Radiofrequency electrode ablation catheter with cooling function for ventricular septal therapy

Abstract

The present invention relates to a radiofrequency electrode ablation catheter for ventricular septal therapy with a cooling function, which is used for performing radiofrequency electrode ablation and has a cooling function for preventing carbonization of body (ventricular septum) tissue around the electrode, wherein radiofrequency energy is applied to the ventricular septum during radiofrequency electrode ablation to perform ventricular septal therapy (e.g., therapy for hypertrophic cardiomyopathy, a disease in which the left ventricular septum of the heart of an animal or human body becomes thickened, therapy requiring reduction of the ventricular septum, or ventricular tachycardia, etc.). The radiofrequency catheter for ventricular septal therapy according to a preferred embodiment of the present invention includes a septal insertion portion and a body portion.

Description

Technical Field

[0001] The present invention relates to a radiofrequency electrode ablation catheter for septal therapy with a cooling function, which relates to a radiofrequency electrode ablation catheter for septal therapy used for performing radiofrequency electrode ablation, wherein radiofrequency energy is applied to the ventricular septum during the radiofrequency electrode ablation to perform septal reduction theraphy (for example, treatment of hypertrophic cardiomyopathy, a disease in which the left ventricular septum of the heart of an animal or human being becomes thickened, treatment requiring reduction of the septum, or septal reduction theraphy such as ventricular tachycardia).

[0002] Furthermore, the present invention relates to a radiofrequency electrode ablation catheter for ventricular septal therapy having a cooling function for preventing carbonization of body (ventricular septal) tissue surrounding the electrode. Background Art

[0003] Septal reduction therapies include treatments for hypertrophic cardiomyopathy, treatments that require reduction of the ventricular septum, and ventricular tachycardia.

[0004] Hypertrophic cardiomyopathy, a typical type of ventricular septal therapy, refers to a heart disease that causes thickening of the left ventricular wall without other symptoms, such as aortic stenosis or hypertension, which may cause left ventricular hypertrophy. It occurs in 1 in 500 people, and various types of left ventricular hypertrophy are observed. The most common representative features are asymmetrical septal hypertrophy and unstable left ventricular outflow tract obstruction (closed and blocked).

[0005] Figure 1 The diagram shows the symptoms of hypertrophic cardiomyopathy and the surgical methods commonly performed currently.

[0006] Reference Figure 1 The general method of surgery for hypertrophic cardiomyopathy is to insert a knife into the left ventricle through the aortic valve and then cut out the enlarged left ventricular septum as shown in the figure. That is, a method of cutting out the enlarged ventricular septum using a knife and the feel of an expert is used.

[0007] In addition, as another method, a method using radiofrequency energy has recently been published. Treatment of septal hypertrophy by radiofrequency electrode ablation (RF ablation) has been frequently published since the past, but they are all methods of positioning a catheter in the left ventricle and performing radiofrequency electrode ablation (RF ablation) on the surface of the left ventricle.

[0008] Recently, a method of using a needle to penetrate the inside of the septum for treatment, rather than treating on the surface of the septal hypertrophy, has been reported to show unexpectedly excellent results. That is, results have recently been published that have shown very good treatment effects when radiofrequency electrode ablation is performed close to the intra-septum.

[0009] (Percutaneous Intramyocardial Septal Radiofrequency Ablation for Hypertrophic Obstructive Cardiomyopathy. Journal of the American College of Cardiology Volume 72, Issue 16, October 2018)

[0010] However, in the above-mentioned paper, since a hard needle is used to approach the intraseptum, there is a disadvantage that the treatment method is very dangerous.

[0011] Prior art literature

[0012] Patent Literature

[0013] (Patent Document 0001) Korean Registered Patent Publication No. di210-1626958 (Registered on May 27, 2016) (High-frequency catheter with multiple electrodes)

[0014] Non-patent literature

[0015] (Non-patent document 0001) Percutaneous intramyocardial septal radiofrequency ablation for hypertrophic obstructive cardiomyopathy. Journal of the American College of Cardiology Volume 72 (16, October 2018.) Summary of the invention

[0016] Technical issues to be solved

[0017] The object of the present invention is to provide a radiofrequency electrode ablation catheter for ventricular septal therapy, that is, the radiofrequency electrode ablation catheter for ventricular septal therapy injects physiological saline (cooling liquid) for cooling from the proximal end of the catheter to reduce the temperature of the electrode at the distal end to prevent carbonization around the electrode, thereby facilitating high-frequency transmission and making the ablation range wider.

[0018] Another object of the present invention is to provide a radio frequency electrode ablation catheter for ventricular septal therapy, that is, the radio frequency electrode ablation catheter for ventricular septal therapy can reduce the outer diameter of the radio frequency catheter, can easily pass through the narrow blood vessels of the heart, and minimize the possibility of contact with high-frequency power lines and temperature sensing lines, etc., thereby reducing insulation problems that may occur in the catheter, making the length of the tube for transmitting cooling liquid short, and thus being able to inject cooling liquid with a lower pressure pump.

[0019] The objects of the present invention are not limited to the above-mentioned objects, and a person skilled in the art of the present invention can clearly understand other objects not mentioned through the following description.

[0020] Solutions to technical problems

[0021] In order to achieve the above-mentioned purpose of the present invention, a radiofrequency catheter for ventricular septal therapy according to a preferred embodiment of the present invention includes a septal insertion portion and a main body portion, wherein the septal insertion portion is formed with a tip at the distal end of the distal portion, which is tapered and becomes thinner as it moves toward the distal end so as to penetrate and be inserted into the ventricular septum, and one or more electrodes are formed on the outer peripheral surface at a position adjacent to the tip, and the main body portion is made of a soft and flexible material and has a guide wire lumen that passes through the interior of the septal insertion portion from the center of the tip end so that a guide wire can be inserted, a cooling liquid introduction lumen that is connected to the interior of the septal insertion portion from the proximal end and has an open distal end so that cooling liquid can be injected from the outside, and a cooling liquid discharge lumen that is connected to the cooling liquid introduction lumen and has a discharge port formed on the side.

[0022] The spacer insertion portion penetrates and is inserted into the myocardium following the guidance of the guide wire, and the guide wire lumen and the cooling liquid introduction lumen are not communicated with each other but are separated from each other.

[0023] According to a preferred embodiment of the present invention, the cooling liquid that flows from the proximal end into the interior of the septal insertion portion through the cooling liquid introduction lumen is discharged into the cooling liquid discharge lumen and then discharged into the coronary sinus or vein through a discharge port formed on the side of the main body.

[0024] According to a preferred embodiment of the present invention, the cooling liquid discharge lumen has a structure surrounding the cooling liquid introduction lumen, and the cooling liquid injected along the cooling liquid introduction lumen flows in opposite directions along the cooling liquid discharge lumen surrounding the cooling liquid introduction lumen and is discharged into the coronary sinus or vein through a discharge port connected to the cooling liquid discharge lumen.

[0025] According to a preferred embodiment of the present invention, the cooling liquid discharge lumen has a structure surrounding the guide wire lumen, and the guide wire lumen passes through the cooling liquid discharge lumen.

[0026] According to another preferred embodiment of the present invention, the guide wire lumen does not pass through the interior of the cooling liquid discharge lumen but is positioned adjacent thereto.

[0027] According to a preferred embodiment of the present invention, the electrode performs the functions of connecting to a radio frequency generator to receive radio frequency energy and radiating radio frequency energy, and performs the functions of sensing electrical signals of the myocardium or applying electrical stimulation.

[0028] According to a preferred embodiment of the present invention, the guide wire lumen and the guide wire passing through the inside are in close contact with each other and have no space therebetween.

[0029] According to a preferred embodiment of the present invention, the spacer inserting portion has a spiral coil wire or a braided wire formed therein, and the wire is insulated from the electrode.

[0030] According to a preferred embodiment of the present invention, the spacer inserting portion is formed with a hydrophilic polymer coating at a surface portion other than a surface of the electrode.

[0031] According to a preferred embodiment of the present invention, the tapered tip has a length of 5 to 20 mm, an end portion has a thickness of 1.2 to 1.4 Fr, and a side opposite to the end portion has a thickness of 3 to 6 Fr.

[0032] According to a preferred embodiment of the present invention, the electrode wire transmitting radio frequency energy to the electrode is coated and wound on the surface of the catheter in the radial direction (spiral wrapped), and is connected with electrode wires corresponding to the number of the electrodes. Preferably, the electrode wire is a silver wire.

[0033] According to a preferred embodiment of the present invention, from the proximal end to the electrode, two thermocouple wires are wound on the surface of the catheter in a radial direction in a state of being wound around each other to measure the temperature of the electrode, and more preferably, one of the thermocouple wires is a nickel-chromium wire that is harmless to the human body, and the other is a nickel-aluminum alloy wire that is harmless to the human body.

[0034] Effects of the Invention

[0035] According to the present invention, there are the following effects.

[0036] 1. Radiofrequency electrode ablation is performed using a soft radiofrequency electrode ablation catheter instead of a hard needle, so it can smoothly enter along the curved septal vein and perform the treatment safely.

[0037] 2. Passing the radiofrequency electrode ablation catheter through the coronary sinus and septal vein can block complications of treatment methods such as approaching the left ventricular endocarium through the coronary artery, aortic valve or mitral valve, or approaching by direct needle puncture.

[0038] 3. Preferably, cooling is performed during the radiofrequency electrode ablation, and the risk of charring (black spots) or tissue defects in the endocarium can be reduced by cooling.

[0039] 4. When transmitting radiofrequency energy into the ventricular septum, (1) good contact with surrounding tissues is achieved, (2) a homogeneous lesion can be created, which is an advantage of radiofrequency energy, and (3) the degree of radiofrequency can be titrated to control the degree of tissue damage in stages, thereby enabling sufficient therapeutic effects to be expected through a small diameter (approximately 2 to 6 Fr) structure that can penetrate into the ventricle.

[0040] 5. It can simultaneously avoid tissue damage to the left ventricular endocardium, thereby preventing complete atrioventricular block, and because tissue damage is produced evenly, arrhythmia can be minimized.

[0041] 6. The electrodes formed at the surface of the radio frequency electrode ablation catheter perform not only the role of applying radio frequency energy but also the role of sensing or electrical stimulation.

[0042] Before performing radiofrequency electrode ablation, after directly sensing the electrical signals of the myocardium through the electrodes or applying the electrical signals through the electrodes, the electrocardiogram of the heart rate generated thereby can be used to pre-judge whether the electrodes are positioned close to the His bundle of the myocardium, thereby improving the stability of the radiofrequency electrode ablation and thus the reliability of the treatment method of the present invention.

[0043] 7. The cooling liquid discharge lumen has a structure surrounding the cooling liquid introduction lumen, thereby reducing the outer diameter of the radiofrequency electrode ablation catheter. In the case of a radiofrequency electrode ablation catheter for ventricular septal therapy that passes through narrow blood vessels of the heart and targets the ventricular septum, the reduction in the outer diameter of the catheter is even more important.

[0044] 8. The coolant discharge lumen has a structure surrounding the coolant introduction lumen, thereby reducing the outer diameter of the catheter, thereby minimizing the possibility of contact with high-frequency power lines and temperature sensing lines, etc., thereby reducing insulation problems that may occur in the catheter, and the length of the tube for transmitting saline solution (coolant) becomes shorter, so that saline solution can be injected with a lower pressure pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 The symptoms and surgical methods of hypertrophic cariomypathy are shown.

[0046] Figure 2 Schematic diagram showing the radiofrequency electrode ablation catheter for ventricular septal therapy and the treatment method using the same according to the present invention.

[0047] Figure 3 It is an overall stereoscopic view, a partial enlarged view and a partial cross-sectional view of a radiofrequency electrode ablation catheter for ventricular septum therapy according to an embodiment of the present invention.

[0048] Figure 4 It is a cross-sectional view and a partially enlarged view of a radiofrequency electrode ablation catheter for ventricular septal therapy according to an embodiment of the present invention.

[0049] Figure 5 The shape of the electrode wire formed on the surface of the radio frequency electrode ablation catheter and the catheter for ventricular septal therapy according to an embodiment of the present invention are shown.

[0050] Figure 6 The shape of an electrode wire formed on the surface of a radio frequency electrode ablation catheter and a catheter for ventricular septal therapy according to another embodiment of the present invention are shown.

[0051] Description of Reference Numerals

[0052] 10: Guide wire

[0053] 100: RF ablation catheter

[0054] 110: Guidewire lumen

[0055] 112: Entrance

[0056] 114: Exit

[0057] 120: intra-septal part

[0058] 122: tapered tip

[0059] 124: Electrode

[0060] 130: body part

[0061] 140: Coolant introduction lumen (inlet lumen)

[0062] 150: Coolant outlet lumen

[0063] 152: Exit

[0064] 160: handle

[0065] 162: Coolant insertion port

[0066] 164: Power cord. DETAILED DESCRIPTION

[0067] The advantages and features of the present invention and methods for achieving them will become clear with reference to the embodiments described in detail below in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in a variety of different forms. This embodiment is only provided to make the disclosure of the present invention complete and to fully convey the scope of the invention to ordinary technicians in the technical field to which the present invention belongs, and the present invention is limited by the scope of the claims.

[0068] The main purpose of the present invention is to provide a soft catheter-type radiofrequency electrode ablation catheter that is not a hard needle, and to use it to obtain the therapeutic effect of intramyocardial or intraseptal ventricular septal therapy. In other words, a method of using a soft catheter that is not a hard needle to enter tissue is proposed.

[0069] Figure 2 Schematic diagram showing the radiofrequency electrode ablation catheter for ventricular septal therapy and the treatment method using the same according to the present invention.

[0070] Reference Figure 2 In the present invention, after positioning the guidewire at the hypertrophic ventricular septum through the coronary sinus and the septal vein, the radiofrequency electrode ablation catheter is transmitted to the treatment target site (i.e., the hypertrophic ventricular septum) along the pre-positioned guidewire. Subsequently, while continuously injecting a coolant from the outside, a radiofrequency generator is used to apply radiofrequency energy to the electrode formed at the end of the radiofrequency electrode ablation catheter, thereby performing radiofrequency electrode ablation.

[0071] Preferably, before performing radiofrequency electrode ablation, the electrodes are used to sense myocardial electrical signals or to confirm an electrocardiogram of the heart rate generated after electrical stimulation is applied, thereby determining whether the electrodes are close to (positioned close to) the His bundle of the myocardium.

[0072] First, a method of positioning the guide wire 10 (guidewire) in the treatment target site (hypertrophied ventricular septum) will be described.

[0073] A very thin guidewire (approximately 0.014") is passed through the coronary sinus and septal vein and positioned within the hypertrophied septum as the target site.

[0074] In the present invention, in order to approach the ventricular septum as the treatment target of the ventricular septal therapy through the septal vein, the coronary sinus having an opening in the right atrium is used. The neck vein or the femoral vein is used to approach the coronary sinus, and the superior vena cava or the inferior vena cava is approached using a guiding catheter.

[0075] The guide catheter is a guide catheter formed at the distal end with a balloon and / or a double lumen microcatheter. The guide catheter is a catheter that guides a guide wire to a desired position.

[0076] When approaching the coronary sinus, a guiding catheter is positioned to the distal part of the coronary sinus, and pressurized venogram is performed through the guiding catheter. To perform pressurized venogram, a balloon tipped guiding catheter is ideal.

[0077] When the septal vein is imaged by pressurized venography, a PTCA guidewire of about 0.014" is inserted into the septal vein closest to the target site. The PTCA guidewire enables more precise treatment by using real-time imaging equipment such as echocardiogram to provide imaging guidance that tells whether the wire has found the target site. In order to more precisely guide the directionality of the PTCA guidewire, a dual lumen microcatheter can be used to precisely guide the wire to the target site.

[0078] That is, in order to position the guide wire at the interventricular septum through the septal vein, (1) a pressurized venogram with a balloon guiding catheter formed at the distal end and / or (2) a dual lumen microcatheter or the like may be used.

[0079] In order to observe the septal vein more clearly, a pressurized venogram is used. For this purpose, a balloon tipped guiding catheter can be used as an auxiliary means.

[0080] In addition, in order to position the guidewire in the desired direction in the ventricular septum, a dual lumen microcatheter or the like can be used as an auxiliary means. The dual lumen microcatheter is a catheter formed with two lumens for inserting the guidewire. After positioning the first guidewire at the septal vein through the first lumen of the dual lumen microcatheter, the second guidewire is inserted through the second lumen of the dual lumen microcatheter. The second guidewire can move in a direction different from the first guidewire. As described above, the dual lumen microcatheter is a very useful therapy auxiliary catheter when the guidewire finds the target location in the ventricular septum.

[0081] In the septal vein located in the ventricular septal tissue that is not on the surface of the ventricular septum, the guidewire can be freely moved without problems such as bleeding. Since the septal vein exists in the ventricular septum, the guidewire is positioned in the hypertrophic myocardial septum using the septal vein. When using the septal vein, the guidewire can also be detached from the septal vein and moved to a desired location as needed. In this case, the aforementioned double-lumen catheter can be used.

[0082] Although similar access can be achieved theoretically using the coronary artery (septal artery), there are many cases where it is difficult to reach a target having various anatomical positions. In such cases, when the guide wire passes through the septal artery (septal artery), serious problems such as intramyocardial hemorrhage may occur. In addition, when the treatment method is performed through the coronary artery, thrombus or dissection in the coronary artery often occurs, which may be fatal. Therefore, as in the present invention, the guide wire is inserted using the septal vein (septal vein).

[0083] The approach method through the septal vein in the present invention can prevent the complications of treatment methods caused by existing approaches such as approaching the left ventricular endocarium through the coronary artery, aortic valve or mitral valve or approaching by direct needle puncture.

[0084] In addition, alcohol has been traditionally injected into the septal artery for treatment, but this is also difficult to control, so alcohol is transferred to undesired sites, which may cause unnecessary myocardial infarction and other problems, and also frequently causes conduction system disorders.

[0085] Subsequently, a radiofrequency electrode ablation catheter is positioned to a target site (within the hypertrophic ventricular septum) along a guidewire positioned at the hypertrophic ventricular septum. That is, after one or more guidewires are positioned at the target site, a radiofrequency electrode ablation catheter is inserted along the guidewires, thereby positioning the electrode to reach the target site.

[0086] With the electrode of the RF electrode ablation catheter positioned at the target site (within the hypertrophied ventricular septum), a RF generator is used to apply RF energy to the electrode (RF electrode) formed at the end of the RF electrode ablation catheter while coolant (saline) is injected from the outside through the coolant discharge lumen in the RF electrode ablation catheter, thereby performing RF electrode ablation.

[0087] Preferably, before performing radiofrequency electrode ablation, a step is performed to determine whether the electrode is positioned near the bundle of His of the myocardium. Whether the electrode is positioned near the bundle of His of the myocardium can be achieved by directly sensing the electrical signal of the myocardium or by confirming the electrocardiogram of the heart rate generated during electrical stimulation.

[0088] Reference Figure 2 The radio frequency electrode ablation catheter of the present invention passes through the superior vena cava (SVC) or the inferior vena cava (IVC) and the right atrium (RA), and then passes through the coronary sinus (CS) and penetrates and is inserted into the ventricular septum. In this state, radio frequency energy is supplied to the electrode, thereby performing ablation. The radio frequency electrode ablation catheter of the present invention allows the cooling liquid injected from the proximal end to flow out from the cooling liquid discharge lumen and be discharged through the discharge port of the cooling liquid discharge lumen formed at the side of the main body. The position of the discharge port is located in the coronary sinus, the right atrium or the superior vena cava (or the inferior vena cava), so that the cooling liquid flows to the coronary sinus, the right atrium or the vein.

[0089] Reference Figure 2 The outlet of the coolant outlet lumen for discharging the coolant is located at CS1, CS2, CS3, RA or SVC indicated by the red arrow. Here, CS1, CS2, CS3, RA, SVC only mean the approximate position of the outlet, but do not mean that the exact position must be limited to this. That is, the outlet for discharging the coolant can be located at a certain point between CS, RA, SVC (or IVC).

[0090] Figure 3 is an overall stereoscopic view, a partial enlarged view and a partial cross-sectional view of a radiofrequency electrode ablation catheter for ventricular septum therapy according to an embodiment of the present invention, and Figure 4 It is a cross-sectional view and a partial magnified view of the radiofrequency electrode ablation catheter.

[0091] Reference Figure 3 and Figure 4The radio frequency electrode ablation catheter 100 is roughly divided into a body part 130 (body part) and an intra-septal part 120 (intra-septal part).

[0092] The intra-septal part 120 is formed at the distal part of the main body 130 and is inserted into the interventricular septum. The thickness of about 3 to 6 Fr (preferably about 4 Fr) is a size that reduces damage to the interventricular septum when inserted into the interventricular septum.

[0093] The intra-septal part 110 includes an electrode 124 (electrode) having one or more electrodes formed on the surface, and a tapered tip 122 (tissue penetrating tip) which gradually tapers toward the distal end so as to be able to penetrate and enter the interventricular septum.

[0094] Preferably, the length of the tapered tip 122 is about 5 to 20 mm (preferably about 10 mm), and the end has a thickness of about 1.2 to 1.4 Fr. The opposite side of the end has the same thickness as the outer shape of the spacer insert (preferably 3 to 6 Fr, and more preferably 4 to 5 Fr). The tapered tip 122 is a very long and thin tip shape that is 5 to 20 times longer than the thickness of the opposite side of the end (i.e., the thickness of the outer shape of the spacer insert).

[0095] The RF ablation catheter 100 has a guidewire lumen into which a guidewire is inserted, so that the catheter can be inserted into the ventricular septum along the guidewire positioned at the ventricular septum. An inlet 112 of the guidewire lumen 110 is formed at the end of the septum insertion portion.

[0096] Preferably, the guide wire and the entrance 112 of the guide wire lumen should be closely attached to each other without any space, that is, the guide wire and the tip end should have a high precision structure without mismatch.

[0097] The reason why there should be no space between the entrance of the guidewire lumen and the guidewire is that when the tip enters the interior of the ventricular septum, no damage should be applied to the ventricular septum tissue and resistance should be minimized. This is because the tapered tip 122 in the present invention needs to penetrate and enter the ventricular septum tissue while performing the function of a needle. However, in the case where there is a space between the entrance of the guidewire lumen and the guidewire, when the tapered tip is inserted into the ventricular septum, the tip will encounter resistance due to the ventricular septum tissue, and thus the problem of possible damage to the ventricular septum tissue may occur.

[0098] Since the RF electrode ablation catheter needs to be inserted into the ventricular septum along the guide wire, the entrance of the guide wire lumen will be in close contact with the guide wire. However, it should be understood that the RF electrode ablation catheter needs to be able to pass through the guide wire lumen and move along the guide wire.

[0099] The intra-septal part is provided with at least one electrode, which not only senses the electrical signal of the myocardium or applies electrical stimulation, but also transmits the radio frequency energy of the radio frequency generator.

[0100] The electrodes are connected to the electrode wires ( Figure 5 , Figure 6 The electrode wire is connected to the proximal end along the inside or outside of the catheter and exposed to the outside, thereby connecting to the external connector. Depending on where the external connector is connected, the electrode can not only perform radio frequency high-frequency radiation, but also perform multiple functions such as electrical signal sensing and electrical stimulation.

[0101] In order to determine whether the electrode is positioned near the His bundle of the myocardium (i.e., to confirm the position of the conduction system), the electrode is used to directly sense the electrical signal of the myocardium or to apply electrical stimulation (pacing). In addition, in order to perform radiofrequency electrode ablation, the electrode is used to transmit the radiofrequency energy of the radiofrequency generator. That is, the electrode can be used for multiple purposes such as determining whether the electrode is positioned near the His bundle of the myocardium and transmitting radiofrequency energy.

[0102] First, when it is used to determine whether the electrode is positioned near the bundle of His of the myocardium, it is used to directly sense the electrical signal of the myocardium or to apply electrical stimulation to the myocardium. When applying electrical stimulation to the myocardium, the position of the conduction system such as the bundle of His can be indirectly confirmed by confirming the electrocardiogram of the heart rate generated by the electrical stimulation.

[0103] Although the RF ablation catheter can easily approach the ventricular septum, there is a risk of being positioned close to the His bundle in the myocardium. However, if RF ablation is performed with the electrode of the RF ablation catheter close to the His bundle in the myocardium, there is a risk of RF ablation of the heart's conduction system and damaging the heart's conduction system.

[0104] In order to prevent this, in the present invention, before implementing radiofrequency electrode ablation, it is necessary to confirm the position of the conduction system such as the His bundle through the electrode. To this end, the electrode performs a sensing or electrical stimulation (pacing) function. The electrode can be used to directly sense the electrical signal of the myocardium to confirm the position of the conduction system, or the electrode can be used to apply electrical stimulation to the myocardium and indirectly confirm the position of the conduction system such as the His bundle through the electrocardiogram of the heart rate generated thereby.

[0105] In the case where the electrode is positioned near the His bundle, it is necessary to change the position of the radiofrequency electrode ablation catheter to another position.

[0106] When the position of the electrode is sufficiently separated from the His bundle, the external connector connected to the electrode is connected to a radio frequency generator to apply radio frequency energy, thereby performing radio frequency electrode ablation.

[0107] When performing radiofrequency electrode ablation (RF ablation), the connector connected to the electrode is connected to a radiofrequency generator, and the radiofrequency energy of the radiofrequency generator is transmitted to the electrode, thereby performing radiofrequency electrode ablation (RF ablation).

[0108] In the case where the electrodes are formed into more than one, some electrodes can be used for radiofrequency electrode ablation, and the remaining electrodes can be used for sensing or electrical stimulation. That is, the plurality of electrodes can be distinguished according to the purpose, and they can be separated into electrodes used for radiofrequency electrode ablation and electrodes used for sensing or electrical stimulation.

[0109] In other cases, the electrodes may not be divided into two uses, but they may be used for sensing or electrical stimulation and also for RF ablation. That is, after the electrodes are used for sensing or electrical stimulation, the connector connected to the electrodes may be connected to a RF generator so as to be used as electrodes for applying RF energy.

[0110] In the present invention, the proximal part of the catheter is one end of the catheter, which means the end of the catheter exposed to the outside of the human body, and the distal part of the catheter is the other end of the catheter, which means the end inserted into the human body.

[0111] Although not shown, preferably, the septum insertion part 120 is formed with an insulated spiral coil wire or a braided wire inside. This is to prevent the kinking phenomenon when the septum insertion part is inserted into the ventricular septum and to improve the pushability and trackability. Pushability is the ability to transmit force from the proximal end to the distal end while reducing the kinking phenomenon, and trackability is the ability to follow complex blood vessels such as catheters. (Pushability is often understood as the ability to transmit force from the proximal end of the catheter to the distal end while minimizing or eliminating kinking. Trackability is often understood as the ability to navigate the catheter through tortuous vasculature). Both spirally wound wires and braided wires should be insulated from the electrodes or electrode wires.

[0112] Preferably, the septal insertion portion may be formed with a hydrophilic polymer coating on the surface. This is to enable the septal insertion portion to be moved more easily into the interventricular septal tissue. Compared with a soft catheter, the hydrophilic polymer coating is relatively hard, so it is easier to insert the septal insertion portion into the interventricular septal tissue. Since the electrode needs to be exposed on the surface, the hydrophilic polymer coating is not formed at the portion where the electrode is formed.

[0113] The body part 130 is a part constituting the body of the catheter. The outer diameter of the body part 130 is the same as or larger than the outer diameter of the intra-septal part 120. The body part 120 should have sufficient stiffness so that when the intra-septal part is pushed into the ventricular septum, the catheter is not kinked and can be pushed in effectively.

[0114] Preferably, similar to the spacer insert, the main body may be formed with an insulated spiral coil wire or braided wire inside, which can prevent the catheter from kinking and improve pushability and trackability.

[0115] In addition, when applying radiofrequency energy using a radiofrequency electrode ablation catheter, if the temperature rises excessively, not only charring (black spots) may occur in the ventricular septum, but also tissue damage may occur in the myocardium. In addition, barotrauma may occur due to a sudden increase in pressure in the tissue caused by the sudden combustion of the tissue and the release of gas, thereby posing the risk of cardiac perforation.

[0116] During radiofrequency electrode ablation, a coolant (normal saline) is required to cool the radiofrequency electrode ablation site. In order to cool, the coolant needs to be injected into the radiofrequency electrode ablation catheter.

[0117] The cooling liquid injected from the proximal portion may be returned to the proximal portion again after cooling the temperature of the electrode of the spacer insertion portion, or may be discharged from the side of the body portion.

[0118] Figure 3 It is an overall stereoscopic view, a partial enlarged view and a partial cross-sectional view of a radiofrequency electrode ablation catheter for ventricular septum therapy according to an embodiment of the present invention. Figure 4 It is a cross-sectional view and a partially enlarged view of a radiofrequency electrode ablation catheter for ventricular septal therapy according to an embodiment of the present invention.

[0119] Reference Figure 3 and Figure 4 ,like Figure 3 and Figure 4The RF electrode ablation catheter shown in the figure allows the cooling liquid (physiological saline) to be injected from the proximal end through the cooling liquid introduction tube cavity 140 and enter into the interior of the interval insertion portion 120 where the electrode 124 is positioned, and then flows out from the cooling liquid discharge tube cavity 150 and flows again in the opposite direction along the cooling liquid discharge tube cavity, and is discharged through the discharge port 152 of the cooling liquid discharge tube cavity 150 formed at the side of the main body 130.

[0120] When the radiofrequency electrode ablation catheter of the present invention is used for ventricular septal therapy, when the radiofrequency catheter is inserted along the guide wire, the distal end of the distal end allows the tip 122 to penetrate and enter the ventricular septum (myocardium) and be inserted into the ventricular septum. At this time, since the discharge port 152 of the cooling liquid discharge lumen 150 formed at the side of the body 130 is positioned in the coronary sinus, right atrium or vein, the discharged cooling liquid is discharged in the coronary sinus, right atrium or vein.

[0121] The guidewire lumen 110 is a lumen for inserting the guidewire, which is a necessary element for inserting the radiofrequency catheter into the target object (ventricular septum) along the guidewire. The guidewire lumen 110 passes through the interior of the septum insertion part 120 from an inlet 112 formed at the center of the tip end, and an outlet 114 is formed at the side of the body.

[0122] The outlet 114 of the guide wire lumen 110 can be formed at various positions, such as at the proximal end, the middle part, or the distal end of the body. Figure 3 and Figure 4 As shown in , the outlet 114 of the guidewire lumen is preferably formed at the proximal end of the body portion. This is to prevent the guidewire and the catheter from being separated from each other as much as possible, and to position the guidewire inside the radiofrequency catheter so that the radiofrequency catheter can be easily inserted along the guidewire.

[0123] The guidewire lumen 110 and the coolant discharge lumen 150 are not connected but separated from each other. That is, they are separated and separated from each other. This is to prevent the guidewire moving along the guidewire lumen from being hindered by the coolant flowing through the coolant discharge lumen.

[0124] Preferably, the cooling liquid discharge lumen has a structure surrounding the guide wire lumen, that is, a structure that positions the guide wire lumen inside the cooling liquid discharge lumen.

[0125] The cooling liquid introduction lumen 150 is a passage for inserting the cooling liquid into the interior of the radio frequency catheter, which is connected to the interior of the septal insertion part from the proximal end and has an open end to allow the cooling liquid to be injected from the outside. Therefore, the cooling liquid flowing in from the outside is injected into the interior of the septal insertion part.

[0126] The cooling liquid inlet lumen and the cooling liquid discharge lumen are connected to each other, and more preferably, have a structure in which the cooling liquid discharge lumen surrounds the cooling liquid inlet lumen near the spacer insertion portion (distal portion), that is, a structure in which the cooling liquid inlet lumen is positioned inside the cooling liquid discharge lumen.

[0127] After the cooling liquid injected from the proximal end through the cooling liquid introduction lumen 140 flows into the cooling liquid introduction lumen, since the end of the cooling liquid introduction lumen is opened, it will flow out of the cooling liquid introduction lumen and flow along the inside of the cooling liquid discharge lumen surrounding the cooling liquid introduction lumen.

[0128] Since the RF electrode is positioned outside the septal insertion part and the end of the coolant introduction lumen is connected to the inside of the septal insertion part, the coolant can be injected into the septal insertion part and cool the electrode and the catheter. In addition, since the end of the coolant discharge lumen is blocked, the coolant is discharged to the outside through the discharge port 152 formed at the side of the body part after flowing in the opposite direction along the coolant discharge lumen.

[0129] Conventional general catheters are catheters cooled with a cooling liquid (physiological saline) and have a structure in which a cooling liquid introduction lumen and a cooling liquid discharge lumen are connected from a proximal end portion to a distal end portion of the catheter.

[0130] However, in the present invention, the cooling liquid discharge lumen is not connected to the proximal end of the catheter, but has a structure in which a discharge port is formed at the side of the main body portion to discharge the cooling liquid into the coronary sinus, the right atrium or the superior vena cava (or the inferior vena cava), and the cooling liquid discharge lumen has a structure surrounding the cooling liquid introduction lumen.

[0131] Therefore, since the catheter of the present invention does not need to form a cooling liquid discharge pipe to the proximal end, it has the advantage that the outer diameter of the catheter can be reduced. In particular, in the case of a radiofrequency electrode ablation catheter for ventricular septal therapy that passes through a narrow blood vessel of the heart and targets the ventricular septum, the reduction of the outer diameter of the catheter is even more important.

[0132] In addition, by minimizing the possibility of contact with high-frequency power lines, temperature sensing lines, etc., insulation problems that may occur in the catheter can be reduced, and by shortening the length of the tube that transports saline (cooling liquid), there is the advantage of being able to inject saline with a lower pressure pump.

[0133] In addition, according to the method of applying electric potential during radio frequency electrode ablation, it is roughly divided into a method using a monopolar mode RF ablation catheter and a method using a bipolar mode RF ablation catheter.

[0134] A monopolar mode RF ablation catheter is a catheter in which only one same polarity is applied to electrodes of the catheter, and a bipolar mode RF ablation catheter is a catheter in which polarities different from each other are applied to electrodes of the catheter.

[0135] In the case of using a bipolar mode radio frequency electrode ablation catheter, no additional grounding device is required, but in the case of using a monopolar mode radio frequency electrode ablation catheter, an additional grounding device is required.

[0136] In the case of using a monopolar mode radiofrequency electrode ablation catheter, there are cases where the grounding device is positioned at other parts of the human body and cases where it is positioned within the ventricular septum.

[0137] The situation where the grounding device is positioned at other parts of the human body is that after the RF electrode ablation catheter is positioned at the interventricular septum and the grounding plate (grounding device) is grounded to other parts of the human body (parts of the human body such as the back, buttocks, calves, etc.), RF energy is applied to the electrodes of the RF electrode ablation catheter to implement RF electrode ablation.

[0138] The situation where the grounding device is positioned within the interventricular septum is a method for performing radiofrequency electrode ablation by applying radiofrequency energy to the electrode of the radiofrequency electrode ablation catheter after the radiofrequency electrode ablation catheter is positioned at the interventricular septum and around the electrode of the radiofrequency electrode ablation catheter where the grounding device performs a grounding function.

[0139] Although in Figure 3 and Figure 4 , but only one electrode may be formed for radiofrequency ablation (RF ablation), and in this case, it is equivalent to a monopolar mode. In the case where one electrode is formed at the septal insertion portion, there is Figure 3 Electrodes having a width as wide as the size of 3 to 4 electrodes shown in the figure are formed.

[0140] In addition, if Figure 3 and Figure 4As shown in , the guide wire lumen may also be formed inside the cooling liquid discharge lumen, but is not necessarily limited thereto.

[0141] The inside of the coolant discharge lumen may not pass through and be positioned adjacent. That is, the guide wire lumen may not pass through the inside of the coolant discharge lumen and may be formed to be separated. In this case, although the diameter of the coolant discharge lumen is reduced, since the guide wire lumen does not move left and right in the coolant discharge lumen, it has a more stable structure.

[0142] Figure 5 The shape of the electrode wire formed on the surface of the radio frequency electrode ablation catheter and the catheter for ventricular septal therapy according to an embodiment of the present invention are shown.

[0143] Figure 5 The radiofrequency ablation catheter for ventricular septal therapy shown in shows a structure with four electrodes. Preferably, the width of the electrode is about 1mm to 10mm. Each of the four electrodes is connected to a corresponding electrode wire, and is connected to a thermocouple wire for measuring the temperature of the distal end of the catheter. The electrode wire (electrode wire) and the thermocouple wire (thermocouple wire) are connected in the proximal portion of the catheter. Although each of the four electrodes has a width of about 1mm, it is not necessarily limited to this, and can be appropriately adjusted according to the number of electrodes. When the number of electrodes is small, electrodes with relatively large width are used, and when the number of electrodes is large, the width of the electrode can be reduced. In addition, electrodes with different widths can be used in one catheter.

[0144] The radio frequency energy supplied to the electrode is realized by a silver wire spirally wound on the surface of the catheter. That is, the radio frequency energy for implementing radio frequency ablation is supplied to the electrode 124 (electrode) through an electrode wire spirally wound on the surface of a catheter made of a soft and flexible material.

[0145] As the electrode wire for supplying radio frequency energy, silver wire is preferably used. The silver wire is insulated (coated) with a plastic material that is harmless to the human body. The radio frequency ablation catheter of the present invention is inserted into the human body (coronary sinus, right atrium, vein). The electrode wire is a structure surrounding the surface of the catheter. When the catheter is inserted into the coronary sinus, right atrium or vein, the electrode wire contacts the tissue when the coating falls off, so materials such as copper that are harmful to the human body cannot be used. Therefore, in the present invention, silver wire that is harmless to the human body is used as the electrode wire.

[0146] In the present invention, by forming a silver wire as an electrode wire for transmitting radio frequency energy in a spiral shape on the surface of the catheter, it is possible to obtain advantages of being able to improve the linearity of the catheter and improve pushability.

[0147] In addition, if Figure 5 As shown in FIG. 1 , in addition to the silver wire as the electrode wire, the thermocouple wire is spaced apart from the electrode wire and is wound on the surface of the catheter in the radial direction (spiral wrapped). The thermocouple wire is also wrapped with a harmless plastic material.

[0148] Thermocouple wire is used to measure the temperature around the electrode. That is, the thermocouple wire is a wire used as a thermoelectric thermometer. The thermocouple wire is a form in which two wires are wrapped around each other, which are separated from the electrode wire (silver wire) and are wrapped around the surface of the catheter in the radial direction. Although the thermocouple wire is wrapped as a whole, the coating at its end is stripped and connected to each other to be used as a thermoelectric thermometer.

[0149] Although various thermocouple wires are currently used, in the present invention, it is preferred that the thermocouple wires be wound around the surface of a catheter inserted into the human body, and thus nickel-chromium (Nickel-Chromium) / nickel-alumel (Nickel-Alumel) wires are used, which are harmless to the human body even if the coating of the thermocouple wire falls off. That is, one of the thermocouple wires is a nickel-chromium (Nickel-Chromium) wire that is harmless to the human body, and the other is a nickel-aluminum (Nickel-Alumel) wire that is harmless to the human body.

[0150] The thermocouple wire of the present invention is also wound in a spiral shape on the surface of the catheter, thereby achieving advantages of being able to improve the linearity of the catheter and improving pushability.

[0151] As described above, the number of electrodes may be changed, and according to the number of electrodes, the number of electrode lines supplying power to the electrodes may also be changed.

[0152] Figure 6 The shape of an electrode wire formed on the surface of a radio frequency electrode ablation catheter and a catheter for ventricular septal therapy according to another embodiment of the present invention are shown. Figure 6 The case where one electrode is used is shown.

[0153] Reference Figure 6The electrode is formed into a wide electrode 124 (electrode) wound into a coil. Since there is one electrode, the electrode wire that supplies RF energy to the electrode is also formed into one. The electrode wire is coated and spirally wound on the surface of the catheter. The material can be silver wire that is safe for the human body even if the coating falls off.

[0154] The thermocouple wire for measuring the temperature of the distal end of the catheter excluding the electrode wire is wound in a spiral shape on the surface of the catheter. The thermocouple wire also has a structure in which it is coated and wound in a spiral shape on the surface of the catheter in a state where two wires are twisted and wound around each other. The structure and material of the thermocouple wire are as described above.

[0155] As described above, in a state where the electrode of the radiofrequency electrode ablation catheter is positioned in the interventricular septum, a cooling liquid is inserted into the radiofrequency electrode ablation catheter and radiofrequency electrode ablation is performed. After the radiofrequency electrode ablation is performed and the target therapeutic effect is fully obtained, all devices are removed, thereby completing the radiofrequency electrode ablation for interventricular septal therapy.

[0156] Although the embodiments of the present invention are described with reference to the above content and the accompanying drawings, it should be understood that a person skilled in the art of the present invention can implement the present invention in other specific forms without changing the technical concept or essential features of the present invention. Therefore, the embodiments described above should be understood to be exemplary in all aspects, rather than restrictive.

Claims

1. A radiofrequency catheter for ventricular septal therapy, characterized in that: include: A septal insertion portion, wherein the septal insertion portion has a tip formed at the distal end of the distal end portion and tapered to penetrate and be inserted into the interventricular septum, and one or more electrodes are formed on the outer peripheral surface at a position adjacent to the tip; as well as The main body is made of a soft and flexible material and has a guide wire lumen that penetrates the interior of the spacer insertion portion from the center of the tip end so that a guide wire can be inserted, a coolant introduction lumen that is connected from the proximal end to the interior of the spacer insertion portion so that coolant can be injected from the outside, and a coolant discharge lumen that is connected to the coolant introduction lumen and has a discharge port formed at the side. wherein the spacing insertion portion penetrates and is inserted into the myocardium under the guidance of the guide wire, the cooling liquid introduction lumen has an open end, and the cooling liquid discharge lumen has a structure surrounding the cooling liquid introduction lumen, wherein the guide wire lumen and the cooling liquid introduction lumen are not connected to each other and are separated from each other, the guide wire lumen and the cooling liquid discharge lumen are not connected to each other and are separated from each other, and the discharge outlet of the cooling liquid discharge lumen is arranged to be separated from the outlet of the guide wire lumen, The cooling liquid discharge lumen has a structure surrounding the cooling liquid introduction lumen, and the cooling liquid injected along the cooling liquid introduction lumen flows along the cooling liquid discharge lumen surrounding the cooling liquid introduction lumen in a direction opposite to the injection direction, and is discharged into the coronary sinus, right atrium or vein through a discharge port connected to the cooling liquid discharge lumen.

2. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: The cooling liquid discharge lumen has a structure surrounding the guide wire lumen, and The guide wire lumen passes through the coolant exhaust lumen.

3. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: The guidewire lumen does not pass through the interior of the coolant drain lumen but is positioned adjacent to the coolant drain lumen.

4. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: The electrode performs the functions of connecting to a radio frequency generator to receive radio frequency energy and radiating radio frequency energy, and performs the functions of sensing electrical signals of the myocardium or applying electrical stimulation.

5. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: The guide wire lumen and the guide wire passing through the inside are closely attached to each other without any space between them.

6. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: The spacer inserting portion has a spiral coil wire or a braided wire formed therein, and the coil wire or the braided wire is insulated from the electrode.

7. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: The spacer inserting portion is formed with a hydrophilic polymer coating at a surface portion other than a surface of the electrode.

8. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: One end of the guide wire lumen is formed at the distal end center of the tip, and the other end thereof is formed at the side of the radio frequency catheter or at the distal end of the proximal portion of the radio frequency catheter.

9. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: The tapered tip has a length of 5 to 20 mm, an end of the tip has a thickness of 1.2 to 1.4 Fr, and an opposite side of the end of the tip has a thickness of 3 to 6 Fr.

10. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: Electrode wires that transmit radio frequency energy to the electrodes are coated and wound on the surface of the radio frequency catheter in a radial direction, and electrode wires corresponding to the number of the electrodes are connected.

11. The radiofrequency catheter for ventricular septal therapy according to claim 10, characterized in that: The electrode wires are silver wires.

12. The radiofrequency catheter for ventricular septal therapy according to claim 1, characterized in that: From the proximal end portion to the distal end portion, two thermocouple wires are wound on the surface of the radio frequency catheter in a radial direction in a state of being wound around each other to measure the temperature of the electrode.

13. The radiofrequency catheter for ventricular septal therapy according to claim 12, characterized in that: One of the thermocouple wires is a nickel-chromium wire that is harmless to the human body, and the other is a nickel-aluminum alloy wire that is harmless to the human body.

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