Note: Descriptions are shown in the official language in which they were submitted.
2113549
AN INTRAVENOUS DEVICE FOR PARTIALLY OR TOTALLY FLATTENING
A VEIN
FIELD OF THE INVENTION
The present invention relates to an intravenous
device, relating to the field of angiology and in
particular to the treatment of varicose veins, said
device enabling the lumen of the vein to be partially or
totally flattened.
BACKGROUND OF THE INVENTION
Traditionally, veins have been subjected to external
ligatures by means of stitches or clips. Some doctors
are of the opinion that placing springs on the outsides
of the veins prevents such veins dilating and prevents
the formation of varices. Others propose using
mechanical valves, of the non-return type, at the
sapheno-femural junction.
Known intravenous devices include filter type
devices for the vena cava or cylindrical endoprostheses
which are intended to maintain or reinforce the opening
of the venous lumen for grafts or shunts, i.e. bypasses
putting the arterial circuit into communication with the
venous circuit.
Proposals have already been made in document
FR 2 652 737 for a filter that is designed to be
installed in the inferior vena cava to retain therein
clots that could give rise to pulmonary embolism. That
filter is made from a remanent spring shaped in the form
of a spiral having three non-touching turns with the
middle turn being of larger diameter than the other two.
That filter gives rise to a certain amount of flattening
in the vena cava in which it is installed; but because of
its shape comprising three non-touching turns, it is not
plane when in position in a vein, thus preventing any
significant obstruction of the lumen of the vein, blood
flow merely being split into six semicircular segments.
When the lumen of the vein is to be genuinely
obstructed, present practice is to use voluminous objects
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such as balloons or cylinders which can be felt through
the skin and which run the risk of migrating and of
giving rise to highly inflammatory thrombosis.
OBJECTS AND BRIEF SUMMARY OF THE INVENTION
The object of an aspect of the invention sought by
the Applicant is to propose an intravenous device that
mitigates the drawbacks of the devices mentioned above in
that it makes it possible to obstruct the lumen of a vein
partially or completely without any risk of migration or
of thrombosis.
This object of an aspect of the invention is
completely achieved by the intravenous device of the
invention.
In accordance with another aspect of the present
invention, there is provided an intravenous device for
partially or totally flattening a vein, wherein the
device comprises at least two presser rods that are
interconnected by at least one spring-forming spreader
element, said presser rods being suitable for bearing
against a respective one of two opposite borders of a
vein, thereby moving the borders apart, and wherein the
device is substantially planar when it is in position in
a vein, said rods being substantially parallel.
The device of the invention is clearly distinguished
from the obstruction device of Document FR 2 608 408
since that device does not possess any presser rods that
are substantially parallel when in the in-use position,
and it is not designed to spread out a vein but rather to
obstruct it by progressively building up an aggregate
from the blood flow.
The Applicant has taken advantage of the observation
that a vein, which is a collapsible tube, has a preferred
flattening plane which, in the case of a superficial vein
CA 02113549 2003-04-16
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for example, is parallel to the surface of the skin.
Recently, venous endoscopy has made it possible to define
four component elements of a vein, for example the
saphenous vein, namely an inner or deep "wallside" or
face, an outer or superficial face, and two borders
uniting the two faces. Below in the present application,
the term "border of a vein" is used to designate one or
other of said two elements.
At a valve, the borders of the vein are in the form
of commissures, constituted by the union of the cusps.
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Valvular clearance and speed of blood circulation
are improved by ovalizing the lumen of the vein.
Thus, when the intravenous device of the invention
is placed inside a vein, it substantially occupies a
plane which, if the vein is a superficial plane, is
parallel to the skin, i.e. it complies with the axis of
preferred flattening of the vein. The spreader element
causes it to urge the two borders of the vein away from
each other, and consequently tends to move the inner and
outer faces of the vein towards each other.
It will be understood that the thrust area
corresponding to the zone of contact between the presser
rods and the inside wall of the vein must be large enough
to avoid any risk of tearing and perforation, given the
fragility of venous tissue.
All sorts of spring effect spreader elements may be
used, providing they are capable of lying substantially
in a plane between the presser rods when the device has
been put into place in a vein.
In one embodiment, the spreader element is X-shaped
and comprises four presser rods disposed at the four ends
of said element.
In another embodiment, the spreader element includes
portions, preferably flattened portions, suitable for
acting as presser rods. Naturally, in this case, the
portions suitable for acting as presser rods must be
substantially rectilinear. For example, the device may
have the form of an elongated ellipse and the two presser
rods may be constituted by the facing portions that are
substantially parallel to the major axis.
In another example, the spreader element consists in
a sinusoidal spring wire having flattened vertices
forming the presser rods.
In another example, the spreader element consists in
a V-shape spring with the free ends of the branches of
the V-shape acting as presser rods.
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Advantageously, the intravenous device of the
invention includes anchor elements, in particular
situated on all or part of the presser rods. These
elements must enable the device to be locked in position
relative to the inside wall of the vein and to prevent
any migration of the device.
Advantageously, the presser rods are slightly
corrugated so as to increase their area of contact with
the wall of the vein, and thus increase their anchoring
capacity.
When the presser rods and the spreader element are
independent from each other, the spreader element is
fixed to the presser rods by welding or by means of
joints, e.g. of the hinge type.
Advantageously, the intravenous device of the
invention is fitted with adjustment means, serving
firstly to enable it to be adapted to the inside diameter
of a vein, and secondly enabling the desired degree of
flattening of the vein to be determined. Given these
adjustment means, it is possible to use a single device
either to partially flatten or ovalize a vein or else to
completely flatten or obstruct the vein.
In a particular embodiment, the spreader element is
in the form of a lozenge and the adjustment means are
constituted by a worm screw or rack system placed along
the longitudinal axis of the lozenge.
The intravenous device of the invention is
substantially plane when it is in position inside a vein.
Which is to be understood as meaning that it is
accurately plane when the spreader element lies
accurai:ely in the same plane as the presser rods.
Nevertheless, it is considered as being substantially
plane providing all or a part of the spreader element
lies at a small distance from the plane that is formed by
the presser rods. In particular, this is obtained in the
case of a device that is H-shaped having at least one
curved crossbar situated above the plane formed by the
CA 02113549 2003-04-16
presser rods. The H-shaped device preferably has two
curved crossbars that curve in opposite directions, one
being situated above and the other below the plane formed
by the presser rods. Under such circumstances, the two
5 crossbars delimit a substantially oval passage through
which blood can flow inside the vein. This shape
corresponds to the vein being partially flattened, with
the two crossbars preventing the inner and outer faces of
the vein coming together, and thus preventing the vein
being completely obstructed.
This particular embodiment is preferably used when
it is desired to fill the intercorneal space of the
valves and to reinforce the tensioning arc function of
the valvular thickening. Under such circumstances, the
concave curvature of the crossbars is designed so as to
fit closely to the shape of the two valvular thickenings.
Advantageously, at least one of the rods or the
spreader element is made of a material suitable for
containing and diffusing medicinal substances.
Advantageously, the intravenous device of the
invention is made completely or in part of a material
that is resorbable.
In accordance with another aspect of the present
invention, there is provided an intravenous device
according to claim 1 wherein:
the intravenous device is made up of two distinct
assemblies, each of which is constituted by at least two
rods and a spreader element;
said assemblies have their spreader elements
connected together by means of a resorbable link;
the rods are provided with respective anchoring
means; and
the resorbable link is impregnated with a substance
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suitable for chemically sclerosing or sectioning the wall
of a vein.
211349
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BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood on
reading the following description of various embodiments
of an intravenous device for partially or totally
flattening a vein, the device including presser rods and
a spreader element substantially in the same plane, and
being shown in the accompanying drawings, in which:
Figure 1 is a view of a device in the form of an
elongated ellipse;
Figure 2 is a view of a device in the form of a
cross having two presser rods;
Figure 3 is a view of a device in the form of an H
with a single crossbar lying in the same plane as the
presser rods;
Figure 4 is a view of an H-shaped device having two
curved crossbars;
Figure 5 is a view of a device that is sinusoidal in
shape;
Figures 6A and 6B are two views of a device in which
the spreader element is V-shaped, the device being shown
in the relaxed state (Figure 6A) and in place in a vein
(Figure 6B);
Figure 7 is a view of an X-shaped device having four
rods:
Figure 8 is a view of a device whose spreader
element is in the form of a lozenge provided with a
device for adjusting spread; and
Figure 9 is a view of a device having two
dissociable assemblies for obstructing a vein.
MORE DETAILED DESCRIPTION
The intravenous device of the invention is intended
to perform partial flattening, i.e. to improve
ovalization of a vein when its ovalization is
insufficient, or else to perform total flattening, i.e.
to obstruct a vein.
It is known that the wall of a vein is not
circumferentially uniform and that the capacity of the
.-~ 2~135~~
vein for being flattened is preferential in a determined
plane, which plane is parallel to the surface of the skin
when the vein is a superficial vein. Thus, a given vein
wall can be defined as two faces united by two borders:
an inner or deep face directed towards the inside of the
body, an outer or superficial face directed towards the
skin, and two borders uniting said two faces.
The device of the invention must be capable of being
used to remedy or take action in the event of misfunction
of the wall of a vein.
The means implemented in the device serve to move
the two borders of the vein further apart to some extent,
and consequently to move the inner and outer faces
towards each other. Such movement towards each other can
lead either to improved ovalization of the lumen of the
vein, or else, optionally, to the two faces of the vein
being moved all the way towards each other, thereby
obstructing the lumen of the vein.
The means implemented consist in at least two
presser sods 1 and 2 that are interconnected by a
spreader element 3.
When the device 4 is placed inside a vein, each of
the two presser rods 1 arid 2 is intended to bear against
a respective one of the two borders of the vein. The
spring-forming spreader element must exert a certain
pressure force on the two rods 1 and 2 so as to urge them
apart from each other and press them against the two
borders of the vein. Thus, when they are placed inside a
vein, the two rods 1 and 2 are substantially parallel.
The device 4 shown in Figure 3 is an example of a
very simple embodiment in which the spreader element 3 is
a metal wire. The device 4 is H-shaped, with the
spreader element 3 constituting the crossbar of the H-
shape and having a curved shape that occupies the same
plane as the two rods 1 and 2.
Spreaders of other shapes may be envisaged, e.g.
spreaders having the following shapes: i2, horseshoe-
~1
2113549
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shape, N, 7, T, cross-of-Lorraine, ladder, Y, Z, S,
triangle, or oval.
In Figure 7, there can be seen a device 5 which
comprises four presser rods 6 of smaller size and fixed
to respective ones of the four ends of the spreader
element 7 which is X-shaped.
In all of the examples described above, the presser
rods are assembled to the spreader element proper. Under
such circumstances, the rods are fixed to the spreader
element, in particular by welding or by joints, in
particular joints of the hinge type.
In order to simplify physical embodiment of the
device, it is naturally preferable for the device to be a
single piece and to have no fixing points between its
various elements. The three examples shown in Figures 1,
2, and 5 are single-piece embodiments of the device in
which the presser rods are constituted by portions of the
spreader element.
In Figure 1, there can be seen a device 8 which
consists in a metal ellipse of elongated shape, having a
length L along the major axis 11 of the ellipse. This
ellipse is remarkable in that parallel to the axis 11 it
includes two substantially rectilinear portions 9 and 10
that act as presser rods. The device 8 thus includes two
spreader elements 12 and 13 occupying the curved ends of
the ellipse interconnecting the portions 9 and 10.
In a particular embodiment, the device 8 was made
using a wire of chromium-cobalt in the ratio 40/60. The
wire was circular in section having a diameter of 0.3 mm
at its two curved ends 12 and 13 and flattened to be
substantially in the form of a 4 mm wide tape in its two
rectilinear portions 9 and 10 acting as presser rods.
When in position in a vein, the device 8 of Figure 1 had
a length L of 3 cm and a width 1 of 8 mm. In addition,
the portions 9 and 10 were provided with teeth 14
directed towards the outside of the ellipse so as to
anchor the device 8 in the wall of the vein.
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Figure 2 shows a device 15 comprising two rods 16
and 17 interconnected by an X-shaped spreader element 18.
Each of the rods 16 and 17 constitutes a rectilinear
extension of two lateral ends of the X-shape. Each of
the rods 16 and 17 is provided on its outside face
(i.e. its face directed towards the outside of the X-
shape), with an anchoring spike 19 placed substantially
two-thirds of the way along the length of said rod.
Figure 5 shows a device 20 in the form of a
sinusoid. The sinusoid is made using a metal wire. The
eight vertices 21 on either border of the transverse axis
22 of the sinusoid are flattened and constitute presser
rods of small size.
In all of the examples described above, the spreader
element lies exactly in the same plane as the presser
rods. Such versions are particularly suitable for
obtaining either ovalization or obstruction of the lumen
of a vein.
In the example shown in Figure 4, the device 23 is
suitable for ovalization only of the lumen of a vein and
is not suitable for obstructing a vein. The device 23 is
H-shaped, having two presser rods 24 and 25
interconnected by two crossbars 26 and 27. These two
crossbars 26 and 27 are curved. As shown in Figure 4,
one of them, 27, is situated above the plane of the rods
24 and 25, whereas the other one, 26, lies beneath said
plane. It will be understood that when the device is put
into place inside a vein, and the rods 24 and 25 are
pressed against the borders of the vein, then the two
crossbars 26 and 27 form a spreader element that defines
a thrcugh zone for the flow of blood and prevent the
inner and outer faces of the wall of the vein from coming
into contact with each other.
This particular version as shown in Figure 4 is
especially useful for performing valvular consolidation.
Under such circumstances, the crossbars 26 and 27 are
curved in such a manner that once the ends of the bars
2113549
to
have been placed in the intercorneal space, they fit
closely to the valvular thickenings. In this way, the
action o.f the presser rods when pushed apart from each
other by the spreader elements stretches the free borders
of the valves and reinforces the tensioning arc function
of the valvular thickenings.
The device 28 shown in Figure 8 includes adjustment
means enabling it to be adapted to the geometry of the
vein lumen or serving to determine the desired degree of
vein flattening. Said adjustment means are constituted
by a spreader element 29 in the form of a lozenge having
two opposite vertices 30 and 31 fixed to two presser rods
32 and 33, and having its other two vertices 34 and 35
provided with tapped holes. A threaded rod 36
interconnects the two vertices 34 and 35 and is fitted at
one of its ends with an adjustment screw 37. It is thus
possible to use the adjustment screw 37 to vary the
interior angle of the lozenge and thus to modulate the
tension force directed towards the rods 32 and 33 by the
spreader system 29.
The embodiment shown in Figure 9 relates more
specifically to sectioning or sclerosing a vein. This
device 38 comprises two assemblies 39 and 40 that are
interconnected by means of a link 41. Each of these two
assemblies 39 and 40 is U-shaped and the two assemblies
are connected together via their bases 42 and 43 which
also act as spreader elements with the branches of the U-
shapes acting as presser rods. Each of the branches is
terminated by an outwardly-directed hook 44 enabling the
device 38 to be anchored when it is put into place in a
vein. The two bases 42 and 43 are united by resorbable
catgut, impregnated with a substance for inducing
sclerosis.
When the device 38 is put into place in a vein,
diffusion of the sclerosis-producing substance sections
the vein, while the two elements 39 and 40 anchored on
either border of the sectioned zone ensure that the two
21I3~49
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ends of the sectioned vein remain in place. Naturally
the extension force applied by the bases 42 and 43 is
determined so as to achieve total flattening of the vein
and thus obstruction thereof at the sectioned ends.
In the embodiment shown in Figure 6A, the device 46
is V-shaped. It is constituted by two blades 47 and 48
that are secured against each other at the end 49, e.g.
by welding. Each blade 47 and 48 acts both as a spreader
element in a zone close to the common end 49, and as a
presser rod towards its free end, as can be seen by
examining Figure 6B which shows the said device 46 in
place inside a vein 50. The end portions 51 and 52 of
the two blades 47 and 48 are pressed against the borders
53 and 54 of the vein 50 and they push them apart under
the spring effect from the portions 55 and 56 close to
the common end 49. These portions 55 and 56 are
preferably paralleled by reinforcing blades.
The above embodiment is very flexible and insertion
thereof into a vein is facilitated by the fact that the
two blades can easily be folded together inside an
insertion catheter.
The device of the invention is put into place in the
same manner as is performed in the field of filters. It
takes place through a trocar or through a cut-down vein
(i.e. a vein that has been brought to the surface). A
catheter carrying ducts, hoses, optionally with
predetermined bending, and with or without a mandrel or
with or without a guide wire is inserted into a vein
until it reaches the location where the device is to be
released. In order to dispose the device so that its
general plane coincides with the direction of the two
borders of the vein, the distal end of the catheter may
be flattened or its inside surface may be grooved.
A pusher rod disposed inside the carrying catheter
is used for pushing out the device and releasing it
outside the catheter.
2113549
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It will be understood that the distal end of the
pusher rod must come into contact with the device in
order to achieve such expulsion. In order to improve the
orientation of the device while it is being released, the
distal end of the pusher rod may advantageously be shaped
so as to co-operate with the zone of the device that
comes directly into contact with said rod in such a
manner that rotation of the pusher rod causes
corresponding rotation of the device. For example, the
pusher rod may have a flattened lug at its end while the
facing zone of the device may include a slot
complementary to said lug. Thus, the distal end of the
pusher rod can penetrate into the device and rotate it,
after which it can be disconnected from the device merely
by the rod being withdrawn.
Similarly, for the embodiment shown in Figure 8, the
end of the pusher rod may contribute, once the device has
been put into place, to adjusting the spacing between the
presser rods. This can be done merely by providing the
adjustment screw 37 with a notch or slot in which the end
of the pusher rod can be received.
Naturally, the device may be released in the same
way as filters are released together with injections of
sclerosis-producing, anticoagulant, or other medicaments.
To facilitate such release, the catheter and the pusher
rod may have visible marks at their proximal ends outside
the patient, serving in particular to show the
orientation of the device close to their distal ends
inside said patient.
tnlhen the device includes anchor means, two push rods
are used to avoid said anchor means rubbing along the
inside surface of the carrying catheter.
The device of the invention may be made, completely
or in part, from materials that enable medicinal
substances to be diffused, e.g. anti-inflammatory
substances, sclerosis-producing substances, vaso-
,,
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constrictors, or other substances. A biological adhesive
or resin may be used.
Such a device may also be implemented, completely or
in part, by means of a resorbable material, such as
catgut.
The invention is not limited to the embodiments
described above by way of non-exhaustive example. In
particular, it may be implemented either in the form of a
single piece or it may be built up from a plurality of
elements, each of which elements may be made of a
different material, e.g. stainless steel, titanium, a
polymer material, ... . The materials used may have
shape memory or they may also have been subjected to
surface treatment in order to increase sclerosis
reactions, for example by using copper, or on the
contrary to increase biocompatibility, e.g. by means of
heparin-containing fluorocarbons.
In its spreader element, the device of the invention
may also include a ring or a hook for facilitating its
release or its recovery. In addition, it may include
means enabling it to be identified within the patient,
e.g. radio-opaque components, components having a high
echo-generating capacity, components that are colored to
show up well in venous endoscopy, or components that
conduct light for identification by cutaneous
translumination. The device of the invention for
providing partial or total flattening of a vein is
advantageous in the treatment of varices, venous
dilatation, angiomas, chronic deep venous insufficiency,
valvular consolidation, and sclerosis, without that list
being exhaustive.
