JPH04144572A - Balloon and balloon catheter - Google Patents

Abstract

PURPOSE:To reduce the thickness of the balloon while sufficiently assuring the resilience, strength and durability of the balloon by constituting the balloon of a thin member having an inner layer consisting of crystalline plastic and an outer layer consisting of an elastic material having blood adaptability. CONSTITUTION:The balloon 3 is constituted of the thin member 30 laminated with the inside layer 31 and the outside layer 32. The inside layer 31 is a part to mainly bear the strength of the balloon 3 and is constituted of the crystalline plastic. Such crystalline plastic is, preferably, for example, polyethylene terephthalate and polyamide. The outside layer 32 is the part to mainly bear the resilience of the balloon 3 and is constituted of the elastic material having the blood adaptability. The elastic material having the blood adaptability is exemplified by various kinds of rubber, such as silicone rubber and latex rubber, and various kinds of thermoplastic elastomers, such as polyurethane, polyamide elastomer, polyester elastomer, polyethyene elastomer, and polyolefin elastomer.

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Application for Industrial Professionals> The present invention relates to a balloon used in a pallet catheter such as an intra-aortic balloon catheter used for assisting cardiac function, and a balloon.

<Conventional technology> In recent years, IABP (large tlJ intravenous balloon bombing)
The use of auxiliary circulation methods to treat cases of decreased left heart function due to acute myocardial infarction, etc., cases of impaired extracorporeal circulation, heart failure after cardiac surgery, and low cardiac output syndrome, etc., has gradually become popular. Conventional IABPs have generally been surgically inserted by exposing the blood vessel, but in recent years, IARPs that can be inserted percutaneously have been considered. ing. With the advent of IABPs that can be inserted percutaneously, IABPs can be inserted easily and quickly by people other than surgeons, such as internists and anesthesiologists, and there are also cases where IABPs are used prophylactically. It has become particularly popular in recent years.

However, while the application of IABP is expanding, problems of complications accompanying the use of IABP have also arisen. Complications that are becoming a problem include vascular complications, ischemic diseases, and organ failure, and their manifestations are not only caused by the patient, but also by the type of catheter, insertion method, and removal method. There are also things that seem to be caused by the medical side.

For such IABP balloon catheter-chill,
For example, there is one shown in US Pat. No. 4,327,709. This balloon catheter has a structure in which the proximal end of the balloon is fixed to the distal end of the catheter, and the distal end of the balloon is fixed to the distal end of a rigid wire passed through the inside of the catheter.

When inserting the balloon catheter, the balloon is deflated, wrapped around the wire, folded mA,
(wrapping).

This reduces the diameter of the balloon-attached portion, allowing percutaneous insertion using the Seldinger method or the like.

By the way, the balloon inserted into such an intra-aortic balloon catheter has flexibility, that is, so that an efficient blood supply function can be obtained by expanding and deflating the balloon.
A certain degree of compliance is required, and sufficient strength and durability are required to prevent the balloon from being damaged or bursting during insertion or bombing. Therefore, the balloon is composed of a thin member made of various types of polio I/fins, polyester, thermoplastic elastomer, etc., and its thickness is 130 mm in consideration of strength.
~150 μn or more are used.

However, with a balloon of such a height, wrapping is difficult, and when wrapping, the diameter of the balloon attachment part is reduced to an even smaller extent as shown in Figure 1-+.

do not have. For example, when inserting a balloon catheter percutaneously using a sheath using the Seldinger method, if the diameter of the balloon attachment part is large, a sheath with a large internal diameter must be used, but the diameter of the sheath is If the balloon size increases, complications such as lower limb ischemia are likely to occur, and the burden on the patient also increases.Furthermore, if the diameter of the balloon attachment area is too large.

Due to the inner diameter of the sheath, there is also a risk of damaging the balloon during insertion and withdrawal from the blood vessel.

In addition, some conventional balloons ('32) lack blood compatibility depending on their constituent materials, and blood clots may adhere to the balloons if they are inserted for a long period of time. 4 The attached thrombus will detach from the balloon due to the balloon's expansion and contraction actions, and this detached thrombus will cause lower limb ischemia and other complications.
Problems to be Solved by the Invention The present invention has been made in view of the problems of the prior art described above, and its purpose is to ensure sufficient flexibility, strength, and durability of the balloon while reducing its thickness. An object of the present invention is to provide a balloon and a balloon catheter that can be made thin and have excellent blood compatibility.

Means for Solving the Problems> Such objects are achieved by the following inventions (1) to (8).

(1) A thin-walled balloon whose internal volume can be expanded or contracted as driving fluid is injected or withdrawn, and which has at least an inner layer made of crystalline plastic and an outer layer made of an elastic material that is compatible with blood. A balloon characterized by comprising:

(2) The balloon according to (1) above, wherein the blood-compatible elastic material is an antithrombotic polymer having a microphase-separated structure.

(3) The balloon according to (2) above, wherein the antithrombotic polymer having a microphase-separated structure is segmented polyurethane or segmented polyamide.

(4) The balloon according to any one of (1) to (3) above, wherein the crystalline plastic has been subjected to a stretching process.

(5) The balloon according to any one of (1) to (4) above, wherein the thin member has a thickness of 30 to 100 μm.

(6) A balloon catheter comprising at least a tubular body having a lumen therein, and the balloon according to any one of (1) to (5) above communicating with the lumen.

(7) The balloon catheter has a core inserted into the lumen, the distal end of the balloon is fixed to the distal end of the core, and the proximal end of the balloon is
The balloon catheter according to (6) above, which is fixed to the distal end of the tubular body.

(8) The balloon catheter according to (7) above, wherein the core material is a tubular core material having a lumen inside.

<Function> In the present invention, since the balloon is composed of a thin member having at least an inner layer made of crystalline plastic and an outer layer made of a blood-compatible elastic material, its thickness can be made thinner than before. It has sufficient strength and flexibility (compliance) even when used, and also has excellent durability.

As a result, in a balloon catheter, particularly an intra-aortic balloon catheter, the balloon can be easily wrapped, and the outer diameter of the balloon attachment portion can be reduced when wrapped.

Since the outer diameter of the balloon attachment portion is reduced, percutaneous insertion of the balloon catheter becomes easier, and the inner diameter of the sheath, which is the insertion instrument, can be reduced.

As a result, the burden on the patient is reduced, and ischemia caused by the inner diameter of the sheath is prevented, thereby suppressing the occurrence of complications.

In addition, since the outer layer of the balloon is made of an elastic material that is compatible with blood and has antithrombotic properties, blood clots will not adhere to the balloon even when used continuously for a long period of time. This prevents ischemia caused by blood clots that have dislodged from blood vessels, thereby suppressing the occurrence of complications.

<Configuration of the Invention> The balloon and balloon catheter of the present invention will now be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 is a partial vertical cross-sectional view showing an example of the configuration when the balloon catheter of the present invention is applied to an intra-aortic balloon catheter.

As shown in the figure, an intra-aortic balloon catheter l (hereinafter also simply referred to as a balloon catheter) has a tubular body 2,
It is composed of a balloon 3, a core material 4, and a branched cane 10 of the present invention.

Specifically, the balloon catheter 1 having the configuration shown in FIG. G;1. A tubular hub 6 is fixed to the base fjA of the core 4, and a core hub 7 is fixed to the base fjA of the core 4. The tubular hub 6 and the core hub 7 constitute a branch hub 10. .

Further, a tip part 5 is marked at the tip of the core material 4, and the tip part of the balloon 3 is fixed to this tip member 5.
7, the proximal end of the pallet 3 is firmly attached to the distal end of the tubular body 2).

It is preferable that the tubular body 2 has a certain degree of flexibility, and its composition may include materials such as polyurethane, tyrene, polypropylene copolymer, non-propylene copolymer, etc. Polyolefins such as Eglen-vinyl acetate copolymer, polyvinyl chloride, polyamide elastomer 7
・-, thermoplastic resins such as polyurethane, silicone rubber, latex swim, etc.A'1. Ru. Among these, the thermoplastic resins listed in "2" are preferred, and polyolefins are more preferred.

As the core 244, stainless steel (preferably 1, imaginary, high tension stainless steel for springs), piano wire (preferably,
Examples include nickel plated, piano cotton with chrome plating), and superelastic alloy.

As for superelastic alloys, 49=, 58 atoms 9≦Ni alloy, 38.5-41.5 Jukei 96Z
n (7) Cu-Zn alloy, 1-io heavy rice %X Cu-Zn-X alloy (n(=Be, *'31% S
n LΔβ, G a) , 36””3 g atom% AI2
A superelastic gold body such as N1-A72 alloy is preferably used.Among these, particularly preferred are T
It is an i-Ni alloy.

3. The part of the core material 4 that protrudes from the tip of the tubular body 2 (hereinafter referred to as the protruding part) has a core! , 14, for the purpose of preventing folding, bending, etc., a reinforcing member (shown in the figure (4)) may be provided. As this reinforcing member, for example, a material wrapped spirally around the outer periphery of the core material 4, etc. As the constituent material of the tube, the above-mentioned metal material having contrast properties is suitably used. A tip member 51i fixed to the tip of the core material 4 functions as a guiding part of the balloon catheter chill 1, In addition, the distal end of the balloon catheter 1 is designed to prevent damage to the blood vessel wall during insertion into the blood vessel.

Therefore, the tip of the tip member 5 has a bullet-like, hemispherical shape, and a curved surface.

The constituent material of the tip member 5 is preferably one having a certain degree of flexibility, such as polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-propylene copolymer, etc.
Examples include thermoplastic resins such as poly-1-nophine such as vinyl acetate copolymer, polyvinyl chloride, polyamide colastomer, polyurethane, silicone rubber, latex rubber, etc. 8 Among them, Queen's thermoplastic resin is preferred L5 It is preferable that the tip end +A5 is (7) attached to the pallet 3, which will be described later.

U-, f, Z, tip +15 are balloon catheter 1
Since it is also the distal end of the tube, it is preferable that its position can be easily confirmed under x-is fluoroscopy.

Inside the tip member 5, there is a P treasure or Pl.
- based alloy, W or W based alloy, Ag or U.

It is also possible to embed metal parts using Ag-based alloys or mix in excess pressure powder.

The balloon 3 of the present invention is capable of expanding (expanding) and contracting (deflating) its internal volume according to changes in internal pressure. (configuration example shown in the figure) or cylindrical with both ends open (configuration example shown in Figure 2).

This pallet 3 is arranged to cover the outer periphery of the protruding portion of the core material 4. When the Pal-N catheter 1 is inserted into a blood vessel, the balloon 3 is deflated so that it is wrapped around the outer periphery of the core material 4 (wrapping).

That is, the distal end of the balloon 3 is fixed to the distal end member 5 fixed to the distal end of the core material 4, for example, by adhesion or fusion, and the proximal end of the balloon 3 is fixed to the distal end of the tubular body 2. For example, it is fixed by adhesive or fusion.

Further, the inside of the balloon 3 communicates with a lumen 9 formed inside the tubular body 2 through the tip opening of the tubular body 2, and a driving fluid is injected into the inside of the balloon 3 through the lumen 9. Alternatively, the driving fluid can be removed from the inside of the balloon 3.

As the driving fluid is injected and withdrawn, the balloon 3 inserted into a predetermined position within the aorta expands and contracts, allowing blood to be pumped out in a pulsating manner.

The driving fluid may be a gas or a liquid (eg, a gas that easily dissolves in blood such as helium gas, CO4 gas, 0□ gas, etc., or a liquid such as physiological saline).

Note that the configuration, dimensions, etc. of the balloon 3 itself will be described in detail later.

The branch hub IO is composed of a tubular hub 6 and a core hub 7. The tubular body hub 6 is air-tightly or liquid-tightly fixed to the proximal end of the tubular body 2, and has an opening 8 that communicates with the lumen 9 of the tubular body 2. It functions as an inlet and an outlet for the driving fluid that causes expansion and contraction.

Examples of the material for the tubular hub 6 include thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer.

Further, the core material hub 7 is fixed to the base end of the core material 4 in an air-tight or liquid-tight manner. Then, the core material hub 7 and the tubular body hub 6
Although the core material hub 7 may be fixed to the core material hub 7, the core material hub 7 may be configured to be rotatable while maintaining an airtight or liquid-tight state between the two. In this case, by rotating the core material hub 7, the core material 4 also rotates accordingly, making it possible to easily wrap the balloon 3 around the outer periphery of the core material 4 during wrapping.

FIG. 2 is a partial longitudinal sectional view showing another example of the structure of the intra-aortic balloon catheter of the present invention. The balloon catheter 1 shown in the figure has a core material with a lumen inside.
The tubular core material 40 has a diameter of 1. This lumen 11 is open on the distal side and can be used as (1) a passage for passing a guide wire, (2) a flow path for administering a necessary drug, or (2) a measurement of aortic pressure.

The tubular core material 40 preferably has a certain degree of flexibility, such as polyethylene, polypropylene,
Polyolefins such as ethylene-propylene copolymers, ethylene-vinyl acetate copolymers, polyvinyl chloride,
Examples include those made of polyamide, polyimide, polyvinylidene fluoride, ethylene-polytetrafluoroethylene copolymer, thermoplastic resin such as polyurethane, silicone rubber, latex rubber, and the like.

Further, as the tubular core material 40, a metal tubular body may be used, and as the metal tubular body, a stainless steel tubular body, a superelastic alloy tubular body, etc. are suitable. In particular, a superelastic alloy tubular body is suitable.

Ti-Ni alloy with 49-58 atomic % Ni.

Cu-Zn alloy with 38.5-41.5 wt% Zn, l~
Cu-Zn-X alloy with lO wt%X (X=Be, SL%
Sn, AI2, Ga), 36-38 at% N1- at A°C
A superelastic metal body such as A2 alloy is preferably used. Among these, the above Ti-Ni alloy is particularly preferred.

Further, as described above, a reinforcing member may be provided on the protruding portion of the tubular core material 4.

The branch hub 10 is composed of a tubular body hub 6 and a tubular core hub 13.

A tubular core hub 13 is fixed to the rear end of the tubular core 40, and an opening l2 communicating with the lumen 11 inside the tubular core 40 is provided at the rear end. The tubular core material hub 13 and the tubular body hub 6 may be fixed to each other, but the tubular core material hub 13 may be configured to be rotatable as described above. In such a case, by rotating the tubular core material hub 13, the tubular core material 4 will follow and rotate, so the balloon 3 can be easily wrapped around the outer periphery of the tubular core material 4 during wrapping. , 83 is possible, this J: Una Balloon Catheter 1 and 1.

Preferred dimensions of various parts of the holder are as shown in Table 1 below.

In the table, the number 64 in parentheses indicates a more preferable range.
The configuration of Part 3 will be explained below.

FIG. 3 is an enlarged vertical cross-sectional view showing the configuration of the balloon 3. FIG. As shown in the figure, the balloon 3 has an inner 1113
1 and an outer layer 32 are laminated together.

The inner part 1!131 is a part mainly responsible for the strength of the balloon 3, and is made of crystalline plastic. here,
Crystalline plastic refers to plastic that can be crystallized and has a degree of crystallinity of 0.2 to 1.

The degree of crystallinity of a crystalline plastic can be measured by, for example, an X-ray method, a density method, an infrared method, a nuclear magnetic co-absorption method, or the like.

The reason why crystalline plastic is used for the inner jl 131 is that if the crystalline plastic is subjected to stretching processing, it is possible to obtain a high-strength and thin ridge opening 31.

Therefore, although the crystalline plastic materials described below may be used as they are, they are preferably used after being subjected to stretching processing (for example, stretch blow molding).

Examples of such crystalline plastics include polyethylene nonte[nophthalate (PET).

Crystalline polyesters, polyamides such as polybutylene (PBT), polyethylene and copolymers thereof.

Examples include polyethylene, polypropylene, etc., and among these, PET and polyamide are particularly preferred.

The outer layer 32 is a portion mainly responsible for the flexibility of the balloon 3, and is made of an elastic material that allows blood to flow. Here, an elastic material that has blood association properties means that when it comes into contact with blood, either by the material itself or by the addition of additives,
Use old elastic materials that make it difficult for platelets and substance to adhere to them. Therefore, if such a material is used for the outer layer 32, blood coagulation may occur and contact with blood vessels may occur. 2
．． Unfortunately, the intima of the blood vessel was damaged.

Examples of elastic materials having blood compatibility include various rubbers such as silicone rubber and latex rubber, and various thermoplastic elastomers such as polyurethane, polyamide elastomer, polyester elastomer, polystyrene elastomer, and polyolefin elastomer.

Furthermore, an antithrombotic drug such as heparin, prostaglandin, urokinase, or arginine derivative may be blended into such an elastic material to provide a material having antithrombotic properties.

Further, among elastic materials having blood compatibility, an antithrombotic polymer having a microphase-separated structure when observed by electron microscopy as a material having antithrombotic properties itself may be used.

Examples of antithrombotic polymers having this microphase-separated structure include urethane systems such as segmented polyurethane and fluorine-containing segmented polyurethane, and segmented polyamides (Japanese Patent Application No. 01-314924, Japanese Patent Application No. 02-02-
Various block copolymers such as amide type such as 74357), ester type such as polyhydroxyethyl methacrylate-polystyrene block copolymer, and polyether-polyester block copolymer can be mentioned. Among these, urethane-based, amide-based, or styrene-based materials are particularly preferred in terms of fatigue resistance, appropriate flexibility, high antithrombotic properties, and more preferably segmented polyurethane or segmented polyamide. When such a material is used, the microphase-separated structure formed on the surface of the outer layer 32 exhibits excellent antithrombotic properties (especially inhibition of platelet adhesion).

For reference, the physical properties of the segmented polyurethane are shown in Table 2 below.

As shown above, since the outer layer 32 of the balloon 3 is made of an elastic material having blood compatibility, especially antithrombotic properties,
Even when the balloon is used continuously for a long period of time, the attachment of blood clots to the balloon is prevented. Furthermore, since the outer layer 32 is made of an elastic material, there is no risk of damaging the inner wall of the blood vessel.

The balloon 3 of the present invention combines the inner layer 31 made of crystalline plastic and the outer layer 32 made of an elastic material compatible with blood, so that the balloon 3 has both strength, durability, and flexibility. Therefore, the thickness of the thin member 30 can be made thinner than that of conventional balloons.

Preferred dimensions of various parts of the balloon 3 used in such an intra-aortic balloon catheter are shown in Table 3 below.

Table 3 In the table, the numbers in parentheses indicate the more preferred range of such balloons from il' to 1,7 to 1. evening,
For example, the following can be torn off. J: First, the inner layer 31 is formed by, for example, stretching and molding, and then the melt of the constituent material of the outer layer 32 or the constituent material is applied to the outer surface of the inner layer 31. The outer layer 32 is formed by applying a solution of 1, spraying, wiping, etc., and then drying this.

(2) The inner layer 31 and outer layer 32 are integrally molded by two-color molding or ingert molding.

■ Inner layer 31, outer layer 32, and 2r gouyu in advance.
After molding, this 1. In this way, the balloon of the present invention can be easily manufactured by blow molding while stretching it in the length direction and molding it integrally. When dipping the solution of the balloon's constituent material, no wax is needed for a mold (the inner layer 31 manufactured first functions as a mold); This eliminates the need for melting wax, making it possible to simplify the manufacturing process and reduce costs.

The balloon in the present invention may have at least 1.2"r of the inner layer and the outer layer. , one having an innermost layer inside the inner layer 31 (none of which is shown), etc., a laminate of three polishing tools 1- including the inner layer 31 and the outer layer 32 may be used. .

In the example shown in Figures 1 and 2, the outer diameter of the balloon 3 when the balloon is inflated is approximately constant along the longitudinal direction of the balloon. 1
However, the maximum outer diameter of the balloon when inflated is near the longitudinal center of the balloon, the maximum outer diameter of the balloon when inflated is closer to the tip than the longitudinal center of the balloon, and The maximum outer diameter portion of the Id balloon when inflated may be located closer to the proximal end than the longitudinal center of the balloon.

In this case, if a balloon is used whose outermost diameter part when inflated is on the distal or proximal side of the longitudinal center of the balloon, blood can be more reliably delivered to the peripheral or central side, respectively. This has the advantage of reliably exerting the auxiliary circulation effect.

Note that the balloon and balloon catheter of the present invention include:
Not limited to those used as the above-mentioned intra-aortic balloon catheters, for example, PTCA balloon catheters,
It can also be used as a balloon and a balloon catheter for vascular endoscopy, various monitoring catheters/chills, balloon catheters for thrombus removal, etc. Furthermore, the configuration of the balloon expansion/chill structure of the present invention is limited to that shown in the drawings. Needless to say, it won't happen.

<Effects of the Invention> As described above, according to the present invention, the flexibility, strength, and durability of the balloon can be sufficiently ensured, and the thickness of the balloon can be reduced in terms of I and 2. can.

As a result, when the present invention is applied to an intra-aortic balloon catheter, the balloon can be easily wrapped, and the outer diameter of the portion to which the balloon is attached can be reduced when wrapped. Also, since the outer diameter of the part where the balloon is attached becomes smaller, the balloon
Percutaneous insertion of the catheter becomes easier, and the diameter of the sheath, which is the insertion device, can be reduced, which reduces the burden on the patient and prevents ischemia, etc. This caused complications! 1. suppress.

In addition, since the outer layer of the balloon is made of an elastic material that is anti-thrombotic and particularly anti-thrombotic, there is no possibility of blood clots adhering to the balloon even when used continuously for a long period of time. This prevents ischemia caused by blood clots detached from the balloon, thereby reducing the risk of complications.

[Brief explanation of the drawing]

FIG. 1 is a partial longitudinal sectional view showing an example of the configuration of a balloon catheter of the present invention. FIG. 2 is a partial longitudinal sectional view showing another example of the configuration of the balloon catheter of the present invention. FIG. 3 is an enlarged longitudinal sectional view showing the configuration of the balloon of the present invention. Explanation of symbols 1.1' Balloon catheter 2 Tubular body 3 Balloon 30 Thin member 31 Inner layer 32 Outer layer 4 Core material 40 Tubular Core material 5...Tip member 6...Tubular body hub 7...Core material hub 8...Opening 9...Lumen 10...Branch hub 11...Lumen 12...Opening 13...Tubular core hub

Claims (8)

[Claims] (1) A thin-walled balloon whose internal volume can be expanded or contracted as driving fluid is injected or withdrawn, and which has at least an inner layer made of crystalline plastic and an outer layer made of an elastic material that is compatible with blood. A balloon characterized by comprising: (2) The balloon according to claim 1, wherein the blood-compatible elastic material is an antithrombotic polymer having a microphase-separated structure. (3) The balloon according to claim 2, wherein the antithrombotic polymer having a microphase-separated structure is segmented polyurethane or segmented polyamide. (4) The balloon according to any one of claims 1 to 3, wherein the crystalline plastic has been subjected to a stretching process. (5) The balloon according to any one of claims 1 to 4, wherein the thin member has a thickness of 30 to 100 μm. (6) A balloon catheter comprising at least a tubular body having a lumen therein and the balloon according to any one of claims 1 to 5 communicating with the lumen. (7) The balloon catheter has a core inserted into the lumen, the distal end of the balloon is fixed to the distal end of the core, and the proximal end of the balloon is
The balloon catheter according to claim 6, wherein the balloon catheter is fixed to a distal end portion of the tubular body. (8) The balloon catheter according to claim 7, wherein the core material is a tubular core material having a lumen inside.