Three-dimensional mapping catheter

Abstract

The utility model relates to a three-dimensional mapping catheter which comprises a flexible tube, an extension shaft arranged in the flexible tube and longitudinally extending along a tube cavity of the flexible tube, a handle arranged at the near end of the flexible tube and a far-side cap fixedly connected with the far end of the extension shaft, and a three-dimensional mapping assembly is arranged at the far end of the flexible tube. The three-dimensional mapping assembly comprises a plurality of flexible splines, the flexible splines are controlled to be unfolded and folded through inhaul cables, the far ends of the flexible splines are fixedly connected with the far-side cap, each flexible spline is provided with a plurality of auxiliary ultrasonic positioning devices, the extension shaft is provided with a main ultrasonic positioning device, and the main ultrasonic positioning device is provided with a plurality of auxiliary ultrasonic positioning devices. A magnetic positioning assembly is disposed within the distal cap.

Description

Technical Field

[0001] The present invention relates to the field of cardiac electrophysiological mapping and ablation, and particularly to a three-dimensional mapping catheter. Background Art

[0002] Atrial fibrillation (AF) is the most common persistent arrhythmia, and its existence will seriously affect the quality of life of patients, significantly increasing the risks of death, stroke, heart failure and dementia. Catheter ablation is the main treatment method for rhythm control of AF. In order to better achieve catheter ablation treatment, a mapping system is usually required. Currently, the mapping technology widely recognized clinically is the two-dimensional mapping system. The two-dimensional mapping system needs to be carried out under the guidance of X-ray images, and point-by-point mapping needs to be performed on the endocardium through an electrode catheter. However, this method can only obtain a two-dimensional view. When performing point-by-point ablation, the multi-point connection can only be operated based on the personal experience and memory of the doctor, which has high requirements for the doctor, large errors in clinical effects and long time consumption.

[0003] Based on the problems existing in two-dimensional mapping, many companies have newly developed three-dimensional mapping systems. Currently, the commonly used three-dimensional mapping methods include magnetic positioning, electrical positioning, and electromagnetic combined positioning.

[0004] The magnetic positioning system generally includes a positioning plate, magnetic patches, a catheter and a triaxial sensor. Among them, the coil in the positioning plate generates a magnetic field, and the magnetic field strength is inversely proportional to the distance from the coil. The closer to the magnetic field, the stronger the strength. The magnetic patch is placed on the patient's back, and the relative position of the center of the back patch corresponds to that of the positioning plate, serving as the origin of the coordinate system and providing an accurate fixed reference point. In the coordinate system, each point has its own individual magnetic field strength. When the catheter with a magnetic positioning sensor is inserted into the patient's heart, the system can determine the current orientation and position coordinates of the catheter according to the magnetic field strength measured by the magnetic positioning sensor. The disadvantage of magnetic positioning is that the magnetic field strength at a fixed position will be interfered by the ablation electrode, resulting in a change in the magnetic field strength at this position in the original model, thus affecting the mapping effect.

[0005] The electrical positioning system mainly consists of a current generator and six patches. The six patches are divided into three groups and are respectively pasted on the patient's chest and back to construct a spatial coordinate system. The current generated by the system is transmitted to the electrodes of the catheter, and each electrode emits a sine wave electrical signal at a specific frequency. When the catheter is inserted into the patient's heart, the six patches respectively collect the current emitted by the catheter and measure the current intensity at each patch in real time. Each position corresponds to a different current intensity. The disadvantage of electrical positioning is that due to the differences in impedance and propagation speed at various positions of blood, muscle, bone and heart cavities in the heart, as well as the instability and inaccuracy caused by the patient's breathing, the electrical signal imaging will have corresponding deformations, and inaccurate 3D models will occur.

[0006] The electromagnetic positioning system combines the technologies of magnetic positioning and electrical positioning, and corrects the data with each other to obtain the catheter orientation and position information. The structure of this system is complex. Summary of the Invention

[0007] In view of the above analysis, the purpose of the present utility model is to provide a three-dimensional mapping catheter, which has magnetic positioning and ultrasonic ranging means to solve problems such as large mapping errors and complex structures.

[0008] The purpose of the present utility model is achieved through the following technical solutions:

[0009] A three-dimensional mapping catheter includes a flexible tube, an extension shaft disposed within the flexible tube and longitudinally extending along its lumen, a handle disposed at the proximal end of the flexible tube, and a distal cap fixedly connected to the distal end of the extension shaft. A three-dimensional mapping assembly is disposed at the distal end of the flexible tube. The three-dimensional mapping assembly includes a plurality of flexible splines, and the flexible splines are controlled to expand and contract by cables. The distal ends of the flexible splines are fixedly connected to the distal cap. A plurality of secondary ultrasonic positioning devices are disposed on each flexible spline. A primary ultrasonic positioning device is disposed on the extension shaft. A magnetic positioning assembly is disposed within the distal cap.

[0010] Further, 2 - 64 of the secondary ultrasonic positioning devices are disposed on each flexible spline, the spacing between the secondary ultrasonic positioning devices on each flexible spline is the same, and the distances from the secondary ultrasonic positioning devices at both ends of the flexible spline to the proximal end of the distal cap and the distal end of the flexible tube are also the same.

[0011] Further, the secondary ultrasonic positioning device is a sheet structure and is fixed to the outer surface of the flexible spline.

[0012] Further, the secondary ultrasonic positioning device includes a secondary ultrasonic buffer and sound-absorbing layer, an outer layer of the secondary ultrasonic positioning device that wraps the secondary ultrasonic buffer and sound-absorbing layer, a secondary ultrasonic transducer disposed within the secondary ultrasonic buffer and sound-absorbing layer, and a secondary driver connected to the secondary ultrasonic transducer. The secondary driver is connected to a cable interface disposed at the proximal end of the handle through an insulated electrical wire.

[0013] Further, the primary ultrasonic positioning device is annularly fixed on the extension shaft. The primary ultrasonic positioning device includes a primary ultrasonic buffer and sound-absorbing layer, an outer layer of the primary ultrasonic positioning device that wraps the primary ultrasonic buffer and sound-absorbing layer, a primary ultrasonic transducer disposed within the primary ultrasonic buffer and sound-absorbing layer, and a primary driver connected to the primary ultrasonic transducer. The primary driver is connected to a cable interface disposed at the proximal end of the handle through an insulated electrical wire.

[0014] Further, when several of the flexible splines are expanded into a spherical shape, the main ultrasonic positioning device and the plurality of sub-ultrasonic positioning devices are coplanar, and the main ultrasonic positioning device is located at the center of the plane.

[0015] Further, there are several main ultrasonic positioning devices, and the plurality of sub-ultrasonic positioning devices are respectively arranged in different planes, and each main ultrasonic positioning device is respectively located at the center of a different plane.

[0016] Further, the magnetic positioning assembly includes a first sensor, a second sensor, and a third sensor, and the magnetic positioning assembly is used in cooperation with an external positioning plate.

[0017] Further, the magnetic positioning assembly is connected to a cable interface arranged at the proximal end of the handle through an insulated electric wire.

[0018] Further, a knob is arranged on the handle, the cable is arranged inside the flexible spline, the proximal end of the cable is fixedly connected to the knob, and the knob is used to adjust the length of the cable so as to control the shape of the flexible spline.

[0019] Compared with the prior art, the present utility model can at least achieve one of the following beneficial effects:

[0020] 1. The present application uses the magnetic positioning technology at each point in the magnetic field to establish a three-dimensional coordinate system, and determines the position and direction of the catheter by using the characteristic that the magnetic field intensity at each point in the magnetic field is different. At the same time, the ultrasonic ranging technology is introduced into the three-dimensional mapping, and the ultrasonic ranging is used to measure the distance between the catheter and the tissue for drawing a three-dimensional image.

[0021] 2. Different from the dot-shaped or flat-shaped mapping catheters in the prior art, the unfolded state of the three-dimensional mapping assembly of the present application is set to be spherical. And the ultrasonic positioning devices are divided into primary and secondary. The sub-ultrasonic positioning devices are sheet-shaped and located on the outer surface of the flexible spline, and the main ultrasonic positioning device is annular and wrapped around the extension shaft. The sub-ultrasonic positioning device can only measure the tissue distance in one direction, and the directions and quantities that the main ultrasonic positioning device can measure are the same as the quantity of the sub-ultrasonic positioning devices arranged on the flexible spline (for example, if sub-ultrasonic positioning devices are arranged on 6 flexible splines, then one main ultrasonic positioning device can measure the tissue distance in 6 directions).

[0022] In the present utility model, the above technical solutions can also be combined with each other to achieve more preferred combined solutions. Other features and advantages of the present utility model will be described in the subsequent description, and some advantages can be made obvious from the description, or can be understood by implementing the present utility model. The purpose and other advantages of the present utility model can be realized and obtained from the content specifically pointed out in the description and the drawings. Description of the Drawings

[0023] The accompanying drawings are only for the purpose of showing specific embodiments and are not considered to be a limitation of the present utility model. Throughout the drawings, the same reference signs denote the same components.

[0024] Figure 1 It is a schematic structural diagram of the distal part of the three-dimensional mapping catheter of the present application.

[0025] Figure 2 It is a schematic structural diagram of the overall structure of the three-dimensional mapping catheter of the present application.

[0026] Figure 3 and Figure 4 It is a schematic structural diagram of the auxiliary ultrasonic positioning device of the present application.

[0027] Figure 5 and Figure 6 It is a schematic structural diagram of the main ultrasonic positioning device of the present application.

[0028] Figure 7 It is a schematic structural diagram of the magnetic positioning assembly of the present application.

[0029] Figure 8 It is a schematic diagram of establishing a three-dimensional coordinate system of the three-dimensional mapping catheter with magnetic positioning and ultrasonic ranging of the present application.

[0030] Reference signs:

[0031] Wherein: 1. Three-dimensional mapping catheter; 2. External positioning plate; 11. Flexible tube; 12. Extension shaft; 13. Three-dimensional mapping assembly; 14.

[0032] Distal cap; 15. Handle; 121. Main ultrasonic positioning device; 131. Flexible spline; 132. Auxiliary ultrasonic positioning device; 141.

[0033] Magnetic positioning assembly; 151. Knob; 152. Cable; 153. Cable interface; 1211. Main ultrasonic buffer and sound insulation layer; 1212. Outer layer of the main ultrasonic positioning device; 1213. Main ultrasonic transducer; 1214. Main driver; 1321. Auxiliary ultrasonic buffer and sound insulation layer; 1322. Outer layer of the auxiliary ultrasonic positioning device; 1323. Auxiliary ultrasonic transducer; 1324. Auxiliary driver; 1411. First sensor; 1412. Second sensor; 1413. Third sensor. Detailed embodiments

[0034] In order to make the purpose, technical solutions and advantages of the present application clearer and more understandable, the following examples are given with reference to the accompanying drawings to further elaborate on the present application in detail.

[0035] As used in the present invention, "proximal end" refers to the end close to the surgical operator, and "distal end" refers to the end far from the surgical operator.

[0036] As used in the present invention, the "outer surface of the flexible spline" refers to the outer surface of the flexible spline opposite to the extension axis.

[0037] As Figure 1 As shown, a three-dimensional mapping catheter 1 includes a flexible tube 11, an extension shaft 12 disposed within the flexible tube 11 and longitudinally extending along its lumen, a handle 15 disposed at the proximal end of the flexible tube 11, and a distal cap 14 fixedly connected to the distal end of the extension shaft 12. A three-dimensional mapping assembly 13 is disposed at the distal end of the flexible tube 11. The three-dimensional mapping assembly 13 includes a plurality of flexible splines 131, preferably six flexible splines. The flexible splines 131 are controlled to expand and contract by cables. The distal ends of the flexible splines 131 are fixedly connected to the distal cap 14. Preferably, the distal ends of the flexible splines 131 are coupled to the inside of the distal cap 14. A plurality of secondary ultrasonic positioning devices 132 are disposed on each flexible spline 131. A primary ultrasonic positioning device 121 is disposed on the extension shaft 12. A magnetic positioning assembly is disposed within the distal cap 14. The three-dimensional mapping catheter 1 has two configurations: Configuration 1 and Configuration 2. In Configuration 1, each flexible spline 131 is in a contracted state, and the flexible spline 131 abuts against the extension shaft 12 and is almost parallel to the extension shaft 12, i.e., in a state like when an umbrella is closed. In Configuration 2, the middle of each flexible spline 131 expands outward, causing the three-dimensional mapping assembly 13 to expand into a spherical shape as a whole. In one embodiment, the cables are disposed within the lumen of the flexible tube 11 and extend distally along the lumen of the flexible tube 11. The proximal ends of the flexible splines 131 are fixedly connected to the cables. The proximal ends of the cables are connected to the handle 15, and the cables are controlled to slide distally along the flexible tube 11 to achieve the configuration change of the three-dimensional mapping catheter 1. This application uses the magnetic positioning technology of points in a magnetic field to establish a three-dimensional coordinate system, and determines the position and direction of the catheter by using the characteristic that the magnetic field strengths of points in the magnetic field are different. At the same time, the ultrasonic ranging technology is introduced into three-dimensional mapping, and the distance between the catheter and the tissue is measured by ultrasonic ranging for drawing a three-dimensional image.

[0038] In one embodiment, 2 - 64 secondary ultrasonic positioning devices 132 are disposed on each flexible spline 131 for measuring electrical signals. Each secondary ultrasonic positioning device disposed on each flexible spline has its own serial number. Starting from the most distal end, they are sequentially numbered 1, 2, 3... N from far to near. The spacing between the secondary ultrasonic positioning devices on each flexible spline is the same. The distances between the secondary ultrasonic positioning devices at both ends of the flexible spline and the proximal end of the distal cap and the distal end of the flexible tube are also the same. The secondary ultrasonic positioning device 132 is a sheet-like structure and is located on the outer surface of the flexible spline 131. As Figure 3 andFigure 4 As shown, the secondary ultrasonic positioning device 132 includes a secondary ultrasonic buffer and sound-absorbing layer 1321, an outer layer 1322 of the secondary ultrasonic positioning device that wraps the secondary ultrasonic buffer and sound-absorbing layer 1321, a secondary ultrasonic transducer 1323 disposed within the secondary ultrasonic buffer and sound-absorbing layer 1321, and a secondary driver 1324 connected to the secondary ultrasonic transducer 1323. The secondary driver 1324 is connected to a cable interface 153 provided at the proximal end of the handle 15 through an insulated electric wire. One end of the insulated electric wire is connected to the secondary driver, and the insulated electric wire passes through the interior of the flexible spline 131, the lumen of the flexible tube 11, and the interior of the handle 15 to be connected to the cable interface 153, and is connected to an external device through the cable interface. As Figure 1 shown, there are a plurality of primary ultrasonic positioning devices 121, which are fixedly arranged in a ring on the extension shaft 12. As Figure 5 and 6 shown, the structure of the primary ultrasonic positioning device 121 is substantially the same as that of the secondary ultrasonic positioning device 132. The secondary ultrasonic positioning device 132 is shown as a small protrusion disposed outside the flexible spline 13. The primary ultrasonic positioning device 121 is annularly embedded on the extension shaft 12 and includes a primary ultrasonic buffer and sound-absorbing layer 1211, an outer layer 1212 of the primary ultrasonic positioning device that wraps the primary ultrasonic buffer and sound-absorbing layer 1211, a primary ultrasonic transducer 1213 disposed within the primary ultrasonic buffer and sound-absorbing layer 1211, and a primary driver 1214 connected to the primary ultrasonic transducer 1213. The primary driver 1214 is connected to a cable interface 153 provided at the proximal end of the handle 15 through an insulated electric wire. One end of the insulated electric wire is connected to the primary driver 1214, and the other end of the insulated electric wire extends in the proximal direction inside the extension shaft 12 and passes through the interior of the handle 15 to be connected to the cable interface 153. The cable interface 153 is used to connect the three-dimensional mapping catheter 1 to an external device. The primary driver 1214 and the secondary driver 1324 are of a tension spring structure and are used to retract the primary ultrasonic transducer 1213 and the secondary ultrasonic transducer 1323. In one embodiment, both the primary ultrasonic transducer 1213 and the secondary ultrasonic transducer 1323 are multi-chip. The primary ultrasonic transducer 1213 and the secondary ultrasonic transducer 1323 can arrange array elements in a two-dimensional planar array, adopt a sparse array to obtain corresponding effective array elements, and the minimum number of frames per single scan is 16 frames per second. Based on the further improvement of the above three-dimensional mapping catheter, the manufacturing materials of the primary ultrasonic buffer and sound-absorbing layer 1211 and the secondary ultrasonic buffer and sound-absorbing layer 1321 are polytetrafluoroethylene.

[0039] Further, when several of the flexible splines 131 are expanded into a spherical shape, the main ultrasonic positioning device 121 and multiple secondary ultrasonic positioning devices 132 are coplanar, and the main ultrasonic positioning device 121 is located at the center of the plane. When there are several main ultrasonic positioning devices 121, multiple secondary ultrasonic positioning devices 132 are respectively arranged in different planes, and each main ultrasonic positioning device 121 is respectively located at the center of a different plane.

[0040] This application is different from the point-like or flat mapping catheter in the prior art. The unfolded state of the three-dimensional mapping component in this application is set to be spherical. And the ultrasonic positioning devices are divided into main and secondary ones. The secondary ultrasonic positioning device is sheet-shaped and located on the outer surface of the flexible spline. The main ultrasonic positioning device is annular and wrapped around the extension shaft. The secondary ultrasonic positioning device can only measure the tissue distance in one direction, and the number of directions that the main ultrasonic positioning device can measure is the same as the number of secondary ultrasonic positioning devices provided on the flexible spline (for example, if secondary ultrasonic positioning devices are provided on 6 flexible splines, then one main ultrasonic positioning device can measure the tissue distance in 6 directions).

[0041] In one embodiment, as Figure 7 shown, the magnetic positioning component 141 includes a first sensor 1411, a second sensor 1412, and a third sensor 1413. As Figure 8 shown, the magnetic positioning component 141 is used in cooperation with the external positioning plate 2. The external positioning plate 2 is located directly below any part of the patient's upper body. The external positioning plate 2 can be of any shape, and the center of the external positioning plate 2 is the origin of the coordinate system. The direction perpendicular to the positioning plate is the Y-axis, the direction parallel to the hospital bed is the X-axis, and the direction perpendicular to both the X and Y axes and facing the operator is the Z-axis. The magnetic field intensity at each point above the external positioning plate 2 is different. The magnetic positioning component 141 located in the distal cap 14 will measure the magnetic field intensity of the real-time position of the three-dimensional mapping catheter and transmit it to an external device through the insulated electric wire 1411 via the cable interface 153 at the proximal end of the handle 15. The magnetic positioning component 141 is connected to the cable interface 153 provided at the proximal end of the handle 15 through an insulated electric wire. The insulated electric wire passes through the inside of the distal cap 14, the inside of the extension shaft 12, and the inside of the handle 15, and is connected to an external device through the cable interface 153 at the proximal end of the handle 15.

[0042] Further, a knob 151 is provided on the handle 15, and a cable is disposed within the flexible spline 131. The proximal end of the cable passes through the lumen of the flexible tube 11 and is fixedly connected to the knob 151. The knob 151 is used to adjust the length of the cable so as to control the shape of the flexible spline 131. The knob 151 can be disposed at any position on the handle 15. The cable is wound around the knob 151 within the handle 15. When the knob 151 rotates to different angles, the length of the cable is different. By rotating the knob 151 to change the length of the cable, the shape change of the three-dimensional mapping catheter 1 is realized. In one embodiment, a plurality of cables are disposed within each flexible spline 131.

[0043] The above description of the present application is intended to enable those skilled in the art to understand the content of the present invention and implement it, and should not be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims

1. A three-dimensional mapping catheter, comprising a flexible tube (11), an extension shaft (12) disposed within the flexible tube (11) and longitudinally extending along its lumen, a handle (15) disposed at the proximal end of the flexible tube (11), and a distal cap (14) fixedly connected to the distal end of the extension shaft (12), characterized in that: A three-dimensional mapping component (13) is provided at the distal end of the flexible tube (11). The three-dimensional mapping component (13) includes a number of flexible splines (131). The flexible splines (131) are controlled to expand and contract by cables. The distal end of the flexible spline (131) is fixedly connected to the distal cap (14). A number of secondary ultrasonic positioning devices (132) are provided on each flexible spline (131). A primary ultrasonic positioning device (121) is provided on the extension shaft (12). A magnetic positioning component (141) is provided inside the distal cap (14).

2. The three-dimensional mapping catheter according to claim 1, wherein 2 - 64 of the secondary ultrasonic positioning devices (132) are provided on each flexible spline (131). The spacing between the secondary ultrasonic positioning devices (132) on each flexible spline (131) is the same. The distances from the secondary ultrasonic positioning devices (132) at both ends of the flexible spline (131) to the proximal end of the distal cap (14) and the distal end of the flexible tube (11) are also the same.

3. The three-dimensional mapping catheter according to claim 1, wherein The secondary ultrasonic positioning device (132) is in a sheet structure and is located on the outer surface of the flexible spline (131).

4. The three-dimensional mapping catheter according to claim 3, wherein The secondary ultrasonic positioning device (132) includes a secondary ultrasonic buffer and sound-absorbing layer (1321), an outer layer (1322) of the secondary ultrasonic positioning device that wraps the secondary ultrasonic buffer and sound-absorbing layer, a secondary ultrasonic transducer (1323) provided in the secondary ultrasonic buffer and sound-absorbing layer (1321), and a secondary driver (1324) connected to the secondary ultrasonic transducer (1323). The secondary driver (1324) is connected to a cable interface (153) provided at the proximal end of the handle (15) through an insulated electric wire.

5. The three-dimensional mapping catheter according to claim 1, wherein The primary ultrasonic positioning device (121) is fixedly mounted on the extension shaft (12) in a circular shape. The primary ultrasonic positioning device (121) includes a primary ultrasonic buffer and sound-absorbing layer (1211), an outer layer (1212) of the primary ultrasonic positioning device that wraps the primary ultrasonic buffer and sound-absorbing layer, a primary ultrasonic transducer (1213) provided in the primary ultrasonic buffer and sound-absorbing layer (1211), and a primary driver (1214) connected to the primary ultrasonic transducer (1213). The primary driver (1214) is connected to a cable interface (153) provided at the proximal end of the handle (15) through an insulated electric wire.

6. The three-dimensional mapping catheter according to claim 1, wherein When a number of the flexible splines (131) expand into a spherical shape, the primary ultrasonic positioning device (121) and a plurality of the secondary ultrasonic positioning devices (132) are coplanar, and the primary ultrasonic positioning device (121) is located at the center of the plane.

7. The three-dimensional mapping catheter according to claim 6, characterized in that, There are a number of the primary ultrasonic positioning devices (121). A plurality of the secondary ultrasonic positioning devices (132) are respectively provided in different planes. Each primary ultrasonic positioning device (121) is respectively located at the center of a different plane.

8. The three-dimensional mapping catheter according to claim 1, wherein The magnetic positioning component (141) includes a first sensor (1411), a second sensor (1412), and a third sensor (1413). The magnetic positioning component (141) is used in cooperation with an external positioning plate (2).

9. The three-dimensional mapping catheter according to claim 8, wherein The magnetic positioning assembly (141) is connected to a cable interface (153) provided at the proximal end of the handle (15) through an insulated electric wire.

10. The three-dimensional mapping catheter according to claim 1, wherein, A knob (151) is provided on the handle (15). The cable is disposed within the flexible spline (131). The proximal end of the cable is fixedly connected to the knob (151). The knob (151) is used to adjust the length of the cable so as to control the shape of the flexible spline (131).

Images