intra-cardiac blood circulation of a heart of
a patient by assisting left ventricular pump action. A code segment
is provided for controlling a force generating unit to generate a
force in dependence of a cardiac cycle of said heart for applying
said force to an implant in a cardiac vessel proximity to and in
tissue connection with a mitral valve of said heart for an assisted
movement of said cardiac vessel and thus said mitral valve in a
mitral valve plane in a direction to and/or from an apex of said
heart.
[0051] Further embodiments of the invention are defined in the
dependent claims, wherein features for the second and subsequent
aspects of the invention are as for the first aspect mutatis
mutandis.
[0052] It should be emphasized that the term "comprises/comprising"
when used in this specification is taken to specify the presence of
stated features, integers, steps or components but does not
preclude the presence or addition of one or more other features,
integers, steps, components or groups thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0053] These and other aspects, features and advantages of which
embodiments of the invention are capable of will be apparent and
elucidated from the following description of embodiments of the
present invention, reference being made to the following
accompanying drawings.
[0054] FIGS. 1a and 1b are schematic illustrations of the human
heart depicting the cardiac anatomical structures that are
involved.
[0055] FIGS. 2a and 2b are schematic illustrations of the anatomy
of the cardiac vein system including the coronary sinus, the great
cardiac vein and the side branches as well as the level of the
mitral valve plane in relation to the left ventricular axis.
[0056] FIGS. 3 and 4 are schematic illustrations that explain the
normal movement of the vein system of the heart and the mitral
valve during a normal cardiac cycle.
[0057] FIGS. 5-9 are schematic illustrations depict schematic how
the here presented invention may augment the mitral valve movement
utilizing different embodiments.
[0058] FIGS. 10-12 are schematic illustrations that describe
different embodiments utilizing pulling and pushing forces in order
to augment the mitral valve movement.
[0059] FIGS. 13-16 are schematic illustrations that describe
different embodiments utilizing rotation forces in order to augment
the mitral valve movement.
[0060] FIG. 17 is a schematic illustration that shows a remote
energy source.
[0061] FIGS. 18-20 are schematic illustrations that show a delivery
system.
[0062] FIGS. 21-24 are schematic illustrations that explain a
method of delivering an augmentation system.
[0063] FIG. 25 is a flowchart of the method.
DESCRIPTION OF EMBODIMENTS
[0064] Specific embodiments of the invention will now be described
with reference to the accompanying drawings. This invention may,
however, be embodied in many different forms and should not be
construed as limited to the embodiments set forth herein; rather,
these embodiments are provided so that this disclosure will be
thorough and complete, and will fully convey the scope of the
invention to those skilled in the art. The terminology used in the
detailed description of the embodiments illustrated in the
accompanying drawings is not intended to be limiting of the
invention. In the drawings, like numbers refer to like
elements.
[0065] Embodiments of the invention take advantage of new
discoveries of left ventricular pump action and the close
relationship between the Coronary Sinus (CS), the Great Cardiac
Vein (GCV) and the Mitral valve (MV). Embodiments are by means of
external power able to provide a movement of the CS and the GCV and
thereby the MV along the long axis of the left ventricle (LV)
towards the heart apex, in synchrony with the cardiac cycle. The
here described permanent implant does not take over or replace the
remaining left ventricular pump function, it will rather augment
the pump function by means of an increased up and/or down movement
of the mitral valve plane in relation to the long axis of the left
ventricle.
[0066] Now turning to the Figures, FIGS. 1a, 1b, 2a and 2b depict
the structures of the heart 1 of which at least some are involved
in embodiments of the invention. 2 is the Superior Vena Cava (SVC),
4 is the right atrium (RA), 6 is the CS ostium, 8 is the CS first
part, the remaining part of the CS is behind the heart, e.g.
depicted in FIG. 1b. 10 is the Inferior Vena Cava (IVC), 12 is the
Great Cardiac Vein (GCV) at the level of the MV annulus 18. 14 is
the Left Atrium cavity (LA), 16 is the LA wall, 18 is the mitral
valve annulus, 19 the whole mitral valve, 20 is the anterior
leaflet and 21 is the posterior leaflet of the mitral valve. 22 is
the LV muscular wall, 24 are the papillary muscles, 26 is the apex
of the left ventricle. 28 is the aortic valve, 30 the aorta
ascendens, 32 the inter-ventricular muscular septum, 34 the left
ventricular cavity and 36 the right ventricular cavity. 38 is the
right ventricular muscular wall and 40 is the tricuspid valve.
[0067] FIGS. 1b and 2a show a schematic view of a heart, depicting
the vein system, wherein reference numeral 42 is the anterior
inter-ventricular vein, and 44 are lateral wall veins, side
branches in the outside wall of the LV, 46 is the posterior
descending vein. These side branch veins are also often referred to
as the left marginal vein, the posterior veins of the left
ventricle or the middle cardiac vein. However, they are all side
branches of the CS or the GCV whatever they are called in the
literature.
[0068] In FIG. 2b. the mitral valve plane 48 is shown in relation
to the vein system and the LV long axis 49, which is close to
perpendicular to the MV valve plane 48.
[0069] FIG. 3 is a schematic view of the movements in systole of
the mitral valve plane 48 in relation to the LV apex 26, the GCV 12
(and CS) the MV anterior 20 and posterior 21 leaflets, the MV
annulus 18, the aortic valve 28, the LA wall 16 and the LA cavity
14 during a normal heart beat. The large arrow x shows the
direction of the blood flow and the small arrow y illustrates the
direction of movement of the MV plane 48, the GCV and the CS until
the end systole position is reached ("down" position). In the
cardiac cycle, the following moments are shown in FIG. 3: a) is
just before systole, b) during systole and c) end of systole.
[0070] With reference to FIG. 4, a schematic view of the movements
in diastole is shown of the mitral valve plane 48 in relation to
the LV apex 26, the GCV 12 (and CS), the MV anterior 20, and
posterior 21 leaflets, the MV annulus 18, the aortic valve 28, the
LA wall 16 and the LA cavity 14 during a normal heart beat. The
large arrow x shows the direction of the blood flow and the small
arrow y the direction of movement of MV plane 48, the GCV and the
CS, until the end diastole position is reached ("up" position). In
the cardiac cycle, the following moments are shown in FIG. 4: a)
early diastole, b) late diastole and c) end of diastole, at the end
of diastole the mitral valve is now closed and ready for the next
move downwards in the following systole.
[0071] FIG. 5 is a schematic view of an embodiment of a medical
device for cardiac assist when inserted in the heart 1. Some
embodiments, as the present device, has two anchor units. A first
anchor unit 50, is located in the CS 8 and/or the GCV 12. The
second anchor unit 52 is located remote from the first anchor unit.
The second anchor unit 52 is for instance arranged inside a side
branch of the vein system on the LV wall 22. The two anchors 50, 52
are in communication with each other. They are for instance, as
illustrated, connected by means of a pulling and pushing unit 54
that can move the two anchors relative to each other. The figure
depicts, as in FIG. 3, the movements in systole of the mitral valve
plane 48 in relation to the LV apex 26, the GCV 12 (and CS) the MV
anterior 20 and posterior 21 leaflets, the MV annulus 18, the
aortic valve 28, the LA wall 16 and the LA cavity 14 during an
augmented or assisted heart beat. The pulling and pushing unit 54
forces, powered by a power unit (not shown), such as a remote or
external power unit, the two anchors closer to each other, and is
thereby augmenting the force and extent of the downwards movement
of the mitral valve 19. The left ventricular pump action is
assisted. The large arrow (x) show the direction of the blood flow
and the small arrow (y) the direction of MV plane, the GCV and the
CS. In the cardiac cycle, the following moments are shown in FIG.
5: a) is just before systole, b) during systole and c) end of
systole.
[0072] FIG. 6 is a schematic view of one embodiment of the
invention when inserted in the heart 1. The two anchors, 50 is
located in the CS 8 or the GCV 12, the other, 52 is located inside
a side branch of the vein system on the LV wall 22. The two anchors
are connected by means pulling and pushing unit 54 that can move
the two anchors relative to each other. The figure depict as in
FIG. 4 the movements in diastole of the mitral valve plane 48 in
relation to the LV apex 26, the GCV 12 (and CS) the MV anterior 20
and posterior 21 leaflets, the MV annulus 18, the aortic valve 28,
the LA wall 16 and the LA cavity 14 during an augmented heart beat,
the pulling and pushing unit 54 forces, powered by means of an
remote or external power unit 84 (not shown) the two anchor units
away from each other. As the anchors are fixed to the tissue where
they are anchored, the tissue structure is moved with the anchor
unit(s). The anchor unit(s) are thereby augmenting the force and
extent of the upwards movement of the mitral valve 19 towards the
LA. Thereby the device is enhancing the diastolic filling of the LV
before the next heart beat. Hence, even during diastole the cardiac
assist is provided. The large arrow x shows the direction of the
blood flow and the small arrow y the direction of MV plane 48, the
GCV and the CS. In the cardiac cycle, the following moments are
shown in FIG. 6: a) early diastole, b) late diastole and c) end of
diastole, the mitral valve is now closed and ready for the next
move downwards.
[0073] A prototype of the invention was built, using a linear
accelerator and a computer. The computer allowed action in
synchrony with an electrocardiogram. The prototype was tested in an
animal experiment. The chest of a 60 kilogram pig was opened
between the ribs. A rod from the linear accelerator was attached to
the mitral valve annulus from the outside of the heart. The heart
function was depressed by means of drugs. After activating the
device an increase in arterial blood pressure and cardiac output
was observed.
[0074] FIG. 7 is a schematic view of another embodiment of the
invention when inserted in the heart 1. The device has two anchor
units. A first anchor unit 56, is located in the CS 8 and/or the
GCV 12. The second, remote, anchor unit 58, is located inside a
side branch of the vein system on the LV wall 22 or is attached to
the LV outer wall. Here, the two anchors are magnets. Preferably
they are provided in form of electromagnets, but one or the other
magnetic anchoring unit may also be a traditional permanent magnet.
The electromagnetic magnets are arranged to change polarity,
synchronized with the heart cycle in order to change between
pulling towards each other and pushing away from each other. There
are no physical connecting units between the magnetic anchoring
units. The anchoring units are only in magnetic connection. When
the anchoring units have different polarity they move the two
anchors closer to each other and correspondingly when the polarity
is equal they move the two anchors away from each other. FIG. 7
depicts, as in FIG. 3, the movements in systole of the mitral valve
plane 48 in relation to the LV apex 26, the GCV 12 (and CS) the MV
anterior 20 and posterior 21 leaflets, the MV annulus 18, the
aortic valve 28, the LA wall 16 and the LA cavity 14 during an
augmented heart beat. The magnetic anchors 56 and 58 attract each
other and forces by means of magnetic power the two anchors closer
to each other, and is thereby augmenting the force and extent of
the downwards movement of the mitral valve 19. The large arrow
shows the direction of the blood flow and the small arrow the
direction of MV plane, the GCV and the CS and the magnet 56. In the
cardiac cycle, the following moments are shown in FIG. 7: a) is
just before systole, b) during systole and c) end of systole.
[0075] FIG. 8 is a schematic view of the same embodiment as in FIG.
7 in diastole. The first anchor unit 56 is located in the CS 8
and/or the GCV 12. The second anchor unit 58 is located remote from
the first anchor unit 56. Here, the second anchor unit is located
inside a side branch of the vein system on the LV wall 22.
Alternatively, or in addition, it may be attached to the LV outer
wall. The two anchors are magnets, preferably electromagnets, but
one or the other may also be a traditional permanent magnet. The
electromagnetic magnets may change polarity synchronized with the
heart cycle in order to change between pulling towards each other
and pushing away from each other. There are no physical connecting
units. When the anchoring units have different polarity they move
the two anchors closer to each other and correspondingly when the
polarity is equal they move the two anchors away from each other.
FIG. 8 depicts, as in FIG. 4, the movements in diastole of the
mitral valve plane 48 in relation to the LV apex 26, the GCV 12
(and CS) the MV anterior 20 and posterior 21 leaflets, the MV
annulus 18, the aortic valve 28, the LA wall 16 and the LA cavity
14 during an augmented heart beat. The magnetic anchors 56 and 58
now have equal polarity (both negative or both positive) and push
each other away and thus the two anchors are forced away from each
other by means of magnetic power, and is thereby augmenting the
force and extent of the upwards movement of the mitral valve 19.
The large arrow shows the direction of the blood flow and the small
arrow the direction of MV plane and the magnet 56, the GCV and the
CS. In the cardiac cycle, the following moments are shown in FIG.
8: a) early diastole, b) late diastole and c) end of diastole.
[0076] In FIG. 9 an alternate positioning of the second magnet
anchor unit 58 is shown. The second anchor unit 58 can be
electromagnetic or classic permanent magnetic. The second anchor 60
can be electromagnetic or classic permanent magnetic. When being
permanent magnetic, the first magnetic anchor 56 is an
electromagnetic unit with selectively activateable magnetic
polarity. The second anchor 60 can be placed in different positions
in the heart. However, positions outside the heart are also
possible in certain embodiments. Location 61 indicates a position
where the second anchor 60 is not attached to or in the heart. One
such position is in the pericardium. Another position is in the
pleura or under the skin. Possible attachment sites include the
pericardium, the diaphragm. The spine or the thoracic cage (ribs
and sternum) are also suitable sites for attachment of the second
anchor 60. Positions 62, 64, 66, 68 indicate positions for the
second magnet anchor 60 relative the heart. Position 62 is located
in the left ventricle and position 64 is located in the right
ventricle. Position 66 is located in the RA, preferably in the so
called atrial septum between the RA and the LA. One good position
is in the foramen ovale of the atrial septum where often an opening
is present to the LA. In this embodiment, the second anchor unit
may have the shape of a septal occluder and provide both septal
leakage occlusion and allows for support of the cardiac function.
Position 68 indicates a position in the LA, again a good attachment
site would be the atrial septum, another good position in the LA
would be the LA appendage (LAA, not shown). In this embodiment, the
second anchor unit may have the shape of an LAA occluder and
provides both LAA occlusion and allows for support of the cardiac
function. These are only examples and a person skilled in the art
may think of multiple variations that would work equally well for
the purpose.
[0077] In FIG. 10a another embodiment is shown where the supporting
or assist force is executed by means of a mini motor 70 integrated
in the CS anchor and/or GCV anchor. MEMS
(micro-electro-magnetical-systems) technology could be utilized for
constructing such a motor. One or more second anchor units 72 are
arranged in one or more side branches 44, to which the connecting
unit 54 is attached, respectively.
[0078] Permanent magnets in embodiments may be conventional iron
magnets. Alternatively, super magnets, like Neodymium rare earth
magnets may be used to improve efficiency and/or reduce size of the
units of the cardiac assist system, when comprising magnetic
elements.
[0079] An anchor unit may for instance be provided in form of a
stent. The stent serves as an anchor in a vessel. Such a stent
could be a self expanding stent for instance made of a shape memory
material, like a shape memory metal like superelastic Nitinol. The
mini motor 70 could then be integrated in the stent structure (not
shown). The stent could also be a stent made of a material or
having a structure that has to be expanded by means of a balloon,
for instance made of stainless steel or another metal suitable for
the purpose. Alternatively, or in addition, an anchor unit is made
with hooks that dig into the tissue made of similar materials,
these are only examples and a person skilled in the art may think
of multiple variations that would work equally well for the purpose
when reading the present description. Thus, the motor 70 is
attached to the vessel structure. This may be made with stent
technology and/or by means of hooks that a person skilled in the
art will find multiple solutions for. However, common for all these
solutions is that they will be executed by means of catheter based
techniques by means of puncture of a vessel, preferably a vein,
through the skin.
[0080] Multiple sets of motors 70, anchors 72 and connecting units
54 may be implanted simultaneously and connected to one or more
energy sources 84 (not shown) as is described in FIG. 10b.
Electrical power for the mini motors is provided from the remote
energy source 84 by means of insulated cables 74.
[0081] In still another embodiment shown in FIGS. 11a and 11b, the
energy is mechanically transferred from the remote energy source 84
to the movement of the MV plane 48. The mechanical force may be
provided through an extended connecting unit 54, like a wire or
elongate flexible rod. The movement is transferred all the way from
a mechanical actuator, e.g. at the remote energy source, to the
anchor unit 72, through the CS or GCV anchor 76. The anchor unit 76
may have guiding units 80 for the connecting unit 54 in order to
transfer the mechanical movement from the anchor 76 into the used
side branch 44 of the vein system. A guiding sheath 78 may be
fixated in the anchor 76 and in the energy source 84 in such a way
that when pulling in the connecting unit 54 inside by the
mechanical actuator, e.g. at the energy source, relatively to the
guiding sheath 78 the distance between the anchors 72 and 76 will
shorten. Correspondingly, when pushing the connecting unit inside
the remote energy source, the distance between the two anchors 72
and 76 increases. The guiding unit may also be a mechanical unit
that transfers a longitudinal (or rotational movement, see below)
into a movement in a perpendicular direction of the unit 54. Thus
the reciprocating up and down cardiac assist movement of the MV
plane 48 is provided.
[0082] Turning to FIG. 11b, an embodiment of the type described
with reference to FIG. 11a is shown, except that the CS or GCV
anchor 82 is designed for more than one anchor in side branches 44.
In this manner, advantageous improved efficiency of the cardiac
assist device may be provided. Geometric distribution of the
supporting force may be provided that is advantageous for the
cardiac structures in a long term use of the device.
[0083] The FIGS. 12a and 12b show examples of configurations
described in FIGS. 7, 8 and 9 where electromagnets are used as
anchors. Different combinations of electromagnets and classical
permanent magnets will not be described in separate figures as they
would be apparent for the skilled person when reading the present
application. In FIG. 12a the first anchor is located in a side
branch 44 from the CS or the GCV and in FIG. 12b in the anterior
inter-ventricular vein (AIV).
[0084] Still another embodiment of the innovation is depicted in
the FIGS. 13, 14, 15 and 16. Instead of pulling and pushing the
extension 54, the mechanical force is instead transferred by means
of rotation of the extension unit 54. Now the distal anchor 73 of
the device is not located in a side branch. Instead, it is placed
in the distal GCV 12 itself or in its continuation, the anterior
inter-ventricular vein 42. This embodiment takes advantage of the
fact that the three dimensional shape of the CS and the GCV
represents a loop from behind the heart, around the left angle of
the heart to its front surface. The loop is substantially oriented
in the mitral valve plane 48, see e.g. FIG. 2b. The extension unit
54 is an elongate loop shaped unit, distally ending at the distal
anchor unit 73, where it is attached to the distal anchor unit 73,
see e.g. FIGS. 15a-c. Hence, the loop shaped extension unit 54 may
be suitably actuated to move the CS and/or the GCV in direction to
and/or from the LV apex 26. As the MV is connected by cardiac
tissue to the CS and GCV, a movement of the extension unit 54 is
transferred to the MV plane 48.
[0085] In FIG. 13 the part of the extension 54 that is located
inside the CS and the GCV, here numbered with 55 is depicted. The
device has different operative positions, as shown in FIGS. 13a-c.
In the neutral position, depicted in FIG. 13a, we have a
perpendicular view of the loop that will appear as a straight line
from that angle. Compare also the view in FIG. 15a.
[0086] A distal anchor unit 73 is located at the front of the
heart. Most preferable the distal anchor unit 73 is made of a stent
design. A second anchor 75 is arranged proximally of the distal
anchor 73 in the GCV or preferably in the CS as close to the ostium
6 (FIG. 1) as possible. The second anchor is preferably made of a
stent design. Additional anchors 77 may be located for support
anywhere between the distal end anchor 73 and the proximal end
anchor 75, see e.g. FIG. 14. The additional anchors are preferably
made of a stent design.
[0087] The extension unit 54 is proximally connected to a
mechanical actuator that controllably rotates the extension unit 54
synchronized with the cardiac cycle. In the embodiment, the
extension unit 54 is proximally connected to the remote energy
source 84. However, other arrangements and locations of the
mechanical actuator providing the rotational movement of the
elongate extension unit 54 may be provided in other embodiments.
The mechanical actuator may for instance be arranged
intra-cardiac.
[0088] While rotating the extension unit 54 clockwise (seen from
the mechanical actuator, here the remote energy source 84 end), as
shown in position b in FIG. 13, the loop 55 flexes towards the LA
14, moving the CS and the GCV also in this direction. Since the CS
and the GCV are so closely related to the MV, such a backwards
movements in relation to the LV apex will augment the normal
upwards movement of the MV in diastole if the clockwise rotation is
done in diastole.
[0089] In analogy to this, a counter-clockwise rotation in systole
will augment the downwards movement of the closed MV (piston) in
systole, as depicted in FIG. 13, position c).
[0090] In FIG. 14 it is also illustrated that there in addition may
be a retention unit 79 that locks the extension unit 54
longitudinally to stay at the location of the proximal anchor unit
75. The retention unit may be a tube or loops located in the
anchors allowing the extension 54 to rotate, but will prohibit
axial movements in order to prevent dislocation of the extension
units 54 and 55. Extension units 54 and 55 may be in one integral
piece or have different segments that are articulated (not shown).
The number of segments and articulation may be suitably chosen in
order to design stiffness or flexibility necessary to accommodate
the device in place while still being functional.
[0091] FIG. 15 illustrates in more detail the embodiment taking
advantage if rotating a loop in an anatomical environment. FIG. 15a
depicts the neutral position. In FIG. 15b the extension units 54
and 55 are rotated clockwise. Now the loop of 55, the CS, the GCV
and the mitral valve move up towards the LA in diastole. In FIG.
15c the extension units 54 and 55 are rotated counter-clockwise and
the loop of 55, the CS, the GCV and the mitral valve moves down
towards the LV apex in systole.
[0092] The direction of the MV plane movement, here related to the
rotation, is controlled, e.g. based on ECG detection, and in
synchronisation with the cardiac cycle. A control unit operatively
connected to implement the control is provided, as described in an
example below. The control unit may be implemented in the remote
energy source unit 84.
[0093] Further, in another embodiment, in addition to the
rotational movement, a longitudinal movement of the extension unit
54 may be added. By pulling the extension unit 54, attached to the
distal anchor 73, relative to the sheath 78, that now is fixed to
the proximal anchor 75, the distance between anchors 73 and 75 may
be reduced. This additional transversal controlled movement may in
some embodiments include moving the lateral LV in the heart in a
reciprocating movement during systole towards an inter-ventricular
septum of the heart and during diastole away from an
inter-ventricular septum for assisting the pump action of the heart
along the short axis of a LV of a heart. In FIG. 15d it is
illustrated that in diastole the extension unit 54 is moved
distally relative to the sheath 78, in addition to the clockwise
rotation. The length of the connecting extension unit portion
between the proximal and the distal anchor is thus extended. Thus,
the outwards movement of the lateral LV wall is augmented relative
to the intra-ventricular septum. In Systole on the other hand, as
shown in FIG. 15e, the extension unit 54 is moved proximally
relative to the sheath 78, the distal anchor 73 is pulled closer to
the proximal anchor 75, in addition to the counterclockwise
rotation. The length of the connecting extension unit portion
between the proximal and the distal anchor is thus shortened. Thus,
the inwards movement of the lateral LV wall is augmented relative
to the intra-ventricular septum. The direction of the LV lateral
wall movement, here related to the pulling and pushing in addition
to the rotation, is controlled, e.g. based on ECG detection, and in
synchronisation with the cardiac cycle. A control unit operatively
connected to implement the control is provided, as described in an
example below. The control unit may be implemented in the remote
energy source unit 84. The coronary sinus implant of embodiments
may thus be adjusted during at least a portion of a single cardiac
cycle. Adjustment is made instantaneously upon actuation. In
alternative embodiments, the short axis support actuation may be
made based on other units and actuating principles, including
electric or magnetic actuators, etc. In addition, the medical
device may have a plurality of sections which are individually
adjustable in length by an actuating unit, controlled by said
control unit arranged to controllably change said shape of said
sections individually. For instance, embodiments of the device may
comprise anchoring units between each of said plurality of
sections, wherein the length of the sections is adjustable e.g. by
pulling together or pushing apart distal and proximal anchoring
units of a section.
[0094] In another embodiment the inherent force of a spring is
utilized shown in FIGS. 16a and 16b. Here the extension unit 55 is
inserted and detached in the CS and the GCV or in the AIV.
Preferably the extension 55 in this embodiment has fix attachments
to the distal and proximal anchor units 73, 75. The cardiac assist
device is provided as a resilient unit. In this embodiment, the
cardiac assist device is provided in a relaxed position in the MV
plane up position. The relaxed position of the unit is spring
loaded against a MV plane down position. The loop 55 of the
extension unit 54 has as a default preferred state the relaxed
position. The extension unit thus forces the CS, the GCV and the
mitral valve to move up towards the LA, both in diastole and in
systole, namely against the spring load force. The inherent spring
load force is chosen to be less than the MV plane downward force
provided by the LV muscle. Thus, in systole, the cardiac muscle
force of the LV will be stronger than the inherent spring force of
the extension 55 and bring the loop down towards the LV apex in
systole. Such a device thus assists during the diastole when it
increases the LV diastolic filling by forcing the open MV up
against the blood stream further in the direction of the LA. On the
other hand, the resilient unit may have a relaxed position in a
lower MV plane position spring loaded against a MV plane up
position, such that the cardiac relaxation force of the LV brings
the loop to the up position, and the resilient unit assists during
the systole by assisting the LV systolic contraction by forcing the
closed MV down towards the LV apex.
[0095] Such non-powered devices might be made of Nitinol, a memory
shape metal or stainless steel or any other suitable material,
preferably metal. A control unit or remote energy unit 84 are
omitted in these particular embodiments. The action may be delayed
by integrating resorbable material, in the device in order to delay
its action and allow the device to grow in before its action is
initiated while the resorbable material disappears. Such material
could be for instance be PLLA, Polyvinyl or Polylactid or other
resorbable materials.
[0096] Alternatively, or in addition, the cardiac assist system may
be provided as a bistable system. Here, the diastolic up position
and the systolic down position of the MV plane may be provided as
equilibrium states of the system. Energy is either provided from
the external energy, or from the LV muscle source to initiate the
system to move between the two stable positions. These embodiments
may be more energy efficient than others.
[0097] In embodiments the cardiac assist device has a control unit
and a sensor for measuring physiological parameters related to the
cardiac cycle activity providing a sensor signal. The sensor signal
is provided to the control unit which controls the displacement
unit to provide the movement by energy from an energy source and
based on the sensor signal. The cardiac assist device operation is
thus controlled in synchronicity with the heart action. The sensor
may be an ECG electrode or in addition or alternatively be based on
detecting other physiological parameters related to the cardiac
activity, such as a blood pressure wave, blood flow patterns, or
acoustic signals of the cardiac activity.
[0098] A remote energy source 84 as comprised in some embodiments,
is shown in FIG. 17. It has a battery section 86 and a computing
section 88 containing computer algorithms and chips. The computer
section 88 has receiving electrodes or surfaces 92 connected, which
are able to detect an Electrocardiogram (ECG) signal. Based on the
ECG signal, the cardiac assist device operation is in embodiments
controlled in synchronicity with the heart action.
[0099] Such synchronicity may in addition or alternatively be
established by means of detecting other physiological parameters
related to the cardiac activity. Such parameters include a blood
pressure wave, blood flow patterns, or acoustic signals of the
cardiac activity.
[0100] Alternatively, or in addition, the assisted movement of the
cardiac assist device may be controlled according to a set sequence
of assisted movements of the MV plane that mimics the natural
cardiac cycle to optimize the cardiac assist function. Frequency,
speed, and duration of different pause times of the assisted
movement may be set in the sequence to mimic a natural or desired
movement. The different parameters, such as pause time duration of
the movement, may vary over any time interval, and may be set to
vary according to a repeating program. The sequence may be
programmed into the computing section/control unit 88 which
controls the force generating unit. The force generating unit may
then provide the assisted movement according to the set sequence.
Energy from an energy source 84 may thus be controllably provided
to the force generating unit according to the set sequence for
providing the assisted movement.
[0101] Alternatively, or in addition, the medical device may be
incorporated into an artificial pacemaker system controlling or
assisting the natural cardiac muscle function. For instance the
assisted movement of the cardiac assist device may be controlled
from a processing unit of a pacemaker. The pacemaker including the
processing unit may be implanted in a patient. The pacemaker
triggers heart muscle activity in a per-se known manner, e.g. via
leads connected to the cardiac tissue for artificially triggering
the cardiac activity. Triggering of the assisted movement of the
cardiac assist device may be controlled may be based on the
electrical triggering of the cardiac activity by the artificial
pacemaker system, which is already synchronized with the cardiac
cycle. Preferably a time delay is provided from triggering
electrical triggering of the heart muscle activity to the
triggering/activation of the assisted movement of the cardiac
assist device during a heart cycle. The amount of the time delay
may be optimized, depending on the transfer time of electrically
triggering the heart muscle activity and the resulting pump
function of the heart caused by the controlled heart muscle
contraction.
[0102] The remote energy source 84 may have a mechanical section
90, where rotational or linear motion may be transferred to
extension unit 54. Rotational movement may be transferred directly
from an electrical motor, or geared down in revolutions by a
gear-box. Rotational energy from an electrical motor may be
converted to linear movement, enabling pulling and pushing force to
a wire connecting unit 54 that is extending all the way to the
distal anchor position. Alternatively, or in addition, the
mechanical section 90 may contain other actuators. For instance one
or more strong electromagnets may be provided in an actuator that
alternately are able to provide pulling and pushing force to wire
connecting unit 54 that is extending all the way to the distal
anchor position.
[0103] Further, the pulling and pushing force from the remote
energy source 84 may also be achieved by means of a linear
accelerator in the mechanical section 90. Alternatively, or in
addition, the mechanical section 90 contains an actuator providing
pulling and pushing force to extension unit 73, e.g. a wire or
elongate flexible rod of carbon fibre, that is extending all the
way to the distal anchor position by means of electrically
alternately cooling and warming a Nitinol actuator as commercially
available from MICA Motor Company, Modern Motion,
www.migamotors.com. Finally, in other embodiments, the remote
energy source is without a significant mechanical section, instead
computer chips are distributing electricity from the battery
according to the physiological cardiac cycle related signal, e.g.
ECG signal, either to electromagnets in one or more of the anchor
units of the implanted cardiac assist device or to mini-motors or
linear actuators in a heart chamber or on the heart surface.
[0104] The remote energy source may have a rechargeable battery
that is charged by means of a wire 94 penetrating the skin and when
charging the battery connected to a charging device externally (not
shown). Charging might also be done wireless through the skin, e.g.
by means of electromagnetic coils transferring energy inductively.
The skilled person in the art may alter and design such charging
according to specific requirements and available actual
technology.
[0105] FIG. 18, and the following illustrations refer to explain a
delivery system that is part of a treatment kit, the medical
procedure of using the delivery system to deliver a cardiac assist
device, and a medical method for therapeutically enhancing the left
ventricular function of a patient permanently.
[0106] In some particular embodiments, the remote energy source is
located in the fatty tissue under the skin, adjacent to a vessel,
preferably a large vein. This allows for convenient access to the
heart. Alternatively, the energy source may be attached to the
clavicle (not shown) in order to prohibit dislocation of the same
when delivering mechanical energy to the cardiac assist device
inside the heart. A pocket or pouch 104 in subcutaneous tissue may
be created close to the actual access vessel, e.g. the subclavian
vein, see FIG. 18.
[0107] In FIG. 18 the heart is shown relative to the great vessels
and the skin surface. An introducer catheter 100 with a valve (not
shown) is penetrating the skin and enters a large vein, in this
case the subclavian vein 3, however any other large enough vein can
be used for access. Adjacent to the skin puncture site a pouch 104
may be created under the skin in the fatty tissue in order to
accommodate a remote energy source 84 (not shown). The energy
source may be attached to the clavicle (not shown) in order to
prohibit dislocation of the same when delivering mechanical energy
to the cardiac assist device inside the heart. A guide wire 102 is
advanced through the introducer catheter 100 to the right atrium 4.
By means of a guiding catheter 106 (first shown in FIG. 21) access
to the coronary sinus is obtained via the RA and the guide wire is
guided to the appropriate side branch of the coronary sinus vein
system. In addition to the guide catheter, the kit contains
delivery catheters where the different parts are loaded. FIGS. 19
and 20 show examples of delivery systems, however, only depicting
the principle of delivering the device. FIGS. 19 a-c show how a
push and pull system is delivered from the delivery system 98.
[0108] In FIG. 19a a delivery system for a cardiac assist device as
described above with reference to FIG. 10a is shown. The delivery
system comprises a delivery catheter 108 that has a distal anchor
72 loaded inside at the tip. A pusher tube 110 that has a smaller
outer diameter than the inner diameter of the delivery catheter may
be advanced axially forward inside the delivery catheter 108 in
order to push the anchor 72 out of the delivery catheter 108 at the
desired site. Alternatively, the delivery catheter 108 may be
retracted over the pusher catheter in order to deliver the device
without any axial movement. The distal anchor unit 72, here shown
as a self expanding stent, is attached to the extension unit 54 and
space is accommodated inside the delivery catheter for the
extension unit 54 to be able to extend until outside the patient,
see FIG. 19b. The pusher tube 110, accommodates a lumen for the
guide wire 102 that also is permitted to run through the anchor 72.
The distal anchor unit is released and expands such that it safely
anchors into the surrounding vessel tissue. Thus the distal anchor
is in place, having the extension unit 54 extending therefrom.
[0109] Once the first anchor is in place, a second delivery
catheter 116, shown in FIG. 19c is advanced over the extension 54
until the guiding unit 80 is aligned with the side branch in which
the distal anchor 72 is located. When holding the pushing catheter
110 still in this position and retracting the deliver catheter 116,
the anchor 76 may be exactly released with the guiding unit facing
towards the side branch. Another aid in placing the device exactly
is an X-ray marker 112 attached to the catheter in order to better
visualize the exact position of the catheter, e.g. by means of
fluoroscopy.
[0110] FIG. 20 depict positioning of a device where rotational
force is transferred to the coronary sinus. This delivery catheter
118 is similar to the one shown in FIG. 19, except that it may have
another lumen added in order to accommodate an extra guide wire
102. Any additional figures of the delivery systems accommodating
other embodiments are not provided, since it would show variations
that are apparent to the skilled person when reading the present
disclosure.
[0111] The FIGS. 21-25 illustrate the method 800 of inserting a
cardiac assist system for permanent heart function
augmentation.
[0112] The skin is penetrated and an introducer catheter 100 with a
valve (not shown) is introduced into a large vein, e.g. the
subclavian vein 3, in step 800. Any other large enough vein may be
used for access. A guide wire 102 is advanced through the
introducer catheter 100 to the right atrium 4. By means of a
guiding catheter 106 access to the coronary sinus is obtained via
the RA and the guide wire is guided to the appropriate side branch
of the coronary sinus venous system in step 810. FIG. 21a
illustrates the advancement of a guide wire 102 into a desired side
branch 44 by means of the guiding catheter 106.
[0113] In step 820, as illustrated in FIG. 21b, the distal anchor
72 is released by means of the delivery catheter 108 in the side
branch 44.
[0114] In step 830, as shown in FIG. 22, the proximal anchor 76 is
positioned at the opening of the side branch.
[0115] In FIG. 23 the positioning of a mini motor 70 by means of
the delivery catheter 108 is shown.
[0116] Finally, as shown in FIGS. 24a and b, the positioning of a
rotation device is depicted. In FIG. 24a, it is shown how the guide
wire is advanced into the anterior inter-ventricular vein 42 by
means of the guide wire 102 and the guide catheter 106. In FIG. 24b
both anchors are depicted in place, showing the loop 55. An
additional guide wire may be accommodated through a separate lumen
114 (in FIG. 20 c).
[0117] In step 840, adjacent to the skin puncture site a pouch 104
is created under the skin in the fatty tissue in order to
accommodate a remote energy source 84 (not shown). In step 850, the
energy source may be attached to the clavicle (not shown) in order
to prohibit dislocation of the same when delivering mechanical
energy to the cardiac assist device inside the heart.
[0118] Once both anchors are securely attached, the extension unit
54 is adjusted in length and attached to the remote energy source
84 in step 860, and the system may be activated in step 870. The
remote energy source has a unit to detect the natural action of a
heart, e.g. based on an electrocardiogram, a blood pressure wave,
acoustic heart activity, or blood flow. The remote energy source
may thus provide energy for the distance change between the two
anchors in synchrony with the natural heart cycle, thereby
enhancing the natural up and down movement of a mitral valve during
a heart cycle.
[0119] A method is provided for permanently enhancing left
ventricular pump function of a heart of a patient, the method
comprising controlled assisted mitral valve plane movement
synchronized with a cardiac cycle of the heart.
[0120] Concurrently filed patent application titled "A DEVICE AND A
METHOD FOR AUGMENTING HEART FUNCTION" claiming priority to U.S.
Provisional Application Ser. No. 61/317,631 filed Mar. 25, 2010,
and Swedish application Serial No. SE1050283-9 filed Mar. 25, 2010,
both entitled Device and a Method for Augmenting Heart Function of
the same applicant as the present application, which all are
incorporated herein by reference in their entirety for all
purposes. This co-pending application discloses devices and methods
to intra-cardially move the mitral plane for augmenting the left
ventricular pumping effect. Embodiments of the present disclosure
may be combined with embodiments of the co-pending application. For
instance an annuloplasty ring may be provided as a mitral valve
intra-atrial or intra-ventricular anchor unit with a CS anchor unit
or driving unit as described above. Prosthetic MV may be provided
in combination with CS anchor unit or driving unit, etc. The MV
plane may advantageously be well mechanically and stable be
provided and moved more efficiently.
[0121] The present invention has been described above with
reference to specific embodiments. However, other embodiments than
the above described are equally possible within the scope of the
invention. Different method steps or a different order than those
described above may be provided within the scope of the invention.
The different features and steps of the invention may be combined
in other combinations than those described. Several actuating
principles may be combined with each other in certain embodiments,
e.g. a linear actuator and magnetic driving. The scope of the
invention is only limited by the appended patent claims.
* * * * *
References