MXPA99007082A - Disposal of vascu filter - Google Patents

Abstract

A removable vascular filter arrangement for blocking micro-embolisms and macro-emboli while allowing continued blood perfusion comprises a filter membrane positioned on a wire guide, in which the free end of the membrane sits tightly against the wire guide when the filter membrane is in a folded state and in which the filter has an element for deploying the filter membrane to assume a substantially normal position to the longitudinal axis of the wire guide, the filter membrane is composed of a material of fine mesh having a pore size capable of blocking emboli while allowing continued blood flow, a preferred embodiment of which comprises holes formed by lasers, spaced regularly

Description

DISPOSAL OF VASCULAR FILTER FIELD OF THE INVENTION The present invention relates to a treatment of vascular diseases by surgery or percutaneous angioplasty and stenting. In particular, the invention relates to an arrangement that reduces macroembolization and micro-embolization during the treatment of vascular stenosis.

BACKGROUND OF THE INVENTION A variety of surgical and non-surgical angioplasty interventions have been developed to remove obstructions of blood vessels. Balloon angioplasty uses a catheter with a balloon at the tip that can be inserted into a stenosed region of the blood vessel. By inflating the ball, the stenosed region is dilated. The surgery involves removing the plaque from the artery or linking a graft to the artery so as to "bypass" the obstructive plaque. Other techniques, such as atherectomy, have also been proposed. In atherectomy, a rotating blade is used to scratch plaques of an arterial wall. A common problem for all these techniques is that accidental detachment of portions of the plaque or thrombus results in embolisms that may be lodged elsewhere in the vascular system. Supposed such emboli are extremely dangerous for the patient, frequently causing severe deterioration of the distal circulatory cause. Depending on the vessel being treated, this can result in a stroke or myocardial infarction or limb ischemia. Vascular filters or embolic traps for implantation into the vena cava of a patient are well known, and are illustrated, for example, in U.S. Patent Nos. 4,727,873 and 4,688,553. In addition, there is a large amount of medical literature that describes various designs of vascular filters and that report the results of clinical and experienced use thereof. See, for example, the article by Eichelter & Schenk entitled "Prophylaxis of Pulmonary Embolism," in the Archives of Surgery, Volume 97, August 1968, pages 348 and seeds. See, also, the article by Greenfield et al, entitled "A New Intracaval Filter that Allows Continuous Flow and Embolism Resolution", Surgery, Volume 73, N | 4, pages 599-606 (1973). Vascular filters are used, often during post-surgical periods, when there is a perceived risk of a patient having a pulmonary embolism resulting from boxes generated at the surgical site or similar. As a typical use of vascular filters, the filter is mounted in the vena cava to trap large embolisms that pass from the surgical site to the lungs.

The vascular filters according to the prior art are usually permanently implanted in the patient's venous system, so that even after the need to have the filter is finished, the filter remains in place throughout the patient's life, without surgical extraction. U.S. Patent No. 3,952,747 discloses a stainless steel filtering device that is permanently transvenously implanted within the inferior vena cava. The filtering device is intended to treat recurrent pulmonary emboli. U.S. Patent No. 4,873,978 discloses a catheter device comprising a catheter body having a filter mounted at the distal end. The filter is movable between an open configuration where it is substantially arranged through the blood vessel to trap the passer emboli, and a closed configuration where it retains the embolisms trapped during catheter removal. A mechanism operable at the proximal end of the catheter body allows selective opening and closing of the filter. Typically, the filter is a foldable cone having an apex linked to a wire that passes from the distal end to the proximal end of the catheter body. It is often considered that permanent implantation is medically inconvenient, but this is done because the vascular filters are implanted in patients primarily in response to potentially life threatening situations. Therefore, the advantages of permanent implantations of a vascular filter are often accepted. In order to avoid permanent implantation, it would be very convenient to provide an apparatus and method to prevent embolization associated with conventional surgical procedures and agioplasty. In particular, it would be convenient to provide a device that could be located within the vascular system to collect and recover portions of plaque and thrombus that have been dislodged during the surgical or angioplasty procedure.

OBJECTIVES OF THE INVENTION An object of the present invention is to provide a vascular filter arrangement for reducing macro embolization and micro embolization. Another object of the present invention is to provide a vascular filter arrangement that is easily removable from the vascular system, or from another location, of a patient when the filter is no longer needed. Another object of the present invention is to provide a vascular filter arrangement having a configuration that does not require hooks that penetrate and grip the walls of the blood vessel, so that the implant results in less injury to the blood vessel. Yet another objective of the present invention is to provide a very low profile vascular filter arrangement that is part of a guide wire and can be used for small vessels.

These and other objects of the invention will be further evidenced in the following description.

SUMMARY OF THE INVENTION The present invention relates, in general, to a vascular filter arrangement useful in the surgical or interventional treatment of vascular diseases, in particular, a novel percutaneous angioplasty and a useful disposition for stenting, for example, in the treatment of stenosis. of the carotid. Macro-embolization and micro-embolization occurs during percutaneous interventions such as angioplasty, which increase the risk of minor or major strokes. The provision of the present invention to reduce macro-embolization and micro-embolization is very useful in helping to prevent the risk of strokes. However, this provision would also be useful in any surgery or surgical intervention where embolization constitutes a risk. The vascular filter arrangement of the present invention will decrease embolism while allowing the brain, or other distal tissue, to perfuse. The filters are incorporated into a wire guide that is used for the entire intervention from the crossing of an injury to the installation of a stent. In one embodiment the filter consists of a thin membrane linked to the wire guide and supported by thin metallic spines. The bonding of the filter membrane to the wire guide allows the expansion of the filter membrane with a firm fit within the artery. The binding also allows the filter membrane to be folded at the end of the operation so that it is tightly disposed against the wire guide and can be removed through the guide catheter. In another embodiment, the filter membrane supports or is linked with a structure similar to a basket, at least one end of which is linked to the wire guide. The filter membrane has a pore size such that blood flow is not impeded when the filter membrane is expanded, but micro embolisms and macro emboli are blocked. The expansion of the filter membrane is aided by the forward flow of blood against the filter. The filter design results in a very low profile so that the initial crossing of the lesion is minimally traumatic. Likewise, the small diameter and small profile facilitate the use of the device in small or larger arteries with minimal suction or without obstruction of blood flow.

BRIEF DESCRIPTION OF THE DRAWINGS The objects and advantages indicated above and other objects and advantages of the invention will be apparent from the following detailed description, with reference to the accompanying drawings, in which similar reference characters refer to like parts in all the figures and in which: Figure 1 is a side view, partly in cross section, of the distal end of a wire guide of an embodiment of the invention with the filter membrane in a folded position; Figure 2 is a side view, partly in cross section, of the distal end of a wire guide according to Figure 1 with the filter membrane in an expanded installed position; Figure 3 is a proximal end view of the filter membrane shown in Figure 2; Figure 4 is a side view, partly in cross section of another embodiment of the invention; Figure 5A is a side view, partly in cross section of yet another embodiment of the invention; Figure 5B is a side view, partly in cross-section of the embodiment of the invention shown in Figure 5A with the filter membrane in an expanded installed position; Figure 6 is a partly cross-sectional view of a control handle for the invention; Figure 7 is a partly cross-sectional view of another embodiment of the invention; Figure 8 is a partial cross-sectional view of an embodiment of the invention in which the filter membrane has bent supports; Figure 9 is a partial cross-sectional view of yet another embodiment of the invention in which the filter membrane has a spiral wire; Figure 10 is a partly cross-sectional top view of the embodiment of the invention shown in Figure 9; Figure 11 is a partial cross-sectional view of another embodiment of the invention having inflatable support spines; Figures 12 and 13 represent partial cross-sectional views of another embodiment of the invention in folded position and in installed position, respectively; Figure 14 is a side view, partly in cross section of an embodiment of the invention with the filter membrane in an open position; Fig. 15 is a partly cross-sectional side view of the embodiment of the invention of Fig. 14 with the sheath closed; Figure 16 is a schematic representation of a portion of a filter membrane useful according to the invention; Figure 17 is a side view of a central thin rod useful according to the invention; Figure 18 is a cross-sectional view through line 18-18 of a portion of a central thin rod of Figure 17; Figure 19 is a side view, in cross section, of an alternative channel structure for the embodiment of Figure 14; Figure 20 is a side view, partly in cross section of another embodiment of the invention; Figure 21 is a side view, partly in cross section of another embodiment of the present invention; Figure 22 is a schematic, partially cross-sectional view of another embodiment of the invention where the distal section of the filter basket is inverted; and Figure 23 is a schematic, partially cross-sectional view of the embodiment shown in Figure 22 where the filter basket is folded.

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vascular filter arrangement for use in percutaneous angioplasty and stenting and serves to prevent emboli during endovascular interventions. Likewise, the filter arrangement of the invention serves for distal perfusion while preventing embolization. The arrangement comprises a thin perforated filter membrane, which is capable of blocking embolisms and which is linked to the distal end of a wire guide. In one embodiment the arrangement uses thin fibers which are displaceable and which are bondable to or encapsulated by the filter membrane for installation and / or folding of the filter membrane. The invention also contemplates the use of metal spines or inflabible spines attached to the filter membrane to deploy the filter membrane. The fibers or spines may also be linked to a movable central portion which is slidable within the wire guide and which is used to unfold and fold the filter membrane. The filter membrane is deployed in a manner similar to an umbrella with the unbonded edge of the membrane moving upward, i.e., distally, and outwardly until it is in firm contact with an arterial wall. When the filter membrane is displaced, it encompasses the cross-sectional area of the vessel lumen that is being treated by stenosis such as carotid stenosis, or another condition that is likely to produce embolism. In another preferred embodiment of the invention, a thin, flexible, perforated membrane is supported by four or more supports forming a basket disposed distally. At least one end of the basket is linked to the wire guide, and the other end, slidable can not be moved to be that the membrane open or close. The invention will be better appreciated with reference to the drawings. Figure 1 illustrates a side cross-sectional view of a distal end of a wire guide 10 with a filter membrane 30 attached thereto. Figure 1 shows the wire guide 10 with a soft taper tip 15 conformable at its distal end which provides flexibility and maneuverability for the wire guide 10. The filter membrane in Figure 1 is in a folded position. The filter membrane 20 has a portion 24 that is displaceably linked to the wire guide 10, and the filter membrane 20 is disposed adjacent the wire guide 10 proximally to the fixed portion 24 when the filter membrane 20 is in the vicinity of the filter membrane 20. folded state. A centrally displaceable wire 40 passes through a central lumen 1 1 of the wire guide 10 and is preferably disposed distally at a short distance further from the fixed potion 24 of the filter membrane 20. Each of the wires or fibers 30 of deployment is firmly attached at one end 27 to the central wire 40 displaceable distal of the fixed portion 21 of the filter membrane 20. The unfolding fibers 30 are linked at their other ends to the filter membrane 20 at bonding points 22 Each of the folding fibers 30 is firmly attached at one end 12 to the movable central wire guide portion 40 which is internal to the filter membrane 20 when it is in a folded state. Each of the folding fibers 35 is linked at its other end 13 to the filter membrane 20 at the bonding points 22. Accordingly, the folding fibers 35 are disposed inside the filter membrane 20 when the filter membrane 20 is in the folded state. The filter membrane 20 is unfolded when the operator pulls the central wire 40 displaceable proximally through the interior of the wire guide 10. Prior to retraction of the movable wire guide 40, the deployable fibers 30 are sufficiently relaxed so that they do not create any tension in the points 22 of attachment to the filter membrane. When the movable wire guide 40 is retracted, tension is created in the deployable fibers 30. Preferably there will be between 2 and 6 deployable fibers 30 evenly spaced and foldable fibers 35, with 3 or 4 being the most preferred amount. The deployable fibers 30 and the collapsible fibers 35 can be made of any flexible material that is medically acceptable, including stainless steel, nitinol, or other metal or metallic alloy of a non-metallic substance such as graphite or a suitable polymer. In addition, the wire guide 10 and the displaceable wire 40 can be made with similar materials, as will be appreciated by those skilled in the art. Typically, the wire guide 10 could have an outer diameter comprised between about 0.014 mm to about 0.035 mm, a wall thickness comprised between 0.002 mm and about 0.010 mm, and a length comprised between about 25 cm and about 300 cm. Also, the displaceable central wire 40 could have a diameter between about 0.03 mm and about 0.010 mm and a length between about 30 cm and about 350 cm. Figure 2 illustrates the filter device of the invention in an unfolded position inside an arterial wall 60. The displaceable central wire 40 is in a retracted state, ie, pulled proximally through the interior of the wire guide 10. Tension is created when the fibers 30 are deployed, and the filter membrane 20 is arranged in an unfolded position where the outer edge 14 of the filter membrane 20 contacts the arterial wall 60. In this deployed position, the collapsible fibers 35 are a relaxed state and are arranged from the attachment points 35 of the filter membrane to fixed fixing points 28 on the displaceable central wire 40. In Figure 2 the blood flow is towards the distal end of the wire guide 10. As such, the force of the blood flow pushes on the expanded filter membrane 20 and helps maintain the filter membrane in the unfolded position. To extract the wire guide 10 and the filter device, the filter membrane 20 is made to fold so that it sits tightly against the wire guide 10. This is done by passing the central wire 40 displaceable distally through the guide wire. wire 10, thereby relaxing the deployable fibers 30 and creating tension in the collapsible fibers 35. Tension in the collapsible fibers 35 causes the filter membrane 30 to fold, allowing it to fit snugly against the wire guide in the recess 16 as illustrated in Figure 1. Figure 3 illustrates the filter device of the invention from a distal end view in Figure 2 with the filter membrane 20 deployed. The wire guide 10 is located centrally, and the structural wires 50 are shown arranged from the wire guide 10 to the outer edge 14 of the filter membrane 20. These wires 50 will provide structural integrity and rigidity to the filter membrane 20. Figure 3 illustrates four structural wires 50 evenly spaced, but there may be more or less structural wires 50. Preferably there are between two structural wires 50, which may be spaced regularly or irregularly. The wires 50 may preferably be made of stainless steel or another metal or medically acceptable alloy. The filter membrane 20 of the invention is preferably a mesh such as the one illustrated in Figure 3. The mesh must have pores of sufficient size to block and capture any micro embolism and macro embolism that may flow downstream from the site where the Stenosis is being treated, large enough so that blood flow is not obstructed. The mesh used in the filter device of the invention may have a pore size between about 20 and about 300 microns, preferably between about 50 microns and about 150 microns. Also, the size of the filter membrane 20, ie the distance from the wire guide 10 to the free ends 22 is such as to allow a firm fit between the filter membrane 20 and the arterial wall 60. The diameter of the filter membrane 20 will be directly related to the artery being treated, with typical diameters ranging from about 2 mm to about 40 mm, more preferably between about 2 mm and about 20 mm. The membrane may be composed of fabric or non-fabric meshes, such as those used in known hemodialysis filters or filters of cardiac-pulmonary bypass machines. Suitable materials include psychologically acceptable polymers or metals or alloys. In alternative embodiments of the invention, which are shown in Figures 4, 5A and 5B, the filter membrane 20 will be suspended between two to eight, preferably between four to eight, thin metal wires 51 which serve as spines of supports for the membrane of filter 20. The wires 51 can be made of stainless steel or another metal alloy, nitinol, or other shape memory material. The wires 51 will be constructed so that they adopt a 90 ° angle with the wire guide 10 when in an unrestricted state. This will result in an expansion of the filter membrane 20 to a position normal to the wire guide 10. A set of thin fibers 17 are linked at bonding points 18 to the outer edge 14 of the filter membrane and are used to make folding the filter membrane 20. Figure 4 shows an embodiment of the present invention in which the metal wires 51 are allowed to return to their unrestricted state at an angle of 90 ° by the use of a displaceable central wire 40 which is arranged to Through the wire guide 10. Prior to the retraction of the displaceable central wire 40, the fibers 17 are sufficiently tensioned so as to restrict the wires 51. When the retraction of the displaceable central wire 40 occurs., the tension of the fibers 17 is released and it allows the wires 50 to return to their relaxed form, which will result in the expansion of the filter membrane 20 to a position normal to the wire guide 10. Figures 5A and 5B show an embodiment of the invention in which the wires 51 are constrained by the fibers 17 which pass through the wire guide 10 and which are controlled at a remote location. In Figure 5A, there is sufficient tension in the fibers 17 to maintain the wires 51 in a restricted position. In Figure 5B, the tension in the fibers 17 has been loosened so that the wires 51 are allowed to return to their relaxed form, which will result in the expansion of the filter membrane 20 to a position normal to the guide. wire 10. Figure 6 illustrates a control handle especially suitable for the embodiment of the invention shown in Figures 5A and 5B. The proximal end 32 of the wire guide 10 is rotatably linked to the handle 33, so that the rotation of the handle 33 causes the handle 33 to move distally or proximally relative to the proximal end 32 of the wire guide. For example, the handle 33 may have threads 34 threaded into threads 35 at the proximal end 32 of the wire guide. The fibers 17 linked to the filter membrane 20 are fixed on a base 36 of the handle 33. Then, as the magnet 33 is rotated, the fibers 17 move distally or proximally to open or close the filter membrane 20. As the handle 33 is rotated without clockwise in the direction of the arrow A and the fibers 17 are allowed to move distally in the direction of the arrow C, the tension in the fibers 17 of the filter membrane decreases and the wires 51 are allowed to assume their natural 90 ° angle with respect to the wire guide, resulting in the opening of the filter membrane 20. Similarly, when the magnet 33 is rotated counterclockwise in the direction of the arrow B and the fibers 17 are pulled proximally in the direction of the arrow D, the tension in the filter fibers 17 increases, causing the filter membrane 20 to press tightly against the wire guide 10. Of course, the dir The turning force of the magnet 33 as described above can be inverted, provided that the thread threads 34, 35 are correctly formed to allow proper displacement of the magnet 33 relative to the proximal end 32 of the wire guide. In yet another embodiment of the invention shown in Figure 11, the filter membrane 20 can be supported by inflatable spines that support the filter membrane 20. The spines 135 that support the filter membrane 20 are between two six hollow plastic tubes that are inflatable using, for example, a standard or endoinflation balloon angioplasty inflation device in connection to the fluid passage through the channel 137 with the spines 135. The inflating of the spines 135 makes the same they become rigid and take off the filter membrane 20. The underside of the filter membrane is linked to very thin fibers 17 which are linked to the displaceable wire 40 inside the hollow wire guide 10. The filter membrane 20 deployed deflates the spines 135 and extracting the central wire 40 displaceable in the direction of the arrow E until the membrane 20 fits snugly against the wire guide 10. As shown in figure 7, a catheter-based configuration is also possible. In this design, the wire guide is not part of the filter catheter; The wire guide and the filter catheter are two separate components. The filter catheter has an entry hole for the wire guide below the bonding of the filter membrane and the wire guide exits the end of the filter catheter. The filter catheter could be designed to accommodate a variety of sizes of wire guides, most commonly 0.35 mm wire guides. Advantages of this design is that a variety of wire guides could be used; the lesion could be crossed with the wire guide before crossing with the filter catheter; it could be removed from the artery without removing the wire guide; and the filter catheter could be made smaller. In the embodiment of the invention shown in Figure 7 a catheter comprises a lumen 103 arranged longitudinally, having an annular recess 105 adjacent to the distal end of the catheter 101. Positioned within the recess 105 is a filter 107 comprised of structural wires 109 a filter membrane 1 11. The distal end of each of the wires 109 is attached to it. point 1 13 in the recess 105. The fibers 1 17 are disposed from the proximal ends 1 19 of the wires 109 proximally to a control element as described in Figure 6. The catheter 101 contains the mouth 125 of the wire guide Located proximal to the recess 105. It is proposed that in use the distal portion 128 of the wire guide 127 is screwed inwardly of the distal end 129 of the catheter 121 and outwardly through the outlet 125. Alternatively, although not shown, a catheter 101 could comprise a longitudinally disposed lumen and a shorter tracking lumen running from the distal end 129 to a point proximal to the recess 105.

Then the distal end of the wire guide 127 would thread into the distal opening of the tracking lumen and outwardly through the proximal end of the tracking lumen. The place of the straight wires could be used spiral or curved structural wires to detach the filter membrane. Figure 8 illustrates the use in four curved wires 120. The angulation of the bonding point of the filter of the wires 120 in relation to their connection to the wire guide has the effect of wrapping the filter cloth around the wire guide in the undeployed state. This leads to a lower profile for the undeployed filter. Figures 9 and 10 illustrate the use of a single structural wire in the spiral 130 that is linked to the filter 107. As the tension in the fiber 131 is released, the wire 130 unrolls and unfolds the filter 107 in a conical configuration. This configuration has the simplicity of using a single wire and when the tension in the fiber 131 is increased it allows the filter 107 to be wrapped very tightly around the wire guide, resulting in the filter 107 having a low profile in its state not deployed. Another modification shown in Figures 12 and 13 comprises a retractable sheath 140 at the distal end of the wire guide 142 covering the filter membrane 144 in the folded state. The sheath 144, the distal portion in which it is attached to the tip 146 of the wire guide is fixed to the distal end of the displaceable central wire 148, would prevent an edge 150 of the filter membrane 144 from being trapped in an artery or catheter of guidance when it is being extracted from a patient. More specifically, when the wire guide 142 with the tapered tip 146 is inserted percutaneously into a patient, the sheath 140 covers the folded filter membrane 144. After fluoroscopy determines that the filter membrane is in the correct position, the movable center wire 140 is pushed distally to cause the sheath 140 to "release" the filter membrane 144, which has spines 152, to make the membrane of filter 144 deploy, as shown in Figure 13. Figure 14 illustrates a side view, in cross-section, of a distal end of a wire guide 160 with a filter membrane 170 linked to it. Figure 14 shows the wire guide 160 with a soft "flexible" tip 162 conformable at its distal end, which provides flexibility and maneuverability for the wire guide 160. The filter membrane in Figure 14 is in an open position. The wire guide 160 comprises a central wire 164, which is disposed inwardly of the flexible tip 162, and a sheath 166. The filter membrane 170 is supported by a basket 169 comprising two or more wires 168 of the filter basket, they have distal ends 172 and proximal ends 174. The distal ends 172 of the wires of the basket 168 are fixedly linked by a distal radiopaque marker or a crimping band 176 to the central wire 164, and the proximal ends 174 of the wires 168 of the basket are linked to the radiopaque marker or proximal crimping band 178, which is slidable on the central wire 164, optionally with a polymeric sleeve, such as polyimide, or metallic between the central wire 164 and the proximal ends 174. Optionally, and preferably, the proximal marker 178 is fixedly attached to central wire 164, and distal marker 176, with a polymeric or metallic sleeve, is slidable on the central wire 164. A sheath component 180 is linked to the distal end of the sheath 166, and the sheath component 180 has a lumen 182 with a diameter and length sufficient to receive or slide over the proximal marker 178. The sheath 166 and the pod component 180 may be separate pieces joined together or an integral continuous structure. The pod 166 and the pod component 180 are, each made with a low friction polymeric material, preferably polytetrafluoroethylene, polyethylene, nylon, or polyurethane. The filter membrane 170 may comprise a number of different permeable metallic or non-metallic membranes having sufficient porosity to facilitate blood flow but having openings small enough to capture emboli. The filter membrane 170 should at least be fixed at its distal portion 184 to the central wire 164 and / or the distal ends 172 of the basket wire and, optionally, to the wires 168 of the basket. The this of the filter membranes 170 may be linked or, preferably, linked to the wires 168 of the basket, such as by means of a suitable adhesive. Preferably the wires 168 of the basket are encapsulated in the membranes 170. The basket 169 may be cylindrical in general in its middle part with tapered tapered proximal and distal portions. Alternatively, the basket 169 may be a little spherical, optionally with a flat cylindrical middle portion. Preferably the basket 169 has a length comprised between about 5 mm and about 40 mm and a diameter between about 2 mm and 30 mm, or between about 2 mm and about 20 mm, at its widest portion. The proximal end of the sheath 180 is linked to the control handle or torque-applying device 186 of the wire guide. The control magnum 186 has an opening 188 for the central wire 164, so that the sheath 180 can slide slidably over the central wire 164. For example, when the sheath 180 is displaced distally towards the wires 168 of the basket, the membrane filter 170 unfolds. There may also be cases where the sheath 180 will be removed proximally so that other catheters or cardiovascular implements may be introduced over the central wire 164. The control handle 186, which functions as a torque-applying device, also functions primarily for locking the sheath 180 to the guide wire 164 during insertion. There are a number of known, commercially available, wire guide torque adjusting devices that can be modified to function as control magnum 186. The modification influences, without limitation, providing a somewhat larger central lumen. In Figure 15 the sheath 166 and the pod component 180 are shown advanced distally so that the wires 168 of the basket and the filter component 170 are folded against the central wire 164. The distal ends 192 of the sheath component 180 can be optionally a little tapered to provide a better profile for insertion. In a preferred embodiment of the invention, as shown in Figure 16, the filter membrane 170 comprises a polymeric material such as polyurethane or a silicone elastomer having holes 190 drilled by laser. Such holes 190, a configuration of which is shown in Figure 16, are preferably only in the conical portion of the filter membrane 170. The holes 190 can have a diameter between about 50 microns and 300 microns. The vertical separation between rows of holes 190 may be between 1, 2 and 1, 4 times the diameter of the holes and the diameter between centers of holes may be between approximately 1, 4 and 1, 6 times the diameter of the holes or in a preferred embodiment the vertical and horizontal spacing of the holes is such that the center spacing of the holes is between about 1, 2 and 2.0 times the diameter of the holes. Preferably, the open area of the holes represents between about 10 and 50%, more preferably between about 10% and 40%, of the filter surface. The wires 168 of the basket can be of a suitable, psychologically acceptable metal. Stainless steel or nitinol is preferred, although titanium or other metal alloys can be used. In FIG. 17, the central thin rod 164 is better shown, in which the proximal portion 200 and the middle portion 202 are of substantially uniform diameter and the distal portion 204 is tapered to an end point 206. Actually, the distal portion 204 it could taper uniformly or, more preferably non-uniformly, as shown in Figure 17. Typically, the thin rod 164 has a length comprised between about 250 cm and 300 cm, with an initial diameter between about 0.23 mm and 0, 96 mm, preferably between approximately 0.35 mm and 0.46 mm. The distal section 204 has a fixed length of between approximately 8 cm and 10 cm, with a tapered diameter comprised between approximately 0.025 mm and 0.127 mm. The central thin rod 164 may optionally have a thin polymeric coating 207 to reduce friction.

Preferably the end point 206 is a solid, short and wide cylinder, as shown in Figures 17 and 18. The flexible tip 162 preferably comprises a radiopaque helical spring 210 which is fixedly attached, for example, by welding, brass welding, or soft solder, and the end point 206 and, optionally, to the bonding point 208. Optionally, the helical spring may have a polymeric or sliding liner 212. Figure 19 represents an alternative design where the wires 220 of the basket are substantially helical in shape. The filter component 222 covers or encompasses the distal portion of the wires 220 of the basket, and the proximal portion and the distal portion of the wires 220 of the basket are fixed by means of a radiopaque marker or proximal crimping band 224 and a radiopaque marker. or distal crimped band 226, respectively. The markers 224 and 226 are fixed or slidable in the central wire 228 as described above. Preferably there are between 4 and 8 basket wires 220, each with a rotation between about 45 ° and 360 °. Figures 20 and 21 show further embodiments of the invention. The schematic representation of Figure 20 illustrates a filter membrane 280 supported by holding wires 288. The distal ends 284 of the holding wires 282 are linked to the distal portion of a tubular component 286. A displaceable central wire 290 passes through from a lumen 292 in the tubular component 286 to a distal flexible section 294, where a helical spring coil 296 encircles the distal portion 298 of the central wire 290 and is linked to the end point 300. There is a bonding point 302 for welding or soldering in the proximal portion of the elastic coil 296 where the distal portion 304 of the pod component 306 is also fixed to the central wire 290. The lumen 308 of the sheath component 310 is sufficiently large so that as the central wire 290 is pulled proximally or the tubular component 286 is advanced distally, the distal ends 284 of the wires 288 move within lumen 308 and cause the filter membrane 280 to fold. The displaceable center wire 250 of the structure shown in Figure 21 comprises a flexible tip 252 where a helical spring coil 254 spans the distal portion 256 of the central wire 250. A basket wire structure component of two or more basket wires 258 supports a filter membrane 260 in the distal portion 268 of the basket structure. The distal ends 164 of the wires 258 of the basket are encompassed by a radiopaque marker or a crimping band 266 that is linked to the central wire 250 and / or the elastic coil 254. The proximal ends 268 of the basket wires 258 are linked to the distal portion of a sheath 270 surrounding the central wire 250. The sheath 270 slides on the central wire 250, so that when the sheath 270 is pulled proximally into the central wire 250, the filter membrane 260 I folded . In Fig. 22 a basket 320 comprising between 4 and 8 support wires by a distal fixed guard ring 324 and a proximal slidable guard ring 326. The guard ring 326 is slidable on the central wire 328. The filter membrane 330 is linked to the basket 320 or disposed on the basket 320, the proximal section 332 of the membrane 290 being open for flow, represented by the arrows 334.

The distal portion 336 of the membrane 330 forms a conical shape 340 that is disposed proximally. The filter could be deployed, for example, by a sheath or a tube attached to the proximal slideable crimping band 336. This design is optimized for perfusion and collecting embolisms. For example, as more embolisms are collected, it tends to collect in external areas, without filter, leaving open pores for perfusion. The membrane 330 preferably has holes only in the distal section 336/340, whose holes are arranged as described above. It is considered that under normal, substantially laminar flow conditions, debris or embolisms 342 will tend to collect in annular recesses 344. To close and capture embolisms, as shown in FIG. 23, the slide protective ring 326 is displaced proximally to folding the basket 320 and the membrane 336. This can be effected, for example, with the sheath 350 or a fixed tubular component or other apparatus which is preferably slidable on the central wire.

The wires, membranes and other materials of this embodiment are consistent with those described above. The foregoing specific embodiments are illustrative of the practice of the invention. However, it should be understood that other resources known to those skilled in the art or disclosed herein may be employed without departing from the spirit of the invention or the scope of the appended claims.

Claims (53)

NOVELTY OF THE INVENTION CLAIMS

1. A removable vascular filter arrangement for blocking micro-embolisms and macro-emboli while allowing continued perfusion of blood, comprising: a wire guide having a distal end and a proximal end, a filter membrane having a distal portion and a free proximal end portion, wherein said distal portion is pivotally linked to the wire guide near said distal end of the wire guide and wherein the free proximal end portion is substantially parallel to the wire guide in its folded state; and unfolding elements for causing the filter membrane to assume a position substantially normal to the longitudinal axis of the wire guide.

2. The vascular filter arrangement according to the claim 1, in which the unfolding elements comprise a control mechanism at the proximal end of the wire guide operatively connected to the filter.

3. The vascular filter arrangement according to claim 1, wherein the filter membrane is composed of a porous mesh.

4. The vascular filter arrangement according to claim 3, wherein the pore size of the porous mesh is between about 20 microns and about 300 microns.

5. - The vascular filter arrangement according to the claim 1, in which the unfolding elements comprise movable central elements, the movable central element being slidably positioned inside the wire guide.

6.- The vascular filter arrangement according to the claim 5, in which the unfolding elements further comprise unfolded fibers each of which have a first end and a second end and said filter membrane further comprises an outer edge, and wherein each of said unfolded fibers is linked to a first end of the displaceable central element and is linked at a second end to the outer edge of the filter membrane.

7. The vascular filter arrangement according to claim 5, wherein the displaceable central element creates a tension in the unfolding fibers when sliding proximally in relation to the wire guide, and said tension causes the membrane filter expands outwards until the outer edge of the filter membrane is firmly in contact with the wall of the lumen.

8. The vascular filter arrangement according to claim 6 further comprising an element for collapsing the filter membrane from an unfolded state to a folded state.

9. The vascular filter arrangement according to claim 8, wherein the folding element further comprises folding wires, each of which has a first end and a second end, wherein each of said wires The folding element is connected at a first end to the displaceable central element and is also connected at a second end to the outer edge of the filter membrane.

10. The vascular filter arrangement according to claim 9, wherein the movable central element creates a tension in the folding wires when sliding proximally in relation to the wire guide, and said tension causes the membrane filter pleated tightly against the wire guide.

1 1. A removable vascular filter arrangement for blocking micro-embolisms and macro-emboli while allowing continued perfusion of blood, comprising: a wire guide having a distal portion and a proximal portion, in which there is a recess in the distal portion, the recess having a distal end and a proximal end, a filter membrane having an inner portion and a free end portion, wherein the inner portion is linked to the wire guide near the distal end of the recess of the wire guide and in which the free end portion is positioned in the recess when the filter membrane is in a folded state, and wherein the filter membrane in a non-stressed position assumes a substantially normal position to the longitudinal axis of the wire guide, and elements for folding the filter membrane from an unfolded state to a folded state.

12. The vascular filter arrangement according to claim 1, wherein the folding elements comprise folding wires each of which has a first end and a second end, wherein each of said wires Folding is linked at a first end to an outer edge of the filter membrane and the second end of each wire is disposed proximally through the wire guide to an actuator.

13. The vascular filter arrangement according to claim 12, wherein the actuator is a handle or shaft that can be used to release or fold the filter membrane.

14. The vascular filter arrangement according to claim 1, wherein the filter membrane comprises a set of inflatable spines, said spines being hollow plastic tubes.

15. The vascular filter arrangement according to claim 14, further comprising an inflator for inflating the spines, wherein said spines become rigid when inflated.

16. The vascular filter arrangement according to claim 15, wherein the inflator is an internal inflator.

17. A method of treating diseased bodily blood vessels in a patient, comprising the steps of: inserting a wire guide having a distal end and a proximal end with a filter in the folded state into a diseased blood vessel for positioning the distal filter to a diseased vessel segment, said filter including a filter membrane having a distal portion and a proximal free end portion, wherein the distal portion is pivotally linked to the wire guide near said distal end of the vessel. wire guide, deploy the filter, advance a therapeutic catheter distally over the wire guide to the diseased segment, treat the diseased segment with the therapeutic catheter, whereby any loosened fragment from the diseased segment is carried distally through the blood flow and is captured by the unfolded filter, remove the therapeutic catheter from the blood vessel, make the filter fold with any trapped fragment, and extract the wire guide from the blood vessel.

18. The method according to claim 17, wherein the therapeutic catheter has a stent disposed therein or comprises a dilatation balloon.

19. The method according to claim 17, wherein the therapeutic catheter comprises a surgical device.

20. A method of capturing embolisms after a surgical or interventional intervention in a patient, comprising the steps of: inserting a wire guide having a distal end and a proximal end with a filter in the folded state within a diseased blood vessel for positioning the distal filter to an interventional surgical site om, said filter including a filter membrane having a distal portion and a proximal free end portion, where the distal portion is pivotally linked to the wire guide near said distal end of the wire guide, unfold the filter, make the filter fold with any entrapped emboli, and remove the wire guide from the blood vessel.

21. - The method according to claim 20, comprising the additional steps after deploying the filter to advance a therapeutic catheter distally over the wire guide to a diseased segment, treating the diseased segment with the therapeutic catheter, whereby any A loose fragment from the diseased segment is carried distally by blood flow and is captured by the unfolded filter, and the therapeutic catheter is removed from the blood vessel.

22. A removable vascular filter arrangement for blocking micro-embolisms and macro-embolisms while allowing for continued perfusion of blood, comprising: a wire guide having a distal end and a proximal end, a filter membrane having a distal portion and a free proximal extreme portion, wherein said distal portion is pivotally linked to the wire guide near said distal end of the wire guide and wherein the free proximal end portion is substantially parallel to the guide wire of the wire guide. wire in its folded state; and a control handle at the distal end of the wire guide, the control handle being operably connected to the proximal free end portion of the filter membrane to cause the filter membrane to assume a substantially normal position to the longitudinal axis of the filter membrane. the wire guide.

23. A vascular filter arrangement comprising: a central wire having a proximal end and a distal end, a filter arranged concentrically around said central wire, said filter having a proximal end and a distal end, the distal end of the filter being filter connected to the central wire adjacent to its distal end and the proximal end of the filter being connected to the central wire, and a sheath disposed concentrically around the central wire and having a proximal end and a distal end, the distal end of the sheath having a lumen of sufficient diameter to slide over the proximal portion of the filter.

24. The vascular filter arrangement according to claim 23, wherein the filter comprises a wire structure having a porous membrane attached thereto.

25. The vascular filter arrangement according to claim 23, wherein the proximal end of the filter is slidably linked to the central wire by a radiopaque marker or a crimping band and the distal end of the filter is fixedly attached to the central wire by a radiopaque marker or crimping bands.

26. The vascular filter arrangement according to claim 23, wherein the proximal end of the filter is fixedly linked to the central wire by a radiopaque marker or a crimping band and the distal end of the filter is slidably linked to the central wire. by a radiopaque marker or crimping bands.

27. The vascular filter arrangement according to claim 24, wherein the filter membrane is linked to only the distal portion of the wire structure.

28. The vascular filter arrangement according to claim 23, wherein the distal end of the central wire comprises a flexible tip.

29. The vascular filter arrangement according to claim 23, wherein the proximal end of the sheath is linked to a handle.

30. A vascular filter arrangement comprising: a central wire having a proximal end and a distal end, and a filter arranged concentrically about said central wire, said filter having a proximal end and a distal end, the distal end being of the filter linked to the central wire adjacent to its distal end and the proximal end of the filter being connected to the central wire.

31.- The vascular filter arrangement according to claim 30 which also comprises a sheath disposed concentrically around the central wire having a proximal end and a distal endthe distal end of the sheath having a lumen of sufficient diameter to slide over the proximal portion of the filter.

32. The vascular filter arrangement according to claim 30, wherein the filter comprises a wire structure having a porous membrane attached thereto.

33. The vascular filter arrangement according to claim 32, wherein the filter membrane is linked only to the distal portion of the wire structure.

34. The vascular filter arrangement according to claim 30, wherein the proximal end of the filter is fixedly attached to the central wire by a radiopaque marker or a crimping band and the distal end of the filter is slidably linked to the central wire. by a radiopaque marker or a crimping band.

35.- The vascular filter arrangement according to claim 30, wherein the proximal end of the filter is slidably linked to the central wire by a radiopaque marker or a crimping band and the distal end of the filter is fixedly attached to the central wire by a radiopaque marker or a crimping band.

36.- The vascular filter arrangement according to claim 35, wherein the distal end of the filter is inverted proximally.

37.- The vascular filter arrangement according to claim 36, which also comprises a sliding component on the central wire for folding the filter in order to trap residues or emboli.

38.- A filter for a vascular apparatus comprising a support structure formed by two or more support components, each of which has a proximal end and a distal end, in which the respective proximal end and the distal end they are held together, and a filter membrane comprising a flexible polymer material having the same holes formed by laser, spaced regularly.

39.- The filter according to claim 38, wherein the polymeric material is polyurethane, polyethylene, or a copolymer thereof.

40.- The filter according to claim 38, wherein each of the holes has a diameter comprised between approximately 50 microns and approximately 300 microns.

41. The filter according to claim 40, wherein the holes are of uniform size and are spaced vertically and horizontally from each other so that the center-to-center spacing is between approximately 1.2 times and 1.6 times. times the diameter of the holes.

42. The filter according to claim 40, wherein the holes comprise between approximately 10% and 50% of the filter surface.

43.- A method of preparing a filter useful for vascular applications in which a membrane is positioned in a stable manner, a laser generating apparatus is positioned adjacent to said membrane, and laser flashes are directed to the membrane in a predetermined configuration to produce holes spaced regularly in said membrane.

44.- A vascular filter arrangement comprising: a central wire having a proximal end and a distal end, a filter arranged concentrically around said central wire, said filter having a proximal end and a distal end, the distal end of the filter being filter fixedly attached to the central wire, and a sheath disposed concentrically around the central wire and positioned distally to the filter component, said sheath having an open proximal end and a closed distal end, the proximal end of the sheath having a lumen of sufficient diameter to slide over the distal portion of the filter.

45.- The vascular filter arrangement according to claim 44, wherein the filter comprises a wire structure having a porous membrane attached thereto.

46.- The vascular filter arrangement according to claim 44, wherein the proximal end of the filter membrane is slidably linked to the central wire by a protective ring.

47.- The vascular filter arrangement according to claim 45, wherein the filter membrane is only linked to the distal portion of the wire structure.

48. The vascular filter arrangement according to claim 44, wherein the distal end of the central wire comprises a flexible tip.

49.- The vascular filter arrangement according to claim 44, wherein the proximal end of the sheath is linked to a handle.

50.- A vascular filter arrangement comprising: a central wire having a proximal end and a distal end, a sheath disposed concentrically around the central wire and having a proximal end and a distal end, and a filter arranged concentrically about said central wire, said filter having a proximal end and a distal end, the distal end of the filter being fixedly attached to the central wire adjacent to its distal end and the proximal end of the filter being fixedly attached to the distal end of the filter. Sheath

51. The vascular filter arrangement according to claim 50, wherein the filter comprises a wire structure having a porous membrane attached thereto

52. The vascular filter arrangement according to claim 50. , wherein the filter comprises a wire structure having a porous membrane attached thereto.

53. - The vascular filter arrangement according to claim 51, wherein the filter membrane is only linked to the distal portion of the wire structure. 54.- The vascular filter arrangement according to claim 50, wherein the distal end of the central wire comprises a flexible tip. 55.- The vascular filter arrangement according to claim 50, wherein the proximal end of the sheath is linked to a handle. 56.- The vascular filter arrangement according to claim 50, wherein the proximal end of the filter is fixedly attached to the sheath by adhesive.