JP2510428B2 - Balloon catheter - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vascular dilatation balloon catheter for treating stenosis of blood vessels due to arteriosclerosis and the like.

[0002]

2. Description of the Related Art As a method of treating a stenosis of a blood vessel with a balloon catheter, the balloon catheter is pressurized and expanded, and at the same time a high frequency current (voltage) is applied from the inside of the balloon.
A method of irradiating a laser beam or a laser beam to heat the hardened part is already under development and experiment. A method using a high frequency current, that is, a dielectric heating method, is a patent application of the present inventor (Japanese Patent Application No. 2-5036).
No. 1).

[0003]

In the above-mentioned prior art, since the balloon itself is warmed by the laser beam or the high frequency current (voltage) and the heat is diffused from the inner wall of the blood vessel to the outer wall, the inner wall of the blood vessel is most strongly burned. Thrombus formation due to intimal injury is promoted. In addition, the internal elastic plate just outside the intima is also cauterized and destroyed, causing ulceration in the lumen and causing restenosis.

Therefore, according to the present invention, the inner membrane surface is not cauterized by radiating a laser beam, a high frequency current (voltage) or far infrared rays from the left side while operating the system for cooling the inside of the balloon, so that the inner membrane and the outer membrane are not cauterized. An object of the present invention is to provide a balloon catheter which is cauterized and expanded.

[0005]

The balloon catheter of the present invention is installed on the catheter shaft 1, a balloon 2 which can be inflated and deflated on the outer circumference of the catheter shaft 1, and a catheter shaft 1, as shown in FIG. In a balloon catheter having a high-frequency electrode 3 and a liquid delivery path 6 for supplying or absorbing the liquid 6a into the balloon 2, a plurality of catheters 1 in the balloon 2 are perfused with the cooling liquid 6a. A small hole 5 is provided.

[0006]

According to the present invention, the balloon 2 is inflated while the vascular stenosis is heated by the high-frequency energization method or the laser method, and at the same time, the intimal surface of the blood vessel which is in contact with the balloon 2 is protected from cauterization by the cooling system. .

[0007]

Embodiments of the balloon catheter of the present invention will be described below with reference to the accompanying drawings. FIG. 1 shows a balloon cooling system in the high-frequency electric heating method. 1A, B
In C and 1, 1 is, for example, a radiopaque catheter shaft made of Teflon.
A balloon 2 that can be inflated and deflated is formed at the tip of the balloon. Reference numeral 3 is a monopolar electrode for high-frequency electricity provided on the catheter shaft 1 of the balloon 2, and the monopolar electrode 3 has, for example, a conductor wire having a diameter of 0.1 mm wound around the catheter shaft 1 in a coil shape. . Further, a thermistor 4 is installed at the base of the catheter shaft 1 inside the balloon 2 so that the temperature inside the balloon 2 can be monitored by a temperature sensor 8. Further, a large number of small holes 5 are provided in the catheter shaft 1 of the balloon 2, and these small holes 5 are made to communicate with the inner cavity of the catheter shaft 1 of the balloon 2 and serve as an outlet for the liquid 6a in the balloon 2. A liquid delivery path 6 communicating with the inner lumen 2a of the balloon 2 is formed over the entire axial length of the catheter shaft 1.
A conducting wire 7a for energizing high frequency and a conducting wire 8a for the thermistor are contained in the inside. A liquid feed pump 9 is connected to the other end of the liquid feed path 6. By operating the liquid feeding pump 9 to feed the cooling liquid 6a to the balloon 2, the cooling liquid 6a can be inflated, and when the internal pressure of the balloon 2 rises above a certain level, from the small hole 5 formed in the catheter shaft 1 inside the balloon 2. The cooling liquid 6a is discharged, and the inside of the balloon 2 is cooled.

As shown in FIG. 2, while expanding the balloon 2, one end of the output terminal of the high frequency generator 7 having a frequency of 13.56 MHZ is connected to the electric wire 7a leading to the high frequency current supplying electrode 3 in the balloon 2, and the other end is connected to the back part. When connected to the installed counter electrode plate 10 (a metal disk having a diameter of about 10 cm) and energized with an output of 10 to 50 W, the tissue that comes into contact with the balloon 2 by the electromagnetic waves radially emitted from the balloon 2 according to the principle of dielectric heating = vessel stenosis The molecules and electrons of the part 11 are stirred and generate heat. At this time, the temperature inside the balloon is adjusted to the catheter shaft 1
It can be monitored by the thermistor 4 attached to the base of the.

When the liquid delivery pump 9 is continuously operated and the internal pressure of the balloon 2 is raised to a certain level or higher, the cooling liquid 6a is discharged from the balloon 2
Small hole 5 opened in the catheter shaft 1 after perfusion
Through the lumen of the catheter shaft 1 to the periphery of the blood vessel. At this time, the guide wire 12 can be pushed into the lumen of the catheter shaft 1. The internal pressure of the balloon 2 and the internal temperature of the balloon 2 can be freely controlled by adjusting the temperature and the injection speed of the cooling liquid 6a in the liquid feed pump 9.

As described above, while the balloon 2 is pressurized and perfused in the balloon 2 by the liquid delivery pump 9, electromagnetic waves are radiated by high-frequency current, so that the media and adventitia are mainly formed rather than the intima surface. It has become possible to expand the stenosis 11 more safely at a lower pressure while cauterizing.

FIG. 3 shows another embodiment of the present invention. In this example, a small hole 5a is provided in the joint portion 13 of the distal end of the balloon 2 with the catheter shaft 1, and the cooling liquid 6a perfused in the balloon 2 is discharged to the outside of the balloon 2 through this small hole 5a.

FIG. 4 shows another embodiment of the present invention. In this example, the balloon 2 has a large number of small holes 5b,
The cooling liquid 6a perfused in the balloon 2 is discharged to the outside of the balloon 2 through the small hole 5b of the balloon membrane. At this time, if various chemical substances such as a vascular smooth muscle growth inhibitor or an antithrombotic agent are dissolved in the cooling liquid 6a, it is possible to inject them directly into the blood vessel wall.

FIG. 5 shows another embodiment of the present invention. In this example, the cooling perfusion liquid 6a is fed from the lumen of the catheter shaft 1 into the balloon 2 by the liquid feeding pump 9 through the small hole 5 provided at the distal end portion of the catheter shaft, and then perfused in the balloon 2. The liquid is discharged to the outside from the liquid supply path 6 that leads from the catheter shaft 1 in the balloon 2 to the inner cavity 2a of the balloon 2 formed over the entire length of the catheter shaft 1. This cooling system is different from the former three. The circuit is closed, not open. In addition, the type of balloon catheter is On The Wire Tipe (a type in which a guide wire is fixed). It should be easily understood that the present invention can be applied to the case where the heat source is a laser beam or far infrared ray. The present invention is also applicable to strictures of the urethra, ureter, biliary tract and bronchi. Further, the present invention is not limited to the above-described embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0014]

The balloon catheter of the present invention is equipped with a heating and ablation system by high-frequency energization, a cooling system by perfusion in the balloon, and a temperature control system by the thermistor in the balloon. By applying pressure while heating the membrane, it is possible to provide a balloon catheter in which the occluded portion can be satisfactorily expanded without causing damage to the intimal membrane.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part showing an embodiment of a balloon catheter of the present invention.

FIG. 2 is a diagram for explaining FIG. 1;

FIG. 3 is a sectional view showing a main part of another embodiment of the present invention.

FIG. 4 is a cross-sectional view showing the main parts of another embodiment of the present invention.

FIG. 5 is a cross-sectional view showing the main parts of another embodiment of the present invention.

[Explanation of symbols]

 1 Catheter Shaft 2 Balloon 3 Monopolar Electrode 4 Thermistor 5 Small Hole 6 Liquid Delivery Pathway 9 Liquid Delivery Pump 11 Vascular Stenosis

Claims (4)

(57) [Claims] 1. A catheter shaft, an inflatable and deflatable balloon provided on the outer circumference of the catheter shaft, an electrode for high-frequency energization provided on the catheter shaft, and a delivery device for supplying or absorbing a liquid into the balloon. A balloon catheter provided with a liquid path, wherein a plurality of small holes for perfusing a cooling liquid are provided in the catheter shaft in the balloon. 2. A catheter shaft, an inflatable and deflatable balloon provided on the outer circumference of the catheter shaft, an electrode for high-frequency current supply provided on the catheter shaft, and a delivery device for supplying or absorbing a liquid into the balloon. A balloon catheter having a liquid passage, wherein a small hole for perfusion is provided between the balloon tip portion and the catheter shaft. 3. A catheter shaft, an expandable / contractible balloon provided on the outer periphery of the catheter shaft, an electrode for high-frequency current supply installed on the catheter shaft, and a delivery device for supplying or absorbing a liquid into the balloon. A balloon catheter having a liquid passage, wherein the balloon has a plurality of small holes. 4. The balloon catheter according to claim 1, wherein the distal end of the shaft is closed to form a closed perfusion system.