Vascular device for valve leaflet apposition

Vascular system for valve valve apposition

Background

Technical field

[0001] The present application relates to a vascular system comprising a balloon catheter and a vascular device, and more particularly but not exclusively, to a vascular device to approximate leaflets of venous valves in order to treat the insufficiency of the venous valves

Background of the related technique

[0002] The veins of the body carry blood to the heart and the arteries carry blood away from the heart. The veins have unidirectional valve structures in the form of leaflets arranged annularly along the interior wall of the vein, which open to allow blood flow to the heart and close to prevent return of flow. That is, when blood flows through the vein, the pressure forces the valve leaflets to separate as they flex in the direction of blood flow and move towards the inner wall of the vessel, creating an opening between them for blood flow. However, normally the leaflets do not bend in the opposite direction and, therefore, return to a closed position to prevent blood flow in the opposite direction, that is, retrograde, after the pressure is released. The structures of the leaflets, when they work correctly, extend radially inwards in the direction of mutual approximation, so that the tips come into contact with each other to block the blood backflow.

[0003] In the condition of insufficiency of venous valves, valve leaflets do not function properly to the extent that they thicken and lose flexibility, resulting in their inability to extend sufficiently radially inward to allow their tips come into sufficient mutual contact to prevent retrograde blood flow. Retrograde blood flow causes the accumulation of hydrostatic pressure in the residual valves and the weight of the blood causes the vessel wall to dilate. Said retrograde blood flow, which is commonly referred to as reflux, results in swelling and varicose veins, which causes considerable discomfort and pain in the patient. Such retrograde blood flow, if left untreated, can also cause ulcers of the skin and subcutaneous tissue due to venous stasis. In general there are two types of venous valve insufficiency: primary and secondary. Typically, the primary insufficiency of venous valves is a birth condition, in which the vein is simply too large in relation to the leaflets so that the latter cannot come into contact properly to avoid backflow. The secondary insufficiency of venous valves is more common, which is caused by clots that gel and heal, thus changing the configuration of the leaflets, that is, by thickening the valves which creates a "stump-like" configuration. Insufficiency of the venous valves can occur in the superficial venous system, such as the saphenous veins of the leg, or in the deep venous system, such as the femoral and popliteal veins that extend from the back of the knee to the groin. .

[0004] A common method of treating venous valve insufficiency is the placement of an elastic stocking around the patient's leg, to apply external pressure to the vein, which forces the walls to move radially inward to force to the leaflets to be placed in apposition. Although the tight average is sometimes successful, it is quite uncomfortable, especially in hot weather, to the extent that the average must be constantly kept to keep the leaflets in apposition. The elastic stocking also affects the physical appearance of the patient, thus potentially presenting an adverse psychological effect. This physical and / or psychological discomfort sometimes results in the patient removing the stocking, which avoids proper treatment.

[0005] Another method of treatment has been developed to prevent discomfort of the socks. This method involves major surgery that requires the implantation of a cuff internally with respect to the body, directly around the vein. This surgery requires a large incision, which results in a long recovery time of the patient, scars and carries the risks, for example, anesthesia, inherent in the surgery.

[0006] Another invasive method of surgery involves the selective separation of the valvular leaflets, referred to as valvuloplasty. In one of the methods, sutures are used to bring the free edges of the valve cusp so that they come into contact. This procedure is complicated and has the same disadvantages of the major surgery described above.

[0007] Therefore, it would be advantageous to provide a method and a device for minimally invasive treatment of venous valve insufficiency, without the need for an external mean or an internal sleeve. Therefore, said device would avoid the physical and psychological discomfort of an external mean, while avoiding the risk, complexity and expenses of surgically implanted sleeves. Such a device would advantageously be inserted in a minimally invasive manner, that is, intravascularly, and would work in a manner that would effectively place the valve leaflets in apposition.

[0008] US-A-5609598 discloses a vascular device and an application catheter for the minimally invasive treatment of venous insufficiency.

Summary

[0009] According to the present invention, a vascular system is provided comprising:

a balloon catheter having an elongated shaft and an expandable balloon, the balloon being inflatable through the introduction of fluid through a swelling lumen (206); and

a vascular device mounted on the expandable balloon and composed of shape memory material and having a folded position and a memorized position, the vascular device being expandable to an expanded position to engage the vessel walls and being able to substantially return to the memorized position to move the walls radially inwards.

[0010] The vascular device may be expandable first to the memorized condition in response to its exposure to body temperature and may be subsequently expandable to the expanded position by balloon inflation.

[0011] The vascular device may be expandable to the expanded position to the extent that the device is exposed substantially simultaneously to body temperature and the balloon swells.

[0012] The vascular device may be connected to the balloon. The system may further comprise a pair of loop sutures that connect the vascular device to the balloon, the sutures being separable from the vascular device upon expansion of the balloon to a predetermined size.

[0013] In the folded position, an intermediate portion of the tubular member may include a plurality of longitudinal strips with a space between adjacent strips, the longitudinal strips being swung out upon expansion of the device.

[0014] The vascular device may include a plurality of longitudinal strips and may further include a substantially straight groove formed in each of the longitudinal strips in the folded position of the device, each groove being transformed to adopt a substantial rhombus shape when the device is move to an expanded first position.

[0015] The longitudinal strips may be connected by means of transverse ribs, the ribs being placed in substantial axial alignment.

[0016] The present invention overcomes the problems and defects of the prior art by providing an intravascular device that displaces the wall of the vessel adjacent to the venous valve radially inwardly in order to place valvular valves in apposition.

Brief description of the drawings

[0017] Hereinafter, preferred embodiment (s) of the present disclosure are described, with reference to the drawings, in which:

Figure 1 is a perspective view of a first embodiment of the vascular device that is part of the present invention, shown in the expanded configuration;

Figure 2 is a side view of the vascular device of Figure 1 in the expanded configuration;

Figure 3 is another side view of the vascular device in the expanded configuration, rotated 45 degrees with respect to Figure 2;

Figure 4 is a front view of the vascular device of Figure 1 in the expanded configuration;

Figure 5 is a perspective view of the vascular device of Figure 1, shown in the folded configuration for application within the vessel;

Figure 6 is a side view of the vascular device of Figure 1, in the folded configuration;

Figure 7 is another side view of the vascular device in the folded configuration, rotated 45 degrees with respect to Figure 6;

Figure 8 is a perspective view of an alternative embodiment of the vascular device that is part of the present invention, shown in the expanded configuration;

Figure 9A is a side view of the vascular device of Figure 8, shown in the expanded configuration;

Figure 9B is a side view similar to Figure 9A, except that it shows an alternative embodiment in which the coupling members to the vessels extend at an angle to the wall of the vessels;

Figure 10 is a perspective view of the vascular device of Figure 8, in the folded configuration for application within the vessel;

Figure 11 is a side view of the vascular device of Figure 8 in the folded configuration;

Figure 12 illustrates an insertion method of the vascular device of Figure 1, showing the application catheter inserted directly into the popliteal vein in an antegrade direction;

Figure 13 illustrates an alternative method of inserting the vascular device of Figure 1 through the jugular vein for retrograde insertion into the popliteal vein;

Figure 14 illustrates another method of insertion of the vascular device of Figure 1, showing the application catheter inserted through the right femoral vein for retrograde access to the popliteal vein;

Figure 15 illustrates yet another method of insertion of the vascular device of Figure 1, which shows a contralateral approach in which the application catheter is inserted through the left femoral vein for its advance around the iliac vein for insertion retrograde in the right popliteal vein;

Figure 16 shows a side view of the application catheter for the vascular device of Figure 1, with the vessel wall shown in section, illustrating the antegrade insertion of the application catheter into the popliteal vein;

Figure 17 is a view similar to Figure 16, showing the initial removal of the sheath in the direction of the arrow to partially expose the vascular device of Figure 1;

Figure 18 is a view similar to Figure 16, showing the vascular device of Figure 1 expanded into the vessel, upstream (with respect to blood flow) of the valve leaflets, after the sheath has been completely removed;

Figure 19 is a view similar to Figure 16, showing the vascular device of Figure 1 expanded by means of a balloon, so that the coupling members to the vessels penetrate and retain the vessel wall;

Figure 20 is a view similar to Figure 16, after the balloon has deflated and the catheter has been removed from the vessel, showing the vascular device returned to its original position by joining the vessel wall and placing the valve leaflets in apposition;

Figures 21A to 21C are cross-sectional views of the vascular device of Figure 1, showing its interaction with the vessel wall during application and placement, where

Figure 21A corresponds to the initial position of the vascular device of Figure 18, wherein the coupling members to the vessels have not penetrated the vessel wall (for reasons of clarity the balloon has been omitted);

Figure 21B corresponds to the position of the vascular device in Figure 19, wherein the balloon has swollen to radially expand the device to a second expanded position in order to allow the vessel coupling members to penetrate the wall of the glass; and

Figure 21C corresponds to the position of the vascular device of Figure 20, wherein the balloon has deflated and the device returns to the first expanded position by moving the vessel wall radially inward;

Figure 22 shows a side view of the application device for the vascular device of Figure 1, with the vessel wall shown in section, illustrating as an alternative, the retrograde insertion of the application device into the popliteal vein;

Figure 23 is a view similar to Figure 22, showing the initial removal of the sheath in the direction of the arrow to partially expose the vascular device of Figure 1;

Figure 24 is a view similar to Figure 22, showing the vascular device of Figure 1 expanded into the vessel, upstream of the valve leaflets, after the sheath has been completely removed;

Figure 25 is a view similar to Figure 22, showing the vascular device of Figure 1 expanded by means of a balloon so that the coupling members to the vessels penetrate and retain the vessel wall;

Figure 26 is a view similar to Figure 22, after the balloon has deflated and the catheter has been removed from the vessel, showing the vascular device returned to its original position by joining the vessel wall and placing the valve leaflets in apposition;

Figure 27 is a side view of an alternative embodiment of the vascular device in the expanded position, shown inside a vessel (the vessel wall is shown in section);

Figure 28 is a view similar to Figure 27, showing a balloon that expands the vascular device so that the hooks penetrate the vessel wall;

Figure 29 is an enlarged view of the hook of the device of Figure 27 embedded in the vessel wall;

Figure 30 shows a side view of the application catheter corresponding to the vascular device of Figure 1, with the vessel wall shown in section, illustrating as another alternative, the antegrade insertion of the application catheter into the popliteal vein for positioning the device vascular downstream of the valvular leaflets;

Figure 31 is a view similar to Figure 30 showing the initial removal of the valve in the direction of the arrow to partially expose the vascular device of Figure 1;

Figure 32 is a side view of an alternative embodiment of an application system having a fastener, the view similar to Figure 23 showing the vascular device expanded inside the vessel, upstream of the valve leaflets, after the sheath has been removed;

Figure 33 is a view similar to Figure 32, showing the vascular device of Figure 1 expanded by means of a balloon, so that the coupling members to the vessels penetrate and retain the wall of the vessel, and opening the support for the expansion of the ball; and

Figure 34 is a cross-sectional view of the vascular device of Figure 1, showing the attachment of Figure 32 expanded to the memorized position substantially simultaneously with the expansion of the balloon.

Detailed description of preferred embodiments

[0018] Referring in detail below to the drawings, in which the equal numerical references identify similar or equal components during all the various views, Figures 1 to 7 illustrate a first embodiment of a vascular device and Figures 8 to 11 illustrate a second embodiment of a vascular device. The devices, generally designated by numerical references 10 and 100, expand to engage the inner wall of the vessel and contract to pull the walls of the vessel radially inwards. When the vessel wall is pulled radially inwards, the valve leaflets inside the vessel are closer together to a functional condition.

[0019] Figures 1 to 4 illustrate the vascular device 10 of the first embodiment in the expanded configuration, and Figures 5 to 7 illustrate the vascular device 10 in the folded configuration. The vascular device 10 is composed of a shape memory material, such as a nickel-titanium alloy commonly known as Nitinol, so that, in its memorized configuration, it adopts the shape shown in Figure 1. This shape memory material features characteristically stiffness in the austenitic state and more flexibility in the martensitic state. To facilitate passage from the application catheter, the shape memory device is maintained in a folded configuration within an application sheath as described in more detail below, where it is cooled by a saline solution to maintain the device. below its transition temperature. The cold saline solution keeps the device temperature dependent in a relatively softer condition to the extent that it is in the martensitic state within the sheath. This facilitates the exit of the device 10 from the sheath since, otherwise, friction contact would occur between the device and the inner wall of the sheath, if the device were maintained in a rigid, i.e. austenitic, condition. When the device 10 is released from the sheath to the target site, it is heated by body temperature, thus making a transition, in response to this temperature change, to an expanded austenitic condition.

[0020] The device 10 is preferably formed from a tubular member, preferably by laser cutting. The device 10 includes a proximal portion 12, and intermediate portion 14 and a distal portion 16. In the expanded condition, the device 10 has four cells 17 with a substantially rhombus shape, which form substantially rhombic openings 18, in the proximal portion 12, and four cells 15 with a substantial rhombus shape that form substantially shaped openings 20 rhombus in the distal portion 16. The extreme regions 19 of the cells 18, and the extreme regions 21 of the cells 20 are folded out with respect to the plane of the rest of the cell, in a direction away with respect to the longitudinal axis of the vascular device 10. This makes possible more suitably that the coupling members to the vessels, which will be described later, are coupled to the vessel walls.

[0021] The intermediate portion 14 is formed with four substantially diamond-shaped cells that form substantially diamond-shaped openings 22 arranged around a 360 degree arc of the cylindrical tubular member 10, a longitudinal strip 24 extending therethrough for bisect each cell. In this way, four symmetrical bisected cells 23 are formed. Each longitudinal strip 24 has a vessel coupling member 28, which extends from the first to engage the vessel wall as will be described later. In the expanded condition, the longitudinal strip 24 is buckled radially outward, away from the longitudinal axis of the vascular device 10, to allow the central members 28 to be attached to vessels (to be described later) to engage the inner wall. of the glass and secure it.

[0022] The geometry of the vascular device 10 can also be seen in reference to the folded configuration of the vascular device 10 shown in Figure 5 to 7. As shown, the device 10 is in the form of a cylinder with a reduced diameter . Each longitudinal strip 24 has a clipped section 27 to form the vessel coupling member 28. The longitudinal strip 24 narrows progressively in terms of width "w" at its opposite ends 29 that connect to the frame. The longitudinal groove 30 on each side of the strip 24 is substantially straight and has enlarged regions 32 of the oval type at opposite ends. The outer wall 34 of each longitudinal groove 30, that is, the wall of the groove 34 further separated from the longitudinal strip 24, is attached to the outer wall 34 of an adjacent longitudinal groove 30 by the transverse rib 36. Each nerve 36 forms a vertex of a cell 15 and a vertex of a cell 17 when it expands. The cell openings 18 and 20 in the folded configuration, as shown in Figure 6, respectively have a narrowed elongated portion 20a, 18a, and a widened portion 20b, 18b with flared regions 20c, 18c, to form diamond-shaped openings having bent end regions 21, 19 when the device 10 expands. The flared regions 20c, 18c allow the formation of said folded regions 21, 19.

[0023] A vessel coupling member extends from the frame of each of cells 15 and 17. The vessel coupling member is preferably in the form of a hook with a penetrating tip and a beard.

[0024] More specifically, a vessel coupling member 40 extends outwardly and distally with respect to the frame of each of the four cells 15 in the distal portion 16 of the device 10. In the folded configuration of the device 10, each member 40 preferably extends generally parallel to the longitudinal axis of the vascular device 10 and substantially in the same plane as the corresponding nerve 36 at the opposite end.

[0025] Similarly, the vessel coupling members 42 extend outwardly and proximally with respect to the frame of each of the four cells 17 in the proximal portion 12 of the device 10. In the folded configuration of the device 10, each member 42 preferably extends generally parallel to the longitudinal axis of the vascular device 10 and in the same plane as the corresponding nerve 36 at the opposite end.

[0026] The four vessel coupling members 28, formed in the central (intermediate) portion 14 in the folded configuration, are substantially parallel to the longitudinal axis of the device 10 and in the same plane as the longitudinal strip 24 from the which is formed

[0027] Each of the members 28, 40 and 42 for coupling to vessels, are preferably in the form of a hook having a penetrating tip 29, 41 and 43 to pierce the wall of the vessel and a beard 31, 45 and 47 , respectively, to help retain the vessel wall. The sharp penetrating tips 29, 41, 43 penetrate the vessel wall in a radial direction and hold the vessel against axial movement with respect to the device 10; the beards 31, 45, 47 limit the radial movement of the vessel with respect to the device 10, whereby together they securely hold (hold) the wall of the vessel in relation to a radial inward movement that will be described later.

[0028] It should be understood that although four vessel coupling members 42, 40, 48 are described, extending from the proximal and distal cells 17, 15 and from the central longitudinal strips 24, respectively, a smaller number or greater than members of coupling to vessels provided they achieve the retention function of the vessel as described in more detail below.

[0029] When the vascular device 10 expands, members 28, 40 and 42 move to a shape memory orientation, bent out at an angle, preferably approximately 90 degrees, relative to the longitudinal axis "A" of the device 10, with regions 19 and 21 that bend out of the plane to increase the distance that the members can extend from the center to the vessel wall. The longitudinal strips 24 are buckled radially outward, and the members 28 bend outward at an angle, preferably approximately 90 degrees, relative to the longitudinal axis, to engage the vessel wall. Although 90 degree angles are shown, other angles are clearly contemplated. Note that, due to the geometry of the device 10, the tips on the outer edge are axially inward, shortening the length of the device, and the central strut (strip) 24 is buckled radially outward. The buckling extends the radial reach of the device 10. Note also that, in the expanded configuration, the tips of the vessel coupling members terminate substantially at the same distance from the longitudinal axis of the device 10. The length of the end hooks is preferably the same as the length of the center hooks; the bent regions 19, 21 accommodate the buckling of the strut 24. Due to the laser cut configuration, the foreshortening is reduced, that is, the reduction in device length in response to the expansion.

[0030] By way of example, for use, for example, in a 14 mm unhealthy dilated vessel, the length of the vascular device 10 in the folded configuration could be approximately 3 cm, and the external diameter approximately 3.5 mm . In the expanded memorized configuration, the length decreases to approximately 2.8 cm and the cross-sectional dimension increases to approximately 12 mm, 15.5 mm, if the 1.7 mm hooks are included. Note that the change in length is mainly due to the buckling strip and bent regions since the magnitude of foreshortening is minimized. These dimensions are provided by way of example to the extent that the present invention clearly contemplates other dimensions and a use in vessels of different sizes is also contemplated.

[0031] An alternative embodiment of the vascular device is shown in Figures 8 to 11, Figures 8 and 9 showing the device in the expanded configuration and Figures 10 to 11 showing the folded configuration for application in the vessel.

[0032] Returning first to Figures 10 and 11, the device 100 is preferably laser cut from a cylindrical tube, forming a series, for example, ten, of symmetrical longitudinal strips 102 ending at opposite ends with members 110, 112 coupling to vessels. Each strip 102 has a longitudinal groove 104 formed therein, which has a uniform width throughout its length. Adjacent strips 102 are joined by means of ribs or transverse struts 106, creating a gap 108, 109 on each side of the ribs 106 between strips

102 Consequently, the device can be considered such that it forms a centrally located column of grooves 104, with ribs 106 in axial alignment and grooves 104 in axial alignment.

[0033] The vessel coupling members 110 and 112 are preferably in the form of hooks, as described above in the first embodiment, each vessel coupling member 110 having a penetrating tip 114 and a beard 116, and having each member 112 a penetrating tip 118 and a beard 119. The penetrating tips 114 and 118 penetrate the vessel wall and prevent axial movement, while the beards 116, 119 limit radial movement. In the folded configuration, as shown, the vessel coupling members 110, 112 are substantially parallel to the longitudinal axis of the device 100, being in the same plane as the respective longitudinal strip 102.

[0034] As shown, the cylindrical tubular member is formed to obtain ten longitudinal strips 102 with ten hooks 110 at the proximal end 105 and ten hooks 112 at the distal end 107. Although at each end ten longitudinal strips and ten are shown. vessel coupling members, it should be appreciated that a smaller or larger number of longitudinal strips and vessel coupling members can be used. On the other hand, it is not necessary for all longitudinal strips to end in vessel coupling members, provided that a sufficient number of strips have vessel coupling members to properly secure the vessel.

[0035] The structure of the vascular device 100 is shown in its first expanded configuration in Figures 8 and 9. The vascular device 100, such as the device 10, is composed of a shape memory material, such as Nitinol, so that , in its memorized configuration, adopts the form shown in Figure 8. The shape memory device is maintained in a folded configuration within a sheath as described in more detail below, where it is cooled by a saline solution to keep the device below its transition temperature. When the device 100 is applied to the target site and released from the sheath, it is heated by body temperature, thus making a transition, in response to this temperature change, to an expanded austenitic condition. The maintenance of the device in its softened martensitic state, inside the sheath, facilitates its application in the vessel, since otherwise, friction contact would occur between the device 100 and the inner walls of the application sheath if the device was retained inside the sheath in its austenitic condition.

[0036] When they expand, the longitudinal grooves 104 form cells 120 with a substantial rhombus shape, with openings 122 with a substantial rhombus shape. Upon expansion, the vessel coupling members 110 and 112 extend at an angle, preferably approximately 90 degrees, with respect to the longitudinal axis of the vascular device 10 to allow the vessel coupling members 110 and 112 to engage the vessel wall and secure it (see, for example, Figure 9A). However, it is also contemplated that the vessel coupling members 110 ', 112' may extend at a different angle, for example, approximately 60 degrees, as shown in the alternative embodiment of Figure 9B.

[0037] When the device moves from the folded configuration to the expanded configuration, it is shortened in axial length as the diameter increases. For example, in one embodiment, the length of the vascular device 100 in the folded configuration is approximately 1.8 cm and the diameter is approximately 3.5 mm. In the expanded configuration, the length decreases to approximately 1 cm, mainly due to the hooks that fold upwards to the extent that foreshortening is minimized, and the diameter in the memorized expanded configuration is increased to approximately 12 mm (15 , 5 if 1.75 mm hook length is included). These dimensions are provided by way of example to the extent that other dimensions are clearly contemplated.

[0038] Returning to the method of using vascular devices, the insertion of the vascular device 10 will be described, it being understood that the vascular device 100 would be inserted in the same manner and expanded and retracted in the same manner as the device 10.

[0039] There are several different methods of insertion of the vascular device of the present invention, to treat the insufficiency of venous valves in correspondence with the popliteal or saphenous vein. Figures 12 to 15 illustrate examples of some of these approaches illustrating several access vessels for the application devices to reach these veins. In Figure 12, catheter 200 is placed in the popliteal vein "P" in the patient's leg "G" and advanced to a region adjacent to the "T" leaflets to deploy the vascular device upstream of the leaflets. Thus, the application catheter is applied in an antegrade manner, the tip extending downstream of the "T" leaflets to deploy the device just upstream (defined in reference to the direction of blood flow) of the leaflets.

[0040] In the approach of Figure 13, catheter 210 is inserted through the right jugular vein "J", where it will be advanced through the superior and inferior vena cava, passing through the iliac vein "I" , through the femoral vein "F", and even the popliteal vein "P" through the leaflets "L" in a retrograde manner, that is, opposite to the direction of blood flow. Thus, the application catheter 210 would extend through the leaflet region just upstream of the leaflets. In Figure 14, the catheter 220 is placed in the right femoral vein "F", where it will be advanced in a retrograde manner to the popliteal vein "P" according to the manner described above with respect to Figure 13.

[0041] In the contralateral approach of Figure 15, catheter 230 is inserted through the left femoral vein "H" where it will be advanced around the iliac vein "I" and through the left femoral vein "F "To the popliteal vein" P ".

[0042] Each of the application catheters 200, 210, 220 and 230 has respective tubes 202, 212, 222 and 232, with a stopcock 204, 214, 224 and 234 to control the infusion of saline solution through the catheter in order to keep vascular device 10 (or device 100) in the folded martensitic folded configuration for application. The swelling port 206, 216, 226 and 236 provides the infusion of fluid to swell the balloon that is mounted on the catheter shaft and positioned within the device 10. The outer sheath of the application catheter slides relative to the axis of the catheter. catheter to expose the vascular device. The 208, 218, 228 and 238 guide wire port allows the insertion of a conventional guide wire (not shown) to guide the application catheter intravascularly to the target site. A conventional access sheath or introducer (not shown) would be inserted through the skin and into the access vessel, and the respective application catheter would be inserted into the access vessel, through the introducer sheath.

[0043] Figures 16 to 20 illustrate the steps of the method of insertion of the vascular device 10 in an anterograde manner intravascularly into the popliteal vein "P". The application catheter or sheath 200 is inserted onto a conventional guidewire (not shown) so that the distal tip 201 of the catheter shaft extends beyond, that is, downstream of the valve valves L which extend annularly from the vessel wall "V" as shown in Figure 16. As can be seen, since there is a gap "a" between the valve valves "L", the valve cannot function properly because the valves cannot be closed properly to prevent backflow. In addition, due to the malfunction of the valve, the vessel wall dilates as shown, to the extent that the weight and pressure of the blood backflow pushes the vessel wall outward.

[0044] Once the position of the sheath 200 is confirmed by venography, intravascular ultrasound, or other means, the sheath 205 is removed with respect to the tip 201 of the catheter in the direction of the arrow of Figure 17, leaving the discovered the vascular device 10. When sheath 205 has been completely removed to expose device 10, the device is heated by body temperature and makes a transition to its austenitic phase and the first expanded configuration memorized in Figure 18.

[0045] Next, a balloon member 240 in the axis 209 of the catheter, which is positioned within the device 10, is swollen by the introduction of fluid through the inflation lumen 206 (Figure 12) to further expand the device 10 to a second expanded configuration shown in Figure 19. That is, the device expands to a diameter greater than the diameter of its memorized configuration of Figure 18, so that the vessel coupling members 28, 40 and 42 will be coupled to the wall of the vessel "V", penetrating the leaflets and sharp tips on the wall of the glass to hold it and secure it firmly. This consolidation limits both radial and axial movement of the vessel to improve retention by the device

10.

[0046] After retention of the vessel wall as in Figure 19, the balloon deflates (and catheter 200 is removed), resulting in the device 10 contracting from the second expanded configuration to its memorized configuration . Preferably, the device 10 will return substantially to the same diameter as the first expanded (memorized) configuration. Contracted, the device 10, due to the coupling of the coupling members to vessels with the inner wall of the vessel, pulls the wall of the vessel radially inwardly, whereby it is pulled radially into the leaflets to the position of the Figure 20 to close the separation "a". As can be seen, the vessel wall no longer dilates and the valve leaflets are sufficiently close, so that their tips come into contact to block the backflow and therefore their function is restored. The device 10 remains inside the vessel, maintaining the approach of the vessel wall to maintain the proper functioning of the leaflets.

[0047] The changing diameters of the vascular device 10 can also be seen by reference to the cross-sectional views of Figure 21A-21C. For reasons of clarity the application device has been removed. More specifically, Figure 21A corresponds to the initial position of the vascular device 10 in Figure 18, wherein the device 10 has been applied to the target vessel, and has expanded to the first expanded (memorized) configuration, but the members of Coupling to vessels have not penetrated the vessel wall. It should be appreciated that, in this configuration, the vessel coupling members may or may not be in contact with the vessel wall, although, in any case, they do not fully penetrate or secure the vessel to the same extent as in the second position. As shown, by way of example, the unhealthy dilated vessel may have an internal diameter D1 of approximately 14 mm. For reasons of clarity, the ball is not shown in Figure 21A.

[0048] Figure 21B corresponds to the position of the vascular device in Figure 19, wherein the balloon has swollen to radially expand the device 10 to a second expanded position in order to allow the vessel coupling members to penetrate in and retain (secure) the vessel wall. In this configuration, the vessel wall is further expanded to a diameter D2 of approximately 16 mm, to the extent that the device expands to a diameter of approximately 16 mm, the hooks extending an additional 2 mm so that the device It expands up to 20 mm.

[0049] Figure 21C corresponds to the position of the vascular device 10 in Figure 20, wherein the balloon has deflated and the device has contracted to move the vessel wall radially inward. The internal diameter of the vessel wall will preferably be approximately 12 mm to close the gap between the leaflets. The diameter of the vascular device 10 preferably returns to the same diameter as in Figure 21A, for example, approximately 12 mm. As can be seen, the device 10 rests on the wall of the vessel V.

[0050] Figures 22 to 26 illustrate the retrograde insertion of the vascular device 10. In this approach, the application catheter, for example, catheter 210, is inserted in a direction against blood flow, so that the tip 211 extends beyond the valve valves "L" in the popliteal vein "P", and the catheter 210 is positioned so that the device 10 will be deployed upstream of the leaflets. On the other hand, the deployment of the device 10 is the same as in Figures 16 to 20. That is, the sheath 215 of the application device 210 is retracted in the direction of the arrow of Figure 23, to expose the device. 10. Complete withdrawal and withdrawal of the sheath 215 to expose the device to the highest body temperature allows it to expand to its (first) memorized (expanded) configuration of Figure 24. The subsequent expansion of the balloon 250 (Figure 25) causes the vessel coupling members 42, 28, 40 to penetrate and retain the vessel wall, so that, upon deflation of the balloon, the device 10 returns to the configuration memorized from Figure 26 by pulling the vessel wall inwards and bringing the valve valves “L” closer together until the apposition, so that the tips can come into contact. The changing diameters would also correspond to the cross-sections described above in Figure 21A to 21C.

[0051] As can be seen, the device 10 and the device 100 are each symmetrical, so that in the present case the "proximal" and "distal" portions are identified for convenience.

[0052] Figures 27 to 29 illustrate an alternative embodiment of the vascular device generally designated with reference numeral 300. This shape memory device 300 is illustrated and described in provisional patent application No. 60 / 214,120, filed on June 6, 2000. The device 300 is placed inside the vessel V, for example, the popliteal vein to approximate the leaflets "L" which, as shown in Figure 27, are not functioning properly since the tips L1 are separated. In its first expanded configuration corresponding to its memorized form of Figure 27, the hooks 314 have not penetrated the vessel wall. The device 300 is formed by struts 302, as described in detail in the application '120. The hooks 314, adhered to the struts 302 in the region 304 have a crescent shape and have pointed ends 306 with portions 308 with beards.

[0053] In the expanded configuration of Figure 28, the balloon 322 on the axis 324 of the application device has expanded the device 300 so that the hooks 314 penetrate and firmly engage the wall of the vessel "V". Next, the balloon would deflate and the device 300 would return to its first expanded configuration, moving the vessel walls radially inward and placing the valve valves in apposition, in the same manner as described above with respect to the vascular device 10.

[0054] Figures 30 and 31 illustrate an alternative method of vascular device placement. In this method, the vascular device 10 (or vascular device 100) is placed downstream (with respect to the direction of blood flow) of the valve leaflets. Downstream (with respect to the direction of blood flow) of the valve leaflets. Application catheter 210 'is inserted in the same antegrade manner as described above with respect to Figure 16, except that it is advanced sufficiently beyond the valve valves L to allow application of the device 10 downstream. Once it has been positioned as shown in Figure 31, the sheath 215 'is removed in the direction of the arrow, allowing the device 10 to expand to its memorized configuration. Next, the vascular device 10 would be further expanded by means of a balloon and then its contraction would be enabled until its memorized configuration in the same manner as in Figures 18 to 20, the only difference being that the device 10 would grip the vessel wall downstream of the valvular leaflets to pull the vessel wall radially inward in order to place the leaflets in apposition.

[0055] It should be appreciated that device 10 or device 100 could also be applied in a retrograde manner, as shown in Figures 13 to 15, to position the device downstream of the leaflets L.

[0056] Figures 32 to 34 illustrate an alternative system and application method for vascular device 10 (or device 100, which can be applied in the same way). In this method, the exposure of the vascular device to body temperature and the expansion of the balloon occur substantially simultaneously. To facilitate placement, a restraint system is provided to connect the vascular device to the balloon.

[0057] More specifically, the balloon 250 'has a pair of sutures 252 fixed thereto in a proximal and distal portion, which wrap the vascular device 10 forming a suture loop to connect the balloon and the device. Although two sutures are shown, it is contemplated that one suture or more than two sutures may be used to connect the balloon 250 'to the vascular device 10. Additionally, other fastening systems, such as perforated strips, may be used.

[0058] In the position of Figure 32, the sutures (of which only one is shown, the other suture still being inside the sheath 215 ') loosely envelop the device. When the pod 215 'retracts in the direction of the arrow, the balloon swells. Thus, when the sheath 215 'is completely removed, the device expands to the position of Figure 33, without the intermediate stage required in the methods described above, that is, without the stage of Figure 24, which first instead allows the device to expand to the memorized configuration. When the balloon expands, the pressure against the sutures 252 breaks the suture loops, thus freeing them from the vascular device 10. Thus, when the balloon 250 'is deflated and removed with the catheter 210' of application with respect to the body, the sutures 252 are also removed. Upon deflation, the vascular device 10 returns to its memorized configuration to pull the vessel wall radially inward according to the manner described above, in order to adopt a position like that of Figure 26.

[0059] Note that it is also contemplated that the balloon 250 'may first swell inside the sheath, followed by removal of the sheath to expose the vascular device 10 at body temperature.

[0060] Additionally, the clamping system can also be used with the sequential deployment method of Figures 16 to 20 and Figures 22 to 26. The clamping system, for example, sutures, would help avoid axial movement and they would help center the balloon with respect to the vascular device 10.

[0061] Although the above description contains many details, such details should not be considered as limitations on the scope of the exposure, but merely as exemplifications of preferred embodiments thereof. In addition, instead of moving the sheath to expose the vascular device, the catheter can be advanced with respect to the sheath or both the catheter and the sheath can move relative to each other in opposite directions. Those skilled in the art will devise many other possible variations that are within the scope of the exposure, as defined by the claims appended herein.