Intravascular safety cage

Abstract

An endovascular treatment device (10) comprises: an endovascular catheter (12); a spiral cage (14) configured to be rotated by the endovascular catheter into a vascular occlusion located in a blood vessel of an associated patient; and a treatment device (16) configured to be moved to a position inside the spiral cage when the spiral cage is rotated into the vascular occlusion, and further configured to be operated to treat the vascular occlusion when positioned inside the spiral cage.

Description

Technical Field

[0001] The following generally relates to the fields of catheterization, vascular treatment, lesion management, and related fields. Background Art

[0002] Treatment of intravascular blockages generally becomes more difficult as the age of the blockage increases. As the blockage becomes more chronic, it generally becomes larger, more rigid, and more strongly adhered to the affected vasculature. As these blockages become more chronic, the effectiveness of standard atherectomy and thrombectomy tools decreases.

[0003] In developing new tools for treating these chronic conditions, increasing the aggressiveness of the tool (sharpness of contact features, force of contact, speed of movement) provides improved efficacy. However, there is a need to limit the aggressiveness of the tool to prevent damage to the vessel being treated. Maintaining the safety of the device often results in making it less aggressive to the point where it is no longer effective.

[0004] Certain improvements are disclosed below to overcome these and other problems. Summary of the invention

[0005] In some embodiments disclosed herein, an intravascular treatment device includes: an intravascular catheter; a spiral cage configured to be rotated by the intravascular catheter into a vascular obstruction located in a blood vessel of an associated patient; and a treatment device configured to be moved to a position inside the spiral cage when the spiral cage is rotated into the vascular obstruction, and further configured to be operated to treat the vascular obstruction when positioned inside the spiral cage.

[0006] In some embodiments disclosed herein, a vascular treatment method includes: inserting a spiral cage into a blood vessel of an associated patient at a blood blockage located in the blood vessel, and screwing the spiral cage into the blood vessel blockage located within the blood vessel; inserting a treatment device into the interior of the spiral cage after screwing the cage into the blood vessel blockage; operating the treatment device while inserted into the interior of the spiral cage to apply treatment to treat the blood vessel blockage; removing the treatment device from the spiral cage; and removing the spiral cage from the blood vessel.

[0007] In some embodiments disclosed herein, a vascular treatment system includes: a treatment device; and a helical cage configured to be rotated into a vascular occlusion located in a blood vessel of an associated patient, the cage having a diameter smaller than the diameter of the blood vessel and sized to accommodate the treatment device.

[0008] One advantage resides in providing a safety barrier between the vessel wall and the therapeutic treatment tool.

[0009] Another advantage resides in preventing trauma to the vessel wall.

[0010] Another advantage resides in enabling the use of a wider range of treatment tools for treating clots in blood vessels by using a safety barrier between the treatment tool and the vessel wall.

[0011] Another advantage resides in providing a removable safety barrier between the vessel wall and the therapeutic treatment tool.

[0012] A given embodiment may provide none, one, two, more, or all of the aforementioned advantages, and / or may provide other advantages as will become apparent to one of ordinary skill in the art upon reading and understanding the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The disclosure may take the form of various components and arrangements of components, and may take the form of various steps and arrangements of steps. The drawings are only for the purpose of illustrating the preferred embodiments and are not to be construed as representations of the disclosure.

[0014] Figure 1 A vascular treatment device according to the present disclosure is diagrammatically illustrated.

[0015] Figure 2 Diagrammatically illustrates Figure 1 Side view of the spiral safety cage of the device.

[0016] Figure 3 Diagrammatically illustrates the view from a point of view close to the central axis of the spiral Figure 1 and 2 Perspective view of a spiral safety cage.

[0017] Figure 4 Diagrammatically illustrates the use of Figure 1 A device for performing a method of vascular treatment. DETAILED DESCRIPTION

[0018] In intravascular clot removal (debulking) procedures, a removal tool such as a mechanical cutter or a laser catheter that performs laser ablation is used to remove clot material. In such procedures, a significant concern is the possibility that the mechanical cutter or laser ablation may cut into the vessel wall, causing weakening or even rupture of the vessel wall.

[0019] A spiral intravascular safety cage is disclosed below that is designed to be rotated into a treatment site. The diameter of the safety cage is selected to be slightly smaller than the diameter of the internal vessel lumen so that when screwed into the treatment site, the clot material is mostly inside the spiral safety cage and the wall of the vessel lumen is outside the safety cage. After the spiral safety cage is so placed, a removal tool is introduced and operated to remove the clot material inside the safety cage, while the vessel wall is safely located outside the safety cage. In the case of laser ablation, the working distance of the laser is typically on the order of tens of microns, so that the spiral safety cage provides sufficient protection for the vessel wall.

[0020] For example, the spiral safety cage is suitably made of stainless steel, nitinol, or a shape memory polymer. In the latter two cases, the nitinol or shape memory polymer is set into a designed spiral shape and can then collapse to be stored in the lumen of the delivery catheter and expand to its set size when deployed. After the spiral safety cage is deployed at the treatment site, the same or a different catheter can be used to deliver the removal tool to the treatment site. After the treatment is completed, the spiral safety cage is removed by rotating it in a rotational direction opposite to the rotational direction used in deployment and then pulling it back into the lumen of the catheter.

[0021] refer to Figure 1 , schematically shows an illustrative vascular treatment device 10. Figure 1 As shown, the vascular treatment device 10 can be inserted into a blood vessel for treating a lesion (or clot, or blockage, etc.) in the blood vessel. The vascular treatment device 10 includes, for example, an intravascular catheter 12 and a spiral safety cage 14, which is located at the distal end 13 of the intravascular catheter 12 and is configured to be rotated by the intravascular catheter 12 into the vascular blockage located in the blood vessel. It should be noted that Figure 1 The intravascular catheter 12 is not drawn to scale, and can have a length suitable for inserting the catheter 12 into a blood vessel to deliver the distal end 13 along a (possibly tortuous) path through the vasculature to a treatment site, wherein the length of the catheter 12 is sufficient such that the rotational control 18 remains external to the patient when the distal end 13 reaches the treatment site.

[0022] Treatment equipment 16 (in Figure 1The treatment device 16 (schematically shown as a cylinder) is configured to be moved to a position inside the spiral safety cage 14 when the spiral safety cage 14 is rotated into a vascular occlusion, and is also configured to be operated to treat the vascular occlusion when positioned inside the spiral cage 14. The treatment device 16 is configured to move the treatment device 16 to a position inside the spiral cage 14 and operate the treatment device 16 to treat the vascular occlusion when the spiral cage 14 is rotated into the vascular occlusion using the same intravascular catheter 12 that is used to rotate the spiral cage 14 into the vascular occlusion. In one embodiment, the treatment device 16 includes an obstruction removal tool that is configured to fit within the spiral cage 14 to remove the vascular occlusion. In another embodiment, the treatment device 16 includes a laser ablation catheter that is configured to fit within the spiral cage 14 to provide ablation treatment to the vascular occlusion.

[0023] A rotation controller 18 is located at the proximal end 15 of the intravascular catheter 12. The rotation controller 18 is operably connected to rotate the spiral cage 14. The rotation controller 18 can be rotated manually by a user, or can be motorized using a motor (not shown). Figure 1 As shown, the second intravascular catheter 20 is located within the intravascular catheter 12, and the intravascular catheter 12 coaxially surrounds the second intravascular catheter 20. The rotation controller 18 is operatively connected to rotate the helical cage 14 through the second intravascular catheter 20. To this end, the second intravascular catheter 20 is configured to move the treatment device 16 to a position inside the helical cage 14 when the helical cage 14 is rotated into the vascular occlusion and operate the treatment device 16 to treat the vascular occlusion.

[0024] It should be noted that the illustrative catheter 12 may have Figure 1 , such as a guidewire lumen extending along the entire length of the catheter 12 for over the wire (OTW) delivery along a guidewire that is pre-inserted into the vessel along the path to the treatment site, or a shorter guidewire lumen with an exit port in a rapid exchange (RX) catheter design. By way of further illustration, other contemplated variations include the addition of an ultrasound transducer at or near the distal end 13 for imaging the treatment site, the addition of one or more radiopaque markers on the catheter 12 to enable visualization by a suitable interventional imaging modality, etc. In some embodiments, the proximal end can be connected to a vacuum pump (not shown) to apply vacuum aspiration via the lumen of the sheath 22 or second intravascular catheter 20 to remove clot material excised by the treatment device 16.

[0025] Figure 1An embodiment is depicted in which the catheter 12 is an outer sheath that delivers a spiral cage 14, and the treatment device 16 is mounted on an inner intravascular catheter 20 located within a lumen extending through the outer sheath catheter 12. This design has substantial advantages. The sheath catheter 12 can be rotated by a handle or other rotation control 18 to rotate the spiral cage 14 into position to protect the inner wall of the vessel. Thereafter, both the spiral cage 14 and the outer sheath catheter 12 can remain in position, wherein the spiral cage 14 remains attached to the distal end 13 of the outer sheath catheter 12 to provide an inner lining path through the vascular system, within which the treatment device 16 can be operated via the inner intravascular catheter 20.

[0026] However, in other embodiments (not shown), it is contemplated that these operations are performed using completely separate and unrelated catheters. For example, a first catheter may be used to deliver the spiral cage 14, and then the first catheter is withdrawn from the vasculature, and a second catheter is inserted into the vasculature to deliver the treatment device 16, and then withdrawn and the first catheter reinserted to retrieve the spiral safety cage 14. In such embodiments, the first catheter appropriately includes a mechanically or electrically actuated clamp or the like that operates as a release / pick-up mechanism. Using this mechanism, the spiral safety cage 14 is released after it is in place in the clot, so that the first catheter can be removed while leaving the spiral safety cage 14 in place; and during a subsequent retrieval step, the release / pick-up mechanism recaptures the spiral safety cage 14 to retrieve it.

[0027] refer to Figure 2 and Figure 3 , with a side view ( Figure 2 ) and a perspective view from a point close to the central axis of the spiral ( Figure 3 ) shows the spiral cage 14. The spiral cage 14 has Figure 2 and 3 The diameter D indicated in H , which is preferably slightly smaller than the diameter of the blood vessel at the treatment site. Figure 2 and 3 The corresponding radius R indicated in H , where R H =0.5×D H The spiral cage 14 is screwed into the clot material and is thus held in place by the clot material close to the inner vessel wall. If the vessel has a diameter D BV and the corresponding blood vessel radius R BV =0.5×D BV , then it corresponds to the radius R H With R BV The outermost portion of the clot between the annuli will be located outside the helical cage 14 and will therefore not be removed by the treatment tool 16 operating within the helical cage 14. HThe choice of D is appropriately selected based on the desired diameter of the core of clot material desired to be excised (which is equal to D H , ignoring the thickness of the stainless steel or other wire forming the spiral cage 14) and the clotted material at radius R H With R BV For therapeutic purposes, a typical design consideration is that the open lumen created by the treatment should have a residual annulus of approximately D H diameter, so this should be large enough to support the desired blood flow.

[0028] The spiral cage 14 also has only Figure 2 The thread pitch P is marked in the side view of H It should be noted that Figure 2 and 3 is schematic and, in particular, diagrammatically shows the pitch P H . Usually, the pitch P H The size of the gap between adjacent turns of the helical coil 14 is determined together with the wire diameter of the stainless steel or other wire that is helically wound to form the helical cage 14. Neglecting the finite wire diameter, the gap is therefore equal to the pitch P H This gap is the space through which the treatment device 16 can in principle be operatively passed in order to undesirably cut into the inner wall of the blood vessel. Therefore, in order to avoid such undesirable cutting into the blood vessel wall, the pitch P H should be chosen to be small enough that (together with the actual wire diameter) the resulting gap is too small for the treatment device 16 to operatively penetrate. An appropriate pitch P may be selected based on the properties of the treatment device 16. H For example, where the treatment device 16 is a laser ablation catheter, the physical dimensions of the tip of the laser catheter will be at the pitch P H Below a certain maximum permissible value, the cutting laser hole is prevented from passing through the gap between adjacent turns of the helical coil 14 and ablating the inner vessel wall. In this regard, it is again noted that the working distance of the laser of a typical laser ablation laser hole is generally on the order of tens of microns. Similarly, if the treatment device 16 is a removal tool that employs a rotary or other type of cutter, the size of the cutter and its mounting to the distal tip of the inner catheter 20 will be at a certain maximum permissible value. H Conditions below a certain maximum allowed value prevent the cutter from passing through the gaps between adjacent turns of the helical coil 14 and cutting into the inner vessel wall.

[0029] The helical cage 14 may include, for example, stainless steel, nitinol, or a shape memory polymer. The helical cage 14 includes a plurality of turns 24 that form the helical cage 14. With particular reference to Figure 3As shown in the proximal perspective view of the spiral cage 14, the spiral cage 14 optionally has a distal end 26 that is turned inwardly toward the axis of the spiral cage 14. When the spiral cage 14 is screwed into the clot, the inwardly turned end 26 is the leading end, and the inwardly turned end 26 reduces the possibility of the end being misdirected and embedded in the vessel wall.

[0030] refer to Figure 4 , an illustrative embodiment of an intravascular treatment method 100 using the intravascular treatment device 10 is diagrammatically shown as a flow chart. At operation 102, the intravascular catheter 12 is inserted into the blood vessel to position the spiral cage 14 proximate to the clot in the blood vessel. At operation 104, the spiral cage 14 is then screwed into the blood vessel obstruction. At operation 106, the treatment device 16 is inserted into the interior of the spiral cage 14. At operation 108, the treatment device 16 is operated while the treatment device 16 is inserted into the interior of the spiral cage 14 to apply treatment (e.g., using an obstruction removal tool, a laser ablation catheter, etc.). Once the treatment is completed, at operation 110, the treatment device 16 is removed from the spiral cage 14. At operation 112, the spiral cage 14 is removed from the blood vessel. At operation 114, the intravascular catheter 12 is withdrawn from the blood vessel. As previously described, using Figure 1 With the device, operations 106 , 108 , and 110 may be performed with the outer sheath catheter 12 remaining in place and attached to the deployed helical safety cage 14 , such that the only additional steps performed by a human operator to use the helical safety cage 14 are additional steps 104 and 112 .

[0031] The spiral cage 14 should have sufficient density and thickness so that it prevents the treatment device 16 from contacting the vessel wall. For example, the wire diameter of the surgical stainless steel or other metal, ceramic or polymer that constitutes the spiral safety cage 14 can be selected to provide a sufficient safety barrier with sufficient rigidity to allow the spiral safety cage 14 to be screwed into the clot. The spiral cage 14 must also be durable so that contact with the treatment device 16 activated inside it does not cause damage. However, it should be noted that the spiral cage can be manufactured at low cost and is therefore a consumable component used only for a single intravascular treatment in some embodiments. Therefore, it only needs to be durable enough for a single treatment session. Alternatively, if the spiral cage 14 is made of surgical stainless steel or another durable material that can also be autoclaved, it can be sterilized and reused between procedures.

[0032] like Figure 3As shown, one embodiment of the spiral cage 14 includes a guide edge 26 that is angled inwardly toward the center of the blood vessel to reduce the possibility of perforation when the spiral cage 14 is inserted. The spiral cage 14 can collapse downward inside the intravascular catheter 12, or adopt a shape memory action so that it will fit through a smaller entry size and is easy to navigate through the blood vessel. Once the tip of the intravascular catheter 12 reaches the treatment site, the spiral cage 14 can be twisted out of the intravascular catheter 12 so that it expands to the desired size and penetrates between the obstruction and the blood vessel wall. Once the spiral cage 14 is screwed into place, the treatment device 16 can be operated inside the spiral cage 14, wherein the risk of the treatment device 16 damaging the blood vessel wall is mitigated. Once the treatment is completed, the spiral cage 14 can be rotated in the opposite direction to extract / remove it from the blood vessel and return it to its collapsed state inside the intravascular catheter 12 to be removed from the body.

[0033] The present disclosure has been described with reference to the preferred embodiments. Modifications and alterations may occur to others upon reading and understanding the foregoing detailed description. The exemplary embodiments are intended to be interpreted as including all such modifications and alterations as long as they fall within the scope of the appended claims or their equivalents.

Claims

1. An intravascular treatment device (10), comprising: Intravascular catheters (12); a spiral cage (14) configured to be rotated by the intravascular catheter into a vascular occlusion located in a blood vessel of an associated patient; and A treatment device (16) is configured to be moved to a position inside the helical cage when the helical cage is rotated into the vascular obstruction and is further configured to be operated to treat the vascular obstruction when positioned inside the helical cage.

2. The intravascular treatment device (10) according to claim 1, wherein: The treatment device (16) is configured to move the treatment device to the position inside the spiral cage while rotating the spiral cage (14) into the vascular obstruction using the same intravascular catheter (12) used to rotate the spiral cage into the vascular obstruction, and to operate the treatment device to treat the vascular obstruction.

3. The intravascular treatment device (10) according to claim 1, further comprising: a second intravascular catheter (20) different from the intravascular catheter (12); Wherein, the second intravascular catheter is configured to: move the treatment device (16) to the position inside the spiral cage when the spiral cage (14) is rotated into the vascular obstruction, and operate the treatment device to treat the vascular obstruction.

4. The intravascular treatment device (10) according to any one of claims 1 to 3, wherein: The handling device (16) is sized to fit within the diameter of the spiral cage (14).

5. The intravascular treatment device (10) according to any one of claims 1 to 4, wherein: The spiral cage (14) comprises stainless steel.

6. The intravascular treatment device (10) according to any one of claims 1 to 4, wherein: The helical cage (14) comprises Nitinol.

7. The intravascular treatment device (10) according to any one of claims 1 to 4, wherein: The helical cage (14) comprises a shape memory polymer.

8. The intravascular treatment device (10) according to any one of claims 1 to 7, wherein: The treatment device (16) comprises: An obstruction removal tool is configured to fit within the spiral cage (14) to remove the blood vessel obstruction.

9. The intravascular treatment device (10) according to any one of claims 1 to 7, wherein: The treatment device (16) comprises: A laser ablation catheter is configured to fit within the helical cage (14) to provide ablative treatment to the vascular occlusion.

10. The intravascular treatment device (10) according to any one of claims 1 to 9, wherein: The spiral cage (14) has a distal end (26) turned inwardly toward the axis of the spiral cage.

11. A method for treating a blood vessel (100), comprising: inserting a spiral cage (14) into a blood vessel of an associated patient at a vascular obstruction in the blood vessel and screwing the spiral cage into the vascular obstruction in the blood vessel; After the cage is screwed into the vascular occlusion, a treatment device (16) is inserted into the interior of the spiral cage; operating the treatment device to apply therapy to treat the vascular occlusion while the treatment device is inserted into the interior of the helical cage; removing the handling device from the spiral cage; and The helical cage is removed from the blood vessel.

12. The vascular treatment method (100) according to claim 11, wherein: Treatments applied include: The treatment is applied using the treatment device (16) comprising an obstruction removal tool.

13. The vascular treatment method (100) according to claim 11, wherein: Treatments applied include: The therapy is applied using the treatment device (16) comprising a laser ablation catheter.

14. A vascular treatment system (10), comprising: disposal equipment (16); and A helical cage (14) is configured to be rotated into a vascular occlusion located in a blood vessel of an associated patient, the cage having a diameter less than the diameter of the blood vessel and sized to accommodate the treatment device.

15. The intravascular treatment device (10) according to claim 14, wherein: The spiral cage (14) has a distal end (26) turned inwardly toward the axis of the spiral cage.

16. The intravascular treatment device (10) according to any one of claims 14 and 15, wherein: The treatment device (16) comprises one of the following: an obstruction removal tool configured to fit within the spiral cage (14) to remove the blood vessel obstruction; or A laser ablation catheter is configured to fit within the helical cage (14) to provide ablative treatment to the vascular occlusion.

17. The intravascular treatment device (10) according to any one of claims 14 to 16, wherein: The helical cage (14) comprises one of the following: stainless steel, nitinol or a shape memory polymer.

18. The intravascular treatment device (10) according to any one of claims 14 to 17, further comprising an intravascular catheter (12); in, The helical cage (14) is configured to be rotated by the intravascular catheter into a vascular occlusion located in a blood vessel of an associated patient; and The treatment device (16) is configured to be moved to a position inside the spiral cage when the spiral cage is rotated into the vascular obstruction, and is further configured to be operated to treat the vascular obstruction when positioned inside the spiral cage.

19. The intravascular treatment device (10) according to claim 18, wherein: The treatment device (16) is configured to move the treatment device to the position inside the spiral cage while rotating the spiral cage (14) into the vascular obstruction using the same intravascular catheter (12) used to rotate the spiral cage into the vascular obstruction, and to operate the treatment device to treat the vascular obstruction.

20. The intravascular treatment device (10) according to claim 18, further comprising: a second intravascular catheter (20) different from the intravascular catheter (12); Wherein, the second intravascular catheter is configured to: move the treatment device (16) to the position inside the spiral cage when the spiral cage (14) is rotated into the vascular obstruction, and operate the treatment device to treat the vascular obstruction.

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