Novel balloon catheter and method for expanding occluded section of blood vessel

Abstract

According to the novel balloon catheter and the method for expanding the blood vessel blocked segment, balloons comprise the first balloon and the second balloon, the cross section of each balloon is in a gourd shape defined by two semi-circular rings, the first balloon is provided with a guide wire cavity, the balloon is a filling cavity except the guide wire cavity, and the second balloon is used for expanding the blood vessel wall outwards in the blood vessel blocked segment; a balloon filling cavity is formed between the inner tube and the outer tube, a filling cavity of the balloon is communicated with the balloon filling cavity, and an inner cavity of the inner tube is communicated with a guide wire cavity of the balloon. After the covered stent is implanted into a blood vessel occlusion section, the balloon is pushed into the covered stent, the second balloon faces the blood vessel wall side, and the filling material is injected into the balloon after the second balloon is in place. The second balloon can be ejected out from the covered stent to the outer side of the blood vessel wall, so that the outer membrane of the blood vessel and part of the outer-side intima of the blood vessel are broken, the covered stent obtains a space to bulge out of the blood vessel, the diameter of the implanted covered stent is increased, and then the balloon is withdrawn, so that blood flow can smoothly flow through the covered stent, and the interior of the covered stent is prevented from being blocked after an operation.

Description

Technical Field

[0001] The invention belongs to the technical field of balloon catheters, and in particular relates to a novel balloon catheter and a method for dilating an occluded segment of a blood vessel. Background Art

[0002] For vascular obstructive diseases, such as coronary artery atherosclerosis (CHD), cerebrovascular disease (such as cerebral artery stenosis), peripheral arterial disease (such as lower limb artery stenosis), etc., arterial bypass surgery can be performed, or percutaneous transluminal angioplasty (PTA) or covered stent implantation can be used to bypass or expand the arterial occlusion caused by atherosclerosis and restore distal blood perfusion.

[0003] However, both methods have certain disadvantages. For example, when performing arterial bypass surgery, patients with longer vascular occlusion segments will have longer surgical incisions, which will cause greater surgical trauma to the patients, and there will still be proliferation at both ends of the transplanted blood vessels and the arterial anastomosis, leading to blockage of the transplanted blood vessels, and then to poor distal perfusion in the later stage. However, the postoperative patency rate of arterial bypass surgery is higher than that of covered stent implantation; during covered stent implantation, although interventional technology is used and the trauma is less, the implanted stent will still cause blockage in the stent in the later stage due to the elastic retraction of the blood vessels and the formation of proliferations, leading to poor distal perfusion in the later stage.

[0004] Therefore, how to overcome the above technical defects is a problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] The purpose of the present invention is to provide a novel balloon catheter and a method for dilating an occluded blood vessel segment, which can improve the patency of blood flow in a stent implanted in the occluded blood vessel segment and prevent postoperative internal blockage of the stent.

[0006] In order to solve the above technical problems, the present invention provides a novel balloon catheter, comprising a balloon, an inner tube and an outer tube;

[0007] The balloon comprises a first balloon and a second balloon which are buckled relative to each other. The cross section of the balloon is a gourd shape surrounded by two semicircular rings. The center of the first balloon has a guidewire cavity for passing a guidewire. The balloon is a filling cavity except the guidewire cavity. The second balloon is used to expand the blood vessel wall outward at the blocked segment of the blood vessel.

[0008] The outer tube is sleeved on the outer side of the inner tube, a balloon filling cavity is formed between the inner tube and the outer tube, the filling cavity of the balloon is communicated with the balloon filling cavity, and the inner cavity of the inner tube is communicated with the guide wire cavity of the balloon.

[0009] Optionally, in the above-mentioned novel balloon catheter, a cutting piece is provided on the second balloon on a side opposite to the first balloon.

[0010] Optionally, in the above-mentioned novel balloon catheter, the cutting element is disposed on the outer wall of the second balloon and arranged along an axial direction parallel to the second balloon.

[0011] Optionally, in the above-mentioned novel balloon catheter, the cutting member is a metal wire.

[0012] Optionally, in the above novel balloon catheter, the cross section of the first balloon is an ellipse with a notch;

[0013] And / or, the cross-section of the second balloon is circular or elliptical with a notch.

[0014] Optionally, in the above-mentioned novel balloon catheter, the eccentricity of the first balloon is greater than the eccentricity of the second balloon.

[0015] Optionally, in the above-mentioned novel balloon catheter, the outer diameter of the first balloon is greater than the outer diameter of the second balloon.

[0016] Optionally, the novel balloon catheter further comprises a handle, and the handle or the distal end of the outer tube is provided with a balloon filling port for communicating with the balloon filling cavity.

[0017] The present invention also provides a method for dilating an occluded segment of a blood vessel, using the novel balloon catheter described in the above embodiment, the method comprising:

[0018] Implant a covered stent in the occluded segment of the blood vessel;

[0019] Pushing a balloon into the stent graft so that the second balloon on the balloon faces the blood vessel wall;

[0020] After reaching the occluded section of the blood vessel, a filling material is injected into the balloon, and the second balloon can be pushed outward from the inside of the stent graft toward the outside of the blood vessel wall, so that the adventitia and part of the outer vascular media rupture, and the stent graft obtains space and bulges out of the blood vessel;

[0021] After the diameter of the implanted stent is increased, the balloon is withdrawn to allow blood to flow smoothly through the stent.

[0022] Optionally, in the above method for dilating an occluded blood vessel segment, the method of implanting a covered stent in the occluded blood vessel segment specifically includes:

[0023] Subintimal angioplasty is performed using a common balloon to bypass the sclerotic plaque in the occluded segment of the blood vessel. Under the combined effect of pressure and elasticity of the sclerotic plaque, the vascular adventitia and part of the outer vascular media in the occluded segment of the blood vessel, the new lumen formed by the subintimal angioplasty has a crescent-shaped cross-section, and the covered stent is then implanted along the guide wire.

[0024] The present invention provides a novel balloon catheter, which has the following beneficial effects:

[0025] When using interventional methods to implant covered stents to treat vascular occlusion diseases, a conventional ordinary balloon is first used for subintimal plasty. When passing through the occluded segment of the blood vessel, the guide wire usually penetrates the vascular intima from the normal position proximal to the affected part and enters the subintimal part, passes through the subintimal part to the normal position distal to the affected part, and then implants the covered stent along the guide wire. After implanting the covered stent, the adventitia and part of the outer middle membrane can be separated by expanding the subintimal space of the blood vessel, creating a certain space for blood flow to pass through, but because the sclerotic plaque in the affected part is relatively dense, the covered stent expands poorly. At this time, a balloon is pushed into the covered stent, and the second balloon is facing the vascular wall side. After it is in place, the filling material is injected into the balloon. The second balloon can push the covered stent outward from the covered stent, that is, the covered stent is expanded with a balloon, so that the adventitia and part of the outer middle membrane rupture, so that the covered stent has space to bulge out of the blood vessel, increasing the diameter of the covered stent after implantation, and then withdrawing the balloon so that blood flow can flow smoothly through the covered stent, improving distal perfusion.

[0026] Through the above setting, the second balloon can push the blood vessel wall at the occluded site to bulge outward or even rupture, allowing the stent graft to gain space to bulge outward from the blood vessel, thereby increasing the diameter of the stent graft after implantation, and ultimately improving the patency of blood flow in the stent graft at the occluded section of the implanted blood vessel, thereby preventing internal blockage of the stent graft after surgery.

[0027] The present invention also provides a method for dilating an occluded segment of a blood vessel, which uses the above-mentioned novel balloon catheter and has the same beneficial effects, which will not be described in detail herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0029] Figure 1 A schematic structural diagram of a novel balloon catheter provided by an embodiment of the present invention;

[0030] Figure 2 for Figure 1 Schematic diagram of the cross section of the mid-sacculus;

[0031] Figure 3 A schematic diagram of a guidewire provided in an embodiment of the present invention passing through an occluded blood vessel and being placed behind a stent graft (the straight line shaded portion is a sclerotic plaque, and the Z-shaped curve portion is a stent graft);

[0032] Figure 4 A schematic diagram of a novel balloon catheter implanted in an occluded blood vessel provided by an embodiment of the present invention in an expanded state (this figure shows a filling material being injected into the balloon, and the balloon is only a schematic diagram, and the inner tube and outer tube structures are not shown);

[0033] Figure 5 For Figure 4 A schematic diagram of the affected area after the novel balloon catheter of the occluded blood vessel segment provided by an embodiment of the present invention is withdrawn after the state (the effect diagram after the treatment of the occluded blood vessel segment).

[0034] exist Figure 3-Figure 5 Middle: Red is the vascular adventitia, purple is the vascular media, and blue is the vascular intima.

[0035] exist Figure 1-Figure 5 middle:

[0036] 110-balloon; 120-inner tube; 130-outer tube; 131-balloon filling port; 140-cutting piece;

[0037] 200-guidewire;

[0038] 300-Stent Graft;

[0039] 400-Vascular occlusion segment. DETAILED DESCRIPTION

[0040] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0041] In the description of this application, it should be understood that the terms "proximal end" and "distal end" used throughout the text refer to near and far relative to the operator. When the present invention is used, the end close to the doctor or operator is the "proximal end", that is, the end where the operator is located, and the end away from the doctor or operator is the "distal end", that is, the end where the balloon is located. The above-mentioned description of the orientation is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0042] The core of the present invention is to provide a novel balloon catheter and a method for dilating an occluded segment of a blood vessel, which can improve the patency of blood flow in a stent implanted in the occluded segment of a blood vessel and prevent postoperative internal blockage of the stent.

[0043] In order to enable those skilled in the art to better understand the technical solution provided by the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0044] Specifically, please refer to Figure 1-Figure 5 The present invention provides a novel balloon catheter, which includes a balloon 110, an inner tube 120 and an outer tube 130.

[0045] The balloon 110 includes a first balloon and a second balloon which are relatively buckled. The cross section of the balloon 110 is a gourd shape surrounded by two semicircular rings. The center of the first balloon has a guidewire cavity for passing the guidewire 200. The balloon 110 is a filling cavity except the guidewire cavity. The second balloon is used to expand the blood vessel wall outward in the blocked section of the blood vessel.

[0046] The outer tube 130 is sleeved on the outside of the inner tube 120, the distal end of the balloon 110 is connected to the distal end of the inner tube 120, the proximal end of the balloon 110 is connected to the distal end of the outer tube 130, the proximal end of the outer tube 130 and the proximal end of the inner tube 120 are both connected to the handle, a balloon filling cavity is formed between the inner tube 120 and the outer tube 130, the filling cavity of the balloon 110 is connected to the balloon filling cavity, and the inner cavity of the inner tube 120 is connected to the guide wire cavity of the balloon.

[0047] It should be noted that the blood vessel wall is usually divided into three layers: 1. The intima, which is the innermost layer of the blood vessel wall, is adjacent to the blood vessel cavity and is the thinnest layer of the blood vessel wall. 2. The middle membrane, located between the intima and the adventitia, is responsible for maintaining the elasticity and stability of the blood vessel wall and is involved in regulating the contraction and relaxation of the blood vessels. 3. The adventitia, which is the outermost layer of the blood vessel wall, provides additional support and protection for the blood vessels.

[0048] The "subintimal" referred to in this scheme refers to being located below the intima, that is, between the intima and the media.

[0049] This solution provides a novel balloon catheter, and its use method is as follows: when using interventional methods to perform covered stent implantation to treat vascular occlusion diseases, first use a conventional ordinary balloon to perform subintimal plasty. When passing through the vascular occlusion segment 400, the guide wire 200 usually penetrates the vascular intima from the normal position proximal to the affected part and enters the subintimal part (i.e., between the vascular intima and the vascular media), passes through the subintimal part to reach the normal position distal to the affected part and then implants the covered stent 300 along the guide wire 200. After implanting the covered stent 300, the subintimal space of the blood vessel can be expanded to separate the vascular adventitia and part of the outer media, creating a certain space for blood flow to pass through. However, since the sclerotic plaques in the affected part are relatively dense, the covered stent 300 is poorly expanded (e.g., Figure 3 At this time, the balloon 110 is pushed into the stent graft 300, and the second balloon is directed toward the vascular wall. After the balloon 110 is in place, the filling material is injected into the balloon 110. The second balloon can push the stent graft 300 out of the vascular wall from the inside of the stent graft 300, that is, the stent graft 300 is expanded by the balloon 110 (as shown in FIG. Figure 4 As shown in FIG. 1 ), the adventitia and part of the outer middle membrane of the blood vessel are ruptured, so that the coated stent 300 has space to expand outside the blood vessel, increasing the diameter of the implanted coated stent 300, and then withdrawing the balloon 110 so that the blood flow can flow smoothly through the coated stent 300, improving distal perfusion (as shown in FIG. Figure 5 as shown).

[0050] Through the above-mentioned setting, the second balloon can push the blood vessel wall at the occluded site to bulge outward or even rupture, so that the coated stent 300 obtains space to bulge outward from the blood vessel, increasing the diameter of the coated stent 300 after implantation, and ultimately improving the patency of blood flow in the coated stent 300 implanted in the occluded section 400 of the blood vessel, thereby preventing internal blockage of the coated stent 300 after surgery.

[0051] In a specific embodiment, the second balloon is provided with a cutting piece 140 on the side opposite to the first balloon. The pressure generated by the contact between the cutting piece 140 and the vascular membrane can cause the vascular adventitia and the outer part of the tunica media to rupture along the pressure direction, which can effectively achieve accurate alignment between the cutting piece 140 and the lesion position, and the cutting piece 140 can cut the lesion in a direction, greatly improving the effect of stenosis and dilation of the blood vessel during angioplasty.

[0052] like Figure 1 The cutting member 140 is disposed on the outer wall of the second balloon and arranged in an axial direction parallel to the second balloon. Specifically, the cutting member 140 is a metal wire, which can be connected to the second balloon by welding or gluing.

[0053] In a specific embodiment, the cross section of the first balloon is an ellipse with a notch; and / or the cross section of the second balloon is a circle or an ellipse with a notch. The first balloon and the second balloon are connected to each other at the notch to form a whole.

[0054] Further, the eccentricity of the first balloon is greater than that of the second balloon, and the first balloon provides effective support for the second balloon. Further, the outer diameter of the first balloon is greater than the outer diameter of the second balloon.

[0055] In this case, the balloon 110 is designed to have a "gourd"-like cross section, and a metal wire is bonded to the top of the "gourd" in the longitudinal direction. The reason for adopting this design is that the balloon 110 needs to generate enough pressure when in use so that the metal wire is enough to break the adventitia and the outer part of the vascular media.

[0056] If the method of directly installing the metal wire on the traditional balloon with a circular cross section is adopted, the expected technical effect of the present case cannot be achieved. Therefore, the balloon 110 itself is designed to have a cross section consisting of a large-sized ellipse with a large eccentricity and a small-sized circle or ellipse (i.e. Figure 2 The overall shape shown is like a "gourd" shape), so that the balloon 110 has a sufficient thickness after being filled with the filling material to generate a sufficient pressure to cut the blood vessel wall.

[0057] The first balloon is an elliptical balloon with a notch. Since the elliptical part of the "gourd"-shaped balloon 110 has a wider long axis design, compared with the traditional round balloon, the elliptical shape is not easy to spin and slide in the lumen after expansion, and it is easy to position the direction of the metal wire.

[0058] The present solution further comprises a handle, and a balloon filling port 131 for communicating with the balloon filling cavity is disposed at the distal end of the handle or the outer tube 130 , and the liquid / filling material for expanding the balloon 110 is injected through the balloon filling port 131 .

[0059] The balloon 110 is delivered to the stenotic or blocked blood vessel occlusion segment 400 through the handle, the inner tube 120 and the outer tube 130, and then a filling material is injected into the balloon 110 for expansion to relieve the stenosis or blockage of the blood vessel, thereby improving blood flow and relieving symptoms.

[0060] In addition, in a specific embodiment, the present solution also provides a method for dilating a blood vessel occlusion segment, wherein when the novel balloon catheter in the above specific embodiment is used to perform an interventional method to implant a stent graft 300 to treat atherosclerotic diseases, the method comprises:

[0061] Step 1: Use a common balloon to perform subintimal angioplasty to bypass the sclerotic plaque in the occluded segment 400 of the blood vessel, prevent it from affecting the expansion of the stent graft 300, and increase the patency rate by increasing the rate of new lumen acquisition. At this time, the new lumen formed by the subintimal angioplasty is under the combined effect of the pressure and elasticity of the sclerotic plaque, the vascular adventitia and part of the outer vascular middle membrane in the occluded segment 400. The cross-section of the new lumen is crescent-shaped. Subsequently, the stent graft 300 is implanted along the guide wire to achieve the implantation of the stent graft 300 in the occluded segment 400 of the blood vessel.

[0062] It should be noted that after implanting the covered stent 300, due to the combined effects of the sclerotic plaque in the affected area, the adventitia and part of the vascular media, the new lumen created by the subintimal plasty is relatively tight and narrow, and the stent does not expand well. In order to solve the above problem, step 2 needs to be further implemented.

[0063] Step 2: Push the balloon 110 into the stent graft 300 so that the second balloon on the balloon 110 faces the vascular wall (in the solution where the second balloon is equipped with a metal wire, the metal wire also needs to face the vascular adventitia);

[0064] After reaching the occluded segment 400 of the blood vessel, the filling material is injected into the balloon 110, and the second balloon can be pushed outward from the inside of the stent graft 300 to the outside of the blood vessel wall, so that the adventitia and part of the outer vascular media are ruptured, and the stent graft 300 obtains space and bulges out of the blood vessel;

[0065] After the diameter of the implanted stent graft 300 is increased, the balloon 110 is withdrawn to allow blood to flow smoothly through the stent graft 300 .

[0066] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0067] The principles and implementation methods of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the method and core ideas of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A novel balloon catheter, characterized in that: It comprises a balloon (110), an inner tube (120) and an outer tube (130); The balloon (110) comprises a first balloon and a second balloon that are relatively buckled, the cross section of the balloon (110) is a gourd shape surrounded by two semicircular rings, the center of the first balloon has a guidewire cavity for passing a guidewire (200), the balloon (110) is a filling cavity except for the guidewire cavity, and the second balloon is used to expand the blood vessel wall outward at the blocked section of the blood vessel; The outer tube (130) is sleeved on the outer side of the inner tube (120), a balloon filling cavity is formed between the inner tube (120) and the outer tube (130), the filling cavity of the balloon (110) is connected to the balloon filling cavity, and the inner cavity of the inner tube (120) is connected to the guide wire cavity of the balloon.

2. The novel balloon catheter according to claim 1, characterized in that: The second balloon is provided with a cutting piece (140) on a side opposite to the first balloon.

3. The novel balloon catheter according to claim 2, characterized in that: The cutting element (140) is disposed on the outer wall of the second balloon and arranged along an axial direction parallel to the second balloon.

4. The novel balloon catheter according to claim 2, characterized in that: The cutting member (140) is a metal wire.

5. The novel balloon catheter according to claim 1, characterized in that: The cross section of the first balloon is an ellipse with a notch; And / or, the cross-section of the second balloon is circular or elliptical with a notch.

6. The novel balloon catheter according to claim 5, characterized in that: The eccentricity of the first balloon is greater than the eccentricity of the second balloon.

7. The novel balloon catheter according to claim 5, characterized in that: The outer diameter of the first balloon is greater than the outer diameter of the second balloon.

8. The novel balloon catheter according to claim 1, characterized in that: It also includes a handle, and the distal end of the handle or the outer tube (130) is provided with a balloon filling port (131) for communicating with the balloon filling cavity.

9. A method for dilating an occluded segment of a blood vessel, characterized in that: Using the novel balloon catheter according to any one of claims 1 to 8, the method comprises: Implanting a covered stent (300) in the occluded segment (400) of the blood vessel; Pushing the balloon (110) into the stent graft (300) so that the second balloon on the balloon (110) faces the blood vessel wall; After reaching the occluded section (400) of the blood vessel, a filling material is injected into the balloon (110), and the second balloon can be pushed outward from the inside of the stent graft (300) toward the outside of the blood vessel wall, so that the adventitia of the blood vessel and part of the outer vascular media are ruptured, and the stent graft (300) obtains space and bulges outward from the blood vessel; After the diameter of the implanted stent (300) is increased, the balloon (110) is withdrawn to allow blood to flow smoothly through the stent (300).

10. The method for dilating an occluded blood vessel segment according to claim 9, characterized in that: The method of implanting a covered stent (300) in a blood vessel occlusion segment (400) specifically comprises: Subintimal angioplasty is performed using a common balloon to bypass the sclerotic plaque of the occluded blood vessel segment (400). Under the combined effect of pressure and elasticity of the sclerotic plaque, the vascular adventitia, and part of the outer vascular media of the occluded blood vessel segment (400), the new lumen formed by the subintimal angioplasty has a crescent-shaped cross-section, and the coated stent (300) is then implanted along the guide wire.

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