JP2005058506A - Ablation catheter with balloon - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce burdens on a patient due to catheter invasion. <P>SOLUTION: In an ablation catheter of this invention, a potential detection mechanism 16 composed of an electrode 17 for potential detection and a lead wire 18 for detected potential take-out and a potential detection mechanism 19 composed of an electrode 20 for potential detection and a lead wire 21 for detected potential take-out are attached, and after the thermocautery of a target lesion, a potential around a cauterized part is detected by the attached potential detection mechanisms 16 and 19 without pulling out the ablation catheter and the properness / improperness of thermocautery is discriminated. When a discriminated result is the improperness, a balloon 2 is immediately expanded again and a thermocautery process is repeatedly performed. Thus, the need of introducing a catheter for potential detection and introducing the ablation catheter again when the thermocautery is improper is eliminated and invasion burdens due to the introduction of the catheter for the potential detection and the re-introduction of the ablation catheter are completely eliminated. As a result, the burdens on the patient due to the catheter invasion are reduced. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an internal electrode for high-frequency energization in a balloon and a high-frequency energization arranged as a counter electrode on the patient body surface in a state in which the balloon disposed on the distal end side of the catheter is in close contact with a target lesion site in the patient. The present invention relates to an ablation catheter with a balloon that ablates a target lesion site by heating the target lesion site by performing high-frequency dielectric heating between the outer electrodes by high-frequency energization and Joule heating. The present invention relates to a technique for reducing a burden on a patient due to catheter invasion in ablation treatment for a site.

  An ablation catheter with a balloon for pulmonary vein electrical isolation described in JP-A-2002-78809 is an ablation catheter for performing cardiac arrhythmia treatment. When the pulmonary vein is electrically isolated using this ablation catheter with a balloon, as shown in FIG. 8, an inflatable / deflatable balloon 52 disposed on the distal end side of the catheter 51 is percutaneously cut into the inferior vena cava. The balloon 52 is introduced into the QA and pierced through the atrial septum Hw from the right atrium Ha of the heart HA while being pushed by the catheter 51 to reach the left atrium Hb. Then, after the balloon 52, which has been inflated firmly by supplying a liquid containing a contrast medium into the balloon, is brought into close contact with the pulmonary vein opening Qa, the coiled inner electrode 53 for high-frequency energization installed in the balloon 52 is used. The high frequency power is supplied from the high frequency power supply 55 to the planar high frequency energization outer electrode 54 set on the patient body surface as the counter electrode of the high frequency energization inner electrode 53.

  The annular peripheral edge portion of the pulmonary vein port Qa is entirely heated and cauterized by high-frequency dielectric heating and heating by Joule heat that occur in association with the high-frequency energization between the high-frequency energization inner electrode 53 and the high-frequency energization outer electrode 54. The Following cauterization of the pulmonary vein opening Qa, cauterization of the remaining three pulmonary vein openings Qb to Qd opened on the inner wall of the left atrium Hb is sequentially performed in the same manner. All the four pulmonary veins are electrically isolated by cauterizing the annular peripheral edge of each pulmonary vein opening Qa to Qd. When the annular peripheral edge of each pulmonary vein opening Qa to Qd is cauterized and each of the four pulmonary veins is in the form of electrical isolation, the electrical signal that causes arrhythmia is cut off and the cardiac arrhythmia is almost eliminated.

Thus, according to the ablation catheter with a balloon described in JP-A-2002-78809, the annular peripheral edge of each pulmonary vein opening Qa to Qd is cauterized as a whole, so that the cauterization is not repeated many times. At the same time, only the annular peripheral edge of each pulmonary vein opening Qa to Qd is cauterized, so that it is not necessary to cauterize an extra portion (for example, a healthy part).
Japanese Unexamined Patent Publication No. 2002-78809 (all pages of detailed description, FIGS. 1 to 6)

  However, in the case of ablation treatment for the target lesion site in the patient, there is a problem that the burden on the patient due to catheter invasion is not small and sometimes very large. After ablation with a balloon ablation catheter described in the above publication, after pulling out the ablation catheter with a balloon, another potential detection catheter (not shown) for detecting the potential around the ablation treatment site is introduced, This is because it is necessary to check whether or not cauterization has been properly performed, and a burden due to the invasion of the catheter for potential detection is added. If ablation is not done properly, the introduction of the ablation catheter with balloon and the catheter for potential detection will be repeated again, adding to the burden of catheter invasion of reintroducing the ablation catheter with balloon. Will become very large.

  The present invention has been made in view of such circumstances, and provides an ablation catheter with a balloon that can reduce a burden on a patient due to catheter invasion in ablation treatment for a target lesion site in a patient. With the goal.

  In order to achieve such an object, the present invention has the following configuration.

  That is, the ablation catheter with a balloon according to claim 1 is attached to the distal end side of the catheter and is inflatable and deflateable to be pressed against a target lesion site to be ablated, and is installed in the balloon. In an ablation catheter with a balloon provided with an internal electrode for high-frequency energization and a temperature sensor installed in the balloon, for detecting a potential around the ablation treatment site attached to the distal end surface of the catheter It is characterized by comprising a potential detection means comprising an electrode and a detection potential extraction lead wire that is passed through the catheter from the rear end side of the catheter and connected to the potential detection electrode. .

  (Operation / Effect) When the target lesion site in the patient body is cauterized using the ablation catheter with a balloon of the invention of claim 1 (hereinafter abbreviated as “ablation catheter” where appropriate), the inflation is arranged on the distal end side of the catheter.・ Introduce percutaneously into the patient's body in a deflated balloon and allow the balloon to reach the target lesion site while pushing it with the catheter, and introduce the liquid into the balloon via the catheter and inflate it firmly. . Subsequently, in a state where the inflated balloon is pressed against and closely adhered to the target lesion site to be ablated, high-frequency power is supplied, and the patient's body is used as a counter electrode for the high-frequency energization inner electrode (hereinafter abbreviated as “inner electrode” where appropriate). High frequency energization is performed between the outer electrode for planar high frequency energization separately set at an appropriate position in the table. While performing heating by high-frequency dielectric heating and Joule heating, the heating temperature is detected by the temperature sensor in the balloon, and high-frequency power is supplied in a supply amount corresponding to the temperature measurement result of the temperature sensor. The heating and Joule heating temperature is controlled. As this high-frequency dielectric heating by high-frequency energization and heating by Joule heat occur around the balloon, the balloon contact portion of the target lesion site is heated together with the balloon and locally cauterized.

  In the case of the ablation catheter according to the first aspect of the present invention, when the target lesion site is cauterized, the balloon is deflated as necessary without pulling out the ablation catheter, and potential detection for the potential detection means is performed. Whether the cauterization electrode is positioned in the vicinity of the ablation site or not is determined in accordance with the detection potential extracted by the detection potential extraction lead. If the determination is appropriate, pull out the ablation catheter. If the determination result is inappropriate, the balloon is inflated again and the cauterization process of the target lesion site is repeated.

  Thus, the ablation catheter according to the first aspect of the present invention is provided with the potential detecting means for detecting the potential around the ablation site, and when the target lesion site is cauterized, the ablation catheter is not pulled out and is attached. The detection means detects the potential around the ablation site to determine the appropriateness or inappropriateness of the ablation, and if the determination result is inappropriate, the balloon can be immediately inflated again to repeat the ablation process. If the catheter for introduction or cauterization is inappropriate, the reintroduction of the ablation catheter becomes unnecessary, and the burden of invasion due to the introduction of the potential detection catheter or the reintroduction of the ablation catheter is completely eliminated. Therefore, according to the ablation catheter with a balloon according to the first aspect of the invention, it is possible to reduce the burden on the patient due to the catheter invasion in the cauterization treatment for the target lesion site in the patient.

  Further, in ablation using a conventional ablation catheter (having an electrode of several mm at the tip and being cauterized several times in a dotted manner), the potential must be confirmed at a plurality of positions. Otherwise, it is not possible to identify the location where the shochu is defective, and it is not possible to identify the shochu point. Further, if it is attempted to confirm the potentials at many points at once, it is necessary to attach a large number of potential detection electrodes to the potential measurement catheter, which causes an increase in the cost and size of the catheter.

  On the other hand, since the ablation catheter with a balloon according to the first aspect of the present invention performs a wide range of cauterization along the entire circumference of the balloon with one cauterization, the location of the cauterization abnormality is specified as in the conventional example. There is no need to determine whether or not there is an abnormality (whether or not a potential is detected) in the cauterized area. If there is an abnormality, the area can be cauterized again. Therefore, unlike the conventional example, it is not necessary to provide a large number of potential detection electrodes on the catheter. In addition, since it is not necessary to identify an abnormal part, it is not necessary to apply (contact) the electrode to the specific part as in the conventional example, and it is only necessary to position the electrode in the vicinity of the ring-shaped cauterized region. . Therefore, according to the first aspect of the present invention, the number of expensive potential detection electrodes can be reduced, and the cost and size of the catheter can be reduced.

  According to a second aspect of the present invention, in the ablation catheter with a balloon according to the first aspect, the potential detection means is a potential detection electrode attached ahead of the front end of the balloon.

  (Operation / Effect) According to the invention of claim 2, since the potential detecting electrode is attached at a position ahead of the front end of the balloon, the potential at a location ahead of the front end of the balloon is also present around the ablation treatment site. It can be easily detected. For example, since the potential of the part can be detected without inserting a catheter deep into the pulmonary vein, damage to the deep part of the pulmonary vein can be avoided.

  According to a third aspect of the present invention, in the ablation catheter with a balloon according to the first aspect, the potential detection means is a potential detection electrode attached in front of the rear end of the balloon.

  (Function / Effect) According to the invention of claim 3, since the electrode for potential detection is attached at a position before the rear end of the balloon, the electrode in the place before the rear end of the balloon is also located around the ablation site. The potential can be easily detected.

  According to a fourth aspect of the present invention, in the ablation catheter with a balloon according to the first aspect, the electric potential detecting means is attached to the electric potential detecting electrode attached before the front end of the balloon and before the rear end of the balloon. And a potential detection electrode.

  (Operation / Effect) According to the invention of claim 4, since the potential detection electrode is attached to both the position ahead of the front end of the balloon and the position before the rear end of the balloon, Any potential at a location ahead of the front end of the balloon and a location before the rear end of the balloon can be easily detected.

  The invention of claim 5 is the ablation catheter with balloon according to any one of claims 1 to 4, wherein the catheter is concentrically threaded so that the outer tube shaft and the inner tube shaft are movable in the axial direction. The front end of the balloon is fixed to the front end of the inner cylindrical shaft, the rear end of the balloon is fixed to the front end of the outer cylindrical shaft, and high frequency energization The internal electrode is shaped like a coil and is concentrically inserted on the inner cylinder shaft.

  According to the invention of claim 5, the shape of the balloon can be changed in various ways by moving the outer cylinder shaft or the inner cylinder shaft in the axial direction. Since the inner electrode for high frequency energization is substantially integrated with the inner cylinder shaft by concentrically extrapolating to the inner cylinder shaft, the introduction of the balloon becomes smoother.

  Further, the invention of claim 6 is the ablation catheter with a balloon according to claim 5, wherein the lead wire for taking out the detection potential is covered with an electrically insulating protective coating, and is formed between the outer tube shaft and the inner tube shaft. It is derived through the gap.

  (Operation / Effect) According to the invention of claim 6, since the catheter is also used as a pipe for derivation of the lead for extracting the detection potential, the lead does not interfere with the cauterization process.

  The invention of claim 7 is the ablation catheter with a balloon according to claim 6, wherein the electrically insulating protective coating of the lead wire for detecting the detection potential is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride. .

  (Effect / Effect) According to the invention of claim 7, the electrical insulating protective coating of the lead for detecting the detection potential is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride, and the electrical insulating protective coating has an electrical insulating property. As a result, leakage / intrusion of high-frequency power is further suppressed, and heat generation of the catheter due to leakage / intrusion of high-frequency power is sufficiently suppressed.

  The invention according to claim 8 is the ablation catheter with balloon according to claim 5, wherein the lead wire for taking out the detected potential is led out through a thick part of at least one of the outer cylindrical shaft and the inner cylindrical shaft. It is what is done.

  (Operation / Effect) According to the invention of claim 8, the lead wire for taking out the detected potential is led out through the thick portion of at least one of the outer cylinder shaft and the inner cylinder shaft. It can be easily electrically insulated.

  The invention according to claim 9 is the ablation catheter with balloon according to claim 5, wherein the detection potential extracting lead wire connected to the potential detection electrode attached ahead of the front end of the balloon is an inner cylinder. The lead wire for extracting the detection potential, which is led out through the thick part of the shaft and connected to the potential detection electrode attached in front of the rear end of the balloon, is led out through the thick part of the outer tube shaft. It is what is done.

  (Operation / Effect) According to the invention of claim 9, since two lead wires for taking out the detection potential are individually led out through the thick portions of the inner and outer cylindrical shafts, the electrical insulation of each lead wire is achieved. It can be made more reliable.

  The invention according to claim 10 is the balloon ablation catheter according to any one of claims 5 to 9, wherein the high-frequency energizing inner electrode is extrapolated to the inner cylinder shaft without restricting the inner cylinder shaft. In addition to being fixed to the outer cylinder shaft side, the temperature sensor is fixed to the inner electrode for high-frequency energization.

  (Operation / Effect) According to the invention of claim 10, the inner cylindrical shaft can move smoothly without being restrained by the high frequency energizing inner electrode. Furthermore, since the inner electrode for high-frequency energization is fixed to the outer tube shaft to which the rear end of the balloon is fixed, and the temperature sensor is fixed to the inner electrode for high-frequency energization, The installation position of the inner electrode and the temperature sensor is stabilized.

  The invention according to claim 11 is the ablation catheter with balloon according to any one of claims 1 to 10, wherein the temperature is measured from a power supply lead wire for supplying high-frequency power to the inner electrode for high-frequency energization and a temperature sensor. Each of the sensor lead wires for taking out signals is passed through the catheter with an electrically insulating protective coating.

  (Operation / Effect) According to the invention of claim 11, the sensor lead wire for taking out the temperature measurement signal from the temperature sensor and the power feeding lead wire for feeding the high frequency power to the high frequency energizing inner electrode are drawn to the catheter. Since it is passed, the catheter can also serve as a lead wire pipe. In addition, since both the sensor lead wire and the power supply lead wire have an electrically insulating protective coating, there is no risk of short-circuit between the lead wires, and at the same time, leakage and intrusion of high-frequency power can be suppressed. As a result, the heat generation of the catheter due to leakage and intrusion of high-frequency power is suppressed, and the forced cooling mechanism of the catheter can be omitted.

  According to a twelfth aspect of the present invention, in the ablation catheter with a balloon according to the eleventh aspect, the electrically insulating protective coating of the lead wire for power supply is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride.

  (Effect / effect) According to the invention of claim 12, the electrical insulating protective coating of the power supply lead wire is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride, and the electrical insulating protective coating has an electrical insulating property. As a result, leakage / intrusion of high-frequency power is further suppressed, and heat generation of the catheter due to leakage / intrusion of high-frequency power is sufficiently suppressed.

  The invention of claim 13 is the ablation catheter with balloon according to claim 11, wherein the electrically insulating protective coating of the sensor lead wire is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride.

  According to the invention of claim 13, the electrical insulation protective coating of the sensor lead wire is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride, and the electrical insulation of the electrical insulation protective coating is increased. In addition, heat generation of the catheter due to leakage and intrusion of high-frequency power can be sufficiently suppressed.

  The invention of claim 14 is the ablation catheter with balloon according to any one of claims 1 to 13, wherein a forced cooling mechanism for the catheter is not provided.

  (Operation / Effect) According to the invention of claim 14, since the forced cooling mechanism of the catheter is omitted, it is possible to make the catheter thinner so that the catheter can be easily inserted into the patient.

  Further, the invention of claim 15 is the ablation catheter with balloon according to any one of claims 1 to 14, wherein the liquid feeding means for feeding the liquid into the balloon via the catheter and the temperature measurement result of the temperature sensor. Power supply means for supplying high-frequency power with a supply amount according to the above.

  According to the invention of claim 15, the balloon can be inflated firmly by feeding the liquid into the balloon through the catheter by the liquid feeding means. In addition, the heating temperature of the high-frequency dielectric heating and Joule heat can be accurately controlled by supplying high-frequency power with a supply amount corresponding to the temperature measurement result of the temperature sensor by the power supply means.

  The invention of claim 16 is the ablation catheter with balloon of claim 15, wherein the liquid fed by the liquid feeding means passes through the clearance between the outer cylinder shaft and the inner cylinder shaft.

  (Operation / Effect) According to the invention of claim 16, the clearance between the outer cylinder shaft and the inner cylinder shaft can be used as a flow path for liquid feeding by the liquid feeding means.

  The invention according to claim 17 is the ablation catheter with balloon according to claim 15 or 16, wherein the liquid in the balloon inflated by the liquid fed by the liquid feeding means enters and exits between the catheter and the balloon. And a liquid agitating means for agitating the liquid in the balloon.

  (Operation / Effect) According to the invention of claim 17, during the heating by high frequency dielectric heating and Joule heating, the liquid in the balloon in an expanded state is introduced between the catheter and the balloon by the liquid stirring means. When the liquid inside the balloon is moved in and out and the liquid inside the balloon is agitated, liquids with different temperatures are mixed together to make the liquid temperature inside the balloon uniform, and heating unevenness due to high frequency dielectric heating and Joule heat can be suppressed.

  As described above, in the case of the ablation catheter with a balloon according to the present invention, the potential detection means for detecting the potential around the ablation treatment site attached to the distal end surface of the catheter is attached, and the ablation of the target lesion site is performed. Once the ablation catheter is not pulled out, the attached potential detection means is used to detect the potential around the ablation site to determine the appropriateness / inappropriateness of the ablation, and immediately if the determination result is appropriate Since the balloon can be inflated again and the cauterization process can be repeated, there is no need to introduce an electric potential detection catheter or an ablation catheter when cauterization is inappropriate, and an electric potential detection catheter or an ablation catheter is reintroduced. The burden of invasiveness due to is eliminated. Therefore, according to the ablation catheter with a balloon of the present invention, it is possible to reduce the burden on the patient due to the catheter invasion in the cauterization treatment for the target lesion site in the patient.

  Hereinafter, embodiments of the ablation catheter with a balloon of the present invention will be described. FIG. 1 is a plan view showing the overall configuration of the ablation catheter according to the embodiment, FIG. 2 is a cross-sectional view showing the inside of the balloon of the ablation catheter of the embodiment, and FIG. FIG. The ablation catheter of this embodiment is suitable for pulmonary vein electrical isolation.

  In the ablation catheter of the embodiment, a balloon 2 that can be inflated and deflated is disposed on the distal end side of the catheter 1. The catheter 1 is a double tube type catheter in which an outer tube shaft 3 and an inner tube shaft 4 are concentrically connected to each other so as to be movable in the axial direction, and the front end portion of the balloon 2 is connected to the distal end portion of the inner tube shaft 4. It is fixed, the rear end of the balloon 2 is fixed to the front end of the outer cylinder shaft 3, and a liquid inlet 2A is provided at the rear end of the balloon. In the case of the double tube type catheter 1, the shape of the balloon 2 can be variously changed by moving the outer tube shaft 3 or the inner tube shaft 4 in the axial direction. Therefore, in the present invention, the catheter 1 is preferably a double tube catheter, but the catheter 1 is not necessarily limited to a double tube catheter, and a single tube catheter is preferable depending on the type of treatment. There is also.

  The length of the outer cylinder shaft 3 and the inner cylinder shaft 4 is about 1 m to about 1 m and several tens of centimeters. The outer diameter of the outer cylinder shaft 3 is about 3 mm to 5 mm, and the inner diameter is about 2 mm to 4 mm. The outer diameter of the inner cylinder shaft 4 is about 1 mm to 3 mm, and the inner diameter is about 0.5 mm to 2 mm. As the material of the outer cylinder shaft 3 and the inner cylinder shaft 4, a flexible material having excellent antithrombogenicity is used. Specifically, a fluororesin, a polyamide resin, a polyimide resin, etc. are mentioned, for example.

  As shown in FIG. 3, the balloon 2 has a conical shape (conical tip conical shape) whose diameter is reduced on the distal end side in the inflated state. The balloon 2 has a length (length d along the balloon center axis 2a that virtually connects the balloon front end and the balloon rear end) of about 20 mm to 40 mm, and the maximum outer diameter on the rear end side is about 10 mm to 40 mm. The film thickness is 100 μm to 300 μm. When the outer diameter of the balloon 2 has a conical shape with a tapered shape, the balloon can be prevented from entering the pulmonary vein, and the balloon 2 can be inserted into the pulmonary vein mouth by slightly inserting the tip of the balloon 2 into the pulmonary vein mouth. Since it is closely attached, the entire annular peripheral edge of the pulmonary vein opening can be reliably cauterized. The shape of the balloon 2 when it is inflated is not limited to a conical shape, and may be another shape such as a barrel-like shape. As the material of the balloon 2, a stretchable material excellent in antithrombogenicity is used. In particular, polyurethane-based polymer materials are preferable, and specific examples include thermoplastic polyether urethane, polyether polyurethane urea, fluorine polyether urethane urea, polyether polyurethane urea resin, and polyether polyurethane urea amide.

  Furthermore, in the case of the ablation catheter of the embodiment, an inner electrode for high-frequency energization (hereinafter abbreviated as “inner electrode” as appropriate) 5 formed by winding an electric wire around the balloon 2 and forming it in a coil shape is installed. 2, a liquid feeding device (liquid feeding means) 6 for feeding liquid from the liquid inlet 2A via the catheter 1 is connected to the distal end side of the catheter 1 via a four-way connector CN. As the electric wire of the inner electrode 5, a high conductivity metal wire such as a silver wire, a gold wire, a platinum wire, or a copper wire is used.

  The inner electrode 5 is concentrically inserted on the inner cylinder shaft 4 without restricting the inner cylinder shaft 4. The inner diameter of the inner electrode 5 is slightly larger than the outer diameter of the inner cylindrical shaft 4, and a slight gap is formed between the inner surface of the inner electrode 5 and the outer surface of the inner cylindrical shaft 4. Thus, when the inner electrode 5 is concentrically inserted into the inner cylinder shaft without restraining the inner cylinder shaft 4, the inner electrode 5 is substantially integrated with the inner cylinder shaft 4 and obstructs it. The inner cylinder shaft 4 can be moved very smoothly.

  The ablation catheter of the embodiment includes a planar high-frequency energizing outer electrode 7 as a counter electrode of the inner electrode 5, and the outer electrode 7 is placed at an appropriate position on the patient body surface, for example, a double-sided tape (not shown). ) Is pasted and set. During heating by high-frequency dielectric heating and Joule heating, high-frequency energization is performed between the inner electrode 5 and the outer electrode 7 to cause heating. The appropriate temperature for tissue cauterization during high frequency dielectric heating and Joule heating is usually in the range of 50 ° C to 70 ° C. As the material of the outer electrode 7, for example, a thin plate or sheet made of a highly electrically conductive metal such as copper or aluminum is used.

  On the other hand, the liquid feeding device 6 is provided with a liquid feeding roller pump (not shown), and the liquid fed by the liquid feeding roller pump passes through the clearance between the outer cylinder shaft 3 and the inner cylinder shaft 4. Then, it is fed into the balloon 2 from the liquid inlet 2A. As the liquid from the liquid feeding device 6 is fed into the balloon 2, the balloon 2 is firmly inflated. That is, the clearance between the outer cylinder shaft 3 and the inner cylinder shaft 4 is used as a flow path for liquid feeding by the liquid feeding device 6.

  Further, in the case of the ablation catheter of the embodiment, a diaphragm type stirring mechanism (liquid) that stirs the liquid in the balloon 2 by moving the balloon 2 in and out of the balloon 2 through the catheter 1 by injecting the liquid. (Stirring means) 8 is provided. By the stirring by the stirring mechanism 8, liquids having different temperatures are mixed to make the liquid temperature in the balloon uniform, and heating unevenness due to high frequency dielectric heating and Joule heat can be suppressed.

  Furthermore, in the ablation catheter of the embodiment, a high-frequency power source (high-frequency power supply for supplying high-frequency power from the temperature sensor 9 installed in the balloon 2 and the supply electrode according to the temperature measurement result of the temperature sensor 9 from the high-frequency energization inner electrode) Power supply means) 10. The frequency of the high-frequency power ranges from several MHz to several hundred MHz, and is usually around 10 MHz. During execution of heating by high-frequency dielectric heating and Joule heat, the heating temperature is detected by the temperature sensor 9 in the balloon 2 and fed back to the high-frequency power source 10, and the high-frequency power source 10 responds to the temperature measurement result of the temperature sensor 9. By supplying high-frequency power with the supply amount, the heating temperature by high-frequency dielectric heating and Joule heat is controlled. In addition, the inner electrode 5 is fixed to the outer cylinder shaft 3 to which the rear end portion of the balloon 2 is attached, and the temperature sensor 9 is fixed to the inner electrode 5. As a result, the installation positions of the inner electrode 5 and the temperature sensor 9 in the balloon 2 are stabilized. The temperature sensor 9 is exemplified by a thermocouple, but is not limited to a thermocouple, and for example, a semiconductor type temperature measuring element or the like can be used.

  Further, as shown in FIG. 4, both the sensor lead wire 11 for extracting a temperature measurement signal from the temperature sensor 9 and the power feeding lead wire 12 for feeding high frequency power to the high frequency energizing inner electrode are electrically insulated. With the coverings 13 and 14, the clearance between the outer cylinder shaft 3 and the inner cylinder shaft 4 of the catheter 1 is drawn through. That is, the clearance between the outer cylinder shaft 3 and the inner cylinder shaft 4 is used as piping for the sensor lead wire 11 and the power supply lead wire 12. In addition, since the sensor lead wire 11 and the power supply lead wire 12 are both provided with an electrically insulating protective coating 13, 14, there is no risk of short-circuiting between the lead wires, and at the same time, leakage of high-frequency power Intrusion is suppressed, and heat generation of the outer cylinder shaft 3 and the inner cylinder shaft 4 due to leakage and intrusion of high-frequency power is suppressed. As a result, in the case of the ablation catheter of the embodiment, the forced cooling mechanism of the catheter 1 is omitted. However, a forced cooling mechanism for the catheter 1 may be provided in the catheter 1 as necessary.

  Examples of the material for the sensor lead wire 11 and the power supply lead wire 12 include copper, silver, platinum, tungsten, and alloy wires. Further, when the electrical insulating protective coatings 13 and 14 are made of a material having a relative dielectric constant smaller than that of polyvinyl chloride, the electrical insulating properties of the electrical insulating protective coatings 13 and 14 are improved. The heat generation of the outer cylinder shaft 3 and the inner cylinder shaft 4 due to leakage and intrusion of high-frequency power is further suppressed. Further, the fact that the outer cylinder shaft 3 and the inner cylinder shaft 4 are made of a material having a relative dielectric constant smaller than that of polyvinyl chloride also prevents heat generation of the outer cylinder shaft 3 and the inner cylinder shaft 4 due to leakage and intrusion of high-frequency power. It is valid. In the case of the embodiment, the power supply lead wire 12 is also formed using the same copper wire as the inner electrode 5. However, the power supply lead wire 12 manufactured separately is connected to the inner electrode 5. It may be.

  As a material having a relative dielectric constant smaller than that of polyvinyl chloride, a material having a relative dielectric constant of 10 MHz at 3 or less, more preferably 10 MHz at a relative dielectric constant of 1 or less can be mentioned. This relative dielectric constant ε can be measured as follows.

ε = Cx / Co
However, Cx is the capacitance of the measuring capacitor Cs when the bridge is balanced Co is the capacitance of ε = 1 calculated from the area of the main electrode and the thickness of the test piece, and is calculated by the following equation.

Co = r ² /3.6t
r: radius of main electrode (cm), t: thickness of test piece (cm)
Specific examples of materials having a lower relative dielectric constant than polyvinyl chloride include fluorine polymer compounds such as polytetrafluoroethylene (PTFE) and tetrafluoroethylene-6-fluoropropylene copolymer (FEP). Other examples include polyethylene, polypropylene, polyimide resin, polyamide resin, and the like. In addition, as an apparatus used for the measurement of the dielectric constant ε, for example, an RF impedance / material analyzer (HP4291A) manufactured by Hewlett-Packard Company may be used.

  Further, radiation shielding metal pipes 3A and 4A are attached to the tips of the outer cylinder shaft 3 and the inner cylinder shaft 4, and the front end portion and the rear end portion of the balloon 2 are attached to the metal pipes 3A and 4A, respectively. The outer cylinder shaft 3 and the inner cylinder shaft 4 are fixed. By providing the radiation shielding metal pipes 3A and 4A, when X-ray fluoroscopy is performed, the radiation shielding metal pipes 3A and 4A appear on the X-ray fluoroscopic image, so that the position of the balloon 2 in the patient body can be accurately determined. It becomes possible to grasp. Examples of the material of the radiation shielding metal pipes 3A and 4A include gold, platinum, and stainless steel.

  The ablation catheter according to the embodiment has a potential detection electrode 17 for detecting a potential around the ablation treatment site attached to the front end surface of the inner cylindrical shaft 4 and the inside of the catheter 1 from the rear end side of the catheter 1. The potential detection mechanism 16 including the detection potential take-out lead wire 18 that is passed through and connected to the potential detection electrode 17 and the potential around the ablation treatment site attached to the front end surface of the outer cylinder shaft 3 A potential detecting mechanism 19 including a potential detecting electrode 20 to be detected and a detection potential extracting lead wire 21 that is passed through the catheter 1 from the rear end side of the catheter 1 and connected to the potential detecting electrode 20; It has.

  The potential detection electrode 17 is shaped into a short cylinder having a height (length) of about 3 mm, and a synthetic resin pipe 22 is added to the tip of the inner cylindrical shaft 4 before the radiation shielding metal pipe 4A. In addition, the potential detection electrode 17 is fitted to the outer periphery of the synthetic resin pipe 22. The potential detection electrode 20 is also shaped into a short cylinder having a height (length) of about 3 mm, and is directly fitted to the outer periphery of the outer cylinder shaft 3. As a material for the potential detection electrodes 17 and 20, platinum, silver, copper with silver plating, or the like is used.

  As shown in FIG. 4, the lead wires 18 and 21 for taking out the electric potential are also passed through the clearance between the outer cylindrical shaft 3 and the inner cylindrical shaft 4 with the electrically insulating protective coatings 18A and 21A, and are electrically insulating. The protective coatings 18A and 21A are preferably made of a material having a relative dielectric constant smaller than that of polyvinyl chloride. In this case, since the electrical insulation of the electrical insulation protective coating is sufficient, the intrusion of high-frequency power can be sufficiently suppressed. The lead wire 18 may be led out through an elongated hole formed in the thick part of the inner cylinder shaft 4, and similarly, the lead wire 21 is led out through an elongated hole formed in the thick part of the outer cylinder shaft 3. Also good. In this case, if the lead wires 18 and 21 are electrically insulated by the thick portions of the shafts 4 and 3, it is not always necessary to cover the lead wires 18 and 21 with the electrically insulating protective coatings 18A and 21A.

  Note that the potential detected by the potential detection electrodes 17 and 20 is checked by connecting the detection potential extraction leads 18 and 21 to a normal electrocardiograph 23 as shown in FIG. (Or display monitor) and check.

  The usage of the ablation catheter of the embodiment having the above-described configuration will be described by taking as an example the case where the peripheral edge of the pulmonary vein opening of the heart is cauterized. As shown in FIG. 5, the balloon 2 in a contracted state is pushed forward by the catheter 1 along the guide wire GW introduced percutaneously into the patient's body, and is allowed to reach the right atrium Ha of the heart HA from the inferior vena cava QA. Thereafter, the balloon 2 is applied to the peripheral edge of the pulmonary vein opening Qa so as to be in close contact therewith. On the other hand, a planar outer electrode 7 is affixed to the patient's body surface with a double-sided adhesive tape (not shown) or the like, and the outer electrode 7 and the high-frequency power source 10 are connected by a power supply lead wire 15. Then, high-frequency energization is performed between the inner electrode 5 and the outer electrode 7 to heat and cauterize the peripheral edge of the pulmonary vein opening Qa. The remaining three pulmonary vein openings are cauterized in the same manner.

  When cauterization of the peripheral edge of the pulmonary vein is completed, the appropriateness / inappropriateness of the cauterization is determined using the potential detection mechanism 16 and the potential detection mechanism 19. When the potential detection mechanism 16 is used, as shown in FIG. 6, the ablation catheter is not pulled out (the balloon 2 is deflated if necessary), and the potential detection electrode 17 is placed around the ablation treatment site (for example, lungs). At the same time as being positioned in the vicinity of the inner surface of the vein, it is taken out by the detection potential take-out lead 18 and displayed on the chart of the electrocardiograph 23. Appropriate / unsuitable cauterization is determined from the detection results displayed on the chart. When the determination result is inappropriate, the balloon 2 is immediately inflated again and the cauterization process is repeated.

  Also in the case where the potential detection mechanism 19 is used, as shown in FIG. 7, the ablation catheter is not pulled out (the balloon 2 is contracted as necessary), and the potential detection electrode 20 is moved around the ablation treatment site (for example, the atrium). At the same time as the detection electric potential extracting lead 21 and displaying it on the chart of the electrocardiograph 23. Appropriate / inappropriate cauterization is determined from the detection results displayed on the chart. If the determination result is inappropriate, the balloon 2 is immediately inflated again and the cauterization process is repeated. Depending on the part for detecting the potential, the potential detection mechanism 16 and the potential detection mechanism 19 can be operated simultaneously to detect and check the potentials of the two parts at the same time. When all of the cautery is determined to be appropriate, the ablation catheter is withdrawn and treatment is completed.

  As described above, when the ablation catheter of the embodiment is ablated, the potential around the ablation treatment site is detected by the potential detection mechanism 16 and the potential detection electrode 20 attached to the catheter 1 without pulling out the ablation catheter. In addition to determining whether the cauterization is appropriate or inappropriate, if the determination result is inappropriate, the balloon 2 can be immediately inflated again and the cauterization process can be repeated, so introduction of the potential detection catheter or cauterization is inappropriate. In this case, reintroduction of the ablation catheter becomes unnecessary, and the burden of invasion due to the introduction of the potential detection catheter and the reintroduction of the ablation catheter is completely eliminated. As a result, the burden on the patient due to catheter invasion can be reduced.

  Next, specific examples of the ablation catheter of the present invention will be described.

  [Example] First, a balloon 2 having a conical shape with a conical tip having a length of 30 mm at the front end of the balloon and a rear end of the balloon, a maximum outer diameter of 30 mm at the rear end, and a membrane thickness of 160 μm was prepared as follows. . That is, a glass balloon mold having a mold surface corresponding to a desired balloon shape is immersed in a 13% concentration polyurethane solution, and the solvent is evaporated by applying heat to form a urethane polymer film on the mold surface. Balloon 2 was produced by the method.

  On the other hand, a polyamide resin tube having an outer diameter of 3.8 mm, an inner diameter of 2.7 mm, and an overall length of 80 cm is used as the outer cylindrical shaft 3 of the catheter 1, and a stainless steel pipe having a diameter of 3.1 mm and a length of 7 mm and a sandblasted outer surface is used. After the metal pipe 3A is inserted into the tip of the tube, it is tied and fixed with a 0.1 mm nylon thread, and a potential detection electrode 20 having an outer diameter of 4.0 mm, an inner diameter of 3.8 mm, and a height of 3 mm is attached to the tip. After the lead wire 21 for detecting potential detection with an electrical insulation protective coating is passed through from the inside of the outer cylindrical shaft 3 covered with the potential detection electrode 20 and connected with an adhesive. After the four-way connector CN was inserted and fitted to the rear end, it was tied and fixed with a 0.1 mm nylon thread.

  On the other hand, a polyamide resin tube having an outer diameter of 1.5 mm, an inner diameter of 1.1 mm, and an overall length of 90 cm is used as the inner cylindrical shaft 4, and a stainless steel pipe having a diameter of 1.2 mm and a length of 6 mm and a sandblasted outer surface is used as the metal pipe 4A. After being inserted into the tip of the tube, it was tied and fixed with a 0.1 mm nylon thread. Further, after a synthetic resin pipe 22 having an outer diameter of 2.0 mm, an inner diameter of 1.1 mm, and a length of about 10 mm is extrapolated and joined to the metal pipe 4A, the inner diameter is 2.0 mm, the outer diameter is 2.5 mm, and the height is increased. A 3 mm potential detection electrode 17 was extrapolated to the tip of the synthetic resin pipe 22 and fixed with an adhesive, and a detection potential extraction lead wire 18 with an electrical insulation protective coating was connected. Then, while the lead wires 18 and 21 for extracting the detection potential are pulled out to the rear end side of the catheter 1, the inner cylinder shaft 4 is inserted through the four-way connector CN, and then the cap of the four-way connector CN is tightened to double the cylinder. A catheter 1 of the type was prepared.

  Further, the tip portion of an electric annealed copper wire having a diameter of 0.5 mm subjected to silver plating of 0.1 μm is spirally wound over a length of 10 mm to be shaped into a coil to be an inner electrode 5 and ethylene tetrafluoride- An electrically insulating protective coating 14 was applied to other portions using a hexafluoropropylene copolymer (FEP) to obtain a power supply lead wire 12. Furthermore, as the temperature sensor 9, an ultrafine thermocouple double (copper-constantan) wire with poly (tetrafluoroethylene) and an electrically insulating protective coating 13 was prepared with a sensor lead wire 11.

  After the temperature sensor 9 is fixed to the inner electrode 5, the inner electrode 5 is inserted into the tip of the inner cylinder shaft 4, and then the sensor lead wire 11 and the power supply lead wire 12 are connected to the outer cylinder shaft 3 and the inner cylinder shaft. 4, the rear ends of the sensor lead wire 11 and the power supply lead wire 12 are pulled out from the four-way connector CN, and the sensor lead wire 11 and the tip of the power supply lead wire 12 are pulled out. This was fixed to the metal pipe 3A with an aramid fiber fixture. Finally, the front end of the balloon 2 is tied and fixed to the metal pipe 4A with 0.1 mm nylon thread, and the rear end of the balloon 2 is tied and fixed to the metal pipe 3A with 0.1 mm nylon thread. An ablation catheter was completed.

  [Potential detection test] Subsequently, a potential detection test for checking the potential detection function of the potential detection mechanism 16 and the potential detection mechanism 19 was performed on the ablation catheter of the example. One test subject (human) to be detected for potential was prepared in advance, and lead wires 18 and 21 for taking out detected potential were connected to the electrocardiograph 23.

  First, the potential detection electrode 17 of the potential detection mechanism 16 was applied to the body surface near the heart of the person under test, and the detected potential was recorded on the chart by the electrocardiograph 23. Next, the potential detection electrode 20 of the potential detection mechanism 19 was applied to the body surface near the heart of the person under test, and the detected potential was recorded on the chart by the electrocardiograph 23.

  The recorded results on the chart were all normal. This potential detection test is designed to detect the potential of the body surface of the subject, but if the potential of the body surface of the subject can be detected normally, the potential in the body of the subject can also be detected normally. It was confirmed that both the potential detection mechanism 16 and the potential detection mechanism 19 can detect the potential in the patient body appropriately.

  The present invention is not limited to the above-described embodiments, and can be modified as follows.

  (1) The ablation catheter of the embodiment has a configuration including all of the liquid feeding device 6, the high-frequency power source 10, or the outer electrode 7, but the liquid feeding device 6, the high-frequency power source 10 or the outer electrode 7 is actually used. Therefore, the ablation catheter of the present invention may be the catheter 1 that does not include the liquid feeding device 6, the high-frequency power source 10, or the outer electrode 7.

  (2) In the embodiment, the potential detection mechanism 16 in which the potential detection electrode 17 is attached ahead of the front end of the balloon 2 and the potential detection electrode 20 are in front of the rear end of the balloon 2. The ablation catheter having the same configuration as that of the embodiment except that only one of the potential detection mechanism 16 and the potential detection mechanism 19 is provided. It is mentioned as a deformation | transformation aspect.

  In the embodiment, only one potential detection mechanism 16 and one potential detection mechanism 19 are provided. However, the potential detection mechanism 16 and the potential detection mechanism 19 are not limited to one, and a plurality of potential detection mechanisms 16 and 19 are provided. They may be deployed.

It is a top view which shows the whole structure of the ablation catheter of embodiment. It is sectional drawing which shows the inside of the balloon which concerns on embodiment. It is a front view which shows the external shape at the time of expansion | swelling of the balloon which concerns on embodiment. It is a transverse cross section of the catheter concerning an embodiment. It is a mimetic diagram showing the situation at the time of cauterization of the pulmonary vein mouth by the ablation catheter of an embodiment. It is a schematic diagram which shows the condition at the time of the electric potential detection by the electric potential detection mechanism attached to the ablation catheter of embodiment. It is a schematic diagram which shows the condition at the time of the electric potential detection by the other electric potential detection mechanism attached to the ablation catheter of embodiment. It is a schematic diagram which shows the cauterization situation of the pulmonary vein opening by the ablation catheter with a balloon.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Catheter 2 ... Balloon 3 ... Outer cylinder shaft 4 ... Inner cylinder shaft 5 ... Inner electrode for high frequency electricity supply 6 ... Liquid delivery apparatus (liquid delivery means)
7 ... outer electrode for high frequency energization 8 ... Diaphragm type stirring mechanism (liquid stirring means)
9 ... Temperature sensor 10 ... High frequency power supply (power supply means)
DESCRIPTION OF SYMBOLS 11 ... Lead wire for sensors 12 ... Lead wire for electric power supply 13, 14 ... Electrical insulation protective coating 15 ... Lead wire for electric power supply 16, 19 ... Electric potential detection mechanism (electric potential detection means)
17, 20... Potential detection electrode 18, 21... Detection potential extraction lead 18A, 21A.

Claims (17)

  An inflatable / deflated balloon that is attached to the distal end side of the catheter and pressed against a target lesion site to be ablated, an inner electrode for high-frequency energization installed in the balloon, and a temperature sensor installed in the balloon An ablation catheter with a balloon comprising: a potential detection electrode for detecting a potential around an ablation site attached to the distal end surface of the catheter; and a catheter from the rear end side of the catheter. An ablation catheter with a balloon comprising a potential detection means comprising a detection potential extraction lead connected to the potential detection electrode.   The ablation catheter with a balloon according to claim 1, wherein the potential detection means is a potential detection electrode attached ahead of the front end of the balloon.   The ablation catheter with a balloon according to claim 1, wherein the potential detection means is a potential detection electrode attached in front of the rear end of the balloon.   The ablation catheter with a balloon according to claim 1, wherein the potential detection means includes a potential detection electrode attached before the front end of the balloon and a potential detection electrode attached before the rear end of the balloon. An ablation catheter with a balloon.   The ablation catheter with a balloon according to any one of claims 1 to 4, wherein the catheter is a double tube catheter in which an outer tube shaft and an inner tube shaft are concentrically connected to each other so as to be movable in an axial direction. The front end of the balloon is fixed to the front end of the inner cylinder shaft, the rear end of the balloon is fixed to the front end of the outer cylinder shaft, and the inner electrode for high-frequency energization is shaped into a coil. And an ablation catheter with a balloon that is concentrically extrapolated to the inner shaft.   6. The ablation catheter with a balloon according to claim 5, wherein the lead for detecting the detection potential is attached with a balloon led out through a gap between the outer cylinder shaft and the inner cylinder shaft in a state covered with an electrically insulating protective coating. Ablation catheter.       The ablation catheter with a balloon according to claim 6, wherein the electrically insulating protective coating of the detection potential extracting lead wire is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride.   6. The ablation catheter with a balloon according to claim 5, wherein the lead wire for taking out the detection potential is led out through a thick part of at least one of the outer cylinder shaft and the inner cylinder shaft.   6. The ablation catheter with a balloon according to claim 5, wherein the detection potential extraction lead wire connected to the potential detection electrode attached ahead of the front end of the balloon is led out through the thick portion of the inner cylindrical shaft. An ablation catheter with a balloon in which a lead for detecting a detection potential connected to a potential detection electrode attached in front of the rear end of the balloon is led out through a thick portion of the outer cylinder shaft.   The ablation catheter with a balloon according to any one of claims 5 to 9, wherein the high-frequency energizing inner electrode is externally inserted into the inner cylindrical shaft and fixed to the outer cylindrical shaft side without restraining the inner cylindrical shaft. In addition, an ablation catheter with a balloon in which a temperature sensor is fixed to an inner electrode for high-frequency energization.   The ablation catheter with a balloon according to any one of claims 1 to 10, wherein a power supply lead wire for supplying high-frequency power to the high-frequency energization inner electrode and a sensor lead wire for extracting a temperature measurement signal from the temperature sensor are provided. Both are ablation catheters with balloons that are passed through the catheter with an electrically insulating protective coating.   The ablation catheter with a balloon according to claim 11, wherein the electrically insulating protective coating of the lead wire for power supply is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride.   The ablation catheter with a balloon according to claim 11, wherein the electrically insulating protective coating of the sensor lead wire is made of a material having a relative dielectric constant smaller than that of polyvinyl chloride.   The ablation catheter with a balloon according to any one of claims 1 to 13, wherein a forced cooling mechanism for the catheter is not provided.   The ablation catheter with a balloon according to any one of claims 1 to 14, wherein a high-frequency power is supplied with a supply amount corresponding to a temperature measurement result of a temperature sensor and a liquid supply means for supplying a liquid into the balloon via the catheter. Ablation catheter with balloon comprising power supply means for supplying.   The ablation catheter with a balloon according to claim 15, wherein the liquid fed by the liquid feeding means passes through a clearance between the outer cylinder shaft and the inner cylinder shaft. The ablation catheter with a balloon according to claim 15 or 16, wherein the liquid in the balloon in an inflated state is moved in and out between the catheter and the balloon by the liquid fed by the liquid feeding means, and the liquid in the balloon is agitated. An ablation catheter with a balloon provided with liquid stirring means.

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