JPH11318910A - Atraumatic anchoring and disengagement mechanism for permanent implanting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thrombosis filter that can be implanted and fixed in a specified position in a vein and recovered through an endovenous route even after the formation of neointima hyperplasia. SOLUTION: Atraumatic anchoring and disengagement mechanism for a permanent implanting device comprises a plurality of thrombosis filter means 46 for holding thrombotic substance moving in a second direction at the time of being spread out in a first direction; a plurality of positioning means 62 connected to the thrombosis filter means 46 and having a plurality of corresponding wall surface engaging means 64, 66 engaged with corresponding lumen internal walls and spread out in the second direction to limit motion into the second direction; and a retracting means for retracting a plurality of positioning means and thrombosis filter means in response to control applied percutaneously from the outside for disengagement in the second direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an improved filter for thrombosis. More particularly, the present invention relates to a thrombotic filter that can be placed percutaneously at a selected location within a selected body cavity of the vascular system and that is used to trap thrombotic material or clots. . Even more particularly, the present invention relates to a thrombosis filter that can be percutaneously removed from the vascular system in one direction.

[0002]

2. Description of the Prior Art Pulmonary embolism is recognized as a medical emergency and may be due to venous thrombosis. This venous thrombosis is caused by stasis in blood flow, damage to the lining of the vein, or abnormal blood coagulation. Well-known treatments include anticoagulant drug therapy, thrombolytic therapy,
Includes thrombectomy and inferior vena cava filtration. When the inferior vena cava filtration method is selected, the filtration method can be performed by making an abdominal incision under general anesthesia or percutaneously inserting a thrombosis filter under local anesthesia. Abdominal wall incision is a surgical procedure performed under general anesthesia. Before such an operation, therapy with an anticoagulant is stopped, so that a thrombus is easily formed.

A well known option is to insert a thrombosis filter into the vascular system, especially the inferior vena cava,
In this case, only local anesthesia is required. Although percutaneous insertion of filters has been accepted as an effective procedure because it requires only local anesthesia, such thrombotic filters have a new intimal hyperplasia in a relatively short time after implantation. It has been recognized that this may result in attachment to the vena cava or the inner wall of the vein. This process takes place within two or three weeks, and in the prior art, the filters are positioned so that the filter cannot be removed with a single percutaneous procedure to prevent serious trauma to the vessels. .

[0004] A number of thrombosis filters have been developed to allow percutaneous removal. In these prior art thrombosis filters, forces are likely to be distributed along the length of the strut, including those with substantially straight struts. As the struts diverge outwardly and engage the lumen wall, asymmetric pressure is applied to the lumen, thereby forcing the struts to collect in such a way that the struts damage the lumen.

As indicated, there are a number of prior art implantable filters. One example is the filter disclosed in U.S. Pat. No. 4,817,600 to James Kay Herms et al., Which focuses at one end and forms an acute angle with the axis of the filter. And a set of legs shaped to form a generally conical arrangement. The shaping leg includes a hook at the tip for fastening to the vein wall and for holding the filter in place against the blood flow in the lumen. Provide an improved leg construction that overcomes some of the problems associated with filters using relatively straight struts, resulting in vessels or lumens that result from lightly touching or tilting the filter Damage was minimized. However, the patent did not describe a structure or method for transcutaneously removing the filter.

[0006] US Patent No. 4,990,156 to J. Lefebvre describes the purpose of temporary use to determine whether treatment by more permanent filtration is necessary. Describes a filter that can be inserted percutaneously. This device describes the contact between the non-invasive filter element and the vessel, and describes a number of elements, each with a sharp, roughened portion, which contacts the vessel wall to secure the filter in place. Says. If this filter does not need to be used permanently, the sheath is removably disposed. Once the filter has been opened, it is positioned for final use and should not be easily removed thereafter.

[0007] Erik Rasmusse
U.S. Pat. No. 5,324,304 to n) describes another form of implantable filter, which is automatically expandable and can be inserted through a catheter surrounding its structure. it can. The anchor legs of the filter are designed with hooks at the ends to engage the vein wall once deployed. The anchor element forms part of the filter structure and, once deployed, tends to stay firmly on the vein wall. No structure or method for percutaneous removal is described.

[0008] US Patent No. 5,370,657 to Toshiyuki Irie describes a retrievable thrombosis filter in which a retaining device and a filter device are provided with an intermediate heart. It is formed from a number of opposing elements held in place by the body. The patent recognizes that removal may be desirable and describes a set of ends that are shaped to engage the vessel wall without penetrating the vessel wall deeply. For removal, a percutaneous procedure must be performed in duplicate from opposite ends of the filter. A pair of hook devices are hooked from opposite ends and the two filter halves are pulled apart until the connecting core breaks. While the two filter halves are retracted and housed in a pair of sheaths, this removal procedure requires two opposing removal structures to be applied to opposing ends of the filter, and the two removal devices are The filter must be adjusted to grip the opposing hook elements so that the filter is retrieved in half. This removal method doubles the risk to the patient and is relatively difficult to achieve due to the small size of the elements.

The foregoing prior art is illustrative of various types of filters and handling devices known for use in installing and removing thrombotic filters. The prior art construction does not describe a filter construction that can be easily removed using a single percutaneous removal procedure.

[0010]

SUMMARY OF THE INVENTION In order to address the problems in the prior art, the present invention has been developed and has been in place for a period of time, even after being left in place for sufficient time for new intimal hyperplasia to develop sufficiently. It is an object of the present invention to provide an improved retrievable thrombosis filter which can be removed through a percutaneous procedure. By using a new retaining structure and filter portion for the thrombosis filter, the filter is retracted such that the retaining portion can be folded from one end by external manipulation, and the entire filter is retracted into an enclosure for removal. It is configured as follows.
These and other more specific objects of the present invention will become apparent to one of ordinary skill in the art in view of the drawings and the description of the preferred embodiments.

[0011]

SUMMARY OF THE INVENTION The present invention includes a recoverable thrombosis filter that can be recovered in a single recovery procedure. The filter is formed in a predetermined manner and includes a plurality of thrombosis filter elements that are clustered at one end and are scattered about a long axis to form a generally conical structure. The filter element includes an end shaped to engage a lumen inner wall. One end of each of the plurality of positioning posts is converged, and the plurality of positioning posts are scattered about the long axis in the opposite direction.
The locating strut includes an end for engaging a wall surface, the end including a protrusion engaging the inner lumen wall to prevent movement of the filter structure in a direction in which the locating strut diverges. The anchor devices used herein can also be used with other devices such as stents, stent grafts, vaso-occlusive particles, vascular closure devices, and filters.

The collection device including the retracting structure is percutaneously inserted near the filter. The retrieval device includes an extensible gripping device, an actuator, and an outer shield capable of surrounding the filter. The gripper is operated to engage a portion of the retraction structure so as to hold the filter in place. The actuating device of the retrieval device functions to fold the positioning struts into a position where they can be retracted into the outer shield by the gripping device. While the outer shield is held firmly in place, the gripping device is further retracted and a plurality of thrombosis filter structures are retracted into the shield.

In one embodiment of the retrievable structure for a thrombosis filter, by coordinating the retraction device and the retrieval device, the plurality of locating struts are disengaged from contacting the lumen inner wall and are moved in the initial spreading direction. Folded in a substantially parallel relationship with the columns arranged vertically.

In another embodiment, the retrieval device engages a retrievable thrombosis filter and is held in place while the plurality of positioning struts are moved in a direction opposite to the initial spreading direction. , Arranged in generally parallel directions along the long axis, oriented in the direction of spreading of the filter elements. Once folded, the outer shield is locked in place and the filter is retracted into the outer shield.

Thus, the present invention is an improved retrievable thrombosis filter and method of removal that permits percutaneous removal of the filter by a retrieval device that engages one end of the filter. Further features of the invention, the advantages derived therefrom, and the various scopes and aspects of the invention are illustrated in the drawings,
It will be apparent from the description of embodiments of the invention and the appended claims.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a partial sectional view of a human body from the left end to the right end, showing a medical procedure for installing a filter for thrombosis in the inferior vena cava and percutaneously entering the venous system from the jugular vein. A medical procedure for removing the filter by retracting the filter will be described. Here, body 10
The notch 12 exposing a part of the vascular system will be exemplified. Femoral vein 14 leads to external iliac vein 16. The common iliac vein 18 leads to the inferior vena cava 20. As shown in notch 22, filter 24 extends into the inferior vena cava and is fixed in place by the structure described below. As shown, the catheter tube is incised 2
From 8 is inserted into the vascular system. When the catheter tube is extended toward the heart 30, it reaches the inferior vena cava 20,
Then the filter 24 is opened. The distal end 32 of the catheter structure 26 is exposed after the filter 24 has been opened. To retract or remove the filter 24, a retrieval device (36) is inserted through the incision 40 into the jugular vein 38.
After passing through the atrium of the heart 30, the distal end 42 of the retrieval device enters the inferior vena cava 20. Although this figure does not show the collecting device in detail, it will be described in detail below.

FIG. 2 is a cutaway side view of the filter in the relaxed position. The filter 44 comprises a plurality of shaped filter elements 46, each having an attachment end 48 and a vessel wall engaging end 50. The protrusion 52 is long enough to engage the corresponding vein wall (not shown), but short enough not to penetrate the vein.

The joining structure 54 has a frustum-shaped end 56,
This end is adhered and fixed to the mounting end 48. Structure 54 defines an elongated cavity 58 in which mounting member 60 is slidably held.

A plurality of flexible anchor posts 62 are mounted on the mounting member 60 and project outwardly to the vessel wall engaging surface 64. The protrusion 66 serves to position and hold the filter 44 in place when engaged with the vein lining. Hook element 68 is mounted on mandrel 70. The end 72 of the mandrel 70 is fixed within the joint structure 56. The tubular member 74 has one end fixed to the push structure 76 and the other end 78 attached to the attachment member 60. Tubular member 74 surrounds mandrel 70, which are coaxially aligned together.

In the relaxed state, length L1 from protrusion 52 to protrusion 66 is about 5.1 cm (about 2.0 inches). The length L2 of the joining member 54 is about 1.0c
m (about 0.4 inches). Length L3 from end to end
Is about 3.2 cm (about 1.25 inches), and the distance L4 from protrusion to protrusion is about 3.0 cm (about 1.2 inches). Various shapes and configurations are described below, but if the filter portion indicated by dashed line 78 is diverged, and if blood is flowing in the direction of arrow 80, the filter portion will restrict the flow of a clot or thrombus. It is understood that it acts to At the same time, the positioning and retaining portions 82 limit longitudinal and lateral movement of the filter 44 within the corresponding lumen or vein. Preferably, the retaining portion 82 centralizes the device within the lumen.

FIG. 3 is a partial perspective view of the end of the filter leg member engaging the vein. The end 50 is generally curvilinear and the end 50 is flattened to a desired dimension so that the lower surface 84 slidably engages the corresponding vein wall. The thickness of the end 50 is selected for the desired flexibility.

The outer projection 52 is arranged to engage the vein wall. A similar shape is used for the anchor element. FIG. 4 is a side view of the ribbon wire leg member. The filter member 46 is formed so as to form a predetermined angle.
And a mounting end 48 disposed in the longitudinal direction. At the other end, the curved portion 84 bends in the opposite direction to the mounting end 48 and has a protrusion 52.

FIG. 5 is a sectional view taken along line 5-5 in FIG. In one embodiment, the flat wire has a thickness T1 of about 0.006 inches and a width W1 of about 0.026 inches. It is understood that varying the thickness relative to the width causes the filter element to be flexible.

FIG. 6 is a side view of a round leg member. Again, there is a bend 48 'in the leg member, which is approximately
It may have a top thickness T2 of about 0.016 inches. The lower cross section is reduced, and the thickness T3 of the cross section is about 0.006 inches.

FIG. 7 is a sectional view taken along the line 7-7 in FIG. This figure illustrates the degree of flexure of flexure 48 '. FIG. 8 is a plan view of a snake-shaped leg member. As shown, a snake-shaped portion 86 is provided and, when used in combination with other filter members, improves the filter function.

FIG. 9 is a plan view of a spiral leg member.
In this alternative embodiment, the helical portion 88 is used to enhance filtering. FIG.
10 is a partial perspective view taken along line 10-10 in FIG. This figure illustrates the helical portion 88. The design of the snake-shaped portion 86 or the helical portion 88 is selected according to the number of filter elements used, the overall size of the filter 44, the characteristics of the lumen in which the filter is located, and the flow rate of the blood to be filtered. .

FIG. 11 is a cut-away side view of a filter disposed within a lumen in a state where it is about to be hooked for removal. Positioning part 82 and filter part 78
Note that each has a curved portion within the vein 90. When curved, the curved engagement portion 50 comes into contact with the inner wall 90 of the blood vessel. The contact portion 64 of the positioning portion 82 also makes contact with the inner wall 90 of the blood vessel. With this arrangement, the positioning portion 82 and the filter portion 78 are separated from the vein wall 90.
And the protrusion 52 and the protrusion 66 are engaged with the inner wall without puncturing the inner wall of the blood vessel.

The filter retrieval device 92 is inserted in the direction of arrow 94 and is moved until the gripper 96 is near the hook element 68. Snare 96 is an annular strap or wire that can be manipulated from outside to hook mandrel 70 behind hook element 68. In one embodiment, hook element 68 and gripper 96 are formed from a material that can be detected by a fluoroscope.

FIG. 12 is a cutaway side view of a filter positioned within a lumen with a positioning portion folded for removal. When the extensible gripping device 96 is engaged with the member 68, the device 96 can be used to hold the member 68 in a relatively stable longitudinal position.
When positioned in this manner, the actuator 98 is moved in the direction of arrow 100 to engage the element 76, thereby moving the tube 74 along the mandrel 70 and folding the positioning portion 82. When the mounting element 60 is moved into the cavity 58, folding occurs and the positioning elements are arranged substantially parallel along the long axis.

FIG. 13 is a cutaway side view of the filter disposed in the lumen with the positioning portion surrounded by the collection device. Once the positioning portion 82 is folded, the outer shield 102 is moved in the direction of arrow 104, but the gripping device is held firmly. When so positioned, outer shield 102 is positioned to engage filter element 78 at end 106.

FIG. 14 is a cutaway side view of the filter placed within the lumen with the entire filter surrounded by the collection device and ready for removal. Once the positioning portion 82 is surrounded by the outer shield 102, pressure is applied to the gripping member 96 to move the gripping member 96 in the direction of arrow 108. With this movement, the outer shield 102 is firmly held, and the end 106 is
It acts to fold filter portion 78 such that filter portion 78 is retracted inside 02. When completely retracted inside the collection device 92, the length L5 of the collection device 92, which is relatively stiff compared to other portions, is about 7.04 cm (about 2.77 inches).

FIG. 15 is a cutaway side view of another embodiment of the filter in the relaxed position. Elements having similar functions are indicated by similar reference numerals. In this embodiment, the filter portion 78 is attached to the attachment structure 110 while being joined to the inside of the member 54. In this configuration, the frustum-shaped element 56 has been eliminated, increasing the strength in this structure. Hook 112 is replaced with button-shaped element 68. The push element 76 of FIG. 2 is replaced by a frustum push element 114. With this frustum shape,
Blood flow is better and flow disturbances are minimized. In addition, this configuration further increases the size of the mandrel 70 in the direction of the mandrel so that the mandrel tends to tilt when moving the mandrel forward as previously described. In this embodiment, the dimensions of L2, L3, L4 are similar to those described with respect to FIG. The protrusion to protrusion length L6 is about 5.3 cm (about 2.1 inches), and the end-to-end length L7 is about 5.64 cm (about 2.60 inches).
22 inches). The total length of the filter when relaxed is L8
Approximately 2.68 inches (6.81 cm)
It is.

FIG. 16 is an end view of the joining member taken along line 16-16 in FIG. This figure illustrates the housing 54 with the positioning element 62 fitted. Same element 6
Numeral 2 consists of four in this embodiment and surrounds a mandrel 70 passing therethrough. This figure is an enlarged view and is not scaled.

FIG. 17 is an end view of the joining member taken along line 17-17 in FIG. This figure illustrates the mounting member 110 mounted on the joint housing 54 and shows that there are six mounting ends 48 of the filter member. The mandrel 70 is fixed to the mounting member 110. This figure is also shown in FIG.
The scale is different from 5.

FIG. 18 is a cutaway side view of a further embodiment of the filter in the relaxed position. In this embodiment, the mounting element 60 is fixed in the groove 58 substantially adjacent to the mounting member 110. Positioning column 62
Mounting end 78 is constrained by an outer boundary of housing 54. The hook 112 is fixed to the mandrel 70,
Mandrel 70 is also secured within mounting element 110. In this embodiment, the housing 54 is shorter than the embodiment shown in FIG. 2 and the length L9 is about 0.673 cm (about 0.23 cm).
65 inches). Overall length L1 from protrusion to protrusion
0 is about 4.85 cm (about 1.85 inches) and has a length L from the end of the mounting member 110 to the filter portion 78.
11 is about 3.23 cm (about 1.27 inches). The interval L12 when the filter portion is relaxed is about 3.0 cm (about 1.2 inches). The manner in which the anchor element 62 is released and folded in this embodiment is described below.

FIG. 19 is a cutaway side view of the filter of FIG. 18 disposed within a lumen. As shown, the positioning portion 82 is similar to the filter portion 78 in that the
0 is engaged. When housed in this manner, the diameter L13 of the lumen or vein is about 0.866 inches. When the filter is installed, the total length L14 is about 5.72 cm (about 2.25 inches), while the length L15 from the tip protrusion to the protrusion is 5.36 cm.
(About 2.11 inches).

FIG. 20 is a cutaway side view of the filter of FIG. 18 hooked for removal. In this embodiment, the retrieval device 120 comprises a gripping device 122 for engaging the hook 112. When engaged in this way, the gripping device is securely held inside and the outer shield 12
4 is extended in the direction of arrow 126 and hooked on leg 62 of positioning portion 82. Outer shield 24 may include a funnel-shaped end to assist in directing the filter toward collection device 120.

FIG. 21 is a cutaway side view of the filter of FIG. 18 having a positioning portion surrounded by a collection device.
As shown, the outer shield 124 is moved in the direction of arrow 126 such that the retrieval device 120 causes the positioning post 62 to bend over itself and enter the outer shield 124. With this arrangement,
The struts 62 are substantially parallel to each other and are located along the length of the filter and collection device 120. When the positioning portion is folded and retracted in this way, the gripping device 1 is used to secure the outer shield 124 and then to retract the filter portion 78 into the outer shield 124
22 is moved in the direction of arrow 128. When the filter portion 78 is completely retracted into the outer shield 124, the retrieval device 120 can be removed from the body.

FIGS. 22A to 22E show the deflection and contraction of a flexible anchor member of the type used in the filter of FIG. In FIG. 22A, the flexible anchor member 62 is in a position retained on the vein inner wall 90. The outer shield 124 applies a force in the direction of the arrow 130 to the portion of the flexible anchor member 62 (see FIG. 21), so that the tip 64
And the protrusion 66 starts to move away from the inner wall 90 in one direction. In FIG. 22B, when a force is applied at a location indicated by an arrow 130, the flexible anchor member 62 starts to bend. In this case, the protrusion 66 comes off the inner wall 90, and the tip 64 starts to slide along the inner wall. In order to control the position of the bending caused by the force applied to the arrow 130, the anchor member 62 may be provided with a predetermined region having high flexibility.

In FIG. 22C, the force applied to arrow 130 causes flexible anchor member 62 to bend, but end 64 can move only along inner wall surface 90. FIG. 22D shows that the force applied in the direction of arrow 130 reaches the point where the flexible anchor member 62 begins to bend over itself, such that the distal end 64 no longer contacts the intravenous wall 90. Finally, in FIG. 22E, a force is applied by the outer shield 124 in the direction of the arrow 130 so that the flexible anchor member 6
2 is shown folded over itself so that the outer shield can pass over the same member 62.

FIG. 23 is a side view of still another embodiment of a recoverable filter according to the present invention. The filter shown in FIG. 23 is in a relaxed, uncompressed state. The filter of FIG. 23 is substantially similar to the filters of FIGS. 15-22, except that the following description is based on FIG.
Except where the description differs from that of the fifth embodiment.

The filter of FIG. 23 includes a plurality of filter elements 146 having ends 150 that engage the vessel wall. The wall engaging end 150 shown in this embodiment is curved and presents a curved convex surface to the vein wall. The filter elements 146 collectively form a filter portion or filter array 178. Filter array 17
At the end of 8, a plurality of legs or anchor posts 162 are located. The anchor post 162 has a proximal end and a distal end. A representative end is shown in detail in FIG. The filter also includes a hook 212 that helps remove the filter from the vein. The joining member 154 joins the filter array 178, the vicinity of the base of the column 162, and the hook 212 together. The support 162 is preferably formed in a ribbon shape.
The width is a direction perpendicular to the thickness, that is, a direction perpendicular to the paper surface.

FIG. 24 is a detailed view of the end of the column 162. This end view shows a sharp section 166 and a sharp section 16.
A pad portion extending beyond 4 to the end
164. Sharp portion 164 is sharp enough to puncture the vein wall. The contact portion 164 is preferably in the form of a ribbon like the column 162, and the thickness thereof is shown in FIG.
4, the width is a direction perpendicular to the thickness, that is, a direction perpendicular to the paper surface. As seen in FIG.
The thickness of the abutment portion 164 decreases toward the distal end. The decrease in the thickness of the contact portion 164 allows the contact portion 1 to be reduced.
The flexibility of the distal end of the 64 can be increased. By changing the properties of the material of the contact portion 164,
Flexibility at the distal end along the abutment 164 can be similarly increased. It is desirable that the abutment portion 164 be sufficiently flexible so as not to puncture the vein wall. That is, it is desirable that the contact portion 164 be non-traumatic.
In a preferred embodiment of the present invention, the length of the sharp portion 164 is between about 2-6 mm, and the length of the contact portion 162 is between about 4-20 mm. In a preferred embodiment, the length of the contact portion 164 is greater than twice the length of the sharp portion 164.

FIGS. 25 and 26 show that during normal use,
24 shows the filter of FIG. The direction of the blood flow is indicated by arrow B. The filter is hook 21
2 and is removed in the direction indicated by arrow C. Filter element 146 is moderately compressed as compared to the relaxed state shown in FIG. As shown in FIG. 26, the sharp portion 166 punctures the wall of the blood vessel A, and the contact portion 164 is generally parallel to the wall surface of the blood vessel A.

FIGS. 27 and 28 show FIGS. 2A and 2B being removed from blood vessel A in the direction indicated by arrow C.
3 shows a filter. When the filter is collected using the same method as the filter method of FIG.
Will generally deform, as shown in FIGS. 22A-22E. The column 162 shown in FIG. 27 is located near the column 62 in FIG. 22B. If the operation is continued, the support 16
2 is generally assumed to be in the position shown in FIG. 22E.
Final filter removal is completed as described above for the filter of FIG.

FIG. 28 is a detailed view of the distal end of the column shown in FIG. The shape of the support 162 in FIG.
It can be seen that the shape of the strut 62 in 2B is similar, but the length of the abutment portion 164 for the sharp portion 166 is substantially greater than the length of the element 64 for the element 66 in FIG. 22B. Increasing the length of the distal end of the abutment portion 164 or increasing its flexibility provides a cantilever that is effective to retract the sharp portion 166 from the wall of the vessel A.

FIG. 29 is a side view of a filter 200 according to yet another embodiment of the present invention disposed inside the blood vessel A. Filter 200 has a major axis D. The blood flow in the blood vessel A, that is, the flow of the fluid, is shown in the direction indicated by the arrow B. The filter 200 moves the hub 204 in a first direction along the major axis D but away from the major axis D.
And a flexible post 202 extending from the support. Prop 2
02 has a first end connected to the hub 204. Prop 2
The second end 206 of 02 is preferably sharp and barbed to engage the wall of blood vessel A.

The filter 200 includes the column retracting member 20.
8 is also included. Strut retraction member 208 includes a plurality of retraction loops 210 extending from retraction member hub 212 in a second direction generally along axis D. Preferably, each loop 210 forms a loop around the column 202. Mooring coupler 214 extends from hub 212 in a first direction along axis D. The telescopic coupler 216 couples with the hub 204 and the retraction member hub 212.

Various elements of filter 200, such as struts 202 and loops 210, can be formed from Nitinol, stainless steel, or other biocompatible materials. It will be appreciated by those skilled in the art that other filter embodiments are also desirably provided with the materials described above to construct embodiment 200.

FIG. 30 is an end view of the filter 200 shown inside the blood vessel A. In the embodiment illustrated by the filter 200, there are six columns 202 and six loops 210 each.

FIG. 31 is a side view of the filter of FIG. 29, in which a mooring section 218 with a loop is
Has been tied to. The mooring portion 218 includes an outer tubular member 224
And an inner tubular member 226 disposed within a catheter 222. For example, assuming that filter 220 is placed in the inferior vena cava, catheter 222 may be advanced from the femoral vein access point toward the filter. Outer tube 224 and inner tube 226 are preferably formed from biocompatible materials, including polymers, well known to those skilled in the art. The material desirably has sufficient strength and rigidity or flexibility to perform the procedures described below.

FIG. 32 is a side view of the filter of FIG. 29, wherein the retraction member 208 has been pulled in the first direction, and the loop 210 advances and engages the post 202. FIG. 33 is a side view of the filter 200 of FIG. 29, where the inner tube 22 of the catheter 222 is shown.
6 is engaged with the loop 210. In the dashed line, the inner tube 226 is shown traveling in a second direction over the loop 210, and the strut 202 is moved from the first position engaging the wall of the blood vessel A to the axis D of the filter 200. Has been moved to a second position close to.

FIG. 34 shows the filter 20 shown in FIG.
0 is a side view. In FIG. 34, the support 202 is the second
It is located at the position. Second end 20 of strut 202
6 is in contact with the distal end of the inner tube 226.

FIG. 35 is a side view of the filter 200 of FIG. 29, wherein the filter 200 is housed in the outer tube 224 of the catheter 222. Filter 20
O may be removed from the patient through outer tube 224, or filter 200 and catheter 222 may be removed from the patient simultaneously.

By performing the removal steps in reverse order,
It can be seen that a method of placing the filter 200 in the blood vessel A as shown in FIG. 29 will be provided. However, in a preferred method, the filter 200
Before placing the hub in the catheter 222, the hub 204 and the hub 212 are separated as shown in FIG. After the filter 200 is spread out as shown in FIG.
8 and catheter 222 can be removed from the patient, so that filter 200 can be left in place for an extended period of time. From the foregoing, it can be seen that the various forms and choice of materials provide a suitable retrievable filter structure that can be utilized in accordance with the inventive concepts described herein. Is done. In general,
This material must be suitable for implantation in the human body and must be intact (intac
t) leave it. The choice of material also determines the flexibility and elasticity of the various members. The various components that make up the filter can be formed from a class of elastic materials including Nitinol, stainless steel, platinum, tungsten, titanium, and chromium alloys. In forming the thrombosis filters of the type just described, molded or bonded structures may be utilized.

While various embodiments and methods of the present invention have been described with reference to the drawings, it will be appreciated that the various objects set forth above have been attained, and that various changes and extensions have been made within the spirit and scope of the invention. It can be appreciated that it is obvious to a trader. Therefore, what should be protected by a patent,
It is set forth in the appended claims.

[0057]

According to the present invention, a recoverable thrombosis that can be removed through a single percutaneous procedure even after being left in place for a period sufficient to allow new intimal hyperplasia to fully develop An improved type of filter can be provided.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional view of the human body from the left end to the right end, showing a medical procedure for installing a filter for thrombosis in the inferior vena cava and a filter percutaneously entering the venous system in the jugular vein to retract the filter. Explain the medical procedure to be removed.

FIG. 2 is a cutaway side view of the filter in a relaxed position.

FIG. 3 is a partial perspective view of the vein engaging end of the leg member of the filter.

FIG. 4 is a side view of a ribbon wire leg member.

FIG. 5 is a sectional view taken along the line 5-5 in FIG. 4;

FIG. 6 is a side view of a round leg member.

FIG. 7 is a sectional view taken along the line 7-7 in FIG. 6;

FIG. 8 is a plan view of a snake-shaped leg member.

FIG. 9 is a plan view of a spiral leg member.

FIG. 10 is a partial perspective view taken along line 10-10 in FIG. 9;

FIG. 11 is a cut-away side view of a filter placed in a lumen while being hooked for removal.

FIG. 12 is a cutaway side view of a filter disposed within a lumen with a positioning portion folded for removal.

FIG. 13 is a cutaway side view of a filter disposed in a lumen with a positioning portion surrounded by a collection device.

FIG. 14 is a cutaway side view of a filter placed within a lumen with the collection device enclosing the entire filter and ready for removal.

FIG. 15 is a cutaway side view of another embodiment of the filter in a relaxed position.

FIG. 16 is an end view of the joining member taken along line 16-16 in FIG. 15;

FIG. 17 is an end view of the joining member taken along line 17-17 in FIG. 15;

FIG. 18 is a cutaway side view of a further embodiment of the filter in a relaxed position.

FIG. 19 is a cutaway side view of the filter of FIG. 18 disposed within a lumen.

FIG. 20 is a cutaway side view of the filter of FIG. 18 hooked for removal.

FIG. 21 is a cutaway side view of the filter of FIG. 18 with a positioning portion surrounded by a collection device.

FIGS. 22 (A) to (E) show the deflection and contraction of the flexible type anchor member used in the filter of FIG.

FIG. 23 is a side view of yet another embodiment of a recoverable filter according to the present invention.

FIG. 24 is a detailed view of the anchor post end of the filter of FIG. 23.

FIG. 25 is a side view of the retrievable filter of FIG. 23 disposed in a lumen.

FIG. 26 is a detailed view of the end of the anchor strut shown in FIG. 25.

FIG. 27 shows the operation of removing the filter from the lumen;
FIG. 24 is a side view of the retrievable filter of FIG. 23 shown in a lumen.

28 is a detailed view of the distal end of the anchor strut shown in FIG. 27.

FIG. 29 is a side view of yet another embodiment of a recoverable filter according to the present invention.

FIG. 30 is an end view of the filter of FIG. 29.

FIG. 31 is a view of the filter and removal catheter of FIG. 29.

FIG. 32 is an illustration of the filter of FIG. 29 at the beginning of the removal operation.

FIG. 33 is a view of the filter of FIG. 29 at a stage in the removal operation following the view shown in FIG. 32;

FIG. 34 is a view of the filter of FIG. 29 at a stage in the removal operation following the view shown in FIG. 33;

FIG. 35 shows the filter of FIG. 29 retracted into a removal catheter.

[Explanation of symbols]

24: filter, 46, 146: molded filter element, 50, 150: vascular wall engaging end, 52: protrusion, 5
4, 154 joining structure, 62 positioning element, 64 blood vessel wall engaging surface, 66 protrusion, 68, 112, 212 ...
Hook element, 70: mandrel, 74: tubular member, 76: push structure, 92: filter collection device, 96: gripping device, 9
8 Actuator, 162 Support, 164 Contact part, 16
6 ... Sharp part, 208 ... Retraction member, 210 ... Loop, 216 ... Expansion connector, 218 ... Mooring part, 220 ... Loop, 224 ... Outer tube, 226 ... Inner tube.

Continued on the front page (72) Inventor Ostrowskiy, Issac United States 02181 Wallace Ray Willow Street, Mass. 5 (72) Inventor Wallace, Michael Jay. United States 77401 Belaya Linden, Texas 4922 (72) Inventor Kim, Hannah United States 01719 Boxborough, Massachusetts Old Orchard Lane 119 (72) Inventor Shank, Peter United States 01505 Massachusetts, Boylston Mile Hill Road 214 (72) Inventor Di Matteo, Christian United States 01754 Maynard Maine, Massachusetts Street 176 a

Claims (52)

[Claims] 1. A method comprising: a. Second when spread in the first direction
A plurality of thrombosis filter means for retaining thrombotic material traveling in the direction of b. A plurality of positioning means coupled to the thrombosis filter means, the positioning means engaging with a corresponding lumen inner wall and in the second direction to restrict movement in the second direction; Having a corresponding plurality of deployed wall-engaging means; c. Retrievable means for retracting the plurality of positioning means and the plurality of thrombosis filter means in response to externally percutaneously applied control for removal in the second direction. Improved filter. 2. The filter according to claim 1, wherein said retracting means includes folding means for folding said plurality of positioning means in said second direction. 3. The retraction means comprising: a. Holding means for securely holding the plurality of positioning means in the longitudinal direction; b. 3. The filter of claim 2, further comprising: propulsion means for directing the plurality of engagement means in the second direction and forcing the plurality of positioning means into a substantially parallel arrangement. 4. The plurality of positioning means and the plurality of thrombosis filter means for removing the plurality of positioning means and the plurality of thrombosis filter means in the second direction. 4. The filter of claim 3, further comprising surrounding wrapping means. 5. The filter according to claim 1, wherein said retracting means includes a bending means for bending said plurality of positioning means in said first direction. 6. The retraction means comprising: a. Holding means for securely holding said plurality of positioning means in the longitudinal direction; b. 6. The filter according to claim 5, further comprising folding means for directing the plurality of engaging means in the first direction, and folding the plurality of positioning means in a substantially parallel arrangement. 7. The retraction means includes the plurality of positioning means and the plurality of thrombosis filter means for removing the plurality of positioning means and the plurality of thrombosis filter means in the second direction. 7. The filter of claim 6, further comprising surrounding means for surrounding. 8. A method for retrieving an implanted filter from a patient's vein, said filter comprising: a filter portion comprising a plurality of shaped filter elements; and a flexure flared to engage an inner vein wall. A filter comprising: a locating portion comprising a flexible anchor member; and a joining member joining the filter portion to the locating portion and having a securing device, the method comprising: Percutaneously inserting a retrieval device comprising an extensible grasping device, an actuating device, and an outer shield capable of surrounding the filter, wherein the inserted device is guided to a filter implanted intravenously. B. Advancing a collection device to near the fixation device; c. Externally operating the fixation device to couple the gripping device and the fixation device, and holding the fixation device in place; d. Stretching the actuator and folding the plurality of flexible anchor members; e. Retracting the filter into the outer shield; f. Retrieving the implanted filter from the patient's vein, comprising: removing the enclosed filter from the vein. 9. Folding the plurality of flexible anchor members comprises: a. Advancing the actuator until it contacts a predetermined portion of each of the plurality of flexible anchor members; b. Distributing pressure to the plurality of flexible anchor members by applying pressure to the actuator, removing the anchor members from the inner wall of the vein, and bending the anchor members sufficiently toward themselves toward the plurality of shaped filter elements. And allowing the outer shield to pass over the plurality of folded flexible anchor members. 10. The step of retracting the filter into an outer shield, comprising: a. Contacting a plurality of shaped filter elements with an outer shield; b. Holding the outer shield in place; c. The plurality of shaped filter elements are disengaged from contact with the vein inner wall and a force is applied to the filter elements to cause them to bend so that the outer shield passes over the filter elements and retracts the filter into the outer shield. And retracting the fixing device.
The method described in. 11. The step of folding the plurality of flexible anchor members comprises: a. Advancing the actuator in contact with the joining member while holding the fixation device in place; b. Distributing the pressure to release the plurality of flexible anchor members from the bonding member by applying pressure to the actuator and the bonding member, removing the anchor member from the inner wall of the vein, and substantially aligning the anchor member 9. A method according to claim 8 including the steps of: folding the outer shield substantially longitudinally with respect to the direction of removal and positioning the outer shield sufficiently close to allow passage over the anchor member. 12. The step of retracting said filter into an outer shield, comprising: a. Contacting a plurality of shaped filter elements with an outer shield; b. Holding the outer shield in place; c. Removing the plurality of shaped filter elements from contact with the intravenous wall and retracting the fixation device in a manner to apply a force to the filter elements to bend, wherein the bending method comprises: Each of which is disposed longitudinally, such that the outer shield passes over the filter element such that the filter is drawn into the outer shield. 13. A. A filter portion having a plurality of shaped filter elements, each of the plurality of shaped filter elements having a mating end and a vein wall engaging end; b. A locating portion having a plurality of shaped flexible anchor members, wherein each of the plurality of shaped flexible anchor members is configured to impede movement in a first direction with a mounting end. A locating portion having a retaining end engaging the vein lining; c. A joining member interposed between the filter portion and the positioning portion, the joining member having a first end coupled to the joining end of the plurality of shaped filter elements;
A joining member having a connecting portion; and d. A mounting member retained by the connecting portion, the mounting member connecting to a mounting end of each of the plurality of molded flexible anchor members; e. An improved retrievable thrombosis filter including a fixation device coupled to the attachment member, wherein the plurality of shaped flexible anchor members are adapted to have a plurality of shaped flexible anchor members when pressure is applied to the fixation device. An improved retrievable thrombosis filter that can be folded from holding contact with and encapsulate the thrombosis filter for removal. 14. The filter of claim 13, wherein the connecting portion has a longitudinal cavity, and wherein the mounting member is slidably retained within the longitudinal cavity. 15. The fixation device comprising: a. A mandrel having a first end adhered to said first end of said joining member, said mandrel passing through said mounting member for a second end;
A mandrel having an end of b. And a hook element connected to the second end of the mandrel. 16. The fixation device comprising: a. An elongate tube disposed coaxially with the mandrel, the elongate tube having a first end bonded to the mounting member and a second end; b. A pressure member attached to the second end of the elongate tube; and applying pressure to the pressure member while holding the hook element. 16. The filter of claim 15, wherein a member is slid into the elongated cavity and the connecting portion folds the plurality of shaped flexible anchor members into a substantially parallel arrangement. 17. A method according to claim 17, wherein each of said plurality of molded flexible anchor members is coupled to said retaining end and is provided with a predetermined first.
14. A first portion having a first cross-section and a second portion having a predetermined second cross-section connected to the holding end and having a smaller area than the predetermined first cross-section. Filter. 18. The filter of claim 17, wherein each of said plurality of shaped flexible anchor members is formed from a class of resilient materials including Nitinol, stainless steel, platinum, tungsten, and chromium alloys. . 19. The filter of claim 18, wherein each of the plurality of shaped flexible anchor members is formed from a superelastic ribbon wire. 20. The holding end of each of the plurality of shaped flexible anchor members is greater than the flexibility of a corresponding one of the plurality of shaped flexible anchor members. A curved flat portion to achieve a large predetermined desired flexibility, said curved flat portion having a length sufficient to engage the corresponding vein wall without penetrating the vein wall; 18. The filter according to claim 17, including a protrusion extending outward. 21. Each of the plurality of shaped filter elements comprises: a. A snake-shaped portion having a first cross-sectional area, a first end formed at the joining end, and a lower end; b. A lower member having a second cross-sectional area smaller than the first cross-sectional area, an upper end coupled to the lower end of the snake-shaped portion, and a bottom end; c. A curved flat portion for achieving a predetermined desired flexibility, connected to the bottom end and having a length sufficient to engage the corresponding vein wall without penetrating the vein wall 14. A filter as claimed in claim 13 including a curved flat portion including a protrusion extending outward. 22. Each of the plurality of shaped filter elements comprises: a. A helically shaped portion having a first end coupled to the joining member and a second end; b. A lower member having a third end coupled to the second end of the helically shaped portion and a fourth end; c. A curved flat portion for achieving a predetermined desired flexibility, connected to said fourth end and having a length sufficient to engage the corresponding vein wall without penetrating the vein wall; 14. A filter as claimed in claim 13, comprising a curved flat portion comprising an outwardly extending projection having 23. The filter of claim 13, wherein said first end of said joining member is formed as a frustum to minimize turbulence of blood passing thereover. 24. The method according to claim 24, wherein the coupling portion includes a longitudinal cavity having a leading end and a trailing end, and wherein the mounting member is secured within the longitudinal cavity proximate the first end of the joining member. The vertical cavity is closed at the rear end and a plug member is adhered to the distal end of the vertical cavity.
3. The filter according to 3. 25. The mounting end of each of the plurality of molded flexible anchor members passes through the plug member, the securing device includes a mandrel passing through the plug member;
The mandrel has a first end bonded to the mounting member, and a second end.
25. The filter of claim 24, wherein a hook device is connected to the second end of the mandrel. 26. a. Thrombosis filter means for filtering and retaining thrombotic material that travels in a second direction when deployed in a first direction; b. Retaining means for retaining on a corresponding lumen inner wall and for restricting movement in said second direction; c. Joining means for joining the thrombosis filter means and the holding means; d. An improved retrievable filter comprising: said retaining means and retraction means for retracting said thrombotic filter means in response to externally applied pressure for removal in said second direction. 27. The thrombosis filter means is disposed about a longitudinal axis and includes a plurality of shaped thrombosis filter means, the filter means being diverted outwardly about the longitudinal axis. 27. The filter of claim 26, wherein the filter extends substantially in a first direction and is arranged to retain thrombus material traveling in a second direction. 28. The holding means comprising: a. A plurality of positioning means, each of which is coupled to the plurality of shaped thrombosis filter means.
A plurality of locating means having diverging means about said longitudinal axis, extending substantially in said second direction, and having a second end; b. A plurality of engagement means, each of which engages with the second end of a corresponding one of the plurality of positioning means to limit movement in the second direction. 28. The filter of claim 27, comprising a plurality of said engaging means arranged to engage a corresponding lumen inner wall. 29. The filter according to claim 28, wherein said retracting means includes folding means for folding said plurality of positioning means in said second direction. 30. a. Holding means for securely holding said plurality of positioning means in the longitudinal direction; b. 30. The filter of claim 29, further comprising propulsion means for directing the plurality of engagement means in the second direction and forcing the plurality of positioning means into a substantially parallel arrangement. 31. The plurality of positioning means and the plurality of thrombosis means for removing the plurality of positioning means and the plurality of shaped thrombosis filter means in the second direction. 31. The filter of claim 30, further comprising surrounding means surrounding the filter means. 32. The filter according to claim 28, wherein said retracting means includes flexing means for flexing said plurality of positioning means in said first direction. 33. The retraction means comprising: a. Holding means for securely holding said plurality of positioning means in the longitudinal direction; b. 33. The filter according to claim 32, further comprising: folding means for directing the plurality of engaging means in the first direction to arrange the plurality of positioning means in a substantially parallel arrangement. 34. The retraction means includes: the plurality of positioning means and the plurality of thrombosis filter means for removing the plurality of positioning means and the plurality of thrombosis filter means in the second direction. 34. The filter of claim 33, further comprising surrounding means. 35. a. A filter array; b. A plurality of anchor struts having a proximal end and a distal end, the struts being connected to a filter array near the proximal end, the distal end of the struts comprising a butt portion and a sharp projecting portion, A strut including a region in which the abutment portion extends distally beyond the sharp projection and the abutment portion includes an area of increased flexibility toward the end. 36. The recoverable filter of claim 35, wherein the area of increased flexibility is located at an end of the sharp projection. 37. The recoverable filter of claim 35, wherein the abutment portion has a thickness that decreases toward the distal end in a region where the flexibility decreases toward the distal end. 38. At least a portion of the strut between the proximal and distal ends of the strut is ribbon-shaped and has a width and thickness such that its thickness is less than the width. 4. The recoverable filter according to claim 1. 39. The recoverable filter of claim 35, wherein the length of the sharp protrusion is about 2 to 6 millimeters. 40. The recoverable filter of claim 35, wherein the length of the patch is about 4 to 20 millimeters. 41. The recoverable filter of claim 40, wherein the length of the abutment is about 10 to 20 millimeters. 42. A first direction and a second direction opposite to the first direction.
A vascular filter having an axis extending in the direction of: a plurality of struts, each of the struts having a first end connected at a hub, and a second end. A plurality of struts extending in a first direction from the hub and generally diverging from the axis toward the second end, and coupled to the filter, in a first direction relative to the hub; A vascular filter comprising a removable mooring connection disposed. 43. The vascular filter according to claim 42, wherein the mooring connection connects to a hub. 44. The vascular filter according to claim 42, wherein said mooring connection connects means for folding a strut toward said axis. 45. The mooring connection connects to a retraction member positioned to engage a strut, thereby moving the strut from the first position to a second folded position near an axis. 43. The vascular filter according to claim 42, which is capable of performing. 46. The retraction member includes a plurality of loops, each loop extending in a second direction, each loop tying at least one strut such that the mooring connection is moved in a first direction. And wherein the loop moves from the first position of the loop to a second position of the loop while engaging the support and moving the support from the first position to a second position near the axis. 45. The vascular filter according to 45. 47. The vascular filter according to claim 42, wherein the mooring connection comprises a hook. 48. The vascular filter according to claim 42, wherein said second end is sharpened to penetrate a vessel wall. 49. The barge at the second end.
A blood vessel filter according to claim 1. 50. The vascular filter according to claim 42, further comprising an elongated connector for connecting the mooring connector and a hub. 51. The elongate coupler expands and contracts.
The blood vessel filter according to 0. 52. A first direction and a second direction opposite to the first direction.
Providing a filter having an axis extending in the direction of, wherein each of the plurality of struts comprises a first end and a second end, wherein the first end is connected at a hub. ,
The post is disposed at a first position extending generally from the hub in a first direction and diverging from the axis generally toward a second end, and a removable mooring connection is connected to the filter and is connected to the filter in a first position. A step of connecting the removal mooring part to the mooring connection part; a step of folding the strut to a second position near the axis; and a step of drawing the filter into a catheter disposed in the blood vessel. A method for removing a blood vessel filter from a blood vessel, comprising: