JPH06165821A - Balloon catheter - Google Patents

Abstract

PURPOSE:To expand and contract a balloon part with good responsiveness by decreasing the flow passage resistance in a catheter pipe in which pressurized fluid passes without increasing a patient's burden. CONSTITUTION:This balloon catheter has a balloon part 22 which is inserted into the aorta and expands and contracts to effect the assistance effect of the cardiac function, the catheter pipe 24 which leads the pressurized fluid into and out of the balloon part 22, a blood stopping plug 40 which is freely axially movably mounted to the outer periphery at the rear end of the catheter pipe 24 and has a blood stopping sheath part 42 which closes an insertion port formed in the patient's blood vessel and a connector 26 which is connected with the end part of the catherter pipe 24 and is formed with a pressurized fluid introducing/discharging port 28 for introducing and discharging the pressurized fluid to the balloon part 22. The outside diameter of the catheter pipe 24 from the blood stopping plug 40 to the connector 26 is increased by 3 to 30% as compared with the diameter in the other parts. The pressurized fluid introducing/discharging port formed at the connector is disposed to a straight shape along the axial center direction of the catheter pipe.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a balloon catheter used for intra-aortic balloon pumping, which is a method for treating acute heart failure and the like.

[0002]

2. Description of the Related Art Aortic balloon pumping method (Intra
Aortic balloon pumping (hereinafter, abbreviated as “IABP method”) is used for treatment when heart function declines such as heart failure.
As shown in FIG. 2, a balloon catheter 2 made of a synthetic polymer material is inserted into the aorta, and a pump device 8 introduces or draws out a pressure fluid from the catheter tube 6 to the balloon portion 4 in accordance with the pulsation of the heart 1. This is an auxiliary circulation method of expanding and contracting the portion 4 to assist the heart function.

As balloon catheters used in the IABP method, balloon catheters as disclosed in JP-A-63-206255 and JP-A-62-114565 are known. In such a balloon catheter, it is necessary to detect the pulsation of the patient's heart in order to expand and contract the balloon portion according to the pulsation of the heart. As a means for detecting the pulsation of the heart of a patient, there is a means for mounting an electrode on the body surface or inside the patient and detecting the pulsation of the heart as an electric signal.

As a means for detecting a heartbeat from the blood pressure of a patient using a balloon catheter, a blood communication hole is provided in the tip 12 of the balloon portion 4 shown in FIG. 3 and communicated with the blood communication hole. There is a method of detecting the heartbeat by inserting the inner tube 10 into the balloon portion 4 and the catheter tube 6 in the axial direction and measuring the blood pressure fluctuation from the blood communication hole 5.

In order to insert such a balloon catheter 2 into an arterial blood vessel of a patient, a thin film forming the balloon portion 4 is wrapped around the inner tube 10 so that the diameter is about the same as or smaller than that of the catheter tube 6, and the tip thereof is cannulated. Is used to insert into the aorta of the leg, and then from there into the artery near the heart 1 until the balloon portion 4 reaches.

[0006]

However, such a balloon catheter 2 has the following problems. That is, since the catheter tube 6 is inserted into the arterial blood vessel of the patient, it is preferable that the outer diameter is smaller in consideration of the burden on the patient. However, when the outer diameter of the catheter tube 6 is small, the flow path of the pressure fluid formed inside the catheter tube 6 becomes small, the flow path resistance increases, and the timing response of the expansion / contraction of the balloon portion 4 driven by the pressure fluid. There is a risk that the sex will deteriorate and the assisting action of the heart will not be able to be exerted effectively. The inflation / deflation cycle of the balloon portion 4 is a short cycle of about 0.6 sec, and the pressure fluid reciprocates within the catheter tube 6 during this short cycle, so the smaller the flow path resistance, the better.

Therefore, conventionally, the outer diameter of the catheter tube is
The size of the balloon 4 is set as large as possible within a range that does not significantly increase the burden on the patient, and the outer diameter of the balloon 4 is fixed in the axial direction to sacrifice the inflation / deflation timing responsiveness of the balloon portion 4 to some extent.

The present invention has been made in view of the above circumstances, and reduces the flow path resistance in the catheter tube through which the pressure fluid passes and inflates / deflates the balloon portion with good responsiveness without increasing the burden on the patient. It is an object of the present invention to provide a balloon catheter capable of

[0009]

In order to achieve the above object, a balloon catheter of the present invention is inserted into an aorta, and expands and contracts so as to assist the function of the heart. A catheter tube connected to the rear end of the catheter tube for introducing and drawing out a pressure fluid into the balloon portion, and an axially movable attachment to the outer periphery of the rear end side of the catheter tube, to an insertion port formed in a blood vessel of a patient. A hemostatic plug having a hemostatic sheath portion that closes the insertion port of the blood vessel by pushing in the distal end is connected to the rear end portion of the catheter tube to form a pressure fluid inlet / outlet for introducing / discharging pressure fluid to / from the balloon portion. A balloon catheter having a connector, wherein the outer diameter of the catheter tube from the hemostatic plug to the connector is increased from the balloon portion to the hemostatic plug. To the outer diameter of the catheter tube, 3-3
It is characterized by being thickened by 0%.

In the connector, a blood pressure measuring port for measuring the blood pressure of blood taken through the inner tube from the blood communicating port provided at the tip of the balloon is formed separately from the pressure fluid introducing port. The pressure fluid inlet / outlet may be arranged straight along the axial direction of the catheter tube, and the blood pressure measurement port may be disposed with a predetermined inclination with respect to the axial center of the pressure fluid inlet / outlet. preferable.

[0011]

In the balloon catheter of the present invention, the outer diameter of the catheter tube is not made constant in the axial direction, but the outer diameter of the catheter tube from the hemostatic plug, which is a portion located outside the blood vessel of the patient, to the connector is set to the patient. For the outer diameter of the catheter tube from the balloon located in the blood vessel of the to the hemostatic plug,
It is thickened by 3 to 30%. The percentage range is 3%
In the following cases, the effect of the present invention is small, and when it is 30% or more, the outer diameter of the hemostatic sheath portion becomes too large, which makes it difficult to insert it into the skin tissue of the patient and makes molding difficult. This is because it is not preferable.

By increasing the outer diameter of the catheter tube from the hemostatic plug to the connector in such a range, if the wall thickness of the catheter tube is the same in the axial direction, the inner diameter of the catheter tube from the hemostatic plug to the connector is also increased. Getting bigger,
The flow path cross section at that portion also becomes large. As a result, the flow path resistance inside the catheter tube can be reduced without increasing the burden on the patient. Since the length of the catheter tube from the hemostatic plug to the connector corresponds to about 20 to 35% of the total length of the catheter tube, increasing the outer diameter of this portion increases the cross section of the flow channel. It is very effective in reducing the internal flow path resistance of the entire catheter tube. The flow path resistance (pressure loss) is determined by the fourth power of the inner diameter of the catheter tube. If the inner diameter is increased by 3 to 30%, the flow resistance can be reduced by (3 to 30) to the fourth power, and the reduced area is the entire length. Since it is 5 to 35%, it is expected that the flow path resistance of the entire inside of the catheter tube will be improved by 10% or more.
Also, in terms of responsiveness of inflation and deflation of the balloon part,
% Improvement can be expected.

Further, according to the present invention, in which the pressure fluid inlet / outlet is arranged straight along the axial direction of the catheter tube,
Compared to the conventional example in which the blood pressure measurement port is arranged straight along the axial direction of the catheter tube, the flow resistance of the pressure fluid is expected to improve by 2% and from the viewpoint of responsiveness, improve by 4%. it can.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A balloon catheter according to an embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a main part of a balloon catheter according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view of a main part of a balloon catheter according to another embodiment of the present invention.

As shown in FIG. 1, a balloon catheter 20 according to an embodiment of the present invention has a balloon portion 22 that expands and contracts in accordance with the pulsation of the heart. The balloon portion 22 is composed of a thin film having a film thickness of about 100 to 150 μm. The material of the thin film is not particularly limited, but is preferably a material having excellent bending fatigue resistance, and is composed of, for example, polyurethane. The outer diameter and the length of the balloon portion 22 are determined according to the inner volume of the balloon portion 22, which greatly affects the assisting effect of the cardiac function, the inner diameter of the arterial blood vessel, and the like. The inner volume of the balloon portion 22 is not particularly limited, but is 30 to 50 cc, and the outer diameter of the balloon portion 22 is
14 to 16 mm is preferable, and the length is 210 to 270 m
m is preferred.

A tip portion 25 having a blood communicating hole 23 formed therein is attached to the tip portion of the balloon portion 22 by means such as heat fusion or adhesion. The tip portion of the inner tube 30 is attached to the inner peripheral side of the tip portion 25 by means such as heat fusion or adhesion.

The inner tube 30 extends in the axial direction inside the balloon portion 22 and the catheter tube 24 and communicates with a blood pressure measurement port 32 of a connector 26, which will be described later. It does not communicate with the inside. The inner tube 30 located in the balloon portion 22 serves as a guide rod when the deflated balloon portion 22 is wound and the balloon portion 22 is conveniently inserted into the artery when the balloon catheter 20 is inserted into the artery. It also has an effect.

The distal end of the catheter tube 24 is connected to the rear end of the balloon portion 22 on the outer peripheral side of the metallic connecting tube 27. Through this catheter tube 24, a fluid pressure is introduced into or drawn out from the balloon portion 22, and the balloon portion 22 is inflated or deflated. The balloon portion 22 and the catheter tube 24 are connected by heat fusion or adhesion with an adhesive such as an ultraviolet curable resin.

The material forming the catheter tube 24 is not particularly limited, but polyurethane, polyvinyl chloride, polyethylene, nylon, etc. are used. A connector 26, which is installed outside the patient's body, is connected to the rear end of the catheter tube 24. The connector 26 may be molded separately from the catheter tube 24 and fixed by means such as heat fusion or adhesion, or may be molded integrally with the catheter tube 24. The connector 26 is formed with a pressure fluid inlet / outlet 28 for introducing or discharging a pressure fluid into the catheter tube 24 and the balloon portion 22, and a blood pressure measurement port 32 communicating with the inside of the inner tube 30.

The pressure fluid inlet / outlet 28 is connected to a pump device 8 as shown in FIG.
The fluid pressure is introduced or discharged into the balloon portion 22. The fluid to be introduced is not particularly limited, but helium gas or the like having a low viscosity is used so that the balloon portion quickly expands or contracts in response to the driving of the pump device 8. The pump device 8 is not particularly limited, and for example, a device disclosed in Japanese Patent Publication No. 2-39265 can be used.

The blood pressure measuring port 32 is connected to, for example, a blood pressure measuring device, and is capable of measuring fluctuations in blood pressure of blood in the artery taken from the blood communication hole 23. Based on the blood pressure fluctuation measured by this blood pressure measuring device, the heart beat is detected, and the pump device 8 as shown in FIG. 3 is detected according to the heart beat.
Is controlled to inflate or deflate the balloon portion 22.

In this embodiment, a hemostatic plug 40 is attached to the outer circumference of the catheter tube 24 located in front of the connector 26 so as to be movable along the axial direction of the catheter tube 24. The hemostatic plug 40 has a hemostatic sheath portion 42 that closes the insertion port of the blood vessel by pushing the tip 42a into the catheter insertion port formed in the blood vessel of the patient when the balloon catheter is inserted, and is located outside the blood vessel of the patient. To do. The rear end portion of the hemostatic sheath portion 42 is connected to the handle base portion 46 via the sheath base end portion 44. On the outer periphery of the handle base portion 46, a handle 47 is formed to project and a male screw portion 49 is formed.

The female screw portion 51 of the cap portion 50 can be screwed into the male screw portion 49 of the handle base portion 46.
An elastic fixing ring 48 is interposed between the handle base portion 46 and the cap portion 50, and the female screw portion 51 of the cap portion 50 is fastened to the male screw portion 49 of the handle base portion 46. If inserted, the fixing ring 48 will elastically deform,
The inner diameter of the catheter tube 24 becomes small, and the catheter tube 24 is pressed against the outer circumference of the catheter tube 24 to fix the entire hemostatic plug 40 to the outer circumference of the catheter tube 24 and regulate the axial movement.

In a state where the female screw portion 51 of the cap portion 50 is not tightened with respect to the male screw portion 49 of the handle base portion 46, the inner diameter of the fixing ring 48 is larger than the outer diameter of the catheter tube 24, and the hemostatic plug is provided. The entire 40 is axially movable with respect to the catheter tube 24. Hemostatic plug 40
As described above, the distal end 42a of the hemostatic sheath portion 42 is pushed into the catheter insertion opening formed in the blood vessel of the patient and has an action of closing the insertion opening of the blood vessel, but the catheter insertion opening formed in the blood vessel of the patient. Since the relationship between the catheter tube 24 and the axial position of the catheter tube 24 differs depending on the patient, the hemostatic sheath portion 42 moves axially with respect to the catheter tube 24 together with the hemostatic plug 40, and the catheter tube 24 is moved at a predetermined axial position. Need to be fixed against.

In this embodiment, the outer diameter of the catheter tube 24 is not made constant in the axial direction, and the hemostatic plug 40 is connected to the connector 26.
The outer diameter of the catheter tube 24 within the range of the length L reaching the catheter tube 2 from the balloon portion 22 to the hemostatic plug 40.
The outer diameter of 4 is thicker by 3 to 30%. this%
The range is set so that the effect of the present invention is small when it is 3% or less, and the outer diameter of the hemostatic sheath portion 42 becomes too large when it is 30% or more, and it is difficult to insert it into the skin tissue of the patient. In addition, it is not preferable because the molding becomes difficult.

The outer diameter of the catheter tube 24 from the balloon portion 22 to the hemostatic plug 40 is generally 2.3 to 4.0.
Since it is mm, the outer diameter of the catheter tube 24 within the range of the length L from the hemostatic plug 40 to the connector 26 is 2.4 to
About 5.2 mm is preferable. The thickness of the catheter tube 24 is
It is preferably uniform in the axial direction, and is 0.05 to 0.4.
mm is preferable.

The length L from the hemostatic plug 40 to the connector 26 is not particularly limited, but is preferably about 100 to 200 mm, which is about 5 to 35% of the total length of the catheter tube 24.

In the balloon catheter 20 of this embodiment,
Catheter tube 2 from the hemostatic plug 40 to the connector 26
By making the outer diameter of 4 larger than that of the other portion by 3 to 30%, if the wall thickness of the catheter tube 24 is the same in the axial direction, the inner diameter of the catheter tube 24 from the hemostatic plug 40 to the connector 26 is also increased. It becomes 3 to 30% larger, and the flow passage cross section at that portion also becomes larger. As a result, the flow path resistance inside the catheter tube 24 can be reduced without increasing the burden on the patient.

The length L of the catheter tube from the hemostatic plug 40 to the connector 26 corresponds to about 20 to 35% of the total length of the catheter tube 24. Therefore, by increasing the outer diameter of this portion, the flow path is increased. Increasing the cross section has a great effect in reducing the internal flow path resistance of the entire catheter tube 24. The flow path resistance is determined by the cube of the inner diameter of the catheter tube 24. If the inner diameter is increased by 3 to 30%, the flow path resistance can be reduced by (3 to 30) to the fourth power%, and the reduced area is 5 to 5% of the total length. Since it is 35%, the flow path resistance of the entire inside of the catheter tube 24 can be expected to be improved by 10% or more.
Also, in terms of the responsiveness of inflation / deflation of the balloon portion 22,
An improvement of 20% or more can be expected.

The catheter tube 24 having a large diameter is formed.
The outer diameter of the sheath portion 42 located on the outer periphery of the
Since the sheath portion 42 is not inserted into the blood vessel of the patient and only a part of the distal end side is inserted into the skin tissue in front of the blood vessel of the patient, the burden on the patient is not so large.

The present invention is not limited to the above-mentioned embodiments, but can be variously modified within the scope of the present invention. For example, as shown in FIG.
The pressure fluid introduction outlet 28a formed in 6a is arranged in a straight line along the axial direction of the catheter tube 24, and the blood pressure measurement port 32a is arranged with a predetermined inclination with respect to the axis of the pressure fluid introduction outlet 28a. It can also be configured as follows. In the case of this embodiment, compared with the embodiment shown in FIG. 1 in which the blood pressure measurement port 32 is arranged straight along the axial direction of the catheter tube 24, the flow resistance of the pressure fluid is further 2%. From the viewpoint of improvement and responsiveness, further improvement of 4% can be expected. This is because the flow resistance in the pipe flow is smaller in the straight flow than in the curved flow.

In the present invention, the use of the inner tube 30 is not limited to blood pressure measurement, but may be used for other purposes. Further, in the present invention, the inner tube 30 is not always necessary and may be a simple support rod. In that case, it is necessary to use other means for detecting the heartbeat or the blood pressure fluctuation cycle.

[0033]

As described above, according to the present invention, the flow path resistance inside the catheter tube can be reduced without increasing the burden on the patient. Since the length of the catheter tube from the hemostatic plug to the connector corresponds to about 20 to 35% of the total length of the catheter tube, increasing the outer diameter of this portion can increase the cross section of the flow channel. It is very effective in reducing the internal flow path resistance of the entire catheter tube. Since the flow path resistance is obtained by the fourth power of the inner diameter of the catheter tube, the flow path resistance of the entire inside of the catheter tube can be expected to be improved by 10% or more. Also, in terms of the response of balloon inflation / deflation, 20%
The above improvements can be expected. In the present invention in which the pressure fluid inlet / outlet is arranged straight along the axial direction of the catheter tube, the blood pressure measurement port is compared with the conventional example in which the blood pressure measurement port is arranged straight along the axial direction of the catheter tube. 2% improvement in fluid flow resistance, 4% from the viewpoint of responsiveness
Can be expected to improve. Therefore, in the present invention, the responsiveness of the balloon portion is improved, the balloon portion is inflated and deflated at a good timing, and the assisting effect of the cardiac function is improved without increasing the burden on the patient.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a main part of a balloon catheter according to an embodiment of the present invention.

FIG. 2 is a schematic sectional view of a main part of a balloon catheter according to another embodiment of the present invention.

FIG. 3 is a cross-sectional view showing a usage state of a balloon catheter.

[Explanation of symbols]

 20 ... Balloon catheter 22 ... Balloon part 23 ... Blood introduction port 24 ... Catheter tube 25 ... Tip part 26 ... Connector 28 ... Pressure fluid introduction outlet 30 ... Inner tube 32 ... Blood pressure measurement port 40 ... Hemostasis plug 42 ... Hemostasis sheath part 42a … Tip

Claims (2)

[Claims] 1. A balloon part that is inserted into an aorta and expands and contracts so as to assist the function of a heart function; and a balloon part that is connected to a rear end of the balloon part and introduces and draws a pressure fluid into the balloon part. A hemostatic plug having a catheter tube and a hemostatic sheath portion that is axially movably attached to the outer circumference of the rear end side of the catheter tube and that closes the insertion port of the blood vessel by pushing the tip into the insertion port formed in the blood vessel of the patient. And a connector in which a rear end portion of the catheter tube is connected and a pressure fluid introduction / extraction port for introducing / discharging a pressure fluid to / from the balloon portion is formed, the balloon catheter extending from the hemostatic plug to the connector. The balloon which is characterized in that the outer diameter of the catheter tube is 3 to 30% larger than the outer diameter of the catheter tube from the balloon portion to the hemostatic plug. Catheter. 2. A blood pressure measurement port for measuring the blood pressure of blood taken in through an inner tube from a blood communication port provided at the distal end of the balloon portion of the connector, separately from the pressure fluid introduction / outlet port. The pressure fluid introduction outlet is arranged in a straight line along the axial direction of the catheter tube, and the blood pressure measurement port is arranged with a predetermined inclination with respect to the axial center of the pressure fluid introduction outlet. The balloon catheter according to claim 1, wherein the balloon catheter is a balloon catheter.