JP7290335B2 - High frequency hot balloon catheter system - Google Patents

Description

The present invention relates to radiofrequency hot balloon catheter systems for radiating radiofrequency electric fields to adequately warm and treat target tissue in contact with the balloon.

Many cases of atrial fibrillation (AF) are known to be caused by myocardial sleeves in the pulmonary veins, and isolation of the pulmonary veins (PV) by ablation using a balloon catheter has been widely performed as a definitive treatment for AF, with good results. ing. At this time, the pulmonary vein potential (PVP) is monitored by the diagnostic annular electrode, and the pulmonary vein isolation is determined based on the disappearance of the potential.

There is a method of monitoring the pulmonary vein potential using a very fine annular electrode catheter (Lasso type) that passes through the inner cylinder of a balloon catheter and is deployed in the pulmonary vein. FIG. 1 shows the essential configuration of a conventional electrode catheter ablation system that implements the method. In the same figure, 100 is a balloon catheter including an outer tube 101, an inner tube 102, and a balloon 104. The elastic balloon 104 is located on the distal side of the tip of the balloon catheter 100 and is slidable relative to the outer tube 101 and the inner tube. It is installed between the tube 102 so as to be able to contract and expand. A high-frequency electrode 105 and a temperature sensor 106 are installed inside the balloon 104 , while a very fine annular electrode 107 passes through the interior of the hollow inner cylinder 102 and protrudes from the tip of the inner cylinder 102 . is installed.

In the ablation using the balloon catheter 100 shown in FIG. A high-frequency current is applied to the electrodes 105 to heat the filling liquid in the balloon 104, and at the same time, vibration waves are sent into the balloon 104 to agitate the filling liquid and uniformize the temperature of the balloon membrane to, for example, 70°C. The balloon membrane is brought into contact with the target site S of the pulmonary vein perioral tissue, and the target site S is thermally ablated all around and transmurally by heat conduction, aiming at pulmonary vein isolation. At this time, the progress of the ablation is estimated by monitoring the temperature of the balloon 104 and the pulmonary vein potential using the temperature sensor 103 installed in the balloon 104 and the electrode 107 installed at the tip of the balloon catheter 100. .

In addition, the applicant of the present application has proposed in Patent Document 1 a method of isolating pulmonary veins while monitoring the pulmonary vein potential by attaching a multipolar electrode to the tip of a balloon ablation catheter. FIG. 2A shows the essential configuration of a conventional electrode catheter ablation system that implements the method. In the same figure, the balloon catheter 200 also has a structure in which an elastic balloon 204 is installed in a contractible and expansible manner between an outer cylinder 201 and an inner cylinder 202 that are slidable on each other on the distal side of the tip of the balloon catheter 200. have A high-frequency electrode 205 and a temperature sensor 206 are installed inside the balloon 204 . Also here, a guide wire 207 that passes through the interior of the hollow inner cylinder 202 and protrudes from the distal end of the inner cylinder 202 is attached to the balloon-adjacent portion of the inner cylinder 202 that is close to the front end of the balloon 204 . , and a monitoring electrode 208 capable of monitoring an electrical state such as an electric potential in the vicinity of the target site S with the balloon 204 inflated.

The monitor electrode 208 is arranged around the outer side of the inner cylinder 202, and when released from the restricted state in the guide sheath 209, the wire member 211 that can be deployed in a direction perpendicular to the axis of the inner cylinder 202, and each and an electrode part 212 attached to the wire member 211 and detecting a potential in the vicinity of the target site S. A rear electrode holding portion 213 is fixedly provided at a portion of the inner cylinder 202 at the front end portion of the balloon 204 , and the rear electrode holding portion 213 is attached to the rear end portion of the wire member 211 and electrically connected. It is formed to be insulative and provided outside the balloon 204 so as to be in contact with the balloon 204 . An electrically insulating front electrode holding portion 214 separate from the rear electrode holding portion 213 is provided in the inner cylinder 202 on the front side of the rear electrode holding portion 213 so as to be slidable in the axial direction of the inner cylinder 202 . ing. A front end portion of the wire member 211 is attached to the front electrode holding portion 214 .

Ablation using the balloon catheter 200 shown in FIG. 2A is also performed by expanding the balloon 204 with an electrolyte solution and crimping it to the pulmonary vein ostium, and applying a high-frequency current to the electrode 205 inside the balloon 204 to heat the filling liquid inside the balloon 204. At the same time, an oscillating wave is sent into the balloon 204 to agitate the filling liquid and homogenize the temperature of the balloon membrane. The balloon membrane is brought into contact with the target site S of the pulmonary vein perioral tissue, and the target site S is thermally ablated all around and transmurally by heat conduction, aiming at pulmonary vein isolation. Here, when the monitor electrode 208 is pulled out of the guide sheath 209, the front electrode holding portion 214 slides rearward and the wire member 211 develops in an arc shape. In this state, as shown in FIG. 2A, the electrode part 212 in the central part of the wire member 211 is brought into contact with the vicinity of the target site S, and by detecting the potential there, the target site S being cauterized by the balloon 204 is detected. It becomes possible to grasp the electrical state such as the potential of

FIG. 2B shows the essential configuration of another electrode catheter ablation system proposed in Patent Literature 1. Components common to those in FIG. 2A are denoted by the same reference numerals, and description thereof will be omitted as much as possible. The monitor electrodes 228 here are composed of wire members 231 that can be rotated in a direction orthogonal to the axis of the inner cylinder 202 when released from the restrained state in the guide sheath 209, and the distal ends of the respective wire members 231. and a spherical electrode portion 232 attached to detect the potential in the vicinity of the target site S. The rear electrode holding portion 213 is provided inside the balloon 204 so as to be in contact with the balloon 204 and fixed to the inner cylinder 202 . In the wire member 231 of the monitor electrode 228, the rear end is attached to the rear electrode holding portion 213, and the front end is formed as a free end. When the wire member 231 is released from the restricted state in the guide sheath 209, the wire member 231 expands in a bell shape, and the electrode portion 232 attached to the free end of the wire member 231 contacts the vicinity of the target site S, and the potential there is increased. It is designed to detect

JP 2012-095853 A

However, in the conventional method shown in FIG. 1, if the lumen of the inner tube 102 is occupied by the annular electrode 107 serving as a diagnostic catheter, the guide wire cannot be inserted, making it difficult to hold the expanded balloon 104 at the pulmonary vein ostium. , there is a drawback that the efficiency of ablation is lowered.

On the other hand, the loss of pulmonary vein potential during ablation using the method of US Pat. However, if the monitoring electrodes 208 and 228, which are the tip electrodes, are not in close contact with the inner wall of the pulmonary vein, the pulmonary vein potential cannot be accurately recorded, so the electrodes must be shaped like a basket or a bell ( 2A, 2B). For this reason, the production is troublesome, and if the monitor electrodes 208 and 228 having such a shape are attached to the tip of the balloon catheter 200, the operation becomes difficult, and if the operation is erroneous, it may be damaged, and part of the parts may fly off to cause embolism. There is also a possibility of causing it, and there is a problem with safety.

Therefore, in view of the above problems, the inventors devised an invention in which a simple bipolar electrode is attached to the tip of a balloon ablation catheter. As a result, it is possible to monitor the pulmonary vein potential with the balloon tip electrode while ablating the pulmonary vein ostium circumferentially with the balloon using a single catheter. However, there is often a distance between the balloon tip electrode and the inner wall of the pulmonary vein, making it difficult to determine pulmonary venous potential loss when the pulmonary venous potential is ambiguous. In some cases, the myocardial sleeve is developed near the ostia of the pulmonary vein, but not distal to the pulmonary vein. If the myocardial sleeve is poorly developed, the electromotive force is small and the pulmonary venous potential is also small. However, even such a small myocardial sleeve is connected to the atrial muscle and can be a source of arrhythmia.

Therefore, in the present invention, the myocardial sleeve in the pulmonary vein is electrically stimulated (pulmonary vein pacing) from the balloon tip electrode during ablation, and the excitation wave is transmitted to the atrium and the atrium is excited. We devised a high-frequency hot balloon catheter system in which the loss of entrapment is used as an indicator of pulmonary vein isolation. At this time, the tip electrode should be a bipolar electrode, and the rear proximal electrode should be close to the balloon membrane so that pulmonary venous pacing can be performed even if the balloon tip electrode is not in contact with the pulmonary vein wall and is separated from the pulmonary vein wall. brought close to At the same time, the distance between the bipolar electrodes at the tip is 2 to 5 mm, preferably 2.5 to 5 mm, and the pulse width is wide (5 to 30 milliseconds, preferably 10 to 30 milliseconds) and output as electrical stimulation. A large one (5-100 mA, preferably 10-100 mA) was used. For this purpose, a dedicated high-output cardiac electrical stimulator was created. Even if the bipolar electrode at the tip of the balloon and the inner wall of the pulmonary vein are separated, the strong stimulation current from this electrical stimulator fills the electrical capacity of the blood that exists between them, and then conducts to the myocardial sleeve on the inner wall of the pulmonary vein. can excite this. Therefore, even when the bipolar electrode at the tip of the balloon and the inner wall of the pulmonary vein are distant and the pulmonary vein potential is unclear, pulmonary vein pacing is possible.

That is, in the invention of claim 1, an elastic balloon is installed between an outer cylinder and an inner cylinder that are slidable relative to each other, and a bipolar electrode is installed at the tip of the inner cylinder in close proximity to the balloon film surface. , the bipolar electrode is connected to an extracorporeal intracardiac electrocardiograph and an electrical stimulator through a first conducting wire; a high-frequency conducting electrode and a temperature sensor are installed in the balloon; and the temperature sensor are connected to an extracorporeal high-frequency generator and a thermometer by a second electric wire, and a liquid feeding path leading to the balloon is formed between the outer cylinder and the inner cylinder, The high-frequency hot balloon catheter system is characterized in that one of the fluid passages is connected to the inside of the balloon, and the other is connected to a syringe for injecting and aspirating the fluid into the balloon and an extracorporeal vibration generator.

In the invention according to claim 2, the bipolar electrodes are close to the balloon membrane, each of which is a good electrical conductor such as gold, silver, copper or platinum and has a ring shape, a ring width of 1.5 to 3 mm, and an inner diameter. 2 to 5 mm.

In the invention of claim 3, the bipolar electrode is composed of a proximal electrode and a distal electrode, and the proximal electrode is installed at a position close to the balloon membrane surface at a distance of 0.5 to 2.0 mm, The distal electrode is placed at a distance of 2 to 5 mm distal to the proximal electrode.

According to the fourth aspect of the invention, the electrical stimulator has an output of 5 to 100 milliamperes, a pulse width of 5 to 30 milliseconds, and enables continuous pacing at a rate of 60 to 150 per minute.

In the first aspect of the present invention, a bipolar electrode is installed at the distal end of the inner cylinder in close proximity to the balloon membrane surface, and this bipolar electrode is connected to the intracardiac electrocardiograph via the first conducting wire. By providing a bipolar electrode at the tip of the balloon, the pulmonary vein potential can be recorded on an intracardiac electrocardiograph via blood, which has relatively good conductivity, and the progress of pulmonary vein isolation by ablation can be confirmed. . Furthermore, since the bipolar electrodes are connected to the electrical stimulator via the first conductive line, even if the disappearance of the pulmonary venous potential due to pulmonary vein isolation is not apparent, the atrium associated with pulmonary vein pacing using the electrical stimulator can be detected. By confirming the presence or absence of capture with an intracardiac electrocardiograph, the progress of pulmonary vein isolation can be monitored with high accuracy.

In the invention according to claim 2, the bipolar electrode adjacent to the balloon membrane surface is made of a good electrical conductor such as gold, silver, copper or platinum and has a ring shape. 5 millimeters. Therefore, the electrical potential of the myocardial tissue can be sensed with high sensitivity, and it can be adapted to the use of electrical stimulation with a wide pulse width and high intensity.

In the third aspect of the present invention, the bipolar electrode is composed of a proximal electrode and a distal electrode, and the proximal electrode is installed at a position close to the balloon membrane surface at a distance of 0.5 to 2.0 mm. Therefore, the pulmonary vein potential can be monitored and the pulmonary vein pacing can be performed by bringing the device close to the pulmonary vein ostium where the myocardial sleeve is developed. In addition, the distal electrode is placed 2 to 5 mm farther than the proximal electrode, so that pulmonary vein pacing can be performed even if the bipolar electrode at the tip of the balloon does not contact the wall of the pulmonary vein. can be done without problems.

In the invention of claim 4, the output intensity of the electrical stimulator is 5 to 100 milliamperes (mA) and the output pulse width is 5 to 30 milliseconds (ms), so that the bipolar electrode at the tip of the balloon comes into contact with the pulmonary vein wall. Since pulmonary venous pacing can be performed appropriately even if the patient is away from the patient, it is possible to adopt a simple bipolar electrode as the electrode structure used for pulmonary venous pacing and pulmonary venous potential measurement.

FIG. 10 is an explanatory view showing the essential configuration of a conventional electrode catheter ablation system having Lasso-type electrodes; FIG. 10 is an explanatory view showing the main configuration of a conventional electrode catheter ablation system having basket-type electrodes; FIG. 10 is an explanatory view showing the main configuration of a conventional electrode catheter ablation system having bell-shaped electrodes; 1 is an explanatory diagram showing the configuration of a main part of a high-frequency hot balloon catheter system according to one embodiment of the present invention; FIG. FIG. 2 is a diagram showing the state of use of the high-frequency hot balloon catheter system used in the present invention; FIG. 4 is an explanatory diagram conceptually representing electrical signals transmitted from the left atrium (LA) to the pulmonary vein (PV) near the pulmonary vein ostium before ablation treatment. FIG. 10 is an explanatory diagram showing how the conduction of electrical signals generated in the left atrium (LA) is blocked at the ablation treatment portion after the ablation treatment. FIG. 2 is an electrocardiogram waveform in which the pulmonary vein potential (PVP) transmitted from the left atrium (LA) to the pulmonary vein (PV) is recorded, observed with the bipolar electrodes of the present invention before the ablation procedure. FIG. 4 is an X-ray fluoroscopic view during treatment using the high-frequency hot balloon catheter system according to the present invention; FIG. 10 is an explanatory diagram showing how, during pulmonary vein pacing, a pulse-wave electrical signal generated by an electrical stimulator electrically stimulates a myocardial sleeve in the pulmonary vein from a bipolar electrode, and the excitation wave is transmitted to the left atrium. ECG waveform when pulmonary vein pacing is performed before ablation. FIG. 4 is an explanatory diagram conceptually showing how conduction of excitation waves by electrical stimulation is blocked at an ablation treatment site. It is an electrocardiogram waveform when pulmonary vein pacing is actually performed while performing ablation. 4 is a graph showing the relationship between the intensity of stimulation electricity required to excite pulmonary veins and its pulse width.

Hereinafter, the high-frequency hot balloon catheter system proposed by the present invention will be described in detail with reference to the attached drawings. In the following description, unless otherwise specified, the terms “front” or “front side” refer to the distal side where the tip of the guide wire 10 described later is located, and “back” or “back side”. ” refers to the proximal side that is handled by the operator.

FIG. 3 shows the essential configuration of a balloon catheter ablation system in one embodiment of the present invention. In the figure, 1 is a tubular catheter shaft that is highly flexible and can be inserted into a hollow organ. This catheter shaft 1 is composed of an outer cylinder 2 and an inner cylinder 3 that are slidable in the longitudinal direction. be done. Between the distal end portion 4 of the outer tube 2 and the vicinity of the distal end portion 5 of the inner tube 3, a contractible and expandable balloon 6 is provided. The balloon 6 is formed into a thin film from a heat-resistant resin such as polyurethane or PET (polyethylene terephthalate), and the inside of the balloon 6 is filled with a liquid (usually a mixture of physiological saline and a contrast agent). As a result, it swells into a shape of a body of revolution, for example, a substantially spherical shape.

Between the outer cylinder 2 and the inner cylinder 3 inside the catheter shaft 1, there is a liquid feed passage 9 which leads to a filling portion 8 formed inside the balloon 6, and which feeds the liquid to the filling portion 8 and transmits vibration waves. It is formed. Reference numeral 10 denotes a guide wire for guiding the balloon portion 8 to the target site S, and this guide wire 10 is provided so as to pass through the inner cylinder 3 .

A high frequency electrode 11 and a temperature sensor 12 are installed inside the balloon 6, respectively. The high-frequency conducting electrode 11 serves as an electrode for heating the inside of the balloon 6 and is wound around the inner cylinder 3 in a coil shape. Further, the high-frequency conducting electrode 11 has a monopolar structure, and is configured to conduct high-frequency conduction between a counter electrode plate 13 provided outside the catheter shaft 1. When the high-frequency conducting electrode 11 heats up. It should be noted that the high-frequency conducting electrode 11 may be configured to have a bipolar structure so that high-frequency conducting is performed between the two poles.

A temperature sensor 12 as a temperature detection unit is provided inside the balloon 6 on the base end side of the inner cylinder 3, and is in contact with the high-frequency electrode 11 to detect the temperature of the high-frequency electrode 11. It has become. Although not shown in the present embodiment, in addition to the temperature sensor 12, another temperature sensor for detecting the internal temperature of the balloon 6 may be fixed near the distal end portion 5 of the inner cylinder 3.

Further, outside the balloon 6 , a pair of bipolar electrodes 16 a and 16 b are installed forward of the balloon 6 at the distal end portion 5 of the inner cylinder 3 . At this time, of the bipolar electrodes 16a and 16b, the bipolar electrode 16b, which is the proximal electrode on the rear side, is provided close to the membrane surface of the balloon 6 preferably at a distance of 0.5 to 2.0 mm, and the myocardial sleeve of the pulmonary vein ostium is approached. Further, of the bipolar electrodes 16a and 16b, the bipolar electrode 16a, which is the distal electrode on the front side, is provided at a predetermined position from the bipolar electrode 16b on the rear side toward the tip of the inner cylinder 3. , the front bipolar electrode 16a is placed at a distance of 2 to 5 mm, preferably 2.5 to 5.0 mm, from the rear bipolar electrode 16b. These bipolar electrodes 16a and 16b are electrically connected to an intracardiac electrocardiograph 41 and an electrical stimulator 42 through conducting wires 43 and 44, respectively.

Both of the bipolar electrodes 16a and 16b adjacent to the inner membrane of the balloon 6 are made of a good electrical conductor such as gold, silver, copper or platinum, and are formed in a ring shape so as to be attached to the outer circumference of the distal end portion 5 of the inner cylinder 3. be done. The ring width D1 of these bipolar electrodes 16a, 16b is 1.5-3 mm and the inner diameter D2 is 2-5 mm.

Bipolar electrodes 16a, 16b are configured to sense electrical signals transmitted from the left atrium to the pulmonary veins (PV), which are transmitted via current lines 43 as pulmonary vein potentials to the intracardiac electrocardiogram. 41 is configured to be recorded. At the same time, the electrical stimulator 42 is configured to allow a stimulating current to flow through the bipolar electrodes 16a and 16b via a conducting wire 44, and the balloon 6 is brought into close contact with the wall surface of the hollow organ, causing the current to flow through the hollow organ. It is configured such that a stimulating current can be applied to the left atrium from the bipolar electrodes 16a and 16b while blood flow is completely blocked. As will be described in detail later, the myocardial sleeve in the pulmonary vein is electrically stimulated (pulmonary vein pacing) by bipolar electrodes 16a and 16b provided at the tip of the balloon 6 during ablation, and the excitation wave is transmitted to the atrium to excite the atrium. The condition is observed by an intracardiac electrocardiograph 41, and the disappearance of this atrial capture can be used as an indicator of the achievement of pulmonary vein isolation. The intracardiac electrocardiograph 41 is configured to be electrically connectable to various intracardiac electrodes (not shown) such as an RA electrode and a CS electrode, and is capable of recording/monitoring the electrocardiographic potential accompanying capture of the atria and ventricles. It's becoming

A potential amplifying device and a high frequency filter (not shown) can be installed outside the balloon shaft 1 . The potential amplifying device can be incorporated as part of the extracorporeal electrocardiograph 41 or can be provided independently of the electrocardiograph 41 . The potential amplifying device can be connected to the bipolar electrodes 16a and 16b placed at the tip of the balloon 6 through a current-carrying wire 43, and functions as an amplifying device for amplifying and recording remote potentials obtained from the bipolar electrodes 16a and 16b. to monitor changes in these potential waveforms to track the progress of ablation of the target tissue. Further, a high frequency filter can be incorporated here in order to eliminate the influence of high frequency noise generated from a high frequency generator 31, which will be described later. The electric wires 43 and 44 can be fixed along the inner cylinder 3 over the entire axial length of the inner cylinder 3 .

A balloon catheter 21 having a shape that can be inserted into the body is configured by the catheter shaft 1 and the balloon 6 described above. Outside the balloon catheter 21 , a liquid-feeding pipe 22 is connected to the proximal end of the liquid-feeding path 9 . Two connecting ports of a three-way stopcock 23 are connected to the middle of the liquid feeding tube 22 , and the remaining one connecting port of the three-way stopcock 23 is connected to a syringe 24 for deflating and expanding the balloon 6 . A vibration generator 25 for internal agitation of the balloon 6 is connected to the proximal end of the liquid feeding pipe 22 . The three-way stopcock 23 is provided with an operation piece 27 that can be rotated with a finger. By operating this operation piece 27, either the syringe 24 or the vibration generator 25 is connected to the liquid feed path 9. It is configured to let

A syringe 24 as a liquid injection aspirator comprises a tubular body 28 connected to a three-way stopcock 23 and a movable plunger 29 . When the plunger 29 is pushed while the three-way stopcock 23 is in communication with the syringe 24 and the liquid feed path 9, the liquid is supplied from the inside of the cylindrical body 28 through the liquid feed path 9 to the inside of the balloon 6. Conversely, when the plunger 29 is pulled back, the liquid passes through the liquid feed path 9 from the inside of the balloon 6 and is recovered inside the cylindrical body 28 .

Vibration generator 25, which constitutes the in-balloon agitator together with liquid feed pipe 22, is in communication with liquid feed channel 9 via three-way stopcock 23, and applies asymmetric vibration waves to the liquid inside paloon 6 through liquid feed channel 9. , which generates vortices constantly. The vortex inside the paloon 6 vibrates and agitates the liquid inside the balloon 6 so that the inside temperature of the balloon 6 is kept uniform.

A high-frequency generator 31 is provided outside the balloon catheter 21, and the high-frequency conducting electrode 11 and the temperature sensor 12 provided inside the balloon 6 are connected to current-carrying wires 32 and 33 provided inside the catheter shaft 1, respectively. is electrically connected to the high-frequency generator 31 by. The high-frequency generator 31 supplies high-frequency energy, which is electric power, between the high-frequency electrode 11 and the counter electrode plate 13 through a current-carrying wire 32 to heat the entire balloon 6 filled with liquid. A thermometer (not shown) is provided for measuring and outputting the internal temperature of the electrode 11 for high-frequency current conduction and the balloon 6 according to the detection signal from the temperature sensor 12 sent through the conducting wire 33, and displaying the temperature. Further, the high-frequency generator 31 sequentially takes in temperature information measured by a thermometer, and is configured to determine the energy of the high-frequency current supplied between the high-frequency electrode 11 and the counter electrode plate 13 through the current-carrying line 32. . The electric wires 32 and 33 are fixed along the inner cylinder 3 over the entire axial length of the inner cylinder 3 .

The balloon catheter 21 including the catheter shaft 1 and the balloon 6 is entirely made of a heat-resistant resin material that can withstand heat deformation when the interior is heated. The shape of the balloon 6 may be a spherical shape with the short axis equal to the long axis, a flat sphere with the short axis as the rotation axis, an elongated sphere with the long axis as the rotation axis, or various shapes of revolution such as a bale shape. However, no matter what shape it is, it is formed of a highly compliant elastic member that deforms when in close contact with the inner wall of the lumen.

Next, the actual usage of the balloon catheter ablation system of the present invention will be described with reference to FIG. 4 showing the usage of the balloon catheter 21 of FIG.

The balloon catheter ablation system according to the present invention is used for the purpose of isolating the pulmonary vein (PV), which is the source of atrial fibrillation, in a patient with atrial fibrillation and eradicating the atrial fibrillation itself.

First, the femoral vein is punctured under anesthesia, the guide wire 10 is inserted, the guide sheath 51 is inserted into the left atrium (LA) through the guide wire 10, and the balloon catheter 21 is inserted through the guide sheath 51. , the bipolar electrodes 16a and 16b located at the tip of the balloon 6 are placed in the opening of the pulmonary vein. Next, the balloon 6 is expanded by injecting a mixed solution of contrast agent and physiological saline into the balloon 6 from a syringe 24 attached to the balloon catheter 21, and the membrane surface of the balloon 6 is pushed to the target site S of the pulmonary vein ostium. guess. FIG. 4 illustrates the inflated balloon 6 and bipolar electrodes 16a, 16b placed in the pulmonary vein opening.

FIG. 5A is an explanatory diagram conceptually showing electrical signals transmitted from the left atrium (LA) to the pulmonary vein (PV) near the ostia of the pulmonary vein before ablation treatment. When the bipolar electrodes 16a, 16b are placed in close proximity to the myocardial sleeve at the pulmonary vein ostium, the pulmonary venous potential (PVP) of the pulmonary vein (PV) is applied via current lines 43 connected to the bipolar electrodes 16a, 16b. , is recorded by the intracardiac electrocardiograph 41 . In the figure, the PV on the left represents the pulmonary veins and the LA on the right represents the side of the left atrium. In the figure, the triangular waveforms shown above the tip electrodes 16a and 16b conceptually represent electrical signals transmitted from the left atrium (LA) to the pulmonary veins (PV). The two bold arrow symbols seen above and below the pulmonary vein portion indicate the direction in which this electrical signal propagates. Bipolar electrodes 16a, 16b are configured to sense electrical signals transmitted from the left atrium to the pulmonary veins (PV), which are transmitted via current lines 43 as pulmonary venous potentials (PVP) to the intracardiac heart. It is recorded in the electric meter 41 .

FIG. 5B shows that after the ablation treatment, the conduction of the electrical signal generated in the left atrium (LA) is blocked at the ablation treatment part, so that the electrical signal is not transmitted from the left atrium (LA) to the pulmonary vein (PV). It is an explanatory view showing the. In the drawing, the darkly hatched portion at the pulmonary vein ostium in contact with the balloon 6 indicates the target site S' where the ablation treatment was performed. It was confirmed by the intracardiac electrocardiograph 41 that the electrical signal from the left atrium was blocked at the target site S' after this ablation procedure and that such pulmonary venous potential (PVP) was no longer sensed by the bipolar electrodes 16a and 16b. By doing so, it is possible to determine whether the ablation was successful.

FIG. 6 shows the pulmonary venous potential (PVP) transmitted from the left atrium (LA) to the pulmonary vein (PV) observed by the intracardiac electrocardiograph 41 via the bipolar electrodes 16a and 16b of the present invention before the ablation procedure. is an electrocardiogram waveform in which is recorded. In the figure, the waveform labeled Hot 1-2 on the left side represents pulmonary vein potential recording at the bipolar electrodes 16a and 16b provided at the tip of the balloon catheter 21. FIG. A total of 10 lines labeled RA represent electrocardiographic waveforms of intracardiac potentials sensed by RA electrodes placed in the right atrium (RA). In the figure, a small wave P1 seen ahead of three thick arrow symbols T1 indicates a pulmonary vein potential associated with an electrical signal transmitted from the left atrium (LA) to the pulmonary vein (PV). However, such a pulmonary vein potential waveform P1 is extremely small and cannot be used to determine whether the ablation was successful.

Therefore, in the present invention, pulse wave electrical signals are sent from the electrical stimulator 42 to the bipolar electrodes 16a and 16b to electrically stimulate the myocardial sleeve in the pulmonary veins from the bipolar electrodes 16a and 16 to perform pulmonary vein pacing. An intracardiac electrocardiograph 41 observes how the wave propagates to the atrium and excites the atrium, and the disappearance of this atrial capture can be used as an indicator of the achievement of pulmonary vein isolation.

For this purpose, a contrast agent is first injected from the tip of the balloon 6 . FIG. 7 is an X-ray fluoroscopic view of the balloon catheter 21 during left lower pulmonary vein isolation using the high frequency hot balloon catheter system according to the present invention. When an X-ray contrast image showing obstructive PV is obtained, since the balloon 6 is in close contact with the ostium of the pulmonary vein, the high-frequency power supply by the high-frequency generator 31 is started while measuring the core temperature inside the balloon 6 with a thermometer. do. After the central temperature in the balloon 6 reaches 70° C., the current is continued for 2 to 3 minutes. At this time, if the pulmonary vein potential (PVP) measured by the intracardiac electrocardiograph 41 disappears within 30 seconds, it indicates that the pulmonary vein isolation by ablation is progressing smoothly.

After that, when the pulmonary vein potential (PVP) disappears, the following pulmonary vein pacing is performed to confirm whether or not atrial capture occurs. In pulmonary vein pacing, even when the recording of the pulmonary vein potential (PVP) described above is not successful, high-frequency energization is performed by the high-frequency generator 31 while confirming atrial capture by pacing, thereby determining whether the ablation treatment was successful. can be confirmed.

FIG. 8 shows that during pulmonary vein pacing before the ablation procedure is completed, the pulse wave electrical signal generated by the electrical stimulator 42 electrically stimulates the myocardial sleeve in the pulmonary vein from the bipolar electrodes 16a and 16b, and the excitation wave FIG. 2 is an explanatory diagram conceptually showing how the is transmitted to the left atrium. In the figure, the pulse waveform waveform shown above the bipolar electrodes 16a, 16b is the electrical stimulation pulse delivered from the bipolar electrodes 16a, 16b to the pulmonary vein myocardial sleeve to electrically stimulate the pulmonary vein myocardial sleeve. represents a wave signal. In the figure, the two thick arrow symbols seen in the pulmonary vein portion above and below the balloon 6 indicate the direction in which the excitation wave of the myocardial sleeve in the pulmonary vein electrically stimulated by pacing propagates to the atria. In this way, the atrium captures the excitation wave of the intrapulmonary vein myocardial sleeve as it is propagated to the atrium by pulmonary vein pacing.

FIG. 9 shows an electrocardiogram waveform when pulmonary vein pacing is actually performed before the ablation procedure is completed using the high-frequency hot balloon catheter system according to the present invention. In the figure, the four thick arrow symbols T2 represent the positions where electrical stimulation was performed from the bipolar electrodes 16a and 16b by the electrical stimulator 42, and the circle symbol R2 written below the RA electrode line represents the bipolar electrode Pacing by 16a, 16b represents the location of waveform P2 in which the atrium was captured. From this intracardiac electrocardiogram waveform, before the ablation procedure is completed, when electrical stimulation is applied to the myocardial sleeve near the pulmonary vein ostium from the bipolar electrodes 16a and 16b, a pair of atrial capture waveforms P2 is generated for the pacing electrical stimulation. It can be seen that they occur synchronously at a rate of 1.

FIG. 10 shows that during pulmonary vein pacing after ablation, the electrical stimulation pulse wave signal generated by the electrical stimulator 42 electrically stimulates the myocardial sleeve in the pulmonary vein from the bipolar electrodes 16a and 16b, but the excitation wave conduction is blocked at the target site S' after the ablation treatment indicated by hatching. In the figure, the pulse wave-shaped waveform shown above the bipolar electrodes 16a, 16b is an electrical pulse delivered from the bipolar electrodes 16a, 16b to the pulmonary vein myocardial sleeve to electrically stimulate the pulmonary vein myocardial sleeve. 3 represents a stimulation pulse wave signal. The electrical stimulation pulse wave here has a stimulation time width (pulse width) of 5 to 10 ms and a stimulation voltage of 10 to 20V. In the figure, the two thick arrow symbols seen in the pulmonary vein portion on the upper and lower left sides of the balloon indicate the direction in which the excitation wave of the myocardial sleeve in the pulmonary vein electrically stimulated by pacing propagates. Thus, although pulmonary venous pacing produces an excitation wave in the pulmonary vein myocardial sleeve, it is blocked by the ablation and therefore not conducted to the atria. Therefore, if the ablation procedure is successful, as will be described in detail below, the atrial capture associated with pulmonary venous pacing disappears, and the pulmonary venous pacing and the atrial rhythm are not synchronized and divergence is observed. Successful ablation can be determined by the disappearance of .

FIG. 11 shows an electrocardiogram waveform when pulmonary vein pacing is actually performed while performing ablation using the high-frequency hot balloon catheter system according to the present invention. As in FIG. 9, four thick arrow symbols T2 represent positions where electrical stimulation was performed from the bipolar electrodes 16a and 16b by the electrical stimulator 42. FIG. From this electrocardiogram waveform, it can be read that as the ablation progresses and the pulmonary vein isolation progresses, the electrical stimulation and the atrial wave diverge without synchronism. If pulmonary venous pacing and atrial rhythm deviate from each other in this way, conduction from the pulmonary vein (PV) to the atrium is blocked, and it can be determined that pulmonary vein isolation by ablation is successful. On the other hand, if no pulmonary vein potential disappearance or atrial-pulmonary vein dissociation is observed even after 30 seconds or more after the balloon temperature reaches 70 degrees Celsius, the ablation is unsuccessful, and the high-frequency current from the high-frequency generator 31 is restarted. It is necessary to stop and change the position of the balloon 6.

Thus, even when pulmonary vein potential (PVP) recording is unsuccessful, it is possible to perform high-frequency energization by the high-frequency generator 31 while observing the atrium capture by the pulmonary vein pacing with the intracardiac electrocardiograph 41. . Also, loss of pulmonary vein potential and loss of atrial capture with pulmonary venous pacing are indicative of bidirectional block between the pulmonary veins and the left atrium.

FIG. 12 shows the relationship between the intensity of the stimulating electricity from the electrical stimulator 42 and its pulse width required to excite the pulmonary veins using the high-frequency hot balloon catheter system according to the present invention. It is a graph showing the current intensity [unit; mA] and the horizontal axis as the pulse width [unit; ms] of the stimulation current. In the figure, the dashed line marked with the symbol A represents the graph when the bipolar electrodes 16a and 16b are close to the inner wall of the pulmonary vein, and the dashed line marked with the symbol B is shown by the dashed line with the symbol A. The graph represents the case where the bipolar electrodes 16a, 16b are far from the inner wall of the pulmonary vein.

The electrical stimulator 42 outputs stimulation current pulses to the bipolar electrodes 16a and 16b with an output intensity of 5 to 100 mA (milliamperes) and a pulse width of each stimulation current pulse of 5 to 30 ms (milliseconds). It is preferable to incorporate an electric circuit that can be set by operating an operation body (not shown) so that continuous pacing can be performed periodically at a rate of 60 to 150 stimulation current pulses per minute. . As shown in the graph of FIG. 12, regardless of the distance between the bipolar electrodes 16a and 16b and the inner wall of the pulmonary vein, the wider the pulse width of the stimulation current pulse, the smaller the current intensity that electrically excites the pulmonary vein. is allowed. It will also be appreciated that the farther the bipolar electrodes 16a, 16b are from the inner wall of the pulmonary vein, the higher the current intensity required.

Thus, in this embodiment, the bipolar electrodes 16a and 16b are installed at the distal end of the balloon catheter 21 in close proximity to the membrane surface of the balloon 6, and the stimulating current with a wide pulse width and high intensity is applied from the electrical stimulator 42 to the bipolar electrodes 16a and 16b. By supplying the pulse, pulmonary vein pacing becomes possible in the vicinity of the myocardial sleeve near the pulmonary vein ostium. can be monitored.

As described above, in the high-frequency hot balloon catheter system of this embodiment, the elastic balloon 6 is installed between the outer tube 2 and the inner tube 3 that are slidable with each other, and the balloon 6 is placed at the tip of the inner tube 3. Bipolar electrodes 16a and 16b, which serve as tip electrodes, are placed in close proximity to the membrane surface of the heart. 41 and an electric stimulator 42, and a high-frequency electrode 11 and a temperature sensor 12 are installed in the balloon 6, and these high-frequency electrode 11 and temperature sensor 12 serve as a second current-carrying wire. A high-frequency generator 31 and a thermometer are connected to an extracorporeal high-frequency generator 31 and a thermometer by electric wires 32 and 33, and a liquid feeding path 9 leading to the balloon 6 is formed between the outer cylinder 2 and the inner cylinder 3. One of them is connected to the inside of the balloon 6, and the other of the liquid feeding path 9 is connected to a syringe 24 for injecting and sucking the liquid into the balloon 6 and an extracorporeal vibration generator 25. FIG.

In this case, bipolar electrodes 16a and 16b are installed near the membrane surface of the balloon 6 at the distal end of the inner cylinder 3, and these bipolar electrodes 16a and 16b are connected to an intracardiac electrocardiograph 41 via a current-carrying wire 43. . By providing a bipolar electrode at the tip of the balloon 6, the pulmonary vein potential is recorded on the intracardiac electrocardiograph 41 via blood with relatively good conductivity, and the progress of pulmonary vein isolation by ablation is confirmed. can be done. Furthermore, since the bipolar electrodes 16a and 16b are also connected to the electric stimulator 42 via the current line 44, even if the disappearance of the pulmonary vein potential due to the pulmonary vein isolation is unclear, the pulmonary stimulation using the electric stimulator 42 can be performed. The progress of pulmonary vein isolation can be monitored with high accuracy by confirming the presence or absence of atrium capture associated with venous pacing with the intracardiac electrocardiograph 41 .

In the high-frequency hot balloon catheter system described above, the bipolar electrodes 16a and 16b are close to the membrane surface of the balloon 6, and are each made of a good electrical conductor such as gold, silver, copper, or platinum and have a ring shape. .5-3 millimeters and the inner diameter D2 is configured to be 2-5 millimeters.

In this case, the bipolar electrodes 16a and 16b adjacent to the membrane surface of the balloon 6 are made of a good electrical conductor such as gold, silver, copper or platinum and are ring-shaped. D2 is 2-5 millimeters. Therefore, the electrical potential of the myocardial tissue can be sensed with high sensitivity, and it can be adapted to the use of electrical stimulation with a wide pulse width and high intensity.

In the high-frequency hot balloon catheter system described above, the bipolar electrodes 16a and 16b are composed of a proximal electrode and a distal electrode. The distal bipolar electrode 16a, which is placed in close proximity with a distance of 0.0 millimeters, is placed 2 to 5 millimeters distal to the bipolar electrode 16b, which serves as the proximal electrode.

In this case, the bipolar electrodes 16a and 16b are composed of a proximal electrode and a distal electrode, and the bipolar electrode 16b serving as the proximal electrode is close to the membrane surface of the balloon 6 at a distance of 0.5 to 2.0 mm. installed in position. Therefore, the pulmonary vein potential can be monitored and the pulmonary vein pacing can be performed by bringing the device close to the pulmonary vein ostium where the myocardial sleeve is developed. Further, the bipolar electrode 16a, which is the distal electrode, is placed 2 to 5 mm distal to the bipolar electrode 16b, which is the proximal electrode. Pulmonary venous pacing can be performed successfully without touching the venous wall.

In the high-frequency hot balloon catheter system described above, the output intensity of the electric stimulator 42 is 5 to 100 milliamperes, the pulse width is 5 to 30 milliseconds, and continuous pacing is possible at a rate of 60 to 150 per minute. It is.

In this case, the output intensity of the electrical stimulator is 5 to 100 milliamperes (mA), the output pulse width is 5 to 30 milliseconds (ms), and continuous pacing is performed at a rate of 60 to 150 per minute to control the balloon tip. Pulmonary venous pacing can be performed appropriately even if the bipolar electrode is not in contact with the pulmonary vein wall and is separated from the wall of the pulmonary vein. , 16b.

The present invention is not limited to this embodiment, and various modifications can be made within the scope of the present invention. INDUSTRIAL APPLICABILITY The present invention can be applied to dilation of narrowed portions of hollow organs such as urethra, ureter, pancreatic duct, trachea, esophagus, and intestinal tract, in addition to blood vessels and bile ducts. Further, the shapes of the electrodes 16a, 16b, the catheter shaft 1, the balloon 6, the guide wire 10, etc. are not limited to those shown in the above embodiment, and may be formed in various shapes according to the treatment site.

2 Outer cylinder 3 Inner cylinder 6 Balloon 9 Liquid feeding path 11 Electrode for high frequency current 12 Temperature sensor 16a Bipolar electrode (distal electrode)
16b bipolar electrode (proximal electrode)
24 Syringe 25 Extracorporeal Vibration Generator 32, 33 Power Line (Second Power Line)
41 Intracardiac electrocardiograph 42 Electrical stimulator 43, 44 Conducting wire (first conducting wire)

Claims (4)

An elastic balloon is installed between the outer cylinder and the inner cylinder that are slidable to each other,
A bipolar electrode is installed at the tip of the inner cylinder in proximity to the balloon membrane surface,
The bipolar electrodes are connected to an extracorporeal intracardiac electrocardiograph and an electrical stimulator via a first conducting line,
A high-frequency electrode and a temperature sensor are installed in the balloon,
The high-frequency electrode is connected to an extracorporeal high-frequency generator and the temperature sensor is connected to a thermometer by a second conductive line ,
Between the outer cylinder and the inner cylinder, a liquid feeding path leading to the inside of the balloon is formed,
1. A high-frequency hot balloon catheter system, wherein one of said liquid feeding channels is connected to said balloon, and the other is connected to a syringe for injecting and sucking liquid into said balloon and an extracorporeal vibration generator. The bipolar electrode is close to the balloon membrane, is made of a good electrical conductor such as gold, silver, copper or platinum, and is ring-shaped, with a ring width of 1.5-3 mm and an inner diameter of 2-5 mm. The high frequency hot balloon catheter system of claim 1, wherein the high frequency hot balloon catheter system is characterized by: The bipolar electrode is composed of a proximal electrode and a distal electrode, the proximal electrode is placed in proximity to the balloon membrane surface at a distance of 0.5 to 2.0 millimeters, and the distal electrode is the proximal electrode. 3. The high-frequency hot balloon catheter system according to claim 1, wherein the distance between the electrodes is 2 to 5 mm distal to the position electrode. The electrical stimulator has an output of 5 to 100 milliamperes, a pulse width of 5 to 30 milliseconds, and is configured to enable continuous pacing at a rate of 60 to 150 per minute. The high frequency hot balloon catheter system according to any one of claims 1 to 3.

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