Lead for pace-making

Abstract

The wire comprises an insulating layer, an electrode tip assembly and an anchoring component, the electrode tip assembly comprises an operating part and an electrode tip, the electrode tip is arranged at the far end of the operating part, and the electrode tip assembly can move between a first position and a second position relative to the insulating layer; the electrode tip assembly at the first position is located in the insulating layer, the electrode tip of the electrode tip assembly at the second position extends out of the insulating layer, the surface of the electrode tip is not smooth, and the area of the minimum cross section of the electrode tip is 4.0 mm < 2 >. According to the lead for pace-making, the electrode tip is provided with the non-smooth surface, so that the electrode tip can be slowly inserted into ventricular septal myocardial tissue even if a conical structure is not adopted, and is easy to screw in. The arrangement can ensure that the cross section is not similar to a conical structure and has a small-area cross section, the cross section is not easy to break when being inserted into heart tissue, and the cross section area is small, so that the damage to normal myocardium when the lead is pulled out is small.

Description

Technical Field

[0001] The present application relates to the technical field of implantable medical devices, and in particular to a lead wire used for pacing in the left bundle branch conduction area of ​​the heart. Background Art

[0002] Implantation of a permanent pacemaker is an effective and mature technical means for treating arrhythmia. Usually, the cardiac pacing wire is implanted into the myocardial tissue at the apex or septum of the right ventricle to pace the local myocardium in the form of electrical pulses. However, clinical practice over the years has found that this traditional right ventricular pacing myocardial method can cause electrical asynchrony between the left and right ventricles, increasing the risk of long-term chronic heart failure or atrial fibrillation in patients. In 2017, scholars first passed the cardiac pacing wire through the ventricular septum of the heart, and directly paced the left bundle branch conduction system under the endocardial surface of the left ventricle (rather than only acting on the myocardial tissue), and took the lead in realizing the physiological left bundle branch area pacing (LBBAP) method. This pacing method can ensure that the electrical pulse directly paces the normal electrical conduction system of the heart, so that the contraction of the left ventricle remains synchronized. It is currently considered to be the most feasible, most promising, and effective physiological pacing method.

[0003] The cardiac pacing lead currently used clinically for LBBAP is the helical active lead (model 3830) produced by Medtronic. Clinical practice shows that its main limitations are: 1) It is difficult to screw the pacing lead into the left bundle branch area deep in the ventricular septum: the lead is relatively soft as a whole, and the overall support force is weak. The myocardial tissue wrapped inside the spiral will prevent the lead from continuing to enter the deep myocardium of the septum. When the outer sheath support force is insufficient or the angle of the septum is not correct, the lead cannot be screwed into the deeper ventricular septum area. 2) Long-term removal is difficult and causes great damage to the myocardium: Since the lead tip is completely screwed deep into the ventricular septum, the design of the head spiral ensures that the lead is secure, but the problem is that the surrounding myocardium and fibrous tissue are repeatedly entangled with the spiral wire, making it extremely difficult to remove this helical active lead implanted in the left bundle branch area. If it is removed violently, the area of ​​damage to the ventricular septum will be large. Summary of the invention

[0004] In order to overcome at least one of the defects of the prior art described above, the purpose of the present application is to provide a pacing wire that is relatively easy to insert into the target tissue, is not easy to break, and causes minimal damage to the myocardium when removed in the long term.

[0005] The present application provides a lead for pacing, comprising: an insulating layer, an electrode head assembly and an anchoring member, wherein the electrode head assembly comprises an operating portion and an electrode head, wherein the electrode head is arranged at the distal end of the operating portion, and the electrode head assembly can move between a first position and a second position relative to the insulating layer, wherein the electrode head assembly in the first position is located within the insulating layer, and the electrode head of the electrode head assembly in the second position extends out of the insulating layer, wherein the electrode head is not a smooth surface, and the minimum cross-sectional area of ​​the electrode head is 4.0 mm 2 .

[0006] Optionally, the electrode tip extends helically around an electrode tip axis, the electrode tip axis extending from proximal to distal.

[0007] Optionally, the electrode head comprises a body, and a first thread is formed on the outer side of the body, or

[0008] A protrusion is formed on the outer side of the body, the protrusion gradually shrinks from the inside to the outside, and the protrusion spirally extends from the proximal end of the body around the outer side surface of the body to the distal end.

[0009] Optionally, the distance that the electrode head in the second position protrudes distally from the insulating layer is greater than the distance that the anchoring member protrudes distally from the insulating layer.

[0010] Optionally, the insulating layer forms an installation channel for installing the electrode head assembly, wherein a second thread is formed at the proximal end of the operating part, and a third thread is formed on the installation channel for threaded connection with the operating part; the electrode head assembly can be moved from the first position to the second position by rotating the operating part relative to the installation channel.

[0011] Optionally, a mounting member is further included, the distal end of which can be engaged with the proximal end of the operating portion, and the operating portion is driven to rotate by rotating the mounting member so that the operating portion is rotated distally into the mounting channel.

[0012] Optionally, the outer diameter of the electrode head is 0.8-1.0 mm, and the outer diameter of the operating part is 3.2 mm.

[0013] Optionally, the operating portion has the same outer diameter as the electrode head, and the operating portion is formed with a non-smooth surface consistent with the electrode head.

[0014] Optionally, the anchoring member is helical in shape.

[0015] Optionally, when the anchoring member is used to fix the pacing lead to the heart tissue, the electrode head assembly can be rotated so that the electrode head assembly moves from the first position to the second position to be inserted into the heart tissue.

[0016] The lead for pacing of the present application sets a non-smooth surface on the electrode head so that the electrode head can be slowly inserted into the heart tissue even without a tapered structure. This setting, on the one hand, can ensure that its cross section will not have a small cross section similar to a tapered structure, and it is not easy to break when inserted into the heart tissue. On the other hand, the electrode head disclosed in the present invention is relatively not sharp, and there is no need to develop a specific delivery sheath to protect the pacing lead before delivering it to the heart tissue. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1-3 A schematic diagram of the structure of a local lead wire for pacing in different states in a certain embodiment is shown.

[0019] Figure 4-6 A schematic diagram of the structure of a local lead wire for pacing in different states in another embodiment is shown.

[0020] Figure 7 It is a schematic diagram of the structure of a lead for pacing in another embodiment of the present disclosure.

[0021] Figure 8 for Figure 7 Enlarged view of part B in .

[0022] Fig. 9 It is a schematic diagram of the partial structure of a lead wire used for pacing in a certain embodiment of the present disclosure.

[0023] Fig.10 for Fig. 9 A magnified view of the local structure.

[0024] Fig.11 This is an electrode head assembly in another embodiment of the present disclosure.

[0025] Fig.12 An electrode head assembly in a certain embodiment of the present disclosure.

[0026] Fig.13It is a schematic diagram of the structure of a lead for pacing in another embodiment of the present disclosure.

[0027] Fig.14 A schematic diagram of the structure of the installation parts.

[0028] Fig.15 for Fig.13 Schematic diagram of the structure of the pacing wire at another angle

[0029] Markings in the figure: 1. Insulating layer; 11. Fixing piece; 2. Electrode head assembly; 21. Operating part; 210. Mounting channel; 211. First mounting channel area; 212. Second mounting channel area; 213. First groove; 214. Second thread; 22. Electrode head; 221. First thread; 222. Main body; 223. Electrode head axis; 23. Proximal end; 3. Anchoring member; 4. Mounting piece; 410. Mounting protrusion. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0031] In the description of the present application, it should be understood that the terms "X-axis", "Y-axis", "Z-axis", "vertical", "parallel", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0032] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] It should be noted that, unlike the traditional pacing method, the LBBAP method is to directly pace the left bundle branch conduction system under the endocardial surface of the left ventricle. This method can ensure that the electrical pulse is excited along the normal conduction system of the heart, so that the contraction of the left ventricle remains synchronized. It is currently considered to be the most feasible, most promising and effective physiological pacing method. When using the left bundle branch area pacing method, the pacing wire needs to be sent into the body through the venous system and reach the right myocardial surface of the ventricular septum. Then let the electrode head continue to move forward and stop after reaching the left bundle branch area. At this time, the electrode head needs to move about 10mm in the myocardial tissue to reach the left bundle branch area. For most pacing wires, the user needs to apply force from the proximal end of the pacing wire to push the electrode head at the distal end of the pacing wire to move, and the length of the pacing wire is about 52-58cm, so the difficulty of operation is not low. It is very likely that in the process of pushing the electrode head to move, the electrode head will be inserted into the wrong position or damaged. In order to solve the problem of electrode tip being damaged, the common practice is to make the diameter of the electrode tip larger to strengthen the electrode tip, but the above method will cause greater damage to the human body.

[0034] In view of the above problems, the present disclosure provides a lead for pacing, such as Figure 1-6 As shown, the wire includes: an insulating layer 1, an electrode head assembly 2 and an anchoring member 3. The electrode head assembly 2 includes an operating portion 21 and an electrode head 22. The electrode head assembly 2 can move between a first position and a second position relative to the insulating layer 1. The electrode head assembly 2 in the first position is located inside the insulating layer 1. The electrode head assembly 2 in the second position has the electrode head 22 extending outside the insulating layer 1. The electrode head 22 is not a smooth surface, and the minimum cross-sectional area of ​​the electrode head 22 is 4.0 mm 2 .

[0035] In some optional embodiments, such as Figure 7 and Figure 8As shown, the electrode head 22 is not a smooth surface, which means that the electrode head 22 includes a body 222, and a first thread 221 is formed on the outer side of the body 222, or more specifically, a protrusion is formed on the outer side of the body 222, the protrusion gradually decreases from the inside to the outside, and the protrusion spirally extends from the proximal end of the electrode head 22 to the distal end around the outer side of the electrode head 22. More specifically, the body 222 of the electrode head 22 is a columnar structure, and the first thread 221 or the above-mentioned protrusion is arranged on the outside for cutting. The advantage of this arrangement is that when the distal end of the electrode head 22 contacts the myocardial tissue, the rotating electrode head 22 can cut the myocardial tissue through the first thread 221 or the protrusion on the electrode head 22, so that the electrode head 22 can be smoothly inserted into the myocardial tissue. Moreover, when the electrode head 22 is inserted into the myocardial tissue, it is inserted into the myocardial tissue by rotating circumferential cutting, and it does not need to be set as a conical head, which reduces the cross-sectional area of ​​the electrode head 22, and is not easy to be damaged during the insertion process and remain in the myocardial tissue.

[0036] For ease of understanding, Figure 1-7 A first direction A is marked in FIG. 1 , and the first direction A extends from the proximal end to the distal end of the lead for pacing. The cross section is a cross section perpendicular to the first direction A.

[0037] and Figure 8 Different from the structure shown in FIG. 1 , in some optional embodiments, the electrode tip 22 extends helically around an electrode tip axis 223, and the electrode tip axis 223 extends from the proximal end to the distal end. More specifically, as shown in FIG. Fig. 9 and Fig.10 As shown, the electrode head axis 223 is located on the central axis of the insulating layer and extends in the direction from the proximal end to the distal end, wherein the middle portion of the electrode head 22 may be hollow. Therefore, the electrode head is formed by spirally extending around the central axis of the insulating layer. In this embodiment, since the electrode head 22 itself no longer requires a columnar body, the outer diameter of the spiral electrode head 22 (i.e., the distance between the two outer edge points where a straight line passing through the center of the electrode head intersects the electrode head on the cross section) can be smaller, and the cross-sectional area of ​​the electrode head 22 is smaller, resulting in less damage to the body. It should be noted that the cross section of the electrode head mentioned above is perpendicular to the electrode head axis 223. In addition, as Fig.10 As shown, the electrode head 22 gradually shrinks from the inside to the outside. The inside of the electrode head 22 refers to the side facing the electrode head axis 223, and the outside of the electrode head 22 refers to the side facing away from the electrode head axis 223. It should be noted that, for the convenience of drawing, the electrode head axis 223 is fully exposed outside the electrode head 22, but in fact the electrode head axis 223 is located inside the electrode head 22, specifically at the most central position. The electrode head axis 223 may be a virtual axis. In addition, it is not ruled out that in some embodiments, the electrode head axis 223 is an actual linear object.

[0038] Optionally, the distance that the electrode head 22 in the second position extends far from the insulating layer 1 is greater than the distance that the anchoring member 3 extends far from the insulating layer 1. It should be noted that the anchoring member 3 is mainly used to preliminarily fix the pacing lead of the present disclosure in the myocardial tissue. The electrode head 22 needs to extend into the left bundle branch area inside the myocardial tissue to perform pacing in the left bundle branch area. Therefore, the anchoring member 3 does not need to be inserted deeply into the myocardial tissue to avoid causing greater damage to the myocardial tissue. Specifically, the electrode head 22 extends about 10 mm far away.

[0039] Since the pacing lead of the present invention adopts a cylindrical electrode head 22 with a cutting protrusion on the side or a spiral electrode head, it mainly relies on the cutting force brought by rotation to be inserted into the myocardial tissue, so the outer diameter of the electrode head 22 of the present invention can be set smaller and will not easily break. Specifically, the outer diameter of the electrode head 22 of the present invention is 0.8-1.0mm. In addition, the outer diameter of the operating part 21 is 3.2mm.

[0040] Specifically, see Figure 1 Under normal circumstances, the electrode head 22 is located in the insulating layer 1, that is, in the first position. After the rotation, the electrode head 22 can be rotated forward to be inserted into the myocardial tissue. At this time, since the anchoring member 3 is first fixed in the myocardial tissue, the electrode head 22 is not easy to deviate when it is rotated and inserted into the myocardial tissue. Figure 2 It is a schematic diagram of the structure of a local lead wire for pacing when the electrode head 22 rotates and moves toward the distal end. At this time, the electrode head 22 has extended out of the insulating layer 1, but has not reached the end point and can still move toward the distal end. Figure 3 It is a schematic diagram of the structure of the local lead wire used for pacing when the electrode head 22 reaches the end point. At this time, the electrode head 22 has reached the second position.

[0041] Optionally, the insulating layer 1 is formed with a mounting channel 210 for mounting the electrode head assembly 2. Fig.11As shown, the proximal end of the operating portion 21 is formed with a second thread. The mounting channel 210 is formed with a third thread to be threadedly connected with the operating portion 21. First, the mounting channel 210 has a certain guiding function for guiding the movement of the electrode head assembly 2. Secondly, since the operating portion 21 is threadedly connected with the mounting channel 210, the movement mode of the operating portion 21 and the electrode head 22 in the mounting channel 210 is limited. More specifically, it is necessary to continuously rotate the operating portion 21 to screw the operating portion 21 into the mounting channel 210 far away, and then the electrode head 22 located at the far end of the operating portion 21 can move far away. This ensures that the movement mode of the electrode head 22 is to rotate and move far away, avoiding the electrode head 22 being directly moved forward by force, resulting in damage to the electrode head 22. More specifically, the user can rotate the operating portion 21 relative to the mounting channel 210 to allow the entire electrode head assembly 2 to move in the distal direction, so the electrode head assembly 2 can move from the first position to the second position, so that the electrode head 22 extends out of the insulating layer 1. At the same time, the operating portion 21 can be rotated in the opposite direction relative to the installation channel 210 to move the entire electrode head assembly 2 in the proximal direction, so that the electrode head assembly 2 can move from the second position to the first position, so that the electrode head 22 is retracted into the insulating layer 1 again.

[0042] In addition, since the installation channel is formed with a third thread to be threadedly connected with the operating portion 21

[0043] In some optional embodiments, such as Fig.12 As shown, the operating portion 21 of the electrode head assembly 2 has the same outer diameter as the electrode head 22, and the operating portion 21 is formed with a non-smooth surface consistent with the electrode head 22. It should be noted that, for the convenience of preparation, under normal circumstances, the operating portion 21 and the electrode head 22 are integrally formed. For example, when the electrode head 22 is a cylindrical body and a first thread is formed on the outside of the body, then the operating portion 21 will also be a cylindrical structure with a thread formed on the outside. When the electrode head is a spiral structure, the operating portion will also be a spiral structure. It should be noted that for Fig.12 The electrode head assembly 2 shown can be regarded as the electrode head 22 when the electrode head assembly 2 is in the second position, and the part located in the insulating layer 1 is regarded as the operating part 21. The outer diameter of the electrode head 22 and the operating part in the electrode head assembly 2 is 0.8-1.0 mm.

[0044] In addition, in some optional embodiments, since the outer diameter of the electrode head 22 is small, if the outer diameter of the entire electrode head assembly 2 is consistent with it, the operation difficulty is extremely great. In some embodiments, the outer diameter of the operating portion 21 is large, and the user can hold the operating portion 21 with a larger cross-sectional area to rotate, thereby driving the electrode head 22 to rotate. Optionally, the outer diameter of the electrode head is 0.8-1.0 mm, and the outer diameter of the operating portion is 3.2 mm.

[0045] More specifically, for an electrode tip assembly having different outer diameters of the electrode tip and the operating portion, such as Figure 4-5 As shown, the mounting channel 210 optionally includes a first mounting channel area 211 and a second mounting channel area 212 which are connected sequentially from far to near. The first mounting channel area 211 is used to mount the electrode head 22, and the second mounting channel area 212 is used to mount the operating portion 21. The inner diameter of the first mounting channel area 211 is substantially the same as the diameter of the electrode head 22, and the inner diameter of the second mounting channel area 212 is substantially the same as the operating portion 21. Therefore, when the electrode head assembly 2 continues to rotate forward to a certain distance, the operating portion 21 cannot be inserted into the first mounting channel area 211, thereby limiting the electrode head assembly 2 from continuing to move forward.

[0046] In addition, for an electrode tip assembly having the same outer diameter as the operating portion, such as Figure 1-3 As shown, the installation channel 210 may be a channel extending from the proximal end to the distal end and having a consistent inner diameter. Specifically, a thread or a spiral channel may be formed in the installation channel 210 so that the electrode head assembly 2 can only move forward or backward toward the distal end by rotating, so as to ensure that the electrode head assembly 2 does not move forward or backward directly, thereby reducing the possibility of damage to the electrode head.

[0047] Optional, such as Figure 13-15 As shown, the lead for pacing also includes a mounting member 4, the distal end of which can be engaged with the proximal end of the operating part 21, and the operating part 21 is rotated by rotating the mounting member 4 to drive the operating part 21 to rotate so that the operating part 21 is screwed into the installation channel in the far direction. Specifically, a first groove 213 is formed at the proximal end of the operating part 21, and a mounting protrusion 410 is provided at the distal end of the mounting member 4. The first groove 213 matches the shape of the mounting protrusion 410, and the mounting member 4 and the operating part 21 are installed together through the mounting protrusion 410 and the first groove 213. The user can rotate the mounting member 4 to drive the operating part 21 to rotate. Among them, the cross-section of the mounting protrusion 410 can be rectangular, pentagonal, triangular, etc., and it does not need to be circular. Specifically, a second groove is provided on the side wall of the mounting member 4 to install a sealing ring, and the mounting member 4 is sealed and fitted with the installation channel through the sealing ring to install and fix the mounting member 4.

[0048] And for Fig.12 As for the electrode head assembly 2 shown, a proximal end thereof may be formed with a proximal portion 23 , and the proximal portion 23 is formed with a groove to be snap-fitted with the mounting protrusion 410 of the mounting member 4 .

[0049] In some embodiments, the insulating layer 1 is formed with a first cathode interface, a second cathode interface, a first anode interface, and a second anode interface, wherein the first cathode interface and the second cathode interface are connected through a cathode conductive coil located inside the insulating layer 1. The first anode interface and the second anode interface are connected through an anode conductive coil located inside the insulating layer 1. It should be noted that after the electrode head 22 of the wire is inserted into the left bundle branch region in the myocardium, the proximal end of the wire is connected to the pulse generator. At this time, the pulse generator will contact and connect the first cathode interface and the first anode interface located at the proximal end respectively. When the electrode head 22 moves to the distal end and contacts the left bundle branch region, the electrode head 22 will contact the second cathode interface located at the distal end of the insulating layer 1. At the same time, since the second anode interface is located outside the wire, the blood outside the wire will connect the second cathode interface with the second anode interface, so that the left bundle branch region and the pulse generator form a loop, thereby allowing the pulse generator to emit discharge pulses to the left bundle branch region. In addition, the pacing coil is composed of an anode conductive coil and a cathode conductive coil, and is specifically formed by winding multiple strands of steel wire or copper wire into a hollow coil shape, which is conductive and ensures that the pulse generator current reaches the electrode head 22 through the coil to perform the pacing function.

[0050] It should be noted that the electrode head 22 can be energized in various ways, not limited to the conventional energization methods mentioned above. In addition, the energization position of the electrode head 22 is not limited to the left bundle branch area, and it can perform electric shocks on other areas in the myocardium according to different situations.

[0051] In addition, in order to facilitate installation, a fixing member 11 is provided on the outside of the proximal end of the guide wire to connect with the pulse generator.

[0052] Optionally, the electrode head 22 is made of nickel alloy, and the anchoring member 3 is made of titanium nitride-plated platinum alloy.

[0053] In some embodiments, when the anchoring member 3 is used to fix the lead for pacing to the cardiac tissue, the electrode head assembly 2 can be rotated so that the electrode head assembly 2 moves from the first position to the second position to be inserted into the cardiac tissue. As described above, in some embodiments, the operating portion 21 of the electrode head assembly 2 is threadedly connected to the mounting channel, so that the user can rotate the rotating electrode head assembly 2 to rotate it forward to the far side, thereby moving it from the first position to the second position, so that the electrode head 22 leaks out of the insulating layer 1.

[0054] It should be noted that the end close to the lead user is the proximal end, and the end far from the lead user (ie, close to the heart) is the distal end.

[0055] When in use, first, the wire for pacing disclosed in the present invention is delivered into the body through the venous system. Specifically, the distal end of the wire reaches the right myocardial surface of the ventricular septum under the guidance of the 9Fr inner diameter sheath. First, the wire operating part 21 is rotated, and the spiral anchoring member 3 at its distal end can be embedded in the myocardium for preliminary anchoring. Then, the proximal end of the electrode head assembly 2 is inserted using the mounting member 4, and the electrode head assembly 2 and the insulating layer 1 are rotated at a uniform speed, so that the electrode head assembly 2 and the insulating layer 1 rotate relative to each other, and then the electrode head assembly 2 is spirally moved to the distal end and gradually rotated out to the deep part of the ventricular septum, and stopped after reaching the left bundle branch area.

[0056] Optionally, the insulating layer 1 has a length of 60 cm and an inner diameter of 2.4 mm. The insulating layer 1 is made of insulating materials with good biocompatibility and blood compatibility, such as polylactic acid, polyurethane, etc., to ensure the electrical insulation of the entire wire and to be safely applicable to the human body.

[0057] In addition, the spiral distribution density of the anchoring member 3 is low, while the distribution density of the first thread 221 of the electrode head 22 is large or the spiral density of the electrode head 22 is high. Specifically, the pitch of the first thread 221 of the electrode head 22 (or the pitch of the spiral of the electrode head) is greater than the pitch of the anchoring member 3. The pitch refers to the distance between two adjacent spiral peaks in the same direction on the spiral line.

[0058] Moreover, the anchoring member 3 and the electrode head 22 are coated with dexamethasone acetate, which helps to lower the pacing threshold between the wire and the contacting myocardium and reduce the amplitude of the threshold variation. The combination of the above different materials ensures that the entire pacing wire has moderate hardness, certain supporting strength and flexibility, and a smooth surface with low friction.

[0059] The lead for pacing disclosed in the present invention is applied to LBBAP and has the following advantages: (1): It is easy to enter the left bundle branch area deep in the ventricular septum and is easy to operate. Specifically, when the lead is twisted at the proximal end, the tight thread 221 structure on the electrode head 22 can effectively provide radial cutting force to screw into the deep part of the ventricular septum; (2) Long-term pacing is stable and not easy to dislocate, and the lead contacting the ventricular septal myocardium and the tight thread 221 design entering the septal myocardial tissue are not easy to break: the material selected for the entire pacing lead ensures that it has moderate hardness, certain support and flexibility, and the surface of the insulating layer 1 is smooth and has low friction. The spiral anchoring member 3 at the distal end of the lead plus the electrode head assembly 2 with external thread 221 can ensure stability and will not shift due to the spontaneous contraction and relaxation of the heart; (3) It is easy to remove in the long term and causes little damage to the myocardium. Specifically, the distal end of the lead can be screwed into the deep part of the myocardial tissue through the outer thread 221 of the head electrode, so the diameter is small and can be directly pulled out. After extraction, the contraction of the ventricular septum myocardium itself will drive the closure of the extraction hole, so the damage is relatively small. The outer spiral anchoring member 3 only enters the superficial part of the right side of the ventricular septum, which will only damage the local myocardium on the right surface. The hemodynamics of the right ventricle is slower than that of the left ventricle, and the inflammatory response caused by venous blood generally does not cause serious embolic events; (4) Compatible with all types of pulse generators currently available on the market: This design connects the pulse generator end at the proximal end of the wire, and the original interface design can be retained. Therefore, it can be directly applied to existing pulse generator types without the need to develop a new matching pulse generator wire interface.

[0060] It should be understood that what is described in the above drawings and specific embodiments are merely exemplary embodiments of the present application, and are not exhaustive of the possible implementation methods of the present application. Those skilled in the art may make various changes to the above specific implementation methods within the scope of protection of the present application without departing from the main purpose of the present application.

Claims

1. A lead for pacing, comprising: An insulating layer, an electrode head assembly and an anchoring member, characterized in that the electrode head assembly includes an operating portion and an electrode head, the electrode head is arranged at the distal end of the operating portion, the electrode head assembly can move between a first position and a second position relative to the insulating layer, the electrode head assembly in the first position is located in the insulating layer; the electrode head of the electrode head assembly in the second position extends out of the insulating layer, the electrode head is not a smooth surface, and the minimum cross-sectional area of ​​the electrode head is 4.0 mm 2 .

2. The pacing lead according to claim 1, characterized in that: The electrode tip extends helically about an electrode tip axis extending from proximal to distal.

3. The pacing lead according to claim 1, characterized in that: The electrode head comprises a body, and a first thread is formed on the outer side of the body, or A protrusion is formed on the outer side of the body, the protrusion gradually shrinks from the inside to the outside, and the protrusion spirally extends from the proximal end of the body around the outer side surface of the body to the distal end.

4. The pacing lead according to claim 1, characterized in that: The distance that the electrode head in the second position protrudes distally from the insulating layer is greater than the distance that the anchoring member protrudes distally from the insulating layer.

5. The pacing lead according to claim 1, characterized in that: The insulating layer forms an installation channel for installing the electrode head assembly, wherein a second thread is formed at the proximal end of the operating part, and the installation channel forms a third thread for threaded connection with the operating part; the electrode head assembly can be moved from the first position to the second position by allowing the operating part to rotate relative to the installation channel.

6. The lead for pacing according to claim 5, characterized in that: It also includes a mounting member, the distal end of which can be engaged with the proximal end of the operating portion, and the operating portion can be rotated by rotating the mounting member to rotate the operating portion so that the operating portion is rotated distally into the mounting channel.

7. The lead for pacing according to claim 1, characterized in that: The outer diameter of the electrode head is 0.8-1.0 mm, and the outer diameter of the operating part is 3.2 mm.

8. The lead for pacing according to claim 1, characterized in that: The operating portion has the same outer diameter as the electrode head, and the operating portion is formed with a non-smooth surface consistent with the electrode head.

9. The lead for pacing according to claim 1, characterized in that: The anchoring member is helical in shape.

10. The lead for pacing according to any one of claims 1 to 9, characterized in that: When the anchoring member is used to fix the lead for pacing to the heart tissue, the electrode head assembly can be rotated so that the electrode head assembly moves from the first position to the second position to be inserted into the heart tissue.

Images