CN215653320U - Dilatation balloon and balloon dilatation catheter - Google Patents

Abstract

The utility model provides an expansion balloon and a balloon expansion catheter, wherein the expansion balloon comprises an outer balloon and an inner balloon; the outer balloon is sleeved outside the inner balloon, the inner balloon expands when being filled with filling fluid and drives the outer balloon to expand, and the inner balloon has a first presetting state in the expansion process; after the inner balloon is expanded to the first preset state and reaches a critical state, the filling fluid in the inner balloon flows out of the outer balloon and fills the outer balloon. Therefore, the expansion form of the expansion balloon is limited by the first presetting state before the inner balloon is expanded to the critical state, and the problem that the balloon is easy to move is solved; and then when the inner balloon reaches a critical state, the filling fluid in the inner balloon flows out to the outer balloon and fills the outer balloon, so that the limitation of the expansion form of the expansion balloon is removed, the expansion balloon can expand along with the form of the outer balloon, and the formation of perivalvular leakage is reduced.

Description

Dilatation balloon and balloon dilatation catheter

Technical Field

The utility model relates to the technical field of medical instruments, in particular to an expansion balloon and a balloon expansion catheter.

Background

Aortic Stenosis (AS) is one of the most common valvular heart diseases among heart valvular diseases, and seriously harms human health. For patients with severe aortic stenosis, surgical aortic valve replacement has been the only treatment to prolong their lives, but older patients often have contraindications for surgery due to advanced age, poor health, severe disease, or other complications. An increasing number of clinical results demonstrate that interventional therapy is an effective treatment for patients at these high risks or who are at too great a risk for traditional open chest surgery. Existing interventional procedures include aortic valvuloballoon angioplasty (BAV) and transcatheter aortic valve placement (TAVI). Balloon dilatation catheters are required in both aortic valvuloballoon angioplasty (BAV) and transcatheter aortic valve placement (TAVI). In aortic valvuloballoon angioplasty (BAV), a diseased native aortic valve is directly dilated with a balloon. In a transcatheter aortic valve implantation procedure (TAVI), on one hand, a balloon is used for pre-expansion to expand calcified valve leaflets and create a good access condition for implantation of a prosthetic valve; on the other hand, after the aortic valve is implanted, the valve balloon catheter is expanded to ensure that the artificial valve is well unfolded and the adherence is improved, so that the treatment effect is improved.

The aortic valve sacculus expansion catheter consists of an expandable valve sacculus, a double-cavity tube body and two connecting pieces, wherein the valve sacculus is required to have the performances of low compliance, size stability, quick expansion and recovery, puncture resistance, explosion resistance, no movement, synchronous expansion and the like; the size of the inner cavity of the double-cavity tube body is compatible with the guide wire with the corresponding specification, and the outer cavity needs to be unobstructed to ensure that the filling and pumping-back time is as short as possible.

At present, the valve balloon structure mostly adopts a straight cylinder type design or an 8-shaped design, and an inner tube is usually a circular hollow tube. The straight-tube structure is beneficial to the even expansion of the saccule at the lesion part, and the excessive expansion and tearing of valve leaflets are avoided. However, when the cylindrical balloon is expanded, the balloon is easily moved when being squeezed by the heavily calcified valve leaflets, so that the balloon deviates from the lesion position, and the effect of expanding the lesion valve leaflets cannot be achieved. 8 style of calligraphy sacculus structure accessible middle waist section (waist) pin pathological change position, reduce the emergence probability of drunkenness to a certain extent, nevertheless because the waist section size of 8 style of calligraphy structure is shorter, expand to serious calcification pathological change limited, and have obvious diameter difference when the sacculus expands out completely in the middle of waist section and both ends, form complication such as valve week leakage easily.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide an expansion balloon and a balloon expansion catheter, and aims to solve the problems that the existing balloon expansion catheter is easy to shift and form perivalvular leakage and the like.

In order to solve the above technical problem, the present invention provides an expansion balloon, including: an outer balloon and an inner balloon;

the outer balloon is sleeved outside the inner balloon, the inner balloon expands when being filled with filling fluid and drives the outer balloon to expand, and the inner balloon has a first presetting state in the expansion process; after the inner balloon is expanded to the first preset state and reaches a critical state, the filling fluid in the inner balloon flows out of the outer balloon and fills the outer balloon.

Optionally, in the expanding balloon, the inner balloon continues to expand after expanding to the first predetermined state until reaching the critical state, and the inner balloon is burst to allow the filling fluid inside the inner balloon to flow out into the outer balloon and fill the outer balloon.

Optionally, in the dilatation balloon, the inner balloon axially comprises a first shoulder section, a girdling section and a second shoulder section which are sequentially connected, and the wall thickness of at least the first shoulder section or the second shoulder section is not more than 0.02 mm; alternatively, the inner balloon has a region of weakness thereon.

Optionally, in the dilation balloon, the region of weakness is linear.

Optionally, in the expansion balloon, a critical pressure when the inner balloon is expanded to the critical state is smaller than a preset pressure for rated expansion of the outer balloon.

Optionally, in the dilation balloon, the inner balloon has a liquid through hole, the dilation balloon further includes a sealing portion, the sealing portion seals the liquid through hole after the inner balloon is dilated to the first preset state until the critical state is reached, and when the inner balloon reaches the critical state, the sealing of the liquid through hole is released, so that the filling fluid inside the inner balloon flows out into the outer balloon and fills the outer balloon.

Optionally, in the dilatation balloon, the closure portion comprises a plug, a sealing patch, or a water-soluble patch.

Optionally, in the dilatation balloon, the closure further comprises an anchor through which the plug is connected with the outer balloon or the inner balloon.

Optionally, in the dilatation balloon, the closing part further comprises a traction wire, and the sealing sticker is attached to the inner wall of the inner balloon and covers the liquid through hole; one end of the traction wire is connected with the sealing paste, and the other end of the traction wire extends to the near end and is used for being dragged by an operator to pull the sealing paste to remove the covering of the liquid through hole.

Optionally, in the dilating balloon, the inner balloon is a non-compliant balloon, the inner balloon in the first preset state is in a dumbbell shape with two expanded ends and a concave middle, the outer balloon is a non-compliant balloon, the outer balloon is dilated to a second preset state after the inner balloon reaches a critical state, and the outer balloon in the second preset state is in a straight tube shape.

In order to solve the above technical problem, the present invention also provides an expansion balloon, including: an outer balloon and an inner balloon; the outer balloon is sleeved outside the inner balloon, and the inner balloon is filled with filling fluid to drive the outer balloon to expand; wherein the inner balloon has a first pre-shaped state during expansion; the material of the outer balloon is selected from at least one of PE, PET, PA, or Pebax; the material of the inner balloon is selected from at least one of PE, PET, PA, or Pebax.

In order to solve the technical problem, the utility model also provides an expansion balloon, which comprises an outer balloon and an inner balloon; the outer balloon is sleeved outside the inner balloon; the inner balloon is configured to have a threshold condition during inflation with an inflation fluid for causing the inflation fluid therein to flow into the outer balloon when the inner balloon reaches the threshold condition.

Optionally, in the dilation balloon, the outer balloon is configured to have a first shape before the inner balloon is in the critical state and a second shape after the inner balloon is in the critical state, the first shape being defined by the inner balloon and being different from the second shape.

In order to solve the above technical problems, the present invention also provides a balloon dilatation catheter comprising: an expansion balloon as described above, and a catheter in communication with the proximal end of the inner balloon, the catheter being configured to transmit an inflation fluid to drive expansion or contraction of the expansion balloon.

In summary, in the dilatation balloon and the balloon dilatation catheter provided by the utility model, the dilatation balloon comprises an outer balloon and an inner balloon; the outer balloon is sleeved outside the inner balloon, the inner balloon expands when being filled with filling fluid and drives the outer balloon to expand, and the inner balloon has a first presetting state in the expansion process; after the inner balloon is expanded to the first preset state and reaches a critical state, the filling fluid in the inner balloon flows out of the outer balloon and fills the outer balloon.

With the arrangement, the expansion form of the expansion balloon is limited by the first presetting state before the inner balloon is expanded to the critical state, so that the problem that the balloon is easy to move is solved; and then when the inner balloon reaches a critical state, the filling fluid in the inner balloon flows out to the inner part of the outer balloon and fills the outer balloon, so that the restriction of the inner balloon on the expansion form of the expansion balloon is removed, the expansion balloon can expand along with the form of the outer balloon, and the formation of perivalvular leakage is reduced.

Drawings

It will be appreciated by those skilled in the art that the drawings are provided for a better understanding of the utility model and do not constitute any limitation to the scope of the utility model. Wherein:

FIG. 1 is a schematic view of a balloon dilation catheter in accordance with an embodiment of the present invention;

FIG. 2 is a schematic view of an expansion balloon of an embodiment of the present invention with the inner balloon in a pre-shaped state;

FIG. 3 is a schematic axial cross-section of an expansion balloon of an embodiment of the utility model with the inner balloon in a pre-set state;

FIG. 4 is a schematic view of the dilation balloon of one embodiment of the present invention with the outer balloon in an expanded state;

fig. 5 is a schematic view of a seal patch and a pull wire according to an embodiment of the present invention.

In the drawings:

1-expanding the balloon; 4-a guidewire lumen; 5-a connector; 6-a developing ring; 7-a catheter; 71-an inner tube; 72-an outer tube; 8-a sheath; 9-liquid through cavity;

10-an outer balloon; 11-a first cone section; 12-a straight section; 13-a second conical section;

20-an inner balloon; 21-a third cone segment; 22-a body section; 221-a first shoulder section; 222-a first transition section; 223-a corset section; 224-a second transition section; 225-a second shoulder section; 23-a fourth cone segment; 24-liquid through hole; 25-a closure; 251-sealing paste; 252-pull wires.

Detailed Description

To further clarify the objects, advantages and features of the present invention, a more particular description of the utility model will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is to be noted that the drawings are in greatly simplified form and are not to scale, but are merely intended to facilitate and clarify the explanation of the embodiments of the present invention. Further, the structures illustrated in the drawings are often part of actual structures. In particular, the drawings may have different emphasis points and may sometimes be scaled differently.

As used in this application, the singular forms "a", "an" and "the" include plural referents, the term "or" is generally employed in a sense including "and/or," the terms "a" and "an" are generally employed in a sense including "at least one," the terms "at least two" are generally employed in a sense including "two or more," and the terms "first", "second" and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicit to the number of technical features indicated. Thus, features defined as "first", "second", "third" may explicitly or implicitly include one or at least two of such features, the term "proximal" generally being the end near the operator, the term "distal" generally being the end near the patient, i.e. near the lesion, the terms "end" and "proximal" and "distal" generally referring to the corresponding two parts, which include not only the end points, the terms "mounted", "connected" and "connected" being to be understood in a broad sense, e.g. as being fixedly connected, as well as detachably connected, or as an integral part; either directly or indirectly through intervening media, either internally or in any other relationship. Furthermore, as used in the present invention, the disposition of an element with another element generally only means that there is a connection, coupling, fit or driving relationship between the two elements, and the connection, coupling, fit or driving relationship between the two elements may be direct or indirect through intermediate elements, and cannot be understood as indicating or implying any spatial positional relationship between the two elements, i.e., an element may be in any orientation inside, outside, above, below or to one side of another element, unless the content clearly indicates otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

The utility model provides an expansion balloon and a balloon expansion catheter, and aims to solve the problem that the existing 8-shaped balloon expansion catheter cannot adapt to multiple deformation.

The following description refers to the accompanying drawings.

Referring to fig. 1to 5, fig. 1 is a schematic view of a balloon dilation catheter according to an embodiment of the present invention; FIG. 2 is a schematic view of an expansion balloon of an embodiment of the present invention with the inner balloon in a pre-shaped state; FIG. 3 is a schematic axial cross-section of an expansion balloon of an embodiment of the utility model with the inner balloon in a pre-set state; FIG. 4 is a schematic view of the dilation balloon of one embodiment of the present invention with the outer balloon in an expanded state; fig. 5 is a schematic view of a seal patch and a pull wire according to an embodiment of the present invention.

As shown in fig. 1, a balloon dilation catheter according to one embodiment of the present invention includes: the balloon 1 and the catheter 7 are expanded. The dilatation balloon 1 comprises: an outer balloon 10 and an inner balloon 20; the catheter 7 is in communication with the proximal end of the inner balloon 20, the catheter 7 being configured to deliver an inflation fluid to drive expansion or contraction of the dilation balloon 1. The outer balloon 10 is sleeved outside the inner balloon 20, the inner balloon 20 expands when being filled with filling fluid and drives the outer balloon 10to expand, and the inner balloon 20 is set to have a critical state in the filling fluid filling process, so that the filling fluid in the inner balloon flows into the outer balloon 10 when the inner balloon reaches the critical state. Wherein the inner balloon 20 has a first pre-shaped state during expansion; when the inner balloon 20 reaches a critical state after being expanded to the first preset state, the filling fluid inside the inner balloon 20 flows out into the outer balloon 10 and fills the outer balloon 10. Note that, the inner balloon 10 and the outer balloon 10 are fitted to the outside of the inner balloon 20, and it means that the distance between the outer balloon 10 and the axis of the inflatable balloon 1 is larger than the distance between the inner balloon 20 and the axis of the inflatable balloon 1 in the same radial cross section of the inflatable balloon 1. It will be understood by contrast that when one member is located within another member, the distance from the axis of the inner member is less than the distance from the axis of the outer member.

Preferably, the outer balloon 10 and the inner balloon 20 are both non-compliant balloons, and it should be noted that, for a single balloon (e.g., the outer balloon 10 or the inner balloon 20), when filled with a filling fluid (e.g., a filling liquid) at a nominal pressure (i.e., a rated pressure), the balloon will expand to a certain size, typically, the cross section of the balloon is substantially circular, and the diameter (i.e., an outer diameter) thereof is the nominal diameter of the balloon. And (3) continuously filling the balloon with the filling fluid at the nominal diameter to further expand the balloon, and finally, the balloon is burst by the filling fluid, and when the balloon is burst, the pressure in the balloon is the rated burst pressure. In this embodiment, a compliant balloon means that the diameter of the balloon at the rated burst pressure is greater than 30% of the nominal diameter, while a non-compliant balloon means that the diameter of the balloon at the rated burst pressure is no greater than 15% of the nominal diameter.

The inner balloon 20 may be pre-shaped according to the structural configuration of the intended site of expansion (i.e., lesion site). Referring to fig. 2 and 3, in an example, when the expanding balloon 1 is applied to the field of heart valve disease treatment, such as aortic valve replacement surgery, the inner balloon 20 in the first predetermined state is in a dumbbell shape with two expanded ends and a middle concave, and includes a main body section 22, the main body section 22 includes a first shoulder section 221, a girdling section 223 and a second shoulder section 225 in sequence along the axial direction, when the inner balloon 20 is in the first predetermined state, the radial dimension of the first shoulder section 221 is greater than that of the girdling section 223, and the radial dimension of the second shoulder section 225 is greater than that of the girdling section 223. The radial dimension herein refers to the distance between the outer sidewalls of the inner balloon 20 through the axis of the inner balloon 20. Optionally, the cross section of the inner balloon 20 is circular, the radial dimension of each section refers to the diameter thereof, and the first shoulder section 221, the corset section 223 and the second shoulder section 225 are cylindrical and straight-cylindrical; preferably, the diameter of the first shoulder section 221 is the same as the diameter of the second shoulder section 225. When the inner balloon 20 is inflated, due to the pre-shaping design of the inner balloon 20, a dumbbell-shaped state as shown in fig. 2 and 3 is formed, and the waist-binding section 223 can be clamped at the heart valve annulus, so that the expansion balloon 1 can be prevented from leaving the focus due to the movement.

Optionally, the outer balloon 10 is also a non-compliant balloon, which is used to directly contact human tissue during use, and needs to have a high puncture strength and a certain compressive strength to avoid being punctured by some human tissue, such as calcified valve annulus, and preferably, the outer balloon 10 is configured to have a first shape before the inner balloon 20 is in a critical state, and a second shape after the inner balloon 20 is in a critical state, the first shape being defined by the inner balloon 20 and different from the second shape. Further, after the inner balloon 20 reaches the critical state, the outer balloon 10 continues to expand until reaching a second preset state, and the outer balloon 10 in the second preset state is in a straight cylinder shape (i.e. a second shape) and comprises a straight cylinder shape straight section 12. In a preferred embodiment, the outer balloon 10 further comprises a first conical section 11 and a second conical section 13, and the first conical section 11, the straight section 12 and the second conical section 13 are sequentially connected along the axial direction of the outer balloon 10. When the outer balloon 10 is inflated to the second predetermined configuration (i.e., fully inflated, with the internal filling pressure at nominal pressure), the first and second tapered segments 11, 13 are substantially tapered, and the straight segment 12 is substantially cylindrical. The shape of the outer balloon 10 is currently the most common predominant shape of balloons. The morphology can be understood by those skilled in the art from the prior art. Referring to fig. 4, the radial dimension of the straight section 12 is uniform when the outer balloon 10 is in the second pre-shaped state. It should be understood that, rather than being in a uniform radial dimension configuration at all times during the expansion of the inflatable balloon 1, the outer balloon 10 and the inner balloon 20 may remain substantially similar in configuration during the expansion of the inner balloon 20 to the first predetermined configuration, and the configuration of the flat section 12 may also be similar to the first predetermined configuration of the inner balloon 20, such as may be similar to a dumbbell shape (i.e., the first shape). Further, when the inner balloon 20 reaches the critical state, the filling fluid inside the inner balloon 20 flows out to the outer balloon 10 and fills the outer balloon 10, and the outer balloon 10 continues to expand, the straight section 12 gradually transitions to the cylindrical straight cylinder shape until the radial dimension of the straight section 12 is uniform. By the design, after the inner balloon 20 reaches the critical state, the expansion state of the whole expansion balloon 1 is similar to that of the traditional straight-tube balloon, and in the pre-expansion of BAV operation or TAVI operation, an operator can select the balloon specification most suitable for treatment according to the size of the original valve leaflets and/or valve rings of lesions more easily, so that the lesion parts can be expanded more quickly and uniformly; after the aortic valve in the TAVI operation is implanted, the artificial biological valve can be fully expanded, and the complications such as paravalvular leakage and the like are avoided, so that the TAVI operation quality is improved. Alternatively, the critical pressure at which the inner balloon 20 reaches the critical state may be set in combination with the use case, for example, may be set in the range of 0.5atm to 1 atm. The rated burst pressure that the outer balloon 10 can withstand, depending on the requirements of use, is at least 3atm or more.

Correspondingly, the inner balloon 20 includes a third conical section 21 and a fourth conical section 23 at two ends thereof, which are adapted to the shapes of the first conical section 11 and the second conical section 13, and after the inner balloon 20 is expanded (e.g., in the first predetermined state or to be expanded to the first predetermined state), the third conical section 21 and the fourth conical section 23 are substantially tapered and adapted to the shapes of the first conical section 11 and the second conical section 13. The distal end of the first shoulder section 221 is connected to the proximal end of the third conical section 21 and the proximal end of the second shoulder section 225 is connected to the distal end of the fourth conical section 23. Preferably, the main body segment 22 further comprises two transition segments, namely a first transition segment 222 and a second transition segment 224, wherein the first transition segment 222 connects the first shoulder segment 221 and the corset segment 223, respectively, and the second transition segment 224 connects the corset segment 223 and the second shoulder segment 225, respectively. The arrangement of the two transition sections can form a transition connection between the shoulder section and the corset section 223, and when the radial sizes of the shoulder section and the corset section 223 are different, the transition section is preferably in a conical shape, wherein the smaller end of the conical shape is connected with the corset section 223, and the larger end is connected with the shoulder section.

An exemplary balloon dilation catheter provided in this embodiment is described below with reference to fig. 1, 3 and 4, it being understood that the balloon dilation catheter shown in fig. 1 does not represent the actual state of the balloon dilation catheter in use, but only illustrates the structural components of the balloon dilation catheter.

Optionally, the catheter 7 is a double-layer structure, and includes an inner tube 71 and an outer tube 72, the outer tube 72 is sleeved outside the inner tube 71, and a gap is formed between the inner tube 71 and the outer tube 72, and the gap is used for the transmission of the filling fluid. The inner tube 71 penetrates out of the distal end of the outer tube 72 and extends into the inner balloon 20, the distal end of the inner balloon 20 is fixedly and hermetically connected with the inner tube 71, and the distal end of the outer balloon 10 is fixedly and hermetically connected with the distal end of the inner balloon 20; the proximal end of the inner balloon 20 is fixedly and sealingly connected to the outer tube 72, and the proximal end of the outer balloon 10 is fixedly and sealingly connected to the proximal end of the inner balloon 20. The inner tube 71 is mainly used for the guide wire to pass through, and optionally, the inner tube 71 is further provided with a developing ring 6. When inflation fluid is delivered to the inner balloon 20 through the catheter 7 (referring to the gap between the inner tube 71 and the outer tube 72), the inner balloon 20 and the outer balloon 10 expand, whereas when inflation fluid is withdrawn from the inner balloon 20 through the catheter 7, the inner balloon 20 and the outer balloon 10 contract. Preferably, a vacuum is pre-pumped between the outer balloon 10 and the inner balloon 20, the outer balloon 10 is attached to the inner balloon 20, and the outer balloon 10 is closely attached to the inner balloon 20, so that during the expansion and contraction of the expansion balloon 1, the outer balloon 10 and the inner balloon 20 expand and contract synchronously, which is beneficial to better control of the shape of the expansion balloon 1. Note that the "pre-evacuation" herein does not mean absolute vacuum in a narrow sense, but is broadly understood to mean a case where the relative atmospheric pressure is negative. The term "vacuum" as used herein is understood to mean rough vacuum (10Torr to 760Torr) or moderate vacuum (1Torr to 10Torr) due to process limitations.

Further, the balloon dilatation catheter further comprises accessories such as a sheath 8, a liquid through cavity 9, a guide wire cavity 4 and a connecting piece 5, the sheath 8 comprises a three-way component inside, and the liquid through cavity 9, the guide wire cavity 4 and the catheter 7 are connected to the three-way component respectively. Optionally, the guide wire cavity 4 and the inner tube 71 of the catheter 7 are positioned on the trunk branch of the three-way component and are communicated with each other, and the three-way component is in a straight-through configuration; the liquid through cavity 9 is positioned on the side branch of the three-way component, and the liquid through cavity 9 is communicated with the outer tube 72 of the catheter 7. The proximal ends of the liquid passage cavity 9 and the guide wire cavity 4 are respectively connected with a connecting piece 5 and are respectively used for being connected with components matched with the outside, and the components of the balloon dilatation catheter can be selected and configured by a person skilled in the art according to the prior art.

Embodiments in which the inflation fluid inside the inner balloon 20 flows out into the outer balloon 10 and inflates the outer balloon 10 when the inner balloon 20 reaches a critical state are described below in connection with several exemplary embodiments.

In one embodiment, the inner balloon 20 continues to be inflated with the inflation fluid after being inflated to the first predetermined state, and continues to be inflated until the inflation reaches a critical state, so that the inflation fluid inside the inner balloon 20 flows out into the outer balloon 10 and inflates the outer balloon 10. The inner balloon 20 is divided into two categories of integral blasting and local blasting according to the blasting form.

In the example of the inner balloon 20 being entirely burst, the inner balloon 20 is made of a uniform material and has poor pressure resistance, or has poor local pressure resistance, so that the inner balloon 20 is caused to burst entirely when the inner balloon 20 is inflated to a critical pressure. Preferably, the inner balloon 20 is burst in a fragment-free, axial burst. Preferably, the critical pressure when the inner balloon 20 is expanded to the critical state is less than the preset pressure of the rated expansion of the outer balloon 10 (i.e. the nominal pressure when the outer balloon 10 is fully expanded), and when the inner balloon 20 is expanded to the critical state and burst, the outer balloon 10 is not yet expanded to the preset pressure of the rated expansion. The danger caused by the fact that the outer balloon 10 is exploded along with the explosion when the inner balloon 20 is exploded is avoided, and the safety of expanding the balloon is improved. Of course, in other embodiments, the critical pressure of the inner balloon 20 may not be limited to be less than the predetermined pressure for the rated expansion of the outer balloon 10, and the pressure in the outer balloon 10 may drop instantaneously due to the incompressible property of the liquid because of the volume difference between the inner and outer balloons when the inner balloon 20 bursts. Therefore, if the critical pressure of the inner balloon is set to be higher than the preset pressure for rated expansion of the outer balloon 10, the effect of safe use can also be achieved. And so arranged, the deployment of the outer balloon 10 from the dumbbell shape to the straight cylindrical shape can be made more controllable.

In one example, the inner balloon 20 has a reduced wall thickness to reduce the pressure resistance of the inner balloon 20. Alternatively, the material of inner balloon 20 may be the same as that of outer balloon 10. However, the overall wall thickness of the inner balloon 20 is smaller than that of the outer balloon 10, for example, the wall thickness of a single layer of the inner balloon 20 is not greater than 0.02mm, so as to achieve the effect of overall explosion after reaching a critical state.

In another example, unlike the previous example, the wall thickness of at least the first shoulder section 221 or the second shoulder section 225 of the inner balloon 20 is set to be no greater than 0.02mm without limiting the overall wall thickness of the inner balloon 20 to no greater than 0.02 mm. Specifically, since the inner balloon 20 is typically formed by blow molding a thermoplastic polymer, the first shoulder section 221 and the second shoulder section 225, which are the portions of the inner balloon 20 with the largest outer diameter, are typically the thinnest wall thickness, and the shoulder section with the largest outer diameter will break first due to the force. The wall thickness of the first shoulder section 221 or the second shoulder section 225 is limited to be not more than 0.02mm, so that the overall blasting effect of the inner balloon 20 after reaching the critical state can be realized. In practice, of course, the wall thickness of other portions of the inner balloon 20 may be set to be no greater than 0.02mm, with similar bursting effects.

In other embodiments, the inner balloon 20 has a region of weakness therein. By weakened areas, it is meant that the area is mechanically weaker than the rest of the area, and the weakened areas may rupture first upon expansion, such as may be formed by reducing the wall thickness at the surface of the inner balloon 20. Because the pressure inside the inner balloon 20 is substantially equal everywhere during filling, the existence of any weak area can make the inner balloon 20 achieve the effect of integral blasting after reaching the critical state. Alternatively, the areas of weakness may be distributed in spots on the inner balloon 20, preferably the areas of weakness are linear. More preferably, the inner balloon 20 has a plurality of linear weakened areas, and the plurality of weakened areas are uniformly arranged around the circumference of the inner balloon 20, so as to achieve uniform blasting after the inner balloon 20 reaches a critical state, and the blasting position is controllable, so as to ensure that the filling fluid uniformly contacts the outer balloon 10 when the inner balloon 20 is blasted, and the outer balloon 10 can be uniformly expanded.

In the example of the inner balloon 20 being partially ruptured, the inner balloon 20 has a liquid through hole 24 thereon, and the inflatable balloon further includes a closing portion 25, wherein the closing portion 25 closes the liquid through hole 24 after the inner balloon 20 is inflated to the first predetermined state until the critical state is reached, and when the inner balloon 20 reaches the critical state, the closing of the liquid through hole 24 is released, so that the filling fluid inside the inner balloon 20 flows out into the outer balloon 10 and fills the outer balloon 10. Specifically, before the inner balloon 20 is expanded to the critical state, the liquid through holes 24 are covered by the closed parts 25, and when the inner balloon 20 reaches the critical state, the liquid through holes 24 are opened, and the inner balloon 20 can release the filling fluid outwards through the liquid through holes 24. The closure portion 25 may include a plug, a sealing patch 251, or a water soluble patch, depending on the form of the partial rupture of the inner balloon 20.

In one example, the closure portion 25 comprises a plug, such as a somewhat flexible plug, which may be silicone or latex, secured to the inner balloon 20 by being inserted into the through-hole 24; after the inner balloon 20 is inflated to the first predetermined state, it continues to be inflated with the inflation fluid, and when the pressure inside the inner balloon 20 gradually rises to reach the critical pressure, the plug is pushed out of the fluid passage hole 24 to the area between the inner and outer balloons, whereupon the inflation fluid flows out of the inner balloon 20 from the fluid passage hole 24, directly contacts the outer balloon 10, inflates the outer balloon 10, and as the inflation fluid continues to inflate, the outer balloon 10 continues to inflate.

Further, the closure portion 25 further comprises an anchor by which the plug is connected with the outer balloon 10 or the inner balloon 20. When using a plug to block the access hole 24 in an embedded manner, additional anchors may further be used to limit the dislodgement of the plug. The anchor, which may be a thread glued inside the outer balloon 10 or outside the inner balloon 20, prevents the plug from falling out into the body when the outer balloon 10 is also ruptured. Preferably, the inner balloon 20 has only one of the liquid through holes 24, and the closing portion 25 includes only one of the plugs. Since the pressures inside and outside the inner balloon 20 will quickly equalize when one of the plugs fails, only one of the ports 24 will be effective and no more plugs can be expelled from its corresponding port 24. For the sake of simplicity, the inner balloon 20 may be provided with only one through hole 24, and the closing portion 25 may also include only one stopper.

In another example, unlike the previous example, the sealing portion 25 includes a sealing strip 251, and the sealing strip 251 is preferably adhesively attached to the liquid through hole 24 to form a seal for the liquid through hole 24. The adhesive is mainly used for the purpose of satisfying the sealing performance, the adhesive needs to be insoluble in water or to be filled with fluid (such as iopromide), and the sealing edge of the sealing patch 251 needs to be adhered neatly and tightly. However, in order to facilitate the detachment of the seal 251, the adhesive bond strength of the adhesive needs to be low, for example, an adhesive peel strength of less than 500 Pa. In some embodiments, the seal 251 may be attached to the outside of the inner balloon 20, and the seal 251 may be pushed open directly when the filling pressure within the inner balloon 20 reaches a threshold pressure.

Optionally, the closing part 25 further comprises a traction wire 252, and the sealing sticker 251 is attached to the inner wall of the inner balloon 20 and covers the liquid through hole 24; one end of the pulling wire 252 is connected to the sealing patch 251, and the other end of the pulling wire 252 extends to the proximal end for being pulled by an operator to pull the sealing patch 251 to release the covering of the liquid through hole 24.

Preferably, the inner balloon 20 has a plurality (e.g., 10) of the liquid through holes 24, and each of the liquid through holes 24 has a diameter of 0.5mm to 5 mm. It should be noted that the diameter here is an equivalent diameter. That is, the shape of the liquid through hole 24 is not limited to a circle, and may be a polygon or other shapes, and if the liquid through hole 24 having other shapes is adopted, the diameter of the circle having the same area corresponding to the hole area is the equivalent diameter of the hole. In order to prevent the sealing strip 251 from escaping from the through-hole 24 into the middle area of the inner balloon 20 and the outer balloon 10, on the one hand, the outer contour shape of the sealing strip 251 needs to be larger than the contour shape of the through-hole 24 in order to completely cover the through-hole 24; the other side sealing tape 251 needs not to be easy to deform, and the liquid passing through the liquid passing hole 24 due to deformation is avoided. The sealing paste 251 may be made of metal foil, polymer film, or ceramic sheet. More preferably, a plurality of closely spaced liquid passing holes 24 may be grouped into a liquid passing hole group. The shape and number of the contour of the through-hole groups are not limited, for example, a circle or other polygons can be selected, and at least one sealing patch 251 is attached to each through-hole group, so that all the through-hole groups can be covered by the sealing patches 251.

Correspondingly, the closing part 25 comprises a plurality of pull wires 252, the back side (i.e. the side far from the side attached to the liquid through hole 24) of each sealing sticker 251 is connected to one pull wire 252, and then the pull wires 252 converge to one total pull wire; the main pull wire is led out from a separate outlet (preferably with a haemostatic valve) at the connector 5 of the lumen 9 of the balloon dilatation catheter. In use, when the inner balloon 20 is inflated to a critical state, the operator can pull the main pull wire at the proximal end to disengage the seal 251 and release the covering of the fluid passage hole 24. The provision of the traction wire 252 facilitates, on the one hand, the actuation of the operator who can actively perform the pulling operation at a certain filling pressure, so as to unblock the through-flow opening 24, and thus to allow the critical pressure to assume a precise value that can be controlled and selected. On the other hand, the pull wires 252 are provided to prevent the seal 251 from falling out into the human body when the outer balloon 10 is ruptured.

In other embodiments, the closure portion 25 comprises a water soluble patch, and the inner balloon 20, after expanding to the first predetermined configuration, may be left unfilled with filling fluid and wait a predetermined amount of time until the water soluble patch is gradually dissolved until a threshold condition is reached. The water-soluble patch is made of one material selected from polyacrylic acid, chitosan or polyvinylpyrrolidone (PVP). The water-soluble filling paste is filled at the position of the liquid through hole 24, and after the water-soluble filling paste is contacted with filling fluid (such as filling liquid) for a period of time, the water-soluble filling paste can be dissolved or partially dissolved, so that the mechanical property is reduced, and the sealing of the liquid through hole 24 is relieved.

Optionally, the inner balloon 20 is in a folded state when not inflated, and the outer balloon 10 is correspondingly collapsed, so that the entire dilatation balloon 1 can be collapsed to a smaller outer diameter for the dilatation balloon 1to pass through in the blood vessel. The inner balloon 20 in the folded state is filled with filling fluid, and the inner balloon 20 gradually expands toward the critical state, and simultaneously drives the outer balloon 10 wrapped outside the inner balloon 20 to expand. Conversely, when the inflation fluid is pumped into the inner balloon 20 before the critical state, the inner balloon 20 gradually contracts toward the folded state, and the outer balloon 10 also contracts.

Further, the inner balloon 20 in the first predetermined shape is continuously inflated with the inflation fluid or waits for a certain time until a critical state is reached, the inner balloon 20 will burst or rupture, and the inflation fluid will flow out of the inner balloon 20 and inflate into the interior of the outer balloon 10, so that the outer balloon 10 continues to expand as a whole until the outer balloon 10 expands to the second predetermined shape to reach its nominal diameter. It will be appreciated that during this process, the outer balloon 10 may also contract as the filling fluid is drawn into the inner balloon 20, but the inner balloon 20 will not return to its pre-critical shape and will continue to maintain its ruptured configuration.

Optionally, when the inner balloon 20 is in the folded state, the ratio of the axial length of the inner balloon 20 to the axial length of the outer balloon 10 is between 0.9 and 1.0, and more preferably 0.98. The axial length of the outer balloon 10 and the inner balloon 20 are substantially similar, and typically the outer balloon 10 will be slightly longer than the initial length of the inner balloon 20 (i.e., the axial length of the inner balloon 20 when in the folded state); this is because the compliance of the outer balloon 10 and the inner balloon 20 may be different, and the two balloons may have different expansion capacities in the radial direction and the axial direction during the filling process, so that the lengths of the two filled states (including the critical state and before the critical state of the inner balloon 20) can be ensured to be matched. It should be noted that the initial length of the inner balloon 20 is the initial length before the inner balloon is assembled with the outer balloon 10, specifically, during the assembly process, the proximal ends of the inner balloon 20 and the outer balloon 10 in the folded state are aligned, and the inner balloon 20 is stretched, so that the inner balloon 20 is in a stretched state in the axial direction after the assembly. Optionally, the initial outer diameter of the straight section 12 of the outer balloon 10 (i.e., the outer diameter of the outer balloon 10 when the inner balloon 20 is in the folded state) is greater than or equal to the initial outer diameter of the shoulder section of the inner balloon 20.

Preferably, the ratio of the axial length of the corset section 223 to the sum of the axial lengths of the first shoulder section 221, the corset section 223 and the second shoulder section 225 is between 0 and 0.7; more preferably, the ratio of the axial length of the corset section 223 to the sum of the axial lengths of the first shoulder section 221, the corset section 223, the two transition sections and the second shoulder section 225 is between 0 and 0.7. When the waist-girding segment 223 ratio is near 0, the inner bladder 20 (meaning it is in the first pre-shaped state) changes from a dumbbell-like shape to an 8-like shape. Preferably, the ratio of the axial length of the corset section 223 to the sum of the axial lengths of the first shoulder section 221, the corset section 223, the two transition sections, and the second shoulder section 225 is 0.35. Optionally, when the inner balloon 20 is in the first pre-setting state, the ratio of the outer diameter of the corset section 223 to the nominal diameter of the outer balloon 10 is between 0.3 and 0.75, preferably 0.55; and/or the ratio of the outer diameter of the first and second shoulder sections 221, 225 to the nominal diameter of the outer balloon 10 is between 0.6 and 1.0, preferably 0.8.

A specific embodiment of the dilatation balloon 1 is disclosed below. It is to be understood that the data disclosed below is merely a preferred example of the dilation balloon 1 and is not limiting of the dilation balloon 1.

Axial length of straight section 12 of outer balloon 10 (referring to the dimension of outer balloon 10 in the second pre-set state): between 20 and 55mm, preferably 36 mm; axial length of the first and second cone segments 11 and 13: the diameter of the outer balloon 10 is changed, and is usually between 8mm and 60 mm; the taper angle of the first and second taper sections 11 and 13 (i.e. the angle between the taper of the first and second taper sections 11 and 13 and the axis of the outer balloon 10): between 25 ° and 100 °, preferably 45 °.

The specification of the outer balloon 10 corresponds to the calibration specification of the required balloon (the general balloon is calibrated into different calibration specifications according to the material, the size and the expansion performance of the general balloon, and the specification of the conventional commonly used expansion balloon is generally between 8mm and 34 mm): between 14mm and 26mm, the inventor finds that the outer balloon 10 with the calibrated specification can play a good anti-channeling effect after being matched with the inner balloon 20.

The modulus of elasticity of the outer balloon 10 is greater than 400Mpa, preferably greater than 1500 Mpa. The material of the outer balloon 10 is selected from one or more of the group consisting of high polymer such as PE, PET, PA and Pebax, which satisfies good non-compliance, high puncture strength and a certain compressive strength. The material of the inner balloon 20 may also be selected from one or a combination of more of the high molecular polymers PE, PET, PA and Pebax. The utility model does not limit the material, color, layered or woven structure, etc. of the outer balloon 10 and the inner balloon 20, and those skilled in the art can select appropriate materials to prepare the outer balloon 10 and the inner balloon 20 according to the prior art.

In summary, in the dilatation balloon and the balloon dilatation catheter provided by the utility model, the dilatation balloon comprises an outer balloon and an inner balloon; the outer balloon is sleeved outside the inner balloon, the inner balloon is a preset non-compliant balloon, and the inner balloon expands when being filled with filling fluid and drives the outer balloon to expand; when the inner balloon is expanded to a critical state, filling fluid in the inner balloon flows out of the outer balloon and fills the outer balloon. With the configuration, the inner balloon is a preset non-compliant balloon, and the expansion form of the expansion balloon is limited before the expansion balloon is expanded to a critical state, so that the problem that the balloon is easy to move is solved; and then when interior sacculus continues the expansion, the inside sufficient fluid of interior sacculus flows out to outer sacculus in and sufficient outer sacculus for the restriction of interior sacculus to the expansion form of expansion sacculus is relieved, thereby the form expansion of expansion sacculus can follow outer sacculus, has reduced the formation of valve leakage.

It should be noted that, in the present specification, the embodiments are described in a progressive manner, each embodiment focuses on differences from other embodiments, similar parts between the embodiments may be referred to each other, and different parts between the embodiments may also be used in combination with each other, which is not limited by the present invention. The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.

Claims (14)

1. An dilatation balloon, comprising: an outer balloon and an inner balloon;

the outer balloon is sleeved outside the inner balloon, the inner balloon expands when being filled with filling fluid and drives the outer balloon to expand, and the inner balloon has a first presetting state in the expansion process; after the inner balloon is expanded to the first preset state and reaches a critical state, the filling fluid in the inner balloon flows out of the outer balloon and fills the outer balloon.

2. The dilation balloon of claim 1, wherein the inner balloon continues to expand after expansion to the first predetermined state until reaching the threshold state, bursting to allow the filling fluid inside the inner balloon to flow out into and fill the outer balloon.

3. The dilation balloon of claim 2, wherein the inner balloon comprises a first shoulder section, a girdling section and a second shoulder section connected in series along an axial direction, at least the wall thickness of the first shoulder section or the second shoulder section being no greater than 0.02 mm; alternatively, the inner balloon has a region of weakness thereon.

4. The dilation balloon of claim 3, wherein the weakened areas are linear.

5. The dilation balloon of claim 2, wherein a critical pressure at which the inner balloon is expanded to the critical state is less than a preset pressure at which the outer balloon is rated to expand.

6. The dilatation balloon of claim 1 wherein the inner balloon has a fluid port therein, the dilatation balloon further comprising a closure portion that closes the fluid port after the inner balloon is inflated to the first pre-set condition until the threshold condition is reached, and wherein the closure of the fluid port is released when the inner balloon reaches the threshold condition to allow the inflation fluid within the inner balloon to flow out into and inflate the outer balloon.

7. The dilatation balloon of claim 6 wherein the closure comprises a plug, a sealing patch, or a water soluble patch.

8. The dilatation balloon of claim 7 wherein the closure further comprises an anchor through which the plug is connected to the outer balloon or the inner balloon.

9. The dilatation balloon of claim 7 wherein the closure further comprises a pull wire, the sealing patch is affixed to the inner wall of the inner balloon and covers the fluid port; one end of the traction wire is connected with the sealing paste, and the other end of the traction wire extends to the near end and is used for being dragged by an operator to pull the sealing paste to remove the covering of the liquid through hole.

10. The dilation balloon of claim 1, wherein the inner balloon is a non-compliant balloon, the inner balloon in the first predetermined state is dumbbell-shaped with two expanded ends and a concave middle, the outer balloon is a non-compliant balloon, the outer balloon expands to a second predetermined state after the inner balloon reaches a critical state, and the outer balloon in the second predetermined state is straight-tube shaped.

11. An dilatation balloon, comprising: an outer balloon and an inner balloon; the outer balloon is sleeved outside the inner balloon, and the inner balloon is filled with filling fluid to drive the outer balloon to expand; wherein the inner balloon has a first pre-shaped state during expansion; the material of the outer balloon is selected from PE, PET, PA or Pebax; the material of the inner balloon is selected from PE, PET, PA or Pebax.

12. An dilatation balloon, comprising: an outer balloon and an inner balloon; the outer balloon is sleeved outside the inner balloon; the inner balloon is configured to have a threshold condition during inflation with an inflation fluid for causing the inflation fluid therein to flow into the outer balloon when the inner balloon reaches the threshold condition.

13. The dilation balloon of claim 12, wherein the outer balloon is configured to have a first shape before the inner balloon is in the critical state and a second shape after the inner balloon is in the critical state, the first shape being defined by the inner balloon and being different from the second shape.

14. A balloon dilation catheter comprising a dilation balloon according to any one of claims 1to 13 and a catheter in communication with the proximal end of the inner balloon, the catheter being adapted to deliver an inflation fluid to drive the dilation or deflation of the dilation balloon.

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