AU2002212418B2 - Tubular support for setting, by percutaneous route, a substitution cusp - Google Patents

Abstract

The invention concerns a support (1) comprising a structure adapted to be radially contracted to enable the insertion of the support (1)/valve (2) assembly into the patient's body, and to be unfolded to enable said structure to be supported against the wall of the site to be equipped with the cusp. The invention is characterised in that the support structure comprises: an axial portion (3) supporting the cusp (2), having a thread or thread network structure adapted to be supported against the cardiac ring (10) remaining after removal of the deficient native cusp: at least an axial wedging portion (4), having a thread or thread network structure separate from the structure of said axial portion (3) of the cusp support, and with a diameter greater than the diameter of said axial portion (3) enabling it to be supported against the wall bordering said remaining cardiac ring (10); at least a thread (5) linking point-to-point said portions (3, 4).

Description

VERIFICATION OF TRANSLATION Australian application No.: I, Tuong TRAN of c/o Wordmaster Translations P/L, 19 High Road, Camberwell 3124 am the translator of the document(s) attached and I state that the following is a true translation to the best of my knowledge and belief of International patent application PCT/FRO1/03258 (WO 02/36048 Al) filed on 19.10.2001.

Australian application for: Dated: G 20 0 Signature of translator: O The present invention relates to a tubular support for positioning a N replacement heart valve, by a percutaneous route. It also relates to an Sinstrument for positioning the support.

The conventional technique for replacing a heart valve is open-heart surgery. This technique requires general anaesthesia, a broad approach, and stopping of the heart, which involves putting the patient under 00 extracorporeal circulation. It is therefore particularly awkward to implement and presents great operative risks to the patient.

The discussion of the background to the invention herein is included to explain the context of the invention. This is not to be taken as an admission that any of the material referred to was published, known or part of the common general knowledge as at the priority date of any of the claims.

In order to remedy this problem, the ablation of a defective heart valve by the percutaneous route, a peripheral valvular approach, has been envisioned. French Patent Application No. 99 14462 illustrates a technique and a device which can be used for this purpose.

With regard to positioning of a replacement heart valve, attaching the valve to a support with a structure in the form of a wire or network of wires, currently called a "stent", has been envisioned. The support can be contracted radially in such a way that it can be introduced into the body of the patient percutaneously by means of a catheter, and it can be deployed radially once it is positioned at the site that is to be equipped with the valve in order, thereby, to ensure placement of the valve. US Patent No. 5 411 552 illustrates a technique of this type.

The "stent" systems currently envisioned for the positioning of a heart valve introduce uncertainties of varying degree with regard to maintaining valves in position at the sites to be treated. In particular, the shape of known stents does not appear to be suited to sites in which the cardiac wall widens on both sides of the cardiac ring.

Furthermore, the cardiac ring remaining after ablation of the native valve can hinder the positioning of these stents.

These known systems also create problems related to the sealing quality of the replacement valve in certain cases. In effect, the existing O cardiac ring can have a surface which is to varying degrees regular and C calcified, which not only lessens the quality of the support of the stent against 0 this ring but also acts as a source of leaks between the valve and this ring.

Furthermore certain existing pieces of equipment present disadvantages with regard to their actual implantation. In particular, these pieces of equipment can not be moved after deployment of the support, even if their position is not optimal.

CIt would be desirable to remedy these significant problems.

It would be desirable that the invention provides a support ("stent") 010 that offers improved position maintenance after implantation.

It would also be desirable for the invention to provide a support that makes it possible to eliminate problems caused at the time of positioning of the replacement valve by native valve sheets, which are naturally calcified, thickened and indurated, or by residues of the valve sheets remaining after valve resection.

It would further be desirable for the invention to provide a support making complete sealing of the replacement valve possible, even in the case of existing cardiac rings which have surfaces which are to varying degrees irregular and/or calcified.

The invention also desirably provides a support whose position can be adapted and/or corrected if necessary at the time of implantation.

The support in question has a structure in the form of a wire or a network of wires which can be contracted radially in order to make the introduction of the support-valve assembly into the body of the patient by means of a catheter possible, and which can be deployed in order to allow this structure to support the wall of the site which is to be equipped with the valve.

According to the present invention, there is provided a tubular support for positioning a replacement heart valve, by a percutaneous route, the support having a structure in the form of a wire or a network of wires which can be contracted radially in order to introduce an assembly including the support and a valve into a body of a patient requiring heart valve replacement O by means of a catheter, and which can be deployed in order to allow the N tubular support to support a wall of a site to be equipped with the valve; wherein the tubular support includes: an axial valve support portion having a structure in the form of a wire or a network of wires, adapted to receive a replacement valve mounted thereon, and adapted to support any cardiac ring remaining after removal of 00 a defective heart valve from a patient; I- an axial wedging portion having a structure in the form of a wire or a network of wires, distinct from the structure of the axial valve support portion, and at least part of which has, in a deployed state, a diameter greater than a diameter of the axial value support portion in a deployed state, such that the axial edging portion is suitable for supporting a wall bordering an existing cardiac ring; and at least one wire connecting the axial valve support portion and the axial wedging portion, without obstructing deployment of the axial valve support portion and the axial wedging portion according to their respective diameters.

The invention thus provides a tubular support in the form of at least two axial portions (an axial valve supporting portion and an axial wedging portion) which are individualized with respect to one another with regard to their structure, which are connected in a localized manner by at least one wire; where this wire or these wires do not obstruct the variable deployment of the axial valve support portion and of the axial wedging portion(s).

The presence of a structure in the form of a wire or a network of wires in the axial valve support portion makes possible a perfect assembly of a valve with this structure, and the shape as well as the diameter of the axial valve support portion can be adapted for supporting the existing cardiac ring under the best conditions. In particular, this axial valve support portion can have a radial force of expansion such that it pushes back ("impacts") the valve sheets which are naturally calcified, or residues of the valve sheets after valve resection, onto or into the underlying tissues, so that these elements do not hinder positioning of the replacement valve. This structure also makes it possible to support possible anchoring means and/or possible O sealing means in the space existing between the cardiac ring and the C replacement valve, as indicated below.

0 The form and/or diameter of each axial wedging portion can be adapted for supporting a cardiac wall situated at an approach to an existing cardiac ring under best conditions. In particular, the axial wedging portion can have a tubular shape with a constant diameter greater than that of the 00 axial valve support portion, or the form of a truncated cone whose diameter Cincreases with distance from the axial valve support portion.

Preferably, the tubular support has an axial valve support portion in the form of at least two parts, of which at least one is suitable for supporting the valve and of which at least another is suitable for pushing back the native valve sheets, or residues of the native valve sheets after valve resection, into or onto the adjacent tissue in order to make this region able to receive the tubular support.

This axial valve support portion eliminates a problem generated by these valve or cardiac ring elements at the time of positioning the replacement valve. The radial force of this axial valve support portion, by impacting all or part of the valvular tissue or in the wall or its vicinity in effect ensures a more regular surface more capable of receiving the valve support axis. It also ensures a better connection with the wall while reducing the risk of peri-prosthetic leakage.

Specifically, in order to support the valve, the axial valve support portion can have a part in the form of an undulating wire with large-amplitude undulations, and a part in the form of an undulating wire with small-amplitude undulations, adjacent to said part with large-amplitude undulations, having a relatively great radial force in order to make it possible to push said valvular tissue against or into the wall of the passage.

Preferably, the tubular support according to the invention has two axial wedging portions, one connected to an axial end of said axial valve support portion and the other to the other axial end of this same axial valve support portion.

These two axial wedging portions thus make it possible to wedge the support on both sides of an existing cardiac ring, and consequently makes O possible complete wedging of the tubular support in two opposite directions C with respect to a treated site.

SIf necessary, for example, in the case in which a passage with a valve has an aneurysm, the support according to the invention includes: an axial holding portion, suitable for supporting in a deployed state a wall of a passage, and 00 connecting wires such as the aforementioned connecting wires, Cconnecting said axial valve support portion and said axial holding portion, these wires having a length such that the axial holding portion is situated after implantation a distance away from the axial valve support portion.

This distance allows said axial holding portion to rest against a region of a wall of a passage not related to a possible defect which may be present at an approach to a valve, particularly an aneurysm. The length of the connecting wires can also be calculated in order to prevent the axial holding portion from coming into contact with ostia of coronary arteries.

The aforementioned axial portions (valve support, wedging, holding portions) can have a structure in the form of an undulating wire, in zigzag form, or preferably a structure in diamond-shaped mesh form, the mesh parts being juxtaposed in the direction of the circumference of these portions.

This structure allows a suitable radial force making it possible to ensure complete resting of said portions against a wall which receives them.

The tubular support according to the invention can be produced from a metal that can be plastically deformed. The instrument for positioning of the tubular support then includes: -a balloon which has an axial portion with a predetermined diameter, adapted for realizing deployment of said axial valve support portion; and at least one axial portion shaped so as to have, in an inflated state, a greater cross section than that of a passage to be treated, in such a way as to produce expansion of an axial wedging portion placed on it until the axial wedging portion encounters a wall which it is intended to support.

The tubular support according to the invention can also be produced from a material with shape memory, such as a nickel-titanium alloy of the type known as "Nitinol," which can be contracted radially at a temperature O different from that of a body of a patient and which regains its original shape CI when its temperature approaches or reaches that of a body of a patient.

According to another alternative, the tubular support may be produced from a material with shape memory but that can be plastically deformed, or has parts made from a material with shape memory and parts made from a material that can be plastically deformed, and is formed in such a way that it can be brought, by shape memory or plastic deformation, from a state of I contraction to a stable intermediate state of deployment between the state of contraction and a state of total deployment, and then by plastic deformation 010 or shape memory respectively, from said intermediate state of deployment to said state of total deployment; wherein in said intermediate state of deployment, the support has dimensions such that it remains mobile with respect to a site to be treated.

The support is thus brought to a site to be treated and then is deployed from its intermediate state. Its position can then possibly be adapted and/or corrected, and then the support is brought to its state of total deployment.

Specifically, the aforementioned material with shape memory but that can be plastically deformed can be a nickel-titanium alloy of the type called "martensitic Nitinol" which can undergo plastic deformation by means of a balloon.

Advantageously, the tubular support according to the invention has an anchoring means suitable for insertion into a wall of a site to be treated, and is shaped in such a way as to be mobile between an inactive position, in which it does not obstruct introduction of the support into the body of the patient, and an active position, in which it is inserted into a wall of a site to be treated.

Complete immobilization of the support at a site is thus obtained.

In particular, this anchoring means can be in the form of needles and can be mounted on the support between retracted positions and radially projected positions.

Advantageously, the axial valve support portion has, at its exterior surface, a sealing means shaped in such a way as to absorb any surface irregularities at or near an existing cardiac ring.

O This sealing means can consist of a peripheral shell made from a N compressible material or a peripheral shell delimiting a chamber and having a a radially expandable structure, this chamber being capable of receiving an inflating fluid suitable for solidifying after a predetermined delay following introduction into said chamber. This sealing means can also include a material that can be applied between an existing cardiac ring and the axial 00 valve support portion, this material being capable of solidifying after a Cpredetermined delay following application. Specifically, in this case, this material is capable of heat-activation, for example, by means of a laser, through the balloon, or capable of activation by emission of light of predetermined frequency, for example, by means of an ultraviolet laser, through the balloon. Said sealing means can also be present in the form of an inflatable insert with a spool-shaped cross section in an inflated state, which can be inserted between an existing cardiac ring and the axial valve support portion. The spool shape allows this insert to conform to the best extent possible to adjacent irregular structures and to provide a better seal.

For proper comprehension of the invention, the invention is described below with reference to the appended drawings representing, as nonlimiting examples, several possible embodiments of the tubular support to which they relate.

Figure 1 is a view of the deployed structure of a support, according to a first embodiment of the invention; Figure 2 is a cross-sectional view of the support of Figure 1 in its deployed state, with the heart valve which it contains; Figure 3 is an end view of the support of Figure 1 in the deployed state; Figure 4 is an end view of the support of Figure 1 in the contracted state; Figure 5 is a view of a heart in partial cross section, on which a replacement heart valve has been positioned by means of a support according to the invention; Figure 6 is a view of a deployed structure of a support according to a second embodiment of the invention; Figure 7 is a view of a deployed structure of a support according to a 0 third embodiment of the invention; N Figure 8 is a view of a detail of a part of the structure of Figure 7 on an a enlarged scale; Figure 9 is a view of the support according to Figure 7 after positioning in a body passage with an aneurysm; Figure 10 is a view of a deployed structure of a support according to a fourth embodiment of the invention; CFigure 11 is a detailed view of a variant of the fourth embodiment featuring an anchoring hook which includes the support according to the fourth embodiment; Figure 12 is a view of the same detail as shown in Figure 11 in cross section according to line XII XII of Figure 11; Figure 13 is a view similar to Figure 11, with the structure in the expanded state; Figure 14 is a view similar to Figure 12, with the structure in this same expanded state; Figure 15 is a partial view of a portion of a structure of the support according to a fifth embodiment; Figure 16 is an enlarged view of a mounting region for a prosthetic valve on the portion of Figure Figure 17 is a partial view in longitudinal section of the support according to the first embodiment and of a calcified cardiac ring; Figure 18 is a view similar to Figure 17, according to a variant of the first embodiment; Figure 19 is a view similar to Figure 17, according to another variant of the first embodiment; Figures 20 and 21 are views similar to Figure 17, according to yet another variant of the first embodiment, in two stages of positioning of the support; Figure 22 is a view in longitudinal section of a balloon making possible the expansion of the structure of the support represented in Figures 7 to 9; Figure 23 is a view in longitudinal section of a balloon according to a variant of the embodiment shown in Figure 22, and O Figure 24 is a view similar to Figure 5, showing a heart in which a C replacement heart valve has been positioned by means of the support 0 according to a sixth embodiment of the invention.

For the sake of simplicity, the parts or elements of the different embodiments which are identical or similar from one embodiment to another are represented by the same reference numerals. Figures 1 to 4 represent 00 tubular support 1 for positioning, by percutaneous route, of replacement heart Cvalve 2.

The tubular support 1 includes median axial valve supporting portion 3, which contains valve 2, two extreme axial wedging portions 4 and wires 5 for connecting these portions 3 and 4, median portion 3 also includes peripheral shell 6 provided with anchoring needles 7 and shell 8 made of compressible material.

As is particularly apparent from Figure 1, each of portions 3 and 4 is formed with an undulating wire, and wires 5 connect pointwise the ends of the undulations of portion 3 to the end of an adjacent wave of portion 4.

Portions 4, seen in expanded form, have lengths greater than the length of portion 3, so that when the ends of the wires respectively forming portions 3 and 4 are connected in order to form the tubular support structure 1, the diameter of portion 3 is smaller than the diameter of portions 4.

The diameter of portion 3 is such that portion 3 can, as shown by Figure 5, support cardiac ring 10 that remains after removal of defective native valve, while portions 4 can support walls 11 bordering ring 10. These respective diameters are preferably such that said supporting operations take place with slight radial restraint of ring 10 and walls 11.

Portion 3 presents in a deployed state a constant diameter. Portions 4 can have a constant diameter in the form of a truncated cone whose diameter increases away from portion 3.

The entire tubular support structure 1 can be made from a material with shape memory, such as the nickel-titanium alloy known as "Nitinol." This material allows the structure to be contracted radially, as shown in Figure 4, at a temperature different from that of a body of a patient and to regain the original shape shown in Figures 2 and 3 when its temperature O approaches or reaches that of a body of a patient. The entire tubular c structure 1 can also be made from a material that can he expanded using a a balloon, such as from medical stainless steel (steel 316L).

Valve 2 can be made of biological or synthetic tissue. It is connected to portion 3 by sutures or by any other appropriate means of attachment. It can also be molded on portion 3.

oo Shell 6 is made of "Nitinol." It is connected to the undulations of c portion 3 at mid-amplitude, and has needles 7 at the site of its regions Sconnected to these undulations.

Needles 7 consist of strands of metallic wire pointed at their free Sends, which project radially towards the exterior of shell 6.

This shell can take on the undulating form which can be seen in Figure 4 in the contracted state of support 1 and the circular form which can be seen in Figure 3 in the deployed state of support 1. In its undulating form, shell 6 forms undulations 6a projecting radially on the outside of support 1, beyond needles 7, so that these needles 7, in the retracted position, do not obstruct the introduction of support 1 in a catheter or, once support 1 has been introduced into a heart using this catheter, do not obstruct deployment out of this support 1. The return of shell 6 to its circular form brings needles 7 to a position of deployment, allowing them to be inserted in ring 10 in order to complete anchoring of support 1.

Shell 8 is attached on shell 6. Its compressible material allows it to absorb any surface irregularities at or near ring 10 and thus to ensure complete sealing of valve 2.

Figure 6 shows a support structure 1 having a single portion 4 connected to portion 3 by wires 5. Portion 4 is formed by two undulating wires 14 connected together by wires Figure 7 shows a support structure I which has portion 3 and portion 4 connected by connecting wires Portions 3 and 4 have diamond-shaped mesh structures, these mesh parts being juxtaposed in the direction of the circumference of the portions and connected together at the site of two of their opposite angles in the direction of the circumference of the portions 3 and 4. Wires 5 are O connected to the structures in the region of the junction of two consecutive N mesh parts. The mesh parts also have anchoring hooks 7 extending a through them from one of their angles situated in the longitudinal direction of support 1.

Figure 8 illustrates, in an enlarged scale, the structure of this portion 4 and of a part of wires 5, as cut, for example, with a laser from a sheet of 00 stainless steel, and after bending of sharp ends 7a of hooks 7. These Chooks, in profile view, have the shape shown in Figures 12 or 14.

The structure represented in Figure 7 also has axial holding portion 010 20, which has a structure identical to that of portion 4 but with a coarser mesh size, and three wires 5 of significant length connecting this portion to portion 3. The wires 5, on the side of portion 20, have a single suture and on the side of portion 3, a double suture 5b. Their number corresponds to the three junctions formed by the three valve flaps of valve 2 which facilitates mounting of valve 2 on support 1 thus formed.

The support according to Figure 7 is intended to be used, as appears in Figure 9, when a body passage with a valve to be replaced, in particular an aorta, has an aneurysm at an approach to the valve. The length of wires connecting portions 3 and 20 is provided so that after implantation, portion is situated in a non-dilated region of said body passage, and portion 20 is provided so as to support a wall of a passage.

Figure 10 shows a structure similar to that of Figure 7 but unexpanded, except that the three wires 5 have a single wire structure but have an undulating wire 21 ensuring additional support near portion 3. This wire 21 is designed to support valve 2 with three valve flaps.

Figures 11 to 14 show an embodiment variant of the structure of portions 3, 4 or 20, when this structure is equipped with hooks 7. In this case, the structure has a zigzagged form, and each hook 7 has two arms 7b; each of these arms 7b is connected to the other arm 7b at one end and to an arm of structure 1 at its other end. The region of junction of the two arms 7b has bent hooking pin 7a.

Figure 15 shows portion 3 which has two undulating wires 25, 26 extending in the vicinity of one another and secondary undulating wire 27. As O represented in Figure 16, wires 25, 26 can be used to execute the insertion N of valve 2 made of biological material between them and the attachment of 0 this valve 2 to them by means of sutures 27.

Figure 17 shows a part of support 1 according to Figures 1 to 5 and the way in which the compressible material constituting shell 8 can absorb any surface irregularities at or near ring 10, which result from calcifications.

oo00 Figure 18 shows support 1 whose shell 6 has no compressible shell. A Cmaterial can then be applied, by means of an appropriate cannula (not represented), between ring 10 and this shell 6, this material being able to solidify after a predetermined delay following application.

Figure 19 shows support 1 whose shell 6 has a cross section in the form of a broken line, delimiting, on the exterior radial side, a lower shoulder.

Housed in the step formed by this shoulder and the adjacent circumferential wall is peripheral shell 8 which can be inflated by means of a catheter (not represented). This shell 8 delimits a chamber and has a radially expandable structure, such that it has in cross section, in an inflated state, two widened ends projecting on both sides of shell 6. This chamber can receive an inflating fluid that can solidify in a predetermined delay following its introduction into said chamber. Once this material has solidified, the inflating catheter is cut off.

Figures 20 and 21 show support 1 whose shell 6 receives inflatable insert 8 which has a spool-shaped cross section in an inflated state. This insert 8 can be inflated by means of catheter 29. Insert 8 is positioned in an uninflated state (Figure 20) at sites in which a space exists between shell 6 and existing cardiac ring 10. Its spool shape allows insert 8 (cf Figure 21) to conform as much as possible to adjacent irregular structures and to ensure a better seal.

Figure 22 shows balloon 30 making it possible to deploy support 1 according to Figures 7 to 9. This balloon 30 has cylindrical portion 31 whose diameter in an inflated state makes possible expansion of holding portion a cylindrical portion 32 of lesser diameter, suitable for producing expansion of portion 3, and portion 33 in the form of a truncated cone, makes possible the expansion of portion 4.

O As shown by Figure 23, portion 32 can be limited to what is strictly N necessary for deploying portion 3, which makes it possible to produce a balloon 30 in two parts instead of a single part, thus limiting the volume of this balloon Figure 24 shows support 1 whose median portion 3 is in two parts 3a, 3b. Part 3a is made of undulating wire with large-amplitude undulations, in order to support valve 2, and part 3b, adjacent to said part 3a and connected (to it by bridges 35, is made of undulating wire with small-amplitude undulations. Due to its structure, this part 3b presents a relatively high radial 010 force of expansion and is intended to be placed opposite ring 10 in order to push back the native valve sheets which are naturally calcified, thickened and indurated, or the residues of valve sheets after valve resection against or into a wall of the passage.

Axial portion 3a, 3b thus eliminates problems induced by these sheets or residual sheets at the time of positioning of valve 2.

It is apparent from the preceding that the invention provides a tubular support for positioning a replacement heart valve, by a percutaneous route, which provides, due to its portions 3 and 4, complete certitude as to maintenance of position after implantation. This support also makes possible a complete sealing of the replacement valve, even in case of a cardiac ring with a surface which is to varying degrees irregular and/or calcified, and its position can be adapted and/or corrected as necessary at the time of implantation.

It goes without saying that the invention is not limited to the embodiment described above as an example but includes all the embodiment variants within the scope of the appended claims.

Claims (24)

1. A tubular support for positioning a replacement heart valve, by a percutaneous route, the support having a structure in the form of a wire or a network of wires which can be contracted radially in order to introduce an assembly including the support and a valve into a body of a patient requiring 0_ heart valve replacement by means of a catheter, and which can be deployed in order to allow the tubular support to support a wall of a site to be equipped cwith the valve wherein the tubular support includes: an axial valve support portion having a structure in the form of a wire N or a network of wires, adapted to receive a replacement valve mounted thereon, and adapted to support any cardiac ring remaining after removal of a defective heart valve from a patient; an axial wedging portion having a structure in the form of a wire or a network of wires, distinct from the structure of the axial valve support portion, and at least part of which has, in a deployed state, a diameter greater than a diameter of the axial value support portion in a deployed state, such that the axial wedging portion is suitable for supporting a wall bordering an existing cardiac ring; and at least one wire connecting the axial valve support portion and the axial wedging portion, so as without obstructing deployment of the axial valve support portion and the axial wedging portion according to their respective diameters.

2. A tubular support according to claim 1, wherein the axial value support portion is in the form of at least two parts, of which at least one is suitable for supporting a valve and of which at least another is suitable for pushing back native valve sheets or residues thereof after valve resection, into or onto the adjacent tissue in order to adapt this region to receive the tubular support.

3. A tubular support according to claim 1 or 2, wherein at least one axial wedging portion has a tubular form of constant diameter greater than that of the axial valve support portion. O

4. A tubular support according to claim 1 or 2, wherein at least one axial C wedging portion has the form of a truncated cone with a diameter increasing a away from said axial valve support portion.

5. A tubular support according to any one of claims 1 to 4, including: an axial holding portion, suitable for supporting the tubular support in a deployed state against a wall of a passage containing the valve, and C- connecting wires, connecting said axial valve support portion and said axial holding portion, and having a length such that the axial holding portion is situated after implantation a distance away from axial valve support portion.

6. A tubular support according to any one of claims 1 to 5, wherein each axial valve support portion, axial wedging portion or axial holding portion has a structure in diamond-shaped mesh form, the mesh parts being juxtaposed in the direction of the circumference of the portion.

7. A tubular portion according to any one of claims 1 to 6, including two axial wedging portions, one connected to an axial end of said axial valve support portion and the other to the other axial end of the same axial valve support portion.

8. A tubular support according to any one of claims 1 to 7, which is made from a plastically deformable metal.

9. A tubular support according to any one of claims 1 to 7, which is made from a metal with shape memory, such as the nickel-titanium alloy known as "Nitinol", which can be contracted radially at a temperature different from that of a body of a patient and which regains its original shape when its temperature approaches or reaches that of a body of a patient.

A tubular support according to any one of claims 1 to 7, which is made from a metal with a shape memory but that is plastically deformable, or has O parts made from a material with shape memory and parts made from a C material that can be plastically deformed, which is shaped in such a way that 0 it can be brought, by shape memory or plastic deformation, from a state of contraction to a stable intermediate state of deployment between a state of contraction and a state of total deployment, and then by plastic deformation or shape memory, as the case may be, from said intermediate state of 00 deployment to said state of total deployment; wherein in said intermediate Cstate of deployment, the tubular support has dimensions such that it remains mobile with respect to a site to be treated.

11. A tubular support according to any one of claims 1 to 10, including anchoring means suitable for anchoring the tubular support after being inserted into a wall of a site to be treated, formed in such a way as to be moveable between an inactive position, in which the anchoring means does not obstruct introduction of the support into a body of a patient, and an active position, in which it is inserted in a wall of a site to be treated.

12. A tubular support according to any one of claims 1 to 11, wherein said axial valve support portion, has at its exterior surface a sealing means adapted to absorb any surface irregularities at or near an existing cardiac ring.

13. A tubular support according to claim 12, wherein said sealing means includes a peripheral shell made of a compressible material.

14. A tubular support according to claim 12, wherein said sealing means includes a peripheral shell delimiting a chamber and having a radially expandable structure, the chamber being capable of receiving an inflating fluid suitable for solidification after a predetermined delay following introduction into said chamber.

A tubular support according to claim 12, wherein said sealing means includes a material that can be applied between existing cardiac ring and the O axial valve support portion, the material being suitable for solidification after a C predetermined delay following application.

16. A tubular support according to claim 12, wherein said sealing means is an inflatable insert with a spool-shaped cross section in an inflated state, which can be inserted between existing cardiac ring and the axial valve 00 support portion.

17. An instrument for positioning a tubular support according to any one of claims 8 or 10 to 16, which includes balloon which has an axial portion with a predetermined diameter, suitable for executing deployment of said axial valve support portion, and at least one axial portion shaped in order to have, in an inflated state, a cross section greater than that of the passage to be treated, so as to execute deployment of the axial wedging portion placed on it until the axial wedging portion encounters the wall it is intended to support.

18. A method of replacing a defective native valve including the steps of: providing a tubular support according to any one of claims 1 to 16; collapsing the tubular support and valve to fit within a catheter; advancing the catheter to the defective native valve; deploying the tubular support and valve; and withdrawing the catheter, leaving the tubular support and valve to function in place of the defective native valve.

19. A method according to claim 18, wherein: the provided tubular support is according to claim said tubular support is brought, from a state of contraction to a stable intermediate state of deployment between the state of contraction and the state of total deployment, in which the tubular support has dimensions such that it remains mobile with respect to the site to be treated; and said tubular support is then brought from said intermediate state of deployment to said state of total deployment. O

20. A method according to claim 18, wherein: c the provided tubular support is according to claim 11; and a -deployment of said tubular support includes a step of bringing the Sanchoring means in to said active position.

21. A method according to claim 18, wherein: oO the provided tubular support is according to claim 12; and c -deployment of said tubular support includes a step of making said c sealing means absorb any surface irregularities at or near the existing cardiac ring of the valve to be replaced.

22. A method according to claim 20, wherein: the tubular support is according to claim 14; and deployment of said tubular support includes the steps of inflating said inflating fluid into said chamber and waiting for solidification in said chamber of said inflating fluid.

23. A method according to claim 20, wherein: the provided tubular support is according to claim 15; and deployment of said tubular support includes the steps of applying said material between existing cardiac ring and the axial valve support portion of the tubular support, and waiting for the solidification of said material.

24. A method according to claim 20, wherein: the provided tubular support is according to claim 16; and deployment of said tubular support includes the steps of inserting said inflatable insert between existing cardiac ring and the axial valve support portion, and inflating said inflatable insert. A tubular support according to claim 1 substantially as hereinbefore described with reference to any one of the drawings. O 26. A method of replacing a deficient native valve according to claim 18 as c hereinbefore described. O 5 Date: 16 February 2006 PHILLIPS ORMONDE FITZPATRICK 00 Attorneys For: Jacques Seguin