JP4062935B2 - Ablation catheter with balloon - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to an ablation catheter with a balloon, and a balloon for locally treating a lesion by inflating the balloon to closely adhere to a target lesion and performing high-frequency heating to treat cardiac arrhythmia, particularly atrial fibrillation. The present invention relates to an attached ablation catheter.
[0002]
[Prior art]
In recent years, a treatment method for electrocoagulating an arrhythmia source by bringing a metal electrode catheter made of a 4 mm-sized tip into contact with the arrhythmia source and applying high-frequency current has become widespread. However, this technique is relatively good when the source is local, such as WPW syndrome or paroxysmal ventricular tachycardia, but it has a wide range of dots or lines to treat atrial fibrillation and atrial flutter. The ablation was repeated several times and energized several tens of times, but the catheter was difficult to operate, and it was technically extremely difficult and unsuccessful.
[0003]
A conventional balloon catheter (Japanese Patent Laid-Open No. 2-68073, Japanese Patent No. 2574119) provided with a high-frequency heating electrode and a temperature sensor performs treatment on the whole heated balloon by applying high-frequency electricity. Japanese Patent No. 2574119 discloses an example of a balloon catheter that can cauterize a wide vascular wall of the pulmonary vein, and a large balloon that occupies the entire left atrium, and can simultaneously cauterize all four pulmonary vein openings by simultaneously contacting the balloon. However, ablation of the pulmonary vein wall may cause stenosis in the pulmonary vein and cause pulmonary hypertension, and cauterization using a large balloon occupying the entire left atrium Paused the heart Set , Need extracorporeal circulation using cardiopulmonary bypass But is there.
[0004]
A high-frequency hot balloon catheter (Kazushi Tanaka et al., “Journal of the American College of Cardiology”, 38 (7): 2079-86 (2001)) is easy and short around the pulmonary vein mouth. It is a catheter capable of ring cauterization over time. Since the pulmonary vein mouth can be cauterized, it is not necessary to perform cauterization as many times as a metal electrode catheter, and in order not to cauterize a wide range of pulmonary veins unlike the catheter described in Japanese Patent No. 2574119, restenosis There is no need to stop the heart to cauterize only one pulmonary vein opening.
[0005]
[Problems to be solved by the invention]
When the high-frequency balloon catheter is used for the treatment of atrial fibrillation, the balloon tip is inserted from the inferior vena cava, pierced through the right atrium, transseptally into the atrium, and guided into the left atrium. It is guided to the mouth and the affected area is cauterized. Although the balloon catheter has excellent performance as described above, since the materials and shapes constituting the balloon and the electrode do not necessarily meet this purpose, the blood vessel bifurcation and the atrium are guided at the time of guidance to the affected area. In some cases, it may be difficult to guide the balloon to the target site because it may get caught in an unintended site, and the ablation may not succeed because the balloon shape does not fit the pulmonary vein opening. . Because the shaft material has a high relative dielectric constant and low insulation, the cooling water is circulated and the inside of the catheter is cooled, but the shaft is softened and deformed due to overheating caused by high-frequency energization, and the balloon was pressed against the pulmonary vein opening However, if the balloon slides out of the pulmonary vein opening due to pulmonary venous pressure, or if the high frequency output is suppressed to suppress heating, the lesion will not be cauterized, resulting in undesirable effects such as repeated cauterization. Sometimes it happened. In addition, the temperature sensor provided in the balloon comes into contact with various parts in the balloon, which causes problems such as inability to accurately measure the temperature in the balloon. Further, the high-frequency balloon catheter needs to be perfused with cooling water for cooling the inside of the balloon, and since the tube for circulating the cooling water is built in the shaft, the shaft becomes thick and the operability of the catheter is increased. Was lowering.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has the following configuration.
[0007]
(1) A tube inserted into a blood vessel, a balloon attached to the tip of the tube and having a shape capable of contacting a target lesion in an expanded state, and an electrode for high-frequency energization disposed in the balloon The tube is a double tube tube that is concentrically pushed so as to be slidable in the axial direction, and the tip of the balloon is fixed to the tip of the inner tube, In the ablation catheter with a balloon in which the rear end of the balloon is fixed to the tip, the balloon includes a small diameter portion on the tip side, The ratio of the diameter of the large diameter portion of the balloon to the diameter of the small diameter portion on the tip side of the balloon in the expanded state is in the range of 5-12. The electrode for high-frequency energization is wound around the outer periphery of the inner tube in a coil shape, and the electrode is covered with a protective coating material electrically connected to the electrode for high-frequency energization A lead wire, a temperature sensor embedded in the electrode for high-frequency energization, a temperature sensor lead wire covered with a protective covering material connected to the temperature sensor, the electrode for high-frequency energization, and the temperature sensor are predetermined in the balloon. An ablation catheter with a balloon, comprising a fixing holder for fixing to a position.
[0010]
(4) The double tube tube is an ablation catheter with a balloon according to any one of (1) to (3), wherein both the inner tube and the outer tube are made of a plastic material having a relative dielectric constant smaller than that of polyvinyl chloride.
[0011]
( 2 The balloon is an ablation catheter with a balloon according to (1), wherein the balloon is made of a polyurethane polymer material, and the balloon thickness is in a range of 100 μm to 300 μm.
[0012]
( 3 ) The balloon has a balloon length in the range of 20 mm to 40 mm in the inflated state (1) Or (2) An ablation catheter with a balloon as described in 1.
[0014]
( 4 (1) to (1), comprising: a temperature monitoring mechanism for monitoring the temperature sensor; and a power supply mechanism for supplying high-frequency power so that the temperature of the balloon becomes a predetermined temperature. 3 Ablation catheter with a balloon according to any one of the above.
[0015]
( 5 (1) A radiation shielding metal pipe is fitted on the tip of the inner tube and the outer tube, and a balloon is mounted on the metal pipe. 4 Ablation catheter with a balloon according to any one of the above.
[0017]
( 6 (1) to (1) characterized by having no cooling means 5 Ablation catheter with a balloon according to any one of the above.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides a balloon having a small conical portion on the distal end side, and in the expanded state, the distal end is located at the distal end from the distal end of the inner tube, and the diameter gradually increases from the small diameter portion to the rear end. A lead wire coated with a protective coating material having a relative dielectric constant smaller than that of 6-nylon, 6,6-nylon, or polyvinyl chloride, electrically connected to the energizing electrode, and a temperature embedded in the high-frequency energizing electrode Sensor, lead wire coated with a protective coating smaller than 6-nylon, 6,6-nylon, polyvinyl chloride, connected to the temperature sensor, and the temperature sensor fixed in place in the balloon The present invention relates to an ablation catheter with a balloon provided with a fixed holding tool. The balloon constituting the present invention is not particularly limited as long as it has a high antithrombotic material, but a polyurethane-based polymer material is preferably used. Specifically, thermoplastic polyether polyurethane, polyether polyurethane urea, fluorine polyether polyurethane urea, polyether polyurethane urea resin, polyether polyurethane urea amide, and the like can be preferably used, but are not limited thereto. The shape of the balloon is such that it can contact the human pulmonary vein in a ring shape, and when it is deflated, it passes through the inferior vena cava, punctures from the right atrium to the left atrium, and leads to the pulmonary vein Those that are easy to operate in blood vessels are preferred. In particular, when the balloon is inflated with a small-diameter portion on the tip side, the balloon tip is at the tip from the tip of the inner tube, and the balloon has a right cone shape whose diameter gradually increases from the small-diameter portion to the rear end of the balloon. Such a shape is preferably used. In the present invention, the balloon small diameter portion refers to a portion having the smallest diameter when the balloon is inflated to the maximum, and the balloon large diameter portion refers to a portion having the largest diameter when the balloon is inflated to the maximum. . By making the balloon tip more distal than the inner tube tip, the inner wall surface of the blood vessel or the inner wall surface of the heart can be prevented from being damaged at the tip of the catheter. Also, if the balloon has a right conical shape, for example, if a lesion at the junction of the pulmonary vein and the left atrial wall is present in a ring shape at the pulmonary vein mouth, the right conical balloon will come out of the pulmonary vein. This is because the lesion can be contacted without any problem. When the balloon is inflated, the ratio of the diameter of the large-diameter portion of the balloon to the diameter of the small-diameter portion of the balloon tip is 5 to 12 in order to cope with a mortar-shaped lesion. preferable. The length of the balloon is preferably 20 to 40 mm in consideration of operability and the like for operation in the atria and ventricles. The thickness of the balloon is not particularly limited as long as it can be easily induced in the blood vessel and inflated and cauterized in the pulmonary vein, and the shape upon expansion is constant. In order to hold the balloon, the thickness of the balloon is preferably 100 μm or more, and in order to make the balloon have sufficient stretchability, the thickness is preferably 300 μm or less.
[0019]
The tube constituting the present invention is not particularly limited as long as it is made of a material having high antithrombotic properties in blood vessels, but a plastic material having a relative dielectric constant smaller than that of polyester polyurethane elastomer, polyethylene terephthalate, or vinyl chloride resin is preferable. The relative dielectric constant can be measured by the following method.
[0020]
ε = Cx / Co
ε: dielectric constant
Cx: Capacitance of the measuring capacitor Cs when the bridge is balanced
Co: Calculated by the following equation with the capacitance of ε = 1 calculated from the area of the main electrode and the thickness of the test piece.
[0021]
Co = r ² /3.6t
r: radius of main electrode (cm)
t: thickness of test specimen (cm)
A test piece is mounted on a dielectric material measurement electrode (HP16453A) installed in a thermostat, and the frequency is measured using an RF impedance / material analyzer (HP4291A, Hewlett-Packard) while maintaining the electrode and the sample plate at a predetermined temperature. Ε (relative permittivity) at 10 to 200 MHz and an applied voltage of 500 mV is measured.
The test piece used is dried at 60 ° C. for 2 days under reduced pressure (about 8 KPa).
[0022]
The tube inserted into the blood vessel is an electrode for high-frequency energization from In order to mitigate overheating caused by high frequency, it is preferable to use a material having a relative dielectric constant lower than that of polyester polyurethane elastomer, polyethylene terephthalate, or vinyl chloride resin, and the measured value at a relative dielectric constant of 10 MHz is 5 or less. Things Preferably 3 or less is more preferable, 1.23 or less is particularly preferable, and 1 or less is more preferable. By using a material having a relative dielectric constant lower than that of polyester polyurethane elastomer, polyethylene terephthalate, 6-nylon, and 6,6-nylon, the cooling means required in the conventional product can be omitted, and the entire tube is made thin. Therefore, the operability of the catheter is improved. As a plastic material whose dielectric constant is lower than that of polyester polyurethane elastomer, polyethylene terephthalate, 6-nylon, 6,6 nylon, and vinyl chloride resin, fluororesin (polytetrafluoroethylene resin, tetrafluoroethylene-6-fluoropropylene-6 Copolymer resin, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer resin), polyethylene, polyimide resin, polyamide resin, thermoplastic elastomer (polyamide, styrene, olefin), polypropylene, methylpentene, etc. are preferred, However, the present invention is not limited to these materials. As shown in FIG. 1, the distal end of the tube is attached with the balloon having a shape capable of contacting the target lesion in an expanded state, and the tubes are slidable in the axial direction. In addition, it is a double tube tube that is concentrically pushed through, and the tip of the balloon is fixed to the tip of the inner tube, and the rear end of the balloon is fixed to the tip of the outer tube. Yes. The shape of the balloon attached to the tip can be variously changed by sliding the double-tube tube that is concentrically pushed so as to be slidable in the axial direction.
[0023]
Moreover, it is preferable that a radiation shielding metal pipe is fitted to the distal end portion of the tube, and it is preferable that each end of the balloon is mounted on the metal pipe, and by providing the metal pipe. The metal pipes corresponding to both ends of the balloon can be clearly projected on the fluoroscopic image by X-rays. The radioactive shielding metal pipe referred to here may be any metal having low permeability to various ionizing radiations, and specifically, gold, platinum, stainless steel, TI-NI alloy, etc. can be used. It is not limited.
[0024]
The high-frequency energizing electrode constituting the present invention is not particularly limited as long as it can be used for the purpose of generating a high frequency when the affected area is cauterized and heating the inside of the balloon. The high frequency used at the time of balloon ablation (cautery) is preferably 1 MHz to 40 MHz, particularly preferably 13.56 MHz for medical use, and a material and shape capable of emitting a high frequency that also uses a high-frequency energizing electrode are preferable. .
[0025]
The lead wire constituting the present invention is not particularly limited as long as it is connected to the electrode for high-frequency energization and can be used for the purpose of delivering high-frequency to the electrode, but does not generate heat when energized with a high-frequency signal, Those composed of a material without energy loss are preferred. The lead wire is coated with a protective coating material, and the protective coating material preferably has a relative dielectric constant lower than that of polyvinyl chloride, 6-nylon, 6,6-nylon, and polyurethane, when measured at 10 MHz. Value of 5 or less More preferable It is further preferably 2.5 or less, particularly preferably 1.23 or less, and further preferably 1 or less. If the coating material has a high dielectric constant, it is necessary to perfuse the cooling water in the catheter in order to suppress overheating caused by the high-frequency current-carrying electrode, and a perfusion channel is required, and the entire tube is thick. As a result, the operability of the catheter is reduced. In addition, the protective covering material is particularly preferable in order to stabilize the electrical characteristics when it has a high insulating property. As the protective coating material, materials such as fluororesin (PTFE, FEP, PFA), polyethylene, polystyrene, polyurethane and the like can be used, but the material is not particularly limited thereto.
[0026]
The temperature sensor constituting the present invention is not particularly limited as long as it can be used for the purpose of measuring the temperature in the balloon, but is preferably a thermocouple, and the measurement data from the temperature sensor is monitored. The output of the high frequency generator that supplies power to the high frequency energizing electrode is fed back as temperature data.
[0027]
The lead wire connected to the temperature sensor constituting the present invention is not particularly limited as long as it is a conductor that can be used to deliver a signal for monitoring the temperature inside the balloon to the outside of the balloon, but platinum, tungsten, copper, Alloys, such as chromel are preferred. Further, the lead wire connected to the temperature sensor is preferably coated with a protective coating material in order to prevent a short circuit with the lead wire connected to the high-frequency energizing electrode in the tube, and the protective coating material is The dielectric constant is preferably lower than that of polyvinyl chloride, the dielectric constant at 10 MHz is more preferably 2.5 or less, particularly preferably 1.23 or less, and more preferably 1 or less. In order to suppress overheating caused by the electrode for high-frequency energization with a protective coating material having a high relative dielectric constant, it is necessary to perfuse the cooling water in the catheter, a perfusion channel is required, and the entire tube It becomes thick and the operability of the catheter is reduced. In addition, the protective coating material is particularly preferable in order to stabilize electrical characteristics when the insulating coating material has high insulating properties. As the protective coating material, materials such as fluororesin (PTFE, FEP, PFA), polyethylene, polystyrene, polyurethane and the like can be used, but the material is not particularly limited thereto.
[0028]
The fixing holder constituting the present invention is: The high-frequency energizing electrode and Although it will not specifically limit if it can be used in order to fix the said temperature sensor in the predetermined position in a balloon, The thing using a clip and a band shape plastic and an aramid fiber as a raw material is preferable for the reason of weight reduction and size reduction. The fixed holder enables accurate heating and temperature monitoring without moving from the initial setting positions of the high-frequency energizing electrode and the temperature sensor even if the balloon is repeatedly expanded or expanded and contracted.
[0029]
One embodiment of an ablation catheter with a balloon according to the present invention is shown in FIG. 1 (overall view of the balloon).
[0030]
As shown in FIG. 1, the balloon catheter is a contraction / expansion placed between a double tube composed of an outer tube 4 and an inner tube 3, and the distal end portion of the outer tube 4 and the vicinity of the distal end portion of the inner tube 3. A possible balloon 1, a high-frequency energizing electrode 8 disposed in the balloon 1, an electrode lead 8 a electrically connected to the high-frequency energizing electrode 8, and a balloon 1 for monitoring the temperature in the balloon 1 A temperature sensor 9 disposed therein and a temperature sensor lead wire 9 a electrically connected to the temperature sensor 9 are provided. The balloon 1 is formed of an antithrombogenic polyurethane polymer material having a smooth surface. As shown in FIG. 1, the balloon 1 has a right-cone-shaped cross section with the side close to the outer tube 4 as the upper side, and a predetermined portion of a single pulmonary vein opening 20 in an expanded state, for example, a pulmonary vein 22 and the left shoulder wall 24 have a shape that can be contacted in a ring shape. A high frequency energizing electrode 8 is wound around the outer periphery of the inner tube 3 in the balloon 4 in a coil shape. The outer tube 4 is made of an anti-thrombogenic polyurethane polymer material having a radiopaque and smooth surface.
[0031]
As shown in FIG. 3, the electrode lead wire 8a connected to the high frequency energizing electrode 8 passes between the inner side of the outer tube 4 and the outer side of the inner tube 3, and can supply high frequency power of 13.56 MHz, for example. The high frequency generator 30 is connected. Moreover, the counter electrode installed in the patient's body surface, for example, the position of the back, is connected to the high frequency generator 30 via the lead wire. By the high frequency generator 30, a high frequency electric current is provided between the high frequency energizing electrode 8 and the counter electrode plate. Power Is supplied. For example, the diameter of the balloon 1 is about 2 . In the case of 5 cm, high frequency power of 50 W to 200 W Power Is supplied.
[0032]
As a result, The inside and surface of the balloon are heated by Joule heat generated by the diluted contrast agent filled in the balloon, As shown in FIG. 1, the joint part 26 which contacts the balloon 1 is heated in a ring shape and cauterized. Only the pulmonary vein port 20 of a single pulmonary vein 22 is selectively electrically isolated from the left atrium by the heated transfusion junction 26. Here, in spite of the high frequency energization with the large output high frequency generator 30, the heat generated by the electrode lead wire 8a is caused by making the relative permittivity of the protective covering material of the electrode lead wire lower than that of polyvinyl chloride. Can be reduced.
[0033]
The temperature in the balloon 1 is monitored by the temperature sensor 9 via a thermometer, and the high frequency power supplied by the high frequency generator 30 passes through a feedback circuit so that the temperature in the balloon 1 is 60 ° C. to 70 ° C. Adjusted. As a result, the temperature of the joint portion 26 is maintained at the optimum 60 ° C. to 70 ° C., and carbonization of the tissue and thrombus formation can be prevented.
[0034]
The high-frequency generator 30 has a function of monitoring the impedance between the high-frequency energizing electrode 8 and the counter electrode plate, and the impedance between the high-frequency energizing electrode 8 and the counter electrode plate. value The application time of the high frequency power is controlled so that is in a predetermined range. As a result, it is possible to control the range of the area where the joint 26 is heated. Also, when this impedance suddenly rises, Power The high-frequency generator 30 is equipped with a safety device so that the supply of power stops instantaneously.
[0035]
【Example】
Concentration of 13% in a balloon mold having a large diameter part (1a) of 30 mm of the balloon 1, a diameter of 3 mm of the tip part (1b) of the balloon 1, and a balloon length of 30 mm In Balloon 1 was manufactured by a dipping method in which the prepared polyurethane solution was immersed and the solvent was evaporated by applying heat to form a urethane polymer film on the mold surface. The resulting balloon 1 is r as shown in FIG. ₁ Is 30mm, r ₂ Was 3 mm, the ratio of the diameter of the large diameter portion to the small diameter portion was 10, and the balloon length h was 30 mm, which was the same size as the molding die.
The urethane polymer film d was a film having a uniform thickness of 160 μm. The polyurethane in the polyurethane solution was a blend of 15% diphenylmethane diisocyanate (MDI), 70% polyoxytetramethylene glycol (PTMG), and 15% ethylenediamine.
[0036]
On the other hand, a polyamide tube having a diameter of 1.2 mm, a length of 6 mm and a sandblasted outer surface is used as the inner tube 3, and a stainless steel pipe 5 having a diameter of 1.2 mm and a total length of 900 mm is inserted into the tip. A 0.1 mm nylon thread T is tied and fixed with a 0.1 mm nylon thread T, and a 0.1 G nylon thread T is inserted into the rear end by inserting a 16 G length 90 mm needle-attached stainless steel pipe (wicking needle) 12 into the rear end. I tied it with and fixed it.
[0037]
On the other hand, a polyamide elastomer (trade name; Pebax grade: 6333) tube containing 12% Fr · 800 mm of barium sulfate and having a diameter of 2.8 mm, a length of 7 mm and a sandblasted outer surface is used as the outer tube 4. The pipe is made of metal pipe 6 and fixed at the front end with 0.1 mm nylon thread T and fixed, and the W connector 11 is inserted at the rear end and fixed with 0.1 mm nylon thread T and fixed. .
[0038]
Then, the inner tube 3 was inserted through the W connector 11 and the W connector cap 13 was tightened to obtain the double tube 2.
[0039]
In addition, 0.5 mm electric annealed copper wire with a silver plating thickness of 0.1 μm or more is coiled with an inner diameter of 1.6 mm and a length of 10 mm, and a tetrafluoroethylene-6fluoropropylene copolymer resin over a length of 1000 mm (FEP) was coated to produce an electrode coil 8 and a lead wire 8a.
[0040]
In addition, an ultrafine thermocouple double (copper-constantan) wire covered with polytetrafluoroethylene (PTFE) is embedded in the electrode coil 8 as a temperature sensor 9, and then the electrode coil 8 and the temperature sensor are connected to the tip of the inner tube 3. The lead wires 8a and 9a are pulled out from the W connector 11, and the lead wires 8a and 9a are joined to the metal pipe 6 by a fixture 10 made of aramid fiber, thereby positioning the electrode coil 8 and the temperature sensor. .
[0041]
Next, the tip 1A of the balloon 1 and a polyurethane thin tube as the tip 7 are placed on the tip of the metal pipe 5 and fixed with a nylon thread T having a thickness of 0.1 mm, and the rear end of the balloon 1 is fixed. After 1B was put on the tip of the metal pipe 6 and fixed with a nylon thread T having a thickness of 0.1 mm, each was smoothly finished with an epoxy resin adhesive H to produce an ablation catheter with a balloon.
[0042]
Next, the function of the ablation catheter in the catheter of this example was checked as follows. First, the two-way stopcock 14 and the three-way stopcock 16 cock connected to the W connector 11 are opened, and the diluted contrast agent is injected from the two-way stopcock 14 so that the diameter of the large diameter portion of the balloon 1 becomes 30 mm. The two-way stopcock 14 and the three-way stopcock 16 cock were closed. The high frequency generator 30 is connected to the high frequency energizing electrode lead wire 8a terminal and the temperature sensor lead wire 9a terminal from the Y connector 15, and the pork block having a 20mm diameter hole as a phantom (pseudo living body) After confirming that the balloon 1 having a diameter of 30 mm in diameter was inserted and fitted into a 20 mm hole, the balloon internal temperature was set to 60 ° C., and high-frequency energization was started at an output of 10 W. After 1 minute, the output was gradually increased, and after 1 minute 20 seconds, the temperature in the balloon reached 60 ° C., and the output was also controlled between 20 W and 40 W. After 5 minutes of high-frequency energization, the energization was stopped, the phantom was removed from the balloon 1 and the portion that was in contact with the balloon 1 was observed, and the red pigment was whitened in a ring shape and ablation was sufficiently performed.
[0043]
Subsequently, an animal experiment example using the ablation catheter with a balloon according to the present invention for pigs will be described. First, an incision was made in the femoral vein of a pig weighing 46 kg under anesthesia, the atrial septum was punctured with an atrial septal puncture needle while confirming the atrial septal site by echocardiography, and the atrial septal puncture catheter was left behind. The septal puncture needle was removed. A pigtail guidewire was introduced into the left atrium through the atrial septal puncture catheter. Through this, the sheath with 14Fr dilator was introduced into the left atrium, and the dilator and the picktail guide wire were pulled out from the sheath. Another 0.025 inch guide wire was inserted into the left upper pulmonary vein and the sheath tip was pushed into the left upper pulmonary vein position.
[0044]
Next, it is inserted into a 0.025 inch guide wire from the distal end side of the tube in the catheter from which air has been evacuated in advance, and when the entire catheter enters the 0.025 inch guide wire, the suction needle 12 is inserted into the W connector cap 13. (The balloon part is extended). After the balloon was stretched, the position of the balloon 1 was confirmed accurately by X-ray fluoroscopy using the images of the metal pipes 5 and 6 as a guide, and the catheter was pushed into the upper left pulmonary vein along the sheath. . (The metal pipes 5 and 6 have X-ray shielding properties and are clearly visible at the time of X-ray fluoroscopy, so that the position of the balloon 1 can be accurately grasped. The ) When it was confirmed that the balloon 1 reached the target left upper pulmonary vein opening, the lock that had screwed the suction needle 12 into the W connector cap 13 was released.
[0045]
The contrast medium was injected from the three-way cock 16 and the balloon 1 was inflated. After confirming that the balloon is in contact with the pulmonary vein opening by fluoroscopy, the guide wire is pulled out, the contrast medium is poured from the suction needle 12, and the pulmonary vein opening and the balloon 1 are completely adhered to each other by the balloon 1. It was confirmed under fluoroscopy that no leaking into the left atrium.
[0046]
After confirming that there was no leakage of pulmonary venous blood, the electrode lead wire 8a terminal and the temperature sensor lead wire 9a terminal extending from the catheter proximal portion Y connector 15 were connected to the high frequency generator 30. The counter electrode was attached to the pig's back, and the high frequency generator 30 was activated. The temperature inside the balloon 1 was controlled at an output of 30 to 60 W for 5 minutes and the energization was stopped after cauterizing the left upper pulmonary vein mouth.
[0047]
Subsequently, the contrast medium of the balloon 1 was extracted from the three-way cock 16 and the balloon 1 was deflated, and a 0.025 inch guide wire was inserted into the catheter. When the 0.025 inch guide wire came out of the catheter tip, the suction needle 12 was screwed into the W connector cap 13 and locked. When the balloon 1 was extended, the catheter was removed from the body, and the lock that screwed the suction needle 12 into the W connector cap 13 was released.
[0048]
Next, a 0.025 inch guide wire in the left atrium was inserted into the right upper pulmonary vein, and the orientation of the sheath tip was changed to the right upper pulmonary vein opening. The catheter taken out from the body again was inserted into a 0.025 inch guide wire, and when the entire catheter entered the guide wire, the suction needle 12 was screwed into the W connector cap 13 and locked (the balloon portion was expanded). After the balloon portion is stretched, the catheter is pushed along the sheath to the upper right pulmonary vein opening, and the subsequent operation is the same as the procedure for cauterizing the left upper pulmonary vein opening. Similar to the left upper pulmonary vein ablation, the temperature in the balloon 1 was continuously controlled at an output of 30 to 60 W for 5 minutes, and high-frequency energization was stopped after cauterizing the upper right pulmonary vein opening.
[0049]
The performance of the catheter taken out of the body was checked after use, but the double tube 2 and balloon 1 maintained the same shape as before the experiment, and no deformation due to heat generation due to high-frequency energization was observed. It was confirmed that the plastic material can be used for catheters.
[0050]
In addition, the carcasses of the pigs used in the experiment were dissected and the heart was necropsied, and it was confirmed that the junction between the left and right pulmonary veins and the left atrium was cauterized. Histologically, pulmonary vein myocardium was stained, coagulative necrosis in the pulmonary vein mouth wall was observed, and high-frequency energization was performed through the balloon, so that the pulmonary vein mouth could be safely and easily ablated. .
[0051]
【The invention's effect】
As described above, according to the configuration of the present invention, in the pulmonary vein electrical isolation treatment using the ablation catheter with a balloon, the operation at the time of guiding the catheter to the pulmonary vein opening found in the conventional product is performed. sex By reducing thrombosis and the occurrence of thrombus during ablation, rapid and safe treatment has become possible. In addition, the use of a material with a relative dielectric constant lower than that of polyester polyurethane elastomer, 6-nylon, 6,6-nylon, polyethylene terephthalate, and vinyl chloride resin eliminates the need for a cooling device as in conventional products and makes the catheter thinner. As a result, the operability during treatment has been greatly improved. Also temperature sensor - With the configuration of the present invention, even if the balloon is expanded or repeatedly expanded and contracted, accurate temperature monitoring can be performed without moving from the initial setting positions of the high-frequency energizing electrode and temperature sensor Na It was. Further, by adopting the configuration of the balloon according to the present invention, it is possible to prevent the inner wall surface of the blood vessel or the inner wall surface of the heart from being damaged at the distal end of the catheter, and it is possible to contact the lesioned part without detaching from the pulmonary vein. It became possible to deal with the lesions that are shaped like this.
[Brief description of the drawings]
FIG. 1 is a sectional view showing a use state of an ablation catheter with a balloon according to the present invention and showing a state in which a balloon is inflated.
FIG. 2 is a diagram showing a shape when a balloon is inflated.
FIG. 3 is a diagram showing one aspect of a balloon operation portion and one aspect when a balloon is extended.
[Explanation of symbols]
1 Balloon
1A Balloon tip
1B Balloon rear end
1a Large diameter part
1b Small diameter part
2 Double tube
3 Inner tube
4 Outer tube
5 Metal pipe
6 Metal pipe
7 Tip
8 Electrode for high frequency current
8a Electrode lead wire
9 Temperature sensor
9a Temperature sensor lead wire
10 Fixed holder
11 W connector
12 Suction needle
13 W connector cap
14 Two-way stopcock
15 Y connector
16 Three-way stopcock
20 Pulmonary vein mouth
22 Pulmonary veins
24 left atrial wall
26 joints
30 High frequency generator
400 An ablation catheter with a balloon in a state where the balloon is inflated.
500 This is the vicinity of the balloon of the ablation catheter with balloon in a state where the balloon is expanded.
600 This is an operation part of an ablation catheter with a balloon in which a suction needle is screwed into a connector cap.
d Balloon thickness
r ₁ Diameter of large diameter part
r ₂ Diameter of small diameter part
h Balloon height

Claims (6)

A tube to be inserted into a blood vessel, a balloon having a shape capable of contacting a target lesion in an expanded state attached to a distal end of the tube, and a high-frequency energizing electrode disposed in the balloon, The tube is a double tube type tube that is concentrically pushed so as to be slidable in the axial direction. The tip of the balloon is fixed to the tip of the inner tube, and the tip of the outer tube is In the ablation catheter with a balloon in which the rear end of the balloon is fixed, the balloon includes a small diameter portion on a distal end side thereof, and in a state where the balloon is inflated, the diameter of the balloon large diameter portion and the diameter of the small diameter portion on the balloon front end the ratio is characterized by a range of 5 to 12, the high frequency current applying electrode is characterized by being wound in a coil on the outer periphery of the inner tube, the high circumferential An electrode lead wire coated with a protective coating electrically connected to the energizing electrode, a temperature sensor embedded in the high frequency energizing electrode, and a temperature coated with the protective coating connected to the temperature sensor An ablation catheter with a balloon comprising a sensor lead wire, a high-frequency energizing electrode, and a fixing holder for fixing the temperature sensor at a predetermined position in the balloon. The ablation catheter with a balloon according to claim 1, wherein the balloon is made of a polyurethane-based polymer material and has a balloon thickness in a range of 100 μm to 300 μm. The ablation catheter with a balloon according to claim 1 or 2 , wherein the balloon has a balloon length in a range of 20 mm to 40 mm in an inflated state. The balloon according to any one of claims 1 to 3 , further comprising: a temperature monitoring mechanism that monitors the temperature sensor; and a power supply mechanism that supplies high-frequency power so that the temperature of the balloon becomes a predetermined temperature. Ablation catheter. Radiation shielding metallic pipes have been fitted to the tip portion of the inner tube and the outer tube, the balloon according to any one of claims 1 to 4, characterized in that mounted on the metal pipe Ablation catheter with balloon. The ablation catheter with a balloon according to any one of claims 1 to 5 , which does not have a cooling means.

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