Implantable medical lead assembly with loop section

Abstract

The invention generally relates to an implantable medical lead assembly (100), an implantable cardiac device comprising such a medical lead assembly and a process for generating an implantable medical lead assembly.

Description

[0001] Applicant: BIOTRONIK SE & Co. KG

[0002] Date: 05.11.2025

[0003] Our Reference: 24.122P-WO

[0004] Implantable medical lead assembly with loop section

[0005] The invention generally relates to an implantable medical lead assembly, an implantable cardiac electronic device comprising such a medical lead assembly and a process for generating an implantable medical lead assembly.

[0006] Medical leads implanted in a patient’s body for electrical cardioversion, pacing or defibrillation of the heart are generally known in the art. In particular, electrically transmissive leads may be implanted in or about the heart to reverse (i.e., defibrillate or cardiovert) certain life-threatening arrhythmias or to stimulate contraction (pacing) of the heart. Electrical energy is transmitted from a pulse generator which is electrically connected to the lead. Such transmitted electrical energy is applied to the heart via the lead to return the heart to normal rhythm or to stimulate the heart. Leads have also been used to sense conditions, materials or events (generally referred to as "sense" or "sensing") in the body, such as electrical potential in the atrium or ventricle of the heart. For that such medical lead may be connected to a sensing device using a connector assembly at the proximal end of the medical lead. Alternatively, the sensed signals may be transmitted to and processed by the pulse generator, and, for example, used for pacing control.

[0007] Medical leads represent the electrical link between the pulse generator and the patient’ s body tissue which is to be treated or sensed. Accordingly, the medical lead must be reliably mechanically and electrically connected to the patient’s body tissue at a pre-defined target location.

[0008] A medical lead assembly for substernal implantation is also described in US 2016 / 0175580 Al. The document discloses a lead system intended for placement in the substernal space, aiming to reduce complications associated with transvenous implantation. Most of the known pacemakers and defibrillators are implanted as transvenous systems. For example, defibrillators are mostly implanted in the left upper chest area, from where one or more leads are then guided through veins to the heart. However, such transvenous systems can cause complications such as venous thrombosis or injury.

[0009] As an alternative to transvenous systems, sub sternal systems can be applied, particularly in the treatment of potentially life-threatening arrhythmias such as ventricular tachycardia and ventricular fibrillation. The term “substemal systems” refers to the placement of a defibrillator in which the lead is not inserted into the heart transvenously (via a vein) as usual, but is instead placed substernally, i.e. below the breastbone (sternum).

[0010] In substernal defibrillation, a lead is inserted under the sternum during a minimally invasive operation. This lead lies directly on the epicardium (the outer layer of the heart), but outside the heart and the great vessels. Placement under the sternum enables direct but extracardiac (outside the heart) stimulation.

[0011] However, known leads for the substemal implantation technique has the disadvantage that injuries can be caused by the "tip" of the lead when the lead body is advanced, which can lead to more or less critical complications (haemorrhages, perforation of the lungs, thymus perforation in young patients, etc.). Furthermore, the lead body must be very flexible in the distal area in order to avoid traumatic injuries caused by the lead tip after implantation. This flexibility can have a negative effect on the positional stability of the electrode.

[0012] Against this background, it is an objective of the present invention to enable implanting a substernal lead without injury and fixing it securely and atraumatic.

[0013] The above-mentioned disadvantages are overcome by an implantable medical lead assembly having the features of claim 1, by an implantable cardiac electronic device having the features of claim 11 and a method for providing an implantable medical lead having the features of claim 14.

[0014] According to an embodiment of the present invention, an implantable medical lead assembly is provided, wherein the implantable medical lead assembly comprises a cable-shaped lead body, wherein the lead body comprises at least one cable section that is electrically insulated

[0015] 24.122P-WO / 05.11.2025 from the outside and at least a first pole section, wherein the first pole section is configured in such a way that electrical currents can be transmitted to human tissue via the first pole section. The implantable medical lead assembly comprises a connecting means, wherein the connecting means and the lead body are configured in such a way that the lead body can be brought into a first configuration or is in the first configuration, wherein in the first configuration of the lead body, the lead body alone or together with the connecting means forms a closed loop defining a loop opening and a loop section of the lead body, such that the loop section circumferentially surrounds the loop opening (at least partially). Such a lead assembly facilitates an atraumatic placement of the lead body below the sternum since the lead body does not have an edgy lead tip. Furthermore, the loop enables an operator to place the pole sections with a high position stability due to the loop shape and the high friction associated with the loop shape.

[0016] In another embodiment of the present invention, in the first configuration of the lead body, the loop section comprises at least the first pole section, preferably at least the first poles section and the cable section partially or completely. Consequently, the first pole section can be placed above the heart with a high precision and position stability.

[0017] In another embodiment of the present invention, the connecting means can be mounted so as to be movable relative to a region of the lead body in such a way that the loop section can be enlarged or reduced by a movement of the lead body. This enables the operator to insert the lead assembly into a human body when the loop section is very small and is not an obstacle for inserting. After insertion, the operator can enlarge the loop by simply pushing the lead body forward to properly position the pole sections without pushing an edgy distal lead tip into the human body.

[0018] In another embodiment of the present invention, the connecting means comprises a connecting element, e.g. a clipping device, that is firmly connected to a first mounting section of the lead body and movable connected to a second mounting section proximal located to the first mounting section. This facilitates an easy way to enlarge the loop section by pushing the lead body or to minimize the loop section my pulling the lead body. For example, the connecting element can be firmly fixed to a distal end section of the lead body and movable connected to a mounting section proximal to the distal end section.

[0019] 24.122P-WO / 05.11.2025 In another embodiment of the present invention, the connecting means comprises a connecting element, e.g. a material bond, that is firmly connected to a first mounting section of the lead body and firmly connected to a second mounting section proximal located to the first mounting section. For example, adhesive or ultrasonic bonding can be used to connect the first mounting section to the second mounting section.

[0020] In another embodiment of the present invention, the connecting means comprises a connecting device, e.g. a sleeve or a catheter section, that is movable connected to a first mounting section of the lead body and movable connected to a second mounting section proximal located to the first mounting section.

[0021] In another embodiment of the present invention, the connecting means comprises an eyelet with a through-opening or a clipping device with an open recess, wherein the eyelet or the clipping device is configured such that a region of the lead body can be or is located within the through-opening or the open recess. Such an eyelet is fairly simple to use - especially for the operator when lead assembly has to be prepared directly before implantation. However, the eyelet connection can also be effectively created during production of the lead assembly, such that the lead assembly leaves the production unit already with a loop section creating a closed loop.

[0022] In another embodiment of the present invention, the lead body comprises an inner lumen, wherein the inner lumen extends in the longitudinal direction of the lead body and is configured such that a mandrin can be inserted into the inner lumen. Herewith, an operator can implant the lead assembly more controlled.

[0023] In another embodiment of the present invention, the lead body is pre-bent two-dimensionally or three-dimensionally, wherein preferably in a section which, in the first configuration of the lead body, is part of the loop section, the lead body is pre-bent two-dimensionally or three-dimensionally. Herewith, the loop section has a larger position stability inside the human body after implantation.

[0024] In another embodiment of the present invention, the medical lead assembly comprises a second electrically conductive pole section, wherein the first pole section and the second pole section are spatially separated from each other by the cable section. For example, the

[0025] 24.122P-WO / 05.11.2025 first pole section can be used as a shock electrode for defibrillation and the second pole section can be used as a heart stimulating electrode for pacing. Particularly, the second pole section can have a length smaller than the length of the first pole section.

[0026] According to an embodiment of the present invention, the medical lead assembly is configured in such a way that the length of the loop section can be varied between 4 cm and 30 cm, in particular between 8 and 20 cm.

[0027] According to an embodiment of the present invention, the lead body has a flexural rigidity of at least 60 N / mm2and at most 240 N / mm2, in particular of at least 150 N / mm2and at most 240 N / mm2in a lead body section that can potentially represent the largest possible loop section.

[0028] According to an embodiment of the present invention, the connecting means comprises a connecting element such as a sleeve, wherein the connecting element is firmly connected to a distal end section of the lead body.

[0029] The underlying technical problem is also solved by an implantable cardiac electronic device comprising an implantable medical lead assembly according to one of the aforementioned embodiments, wherein the implantable medical lead assembly is configured to be transplanted substernal. In this sense the medical lead assembly has a size and shape such that is transplantable below the sternum.

[0030] In another embodiment of the present invention, the implantable cardiac electronic device is configured in a way that the first pole section is a shock electrode for defibrillation or a heart stimulation electrode for pacing. Especially the usage as a defibrillator is expected to be highly advantageous.

[0031] In another embodiment of the present invention, the implantable cardiac electronic device is configured in a way that the first pole section is a shock electrode for defibrillation and the second pole section is a heart stimulation electrode for pacing. In this way, the device fulfills both the role of a defibrillator as well as the role of a pacemaker.

[0032] 24.122P-WO / 05.11.2025 The underlying technical problem is also solved by a method for providing an implantable medical lead assembly with a loop section of a lead body, comprising the steps: (A) Providing a lead body with a connecting means at a distal end section of the lead body; (B) Firmly or flexibly connecting the distal end section to a middle section of the lead body proximal to the distal end section via the connecting means, such that the lead body and the connecting means together form a closed loop.

[0033] In another embodiment of the present invention, step A) comprises the following steps: (Al) providing a connecting means with a connecting element, (A2) Firmly fixing the connecting element to a distal end section of the lead body.

[0034] The present invention will now be described in further detail with reference to the accompanying schematic drawing, wherein

[0035] Fig. 1 shows an embodiment of the implantable lead assembly,

[0036] Fig. 2a shows a human rib cage together with the embodiment of Figure 1, wherein the implantable lead body is in a starting configuration with a small loop section,

[0037] Fig. 2b shows as Figure 2a the human rib cage together with the embodiment of Figure 1, wherein the implantable lead body is in an intermediate configuration with a loop section length larger than for the configuration shown in Figure 2a,

[0038] Fig. 2c shows as Figure 2a the human rib cage together with the embodiment of Figure 1, wherein the implantable lead body is in a final configuration with a loop section length larger than for the configuration shown in Figure 2b,

[0039] Fig. 3a shows an embodiment of the implantable lead assembly together with a catheter, wherein the lead body is in a starting configuration,

[0040] Fig. 3b shows the embodiment and the catheter of Figure 3a, wherein the lead body is in an intermediate configuration,

[0041] 24.122P-WO / 05.11.2025 Fig. 3c shows the embodiment and the catheter of Figure 3a, wherein the lead body is in a final configuration.

[0042] The embodiment of the implantable medical lead assembly 100 shown in Figure 1 comprises a lead body 105 and a connecting means 120. The lead body 105 together with the connecting means 120 forms a closed loop defining a loop opening 115. In this case, the connecting means 120 comprises a wire 121 and a sleeve 122 such that the wire 121 is fixed to the distal end section 125 of the lead body 105 via the sleeve 122. The sleeve 122 is put over the distal end section 125 and is connected to the wire 121 via a material bond or frictional connection. For example, the sleeve 122 can be a shrink tubing facilitating a strong frictional connection between lead body 105 and wire 121.

[0043] The embodiment shown in Figure 1 comprises two pole sections 130 and 140, namely a first distal pole section 130 adjacent to the distal end section 125 of the lead body 105 and a second pole section 140 proximal to the first pole section 130. Between these pole sections 130 and 140, there is a cable section 110 separating both pole section 130 and 140 from each other. Preferably, the wire 121 and the sleeve 122 of the connecting means 120 are electrically isolating such that the risk of electrical shorts between two pole sections 130 and 140 of the lead body 105 - as shown here - is very low.

[0044] The shown medical lead assembly 100 can be used as part of an implantable cardiac electronic device such an implantable defibrillator. In case of a defibrillator, the first pole section 130 can be used as a shock electrode for defibrillation and the second pole section 140 can be used as a heart stimulating electrode. Thus, the first pole section 130 - the shock electrode - is responsible for delivering a strong electrical impulse (shock) to terminate lifethreatening cardiac arrhythmias such as ventricular fibrillation or ventricular tachycardia. The shock depolarises the heart tissue almost completely in order to restart the heart and bring it back into a normal rhythm. The second pole section 140 - the stimulation electrode - is used to stimulate the heart with small, regular electrical impulses to maintain a stable heart rate, especially for bradycardias (abnormally slow heart rate). These electrode helpa regulate the heart rhythm.

[0045] 24.122P-WO / 05.11.2025 For such purposes, the lead body 105 has to be placed correctly in the substemal region, which is the region below the sternum 205 of the rib cage 200. Figures 2a, 2b and 2c illustrate how the lead body 105 can be implemented accordingly by showing the lead body 105 together with the rib cage 200 with the sternum 205. Although the lead body 105 is shown here in the forefront of the rib cage 200 for illustrative reasons, Figures 2a, 2b and 2c has to be understood as showing the lead body 105 below the rib cage 200 and the sternum 205. In the shown case, the middle section of the lead body 105 is flexible connected to the connecting means 120 such that the loop section can be enlarged by pushing the lead body 105 in a distal direction or can be downsized by pulling the lead body 105 in a proximal direction.

[0046] Since the lead body 105 comprises a loop section, the lead body 105 does not possess any tip effectively. This tip-less shape allows the lead body 105 to be moved safely through the sub-sternal fat tissue without a high risk of trauma.

[0047] Figure 2a shows the leady body 105 in a starting configuration in which the loop section has a comparable small length. This configuration is used to insert the lead body 105 into a human body in course of a small medical operation. Consequently, only a small incision is necessary for implanting such that the whole implanting procedure can be performed minimal invasive. After inserting the minimal loop section of the lead body 105, the loop section is enlarged by pushing the lead body 105 forward in a distal direction.

[0048] Figure 2b shows an intermediate configuration of the lead body 105 in which the loop section is already enlarged but the pole sections 130 and 140 are still not located at their target locations. As an example, the lead body 105 can possess an inner lumen such that a mandrin can be inserted into the lumen enhancing the stiffness of the leady body 105 temporarily as long as the mandarin is inserted. This technique can be used during lead implantation to facilitate advancement of the lead body 105 and accurate placement of the pole sections 130 and 140.

[0049] Finally, Figure 2c shows the final configuration of the leady body 105. Both pole sections 130 and 140 are placed substernal such that the first pole section 130 can be used as a shock electrode and the second pole section 140 can be used as a heart stimulating electrode.

[0050] 24.122P-WO / 05.11.2025 Figures 3a, 3b and 3c show a starting configuration (Figure 3a) of the lead body 105, an intermediate configuration (Figure 3b) of the lead body 105 and a final configuration (Figure 3c) of the lead body 105 in close-up. Further, in this case, the lead body 105 is initially placed inside a catheter 300. The catheter 300 can be used to insert the lead body 105 into the human body. Using the catheter 300 simplifies the implantation such that the whole procedure is minimal invasive. Indeed, Figure 3a shows a starting configuration in which the loop section is such small and compressed by the catheter 300 that the lead body’s width - measured perpendicular to the longitudinal axis of the catheter 300 - is essentially equal to the associated catheter width.

[0051] With respect to the embodiment of a lead assembly 100 shown in Figures 3a, 3b and 3c, the connecting means 120 can be designed in two ways particularly. According to a first example, the upper catheter section 123 represents the entire connecting means 120, which temporarily connects two mounting sections of the lead body 105 by simply pushing them together inside the catheter 300. Once the lead body 105 is correctly positioned and the entire catheter 300 is removed, the loop section is no longer closed. Nevertheless, the lead body 105 can be firmly placed within the human tissue due to the high friction of the lead body 105 caused by the loop shape, even though the loop is not closed at the distal end section 125 of the lead body 105. According to a second example, the connecting means 120 comprises the upper catheter section 123 that temporarily holds together two mounting sections of the lead body 105 and a firm and permanent connection between two other mounting sections of the lead body 105 that are still inside the catheter 300 when looking at Figures 3a, 3b and 3c. In other words, this firm and permanent connection already creates a potential closed loop section before the lead body 105 is inserted into the catheter 300, the potential loop section having a fixed and non-changeable length. Thus, when the lead assembly 100 is placed and the catheter 300 is removed, the loop portion of the lead body 105 remains a closed loop due to this firm and permanent connection. In this case, the catheter 300 is used to minimise the potential loop section for insertion of the lead assembly 100 into the human body.

[0052] 24.122P-WO / 05.11.2025 Further, the meaning of the reference signs is listed below:

[0053] 100 Lead assembly

[0054] 105 Lead body

[0055] 110 Cable section

[0056] 115 Loop opening

[0057] 120 Connecting means

[0058] 121 Wire

[0059] 122 Sleeve

[0060] 123 Upper catheter section

[0061] 125 Distal end section

[0062] 130 First pole section

[0063] 140 Second pole section

[0064] 200 Rib cage

[0065] 205 Sternum

[0066] 300 Catheter

[0067] 24.122P-WO / 05.11.2025

Claims

Claims1. An implantable medical lead assembly (100),wherein the implantable medical lead assembly (100) comprises a cable-shaped lead body (105),wherein the lead body (105) comprises at least a first cable section (110) that is electrically insulated from the outside and at least a first pole section (130), wherein the first pole section (130) is configured in such a way that electrical currents can be transmitted to human tissue via the first pole section (130), characterized in thatthe implantable medical lead assembly (100) comprises a connecting means (120), wherein the connecting means (120) and the lead body (105) are configured in such a way that the lead body (105) can be brought into a first configuration or is in the first configuration,wherein in the first configuration of the lead body (105), the lead body (105) alone or together with the connecting means (120) forms a closed loop defining a loop opening (115) and a loop section of the lead body (105), such that the loop section circumferentially surrounds the loop opening (115).

2. An implantable medical lead assembly (100) according to claim 1, wherein in the first configuration of the lead body (105), the loop section comprises at least the first pole section (130), preferably at least the first poles section (130) completely and the first cable section (110) partially or completely.

3. An implantable medical lead assembly (100) according to claim 1 or 2, wherein the connecting means (120) can be mounted so as to be movable relative to a region of the lead body (105) in such a way that the loop section can be enlarged or reduced by a movement of the lead body (105).

4. An implantable medical lead assembly (100) according to one of the aforementioned claims, wherein the connecting means (120) comprises a connecting element, e.g. a clipping device, that is firmly connected to a first mounting section of the lead body (105) and movable connected to a second mounting section proximal located to the first mounting section.24.122P-WO / 05.11.20255. An implantable medical lead assembly (100) according to one of claims 1 to 4, wherein the connecting means (120) comprises a connecting element, e.g. a material bond, that is firmly connected to a first mounting section of the lead body (105) and firmly connected to a second mounting section proximal located to the first mounting section.

6. An implantable medical lead assembly (100) according to one of the aforementioned claims, wherein the connecting means (120) comprises a connecting device, e.g. a sleeve (122) or a catheter section (123), that is movable connected to a first mounting section of the lead body (105) and movable connected to a second mounting section proximal located to the first mounting section.

7. An implantable medical lead assembly (100) according to one of the aforementioned claims, wherein the connecting means (120) comprises an eyelet with a through- opening or a clipping device with an open recess, wherein the eyelet or the clipping device is configured such that a region of the lead body (105) can be or is located within the through-opening or the open recess.

8. An implantable medical lead assembly (100) according to one of the aforementioned claims,wherein the lead body (105) comprises an inner lumen,wherein the inner lumen extends in the longitudinal direction of the lead body (105) and is configured such that a mandrin can be inserted into the inner lumen.

9. An implantable medical lead assembly (100) according to one of the aforementioned claims,wherein the lead body (105) is pre-bent two-dimensionally or three-dimensionally, wherein preferably in a section which, in the first configuration of the lead body (105), is part of the loop section, the lead body (105) is pre-bent two-dimensionally or three- dimensionally.

10. An implantable medical lead assembly (100) according to one of the aforementioned claims,24.122P-WO / 05.11.2025wherein the medical lead assembly (100) comprises a second electrically conductive pole section (140), wherein the first pole section (130) and the second pole section (140) are spatially separated from each other by the first cable section (110), wherein in the first configuration of the lead body (105), the loop section comprises both the first pole section (130) and the second pole section (140).

11. An implantable cardiac electronic device comprising an implantable medical lead assembly (100) according to one of the aforementioned claims, wherein preferably the implantable medical lead assembly (100) is configured to be transplanted substernal.

12. An implantable cardiac electronic device according to claim 11, wherein the cardiac electronic device is configured in a way that the first pole section (130) is a shock electrode for defibrillation or a heart stimulation electrode for pacing.

13. An implantable cardiac electronic device according to claim 12 as far as referring back to claim 10, wherein the implantable cardiac electronic device is configured in a way that the first pole section (130) is a shock electrode for defibrillation and the second pole section (140) is a heart stimulation electrode for pacing.

14. Method for providing an implantable medical lead assembly (100) with a loop section of a lead body (105), comprising the steps:A) Providing a lead body (105) and a connecting means (120),B) Firmly or flexibly connecting a first mounting section of the leady body (105) to a second mounting section of the lead body (105) proximal to the first mounting section (125) via the connecting means, such that the lead body (105) and the connecting means (120) together form a closed loop surrounding a loop opening (H5).

15. Method according to claim 11, wherein step A) comprises the following steps:Al) Providing a connecting means (120) with a connecting element,A2) Firmly fixing the connecting element to a distal end section (125) of the lead body (105).24.122P-WO / 05.11.2025

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