Cryoablation catheter

Abstract

The cryoablation catheter comprises a balloon catheter, a mapping catheter and a supporting catheter, and the balloon catheter comprises an inner tube, an outer tube, a balloon, an injection tube located between the inner tube and the outer tube and a recovery tube located between the inner tube and the outer tube. When the cryoablation catheter is used, the mapping section can be close to the balloon as much as possible, so that the mapping position is closer to the actual ablation position, and the mapping result is more accurate. And the supporting catheter can limit the movement of the mapping catheter, so that the phenomenon that the mapping section is too close to the balloon and is frozen, and the mapping effect is affected is avoided. And a first temperature sensor and a second temperature sensor are arranged, so that feedback can be provided for operation, and the operation is helped to be more accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and more particularly, to a cryoablation catheter. Background Art

[0002] Cryoablation is mainly used for treating arrhythmia. Compared with other ablation methods such as radiofrequency ablation and laser ablation, cryoablation has advantages of high safety, simple operation, and patient comfort, and has become one of the mainstream choices for atrial fibrillation ablation. Existing cryoablation surgeries mainly use balloon catheters, mapping catheters, etc. During operation, the balloon of the balloon catheter is required to block the pulmonary vein ostium, and at the same time of cryoablation, the mapping catheter is used to measure the electrodes at the pulmonary vein ostium. However, for existing mapping catheters, when mapping, the mapping ring will extend into a relatively deep position of the pulmonary vein ostium, so that the actual mapping position of the mapping ring is far from the balloon ablation position, resulting in inaccurate measurement values of the mapping electrodes.

[0003] Some surgical methods will, after cryoablation, cancel the blockage of the pulmonary vein ostium by the balloon and use the mapping guide roller to map the ablation position. If the ablation effect is relatively good after detection, the surgery is completed and the balloon catheter is withdrawn. If the ablation is incomplete after detection, the pulmonary vein ostium is blocked again by the balloon, and the contrast agent is injected again, and the previous cryoablation operation is repeated. Although this method can achieve relatively accurate mapping, the operation is more cumbersome, and blocking the pulmonary vein ostium itself has a certain degree of difficulty. Multiple operations further increase the difficulty, and the longer operation duration and more use of contrast agent are disadvantageous to the patient.

[0004] Therefore, during cryoablation, due to the defect in the position of the mapping ring, it is difficult to achieve a very accurate standard, so the mapping result is inaccurate and cannot fully show the ablation effect. Summary of the Invention

[0005] The present invention aims to overcome the defects of the prior art and provides a cryoablation catheter.

[0006] To achieve the above object, the present invention provides the following technical solution: A cryoablation catheter, comprising a balloon catheter, a mapping catheter, and a support catheter. The balloon catheter includes an inner tube, an outer tube, a balloon, an injection tube located between the inner tube and the outer tube, and a recovery tube located between the inner tube and the outer tube. The support catheter is inserted into the inner tube and can extend from the front end of the inner tube. The support catheter includes a main tube portion and a plurality of support portions connected to the main tube portion. When there is no external force, the support portion includes an extension unit connected to the main tube portion, a first support unit connected to the extension unit, a transition unit connected to the first support unit, and a second support unit connected to the transition unit. The mapping catheter is inserted into the main tube portion and can extend from the front end of the main tube portion. The mapping catheter includes a pushing section and a working section. When there is no external force, the working section includes a first connection section connected to the pushing section, a limiting section connected to the first connection section, a second connection section connected to the limiting section, and a mapping section connected to the second connection section. A plurality of mapping electrodes are provided at the mapping section.

[0007] Further, shape memory alloys are provided in both the support portion and the working section.

[0008] Thus, the support catheter extends from the front end of the balloon catheter and unfolds under the action of the shape memory alloy, and the mapping catheter extends from the front end of the main tube portion and unfolds under the action of the shape memory alloy.

[0009] Further, the support portion has a cladding covering the shape memory alloy.

[0010] Further, a first temperature sensor is installed at the transition unit, and a second temperature sensor is installed at the second support unit.

[0011] Further, a first wire connected to the first temperature sensor and a second wire connected to the second temperature sensor are provided in the support catheter.

[0012] Further, the first temperature sensor is installed on the surface of the transition unit away from the balloon.

[0013] Further, the second temperature sensor is installed on the surface of the second support unit away from the balloon.

[0014] Further, the limiting section is in a spiral ring shape.

[0015] Further, the mapping section is in a ring shape.

[0016] Further, when the first support unit is pressed by the limiting section, the transition unit of the support portion where the first support unit is located can abut against the surface of the inflated balloon.

[0017] Further, when the second support unit is pressed by the mapping section, the second support unit can abut against the transition unit of the support portion where the second support unit is located.

[0018] Further, the mapping section is in the shape of a ring with an opening.

[0019] Further, there are four support portions, which are evenly distributed in a ring.

[0020] Further, the number of mapping electrodes of the mapping section is greater than or equal to 8.

[0021] Further, a spiral injection tube is connected to the front end of the injection tube, and there are a plurality of spray holes in the injection tube.

[0022] Further, when there is no external force, the outer diameter of the limiting section is less than or equal to one-third of the outer diameter of the mapping section.

[0023] Beneficial effects:

[0024] 1. For the cryoablation catheter of the present application, during use, the mapping section can move closer to the balloon as much as possible, so that the position of mapping is closer to the actual ablation position, and thus the mapping result is more accurate.

[0025] 2. The support catheter of the present application can limit the movement of the mapping catheter, thereby preventing the mapping section from being frozen due to being too close to the balloon and affecting the mapping effect.

[0026] 3. The cryoablation catheter of the present application is provided with a first temperature sensor and a second temperature sensor, so as to provide feedback for the operation and help the operation to be more accurate. Description of the drawings

[0027] Figure 1 It is a schematic diagram of the balloon being inflated after the support catheter and the mapping catheter are both deployed; Figure 2 It is an enlarged view of area A; Figure 3 It is on Figure 1 On this basis, it is a schematic diagram of moving the support catheter backward to the balloon; Figure 4 It is an enlarged view of area B; Figure 5 It is on Figure 3 On this basis, it is a schematic diagram of moving the mapping catheter backward and being supported by the first support unit; Figure 6 It is an enlarged view of area C; Figure 7 It is a schematic diagram of the separation of the balloon catheter, the support catheter and the mapping catheter components; Figure 8 It is an enlarged view of area D; Figure 9 It is an enlarged view of region E; Figure 10 It is a schematic diagram of the separation of the balloon catheter, the support catheter, and the mapping catheter components, where the balloon catheter shows a sectional view; Figure 11 It is an enlarged view of region F; Figure 12 It is an enlarged view of region G.

[0028] Description of reference numerals: balloon catheter 1; inner tube 1.1; outer tube 1.2; balloon 1.3; injection tube 1.4; recovery tube 1.5; mapping catheter 2; pushing section 2.1; first connection section 2.2; limiting section 2.3; second connection section 2.4; mapping section 2.5; mapping electrode 2.6; support catheter 3; main tube portion 3.1; extension unit 3.2; first support unit 3.3; transition unit 3.4; second support unit 3.5; first temperature sensor 3.6; second temperature sensor 3.7; injection tube 4. Specific implementation manners

[0029] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention, and should not be construed as a limitation to the present invention.

[0030] The present invention provides a cryoablation catheter as shown in the figure, which includes a balloon catheter 1, a mapping catheter 2, and a support catheter 3. The balloon catheter 1 includes an inner tube 1.1, an outer tube 1.2, a balloon 1.3, an injection tube 1.4 located between the inner tube 1.1 and the outer tube 1.2, and a recovery tube 1.5 located between the inner tube 1.1 and the outer tube 1.2. The support catheter 3 is inserted into the inner tube 1.1 and can extend from the front end of the inner tube 1.1. The support catheter 3 includes a main tube portion 3.1 and a plurality of support portions connected to the main tube portion 3.1. When there is no external force, the support portion includes an extension unit 3.2 connected to the main tube portion 3.1, a first support unit 3.3 connected to the extension unit 3.2, a transition unit 3.4 connected to the first support unit 3.3, and a second support unit 3.5 connected to the transition unit 3.4. The mapping catheter 2 is inserted into the main tube portion 3.1 and can extend from the front end of the main tube portion 3.1. The mapping catheter 2 includes a pushing section 2.1 and a working section. When there is no external force, the working section includes a first connection section 2.2 connected to the pushing section 2.1, a limiting section 2.3 connected to the first connection section 2.2, a second connection section 2.4 connected to the limiting section 2.3, and a mapping section 2.5 connected to the second connection section 2.4. A plurality of mapping electrodes 2.6 are provided at the mapping section 2.5. Shape memory alloy is provided in both the support portion and the working section. A first temperature sensor 3.6 is installed at the transition unit 3.4, and a second temperature sensor 3.7 is installed at the second support unit 3.5. The first temperature sensor 3.6 is installed on the surface of the transition unit 3.4 away from the balloon 1.3. The second temperature sensor 3.7 is installed on the surface of the second support unit 3.5 away from the balloon 1.3. The limiting section 2.3 is in a spiral ring shape; the mapping section 2.5 is in a ring shape; when the first support unit 3.3 is pressed by the limiting section 2.3, the transition unit 3.4 of the support portion where the first support unit 3.3 is located can abut against the surface of the inflated balloon 1.3; when the second support unit 3.5 is pressed by the mapping section 2.5, the second support unit 3.5 can abut against the transition unit 3.4 of the support portion where the second support unit 3.5 is located.

[0031] There are four support portions, which are evenly distributed in a ring shape. The number of mapping electrodes 2.6 on the mapping section 2.5 is greater than or equal to 8. The front end of the injection tube 1.4 is connected to a spiral injection tube 4, and a plurality of spray holes are provided at the injection tube 4. When there is no external force, the outer diameter of the limiting section 2.3 is less than or equal to one-third of the outer diameter of the mapping section 2.5.

[0032] Working principle: As shown in the figure, when the cooling ablation catheter of the present application is in use, the support catheter is extended from the front end of the balloon catheter and deployed under the action of the shape memory alloy, and the mapping catheter is extended from the front end of the main tube portion and deployed under the action of the shape memory alloy. And the balloon is used to block the pulmonary vein ostium (the balloon mainly uses the position of a circle at the front end of the balloon for cryoablation of the pulmonary vein ostium. Subsequently, the support portion will abut against the surface of the balloon, but the abutting position is closer to the front end relative to the circle position for ablation and will not interfere with the ablation position). Then, the support catheter is moved backward, so that the transition unit of the support catheter abuts against the outer surface of the balloon, thereby realizing positioning between the plurality of support portions and the balloon. Then, the mapping catheter is moved backward, so that the limiting section can abut against the first support unit (the limiting section does not need to abut against the first support units of all the support portions, and only needs to abut against the first support unit of at least one support portion). At this time, the mapping section does not abut against the second support units of all the support portions. Thus, at this time, the mapping section can detect the electrical signal of the position of the pulmonary vein ostium, and the detection position is relatively close to the ablation position of the balloon, so the detection is more accurate. And due to the limitation of the support catheter, the mapping section will not contact the balloon or be too close to the balloon, thereby avoiding the temperature at the mapping electrode being too low and affecting the detection. And during the freezing process, when the limiting section abuts against the first support unit of at least one support portion (which has a certain pressing effect on this support portion), it can make the transition unit of this support portion abut against the balloon, so that the temperature detected by the first temperature sensor is very low. Thus, according to the detected temperature of the first temperature sensor, it can be judged whether the transition unit abuts against the balloon (during the operation, the transition unit of at least one support portion needs to abut against the surface of the balloon to ensure the positioning between the support catheter and the balloon). Thus, it shows that the position of the mapping section relative to the balloon is more appropriate and meets the operation requirements at this time. And there is a gap between the mapping section and the second support unit and they do not contact. And since the second support unit does not contact the surface of the balloon, there is a certain difference between the measured value of the second temperature sensor and the measured value of the first temperature sensor. However, when the mapping catheter is operated improperly and moved backward too much, the mapping section will abut against and press the second support unit, which will cause the second support unit to abut against the transition unit. Thus, due to the second support unit abutting against the transition unit, there is more direct contact and heat transfer between them, and the second temperature sensor is closer to the first temperature sensor, so the gap between the measured values of the second temperature sensor and the first temperature sensor becomes significantly smaller. Thus, according to the difference between the second temperature sensor and the first temperature sensor, it can be judged that the mapping catheter has been moved backward too much and is too close to the balloon, thus reminding the operator to move the mapping catheter forward as much as possible to a more appropriate position. Thus, in this way, when the balloon is used for cryoablation, the mapping section is in a more appropriate position, which can be relatively close to the ablation position and will not be too close to the balloon.

[0033] Although the present invention has been illustrated and described with reference to preferred embodiments, those skilled in the art should understand that various changes and modifications can be made to the present invention as long as they do not exceed the scope defined by the claims of the present invention.

Claims

1. A cryoablation catheter, characterized in that, It includes a balloon catheter, a mapping catheter, and a support catheter. The balloon catheter includes an inner tube, an outer tube, a balloon, an injection tube located between the inner tube and the outer tube, and a recovery tube located between the inner tube and the outer tube; the support catheter is inserted into the inner tube and can extend from the front end of the inner tube. The support catheter includes a main tube portion and a plurality of support portions connected to the main tube portion. When there is no external force, each support portion includes an extension unit connected to the main tube portion, a first support unit connected to the extension unit, a transition unit connected to the first support unit, and a second support unit connected to the transition unit; the mapping catheter is inserted into the main tube portion and can extend from the front end of the main tube portion. The mapping catheter includes a pushing section and a working section. When there is no external force, the working section includes a first connection section connected to the pushing section, a limiting section connected to the first connection section, a second connection section connected to the limiting section, and a mapping section connected to the second connection section. There are a plurality of mapping electrodes at the mapping section.

2. The cryoablation catheter according to claim 1, wherein Both the support portion and the working section are made of shape memory alloy.

3. The cryoablation catheter according to claim 1, wherein A first temperature sensor is installed at the transition unit, and a second temperature sensor is installed at the second support unit.

4. The cryoablation catheter according to claim 3, wherein The limiting section is in a spiral ring shape; the mapping section is in a ring shape; when the first support unit is pressed by the limiting section, the transition unit of the support portion where the first support unit is located can abut against the surface of the inflated balloon; when the second support unit is pressed by the mapping section, the second support unit can abut against the transition unit of the support portion where the second support unit is located.

5. The cryoablation catheter according to claim 1, wherein, There are four support portions, which are evenly distributed in a ring shape.

6. The cryoablation catheter according to claim 1, wherein The number of mapping electrodes at the mapping section is greater than or equal to 8.

7. The cryoablation catheter according to claim 1, characterized in that, The front end of the injection tube is connected to a spiral injection pipe, and there are a plurality of spray holes at the injection pipe.

8. The cryoablation catheter according to claim 4, wherein When there is no external force, the outer diameter of the limiting section is less than or equal to one-third of the outer diameter of the mapping section.

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