Extravascular lead design with segmented, partially electrically isolated defibrillator coil for optimized pacing and sensing

Abstract

A lead body is described, the lead body having a defibrillation electrode positioned along a distal portion of the lead body. The defibrillation electrode includes a plurality of electrode segments spaced a distance from each other. At least one of the plurality of defibrillation electrode segments includes at least one coated portion and at least one uncoated portion. The at least one coated portion is coated with an electrically insulating material configured to prevent transmission of low voltage signals (e.g., pacing pulses) while allowing transmission of high voltage signals (e.g., cardioversion defibrillation shocks). The at least one uncoated portion is configured to transmit both low voltage signals and high voltage signals. The lead may also include one or more discrete electrodes proximal to, distal to, or between the defibrillation electrode segments.

Description

[0001] This application is a divisional application of an invention patent application with an international application date of 2015-11-02, international application number of PCT / US2015 / 058580, application number of 201580060435.8 entering the Chinese national phase, and titled "Extravascular lead design for optimized pacing and sensing with a segmented, partially electrically insulated defibrillator coil". Technical Field

[0002] The present application relates to electrical stimulation leads, and more particularly, to electrical stimulation leads with improved defibrillation, sensing and / or pacing capabilities for extravascular and / or extracardiac (eg, subcutaneous or substernal) applications. Background Art

[0003] Malignant tachycardia (e.g., ventricular fibrillation) is an uncoordinated contraction of the heart muscle of the heart's ventricles and is the most commonly identified arrhythmia in patients with cardiac arrest. If the arrhythmia persists for more than a few seconds, it can lead to cardiogenic shock and interruption of effective blood circulation. As a result, sudden cardiac death (SCD) can occur in just a few minutes.

[0004] In patients who are at high risk for ventricular fibrillation, the use of an implantable cardioverter-defibrillator (ICD) system has been shown to be beneficial in preventing SCD. An ICD system includes an ICD, which is a battery-powered shock device that can include an electrical shell electrode (sometimes called a can electrode) that is coupled to one or more electrical leads placed in the heart. If an arrhythmia is sensed, the ICD can send pulses via the electrical lead wires to shock the heart and restore its normal rhythm. Due to the inherent surgical risks of attaching and replacing electrical leads directly in or on the heart, subcutaneous ICD systems have been designed to provide shocks to the heart without placing electrical leads in the heart or attaching wires directly to the heart.

[0005] The electrical leads used in subcutaneous systems typically include a single dedicated defibrillation electrode and one or more dedicated pacing and / or sensing electrodes along the length of the lead. Each of these electrodes is electrically connected to a separate conductor within the lead body and connected to the ICD. Thus, the ability of the electrical lead to deliver a defibrillation shock, a pacing pulse, or sense cardiac depolarization is fixed to the specific longitudinal or radial placement of each electrode. Summary of the invention

[0006] The present application advantageously provides an implantable medical electrical lead. The medical electrical lead comprises: an elongated lead body having a proximal end and a distal end portion. A defibrillation electrode positioned along the distal end portion of the lead body is included, the defibrillation electrode comprising a plurality of electrode segments spaced a distance from each other. At least one of the plurality of defibrillation electrode segments comprises at least one coated portion and at least one uncoated portion. The at least one coated portion is coated with an electrically insulating material configured to transmit a pacing pulse to a patient's heart and configured to allow a defibrillation shock to be transmitted to the heart. The at least one uncoated portion is configured to transmit a defibrillation shock and to at least one of transmitting a pacing pulse to the heart and sensing cardiac depolarization. An electrical conductor disposed within the elongated lead body is included, each of the plurality of defibrillation electrode segments being electrically coupled to the electrical conductor.

[0007] In another embodiment, the implantable medical lead comprises: an elongated lead body having a proximal end and a distal end portion. A defibrillation electrode positioned along the distal end portion of the lead body is included, the defibrillation electrode comprising a plurality of electrode segments spaced a distance from each other. At least a portion of each of the plurality of defibrillation electrode segments is configured to deliver a defibrillation shock and to deliver a pacing pulse to the heart and to sense a cardiac depolarization pulse from a common location on each of the plurality of defibrillation electrodes. An electrical conductor disposed within the elongated lead body is included, and each of the plurality of defibrillation electrodes is electrically coupled to the electrical conductor.

[0008] In yet another embodiment, the implantable electrical lead comprises: an elongated lead body having a proximal end and a distal end portion. An electrical conductor is disposed within the elongated lead body. A first defibrillation coil segment and a second defibrillation coil segment are each positioned along the distal end portion. The first defibrillation coil segment and the second defibrillation coil segment are spaced a distance from each other and are electrically coupled to the electrical conductor. When a voltage is applied to the electrical conductor, the first defibrillation coil segment and the second defibrillation coil segment have the same polarity. The first defibrillation coil segment and the second defibrillation coil segment each include at least one coated portion coated with tantalum pentoxide and at least one uncoated portion that is not coated with tantalum pentoxide. The at least one uncoated portion is configured to deliver a defibrillation shock and to deliver a pacing pulse to the heart and to sense cardiac depolarization. When the distal end portion of the elongated lead is positioned subcutaneously and substernally between a first position proximal to the xiphoid process and a second position above the xiphoid process, the at least one uncoated portion is positioned above the right ventricle.

[0009] In yet another embodiment, a method for implanting a medical electrical lead is provided. The implantable medical electrical lead includes: an elongated lead body having a proximal end and a distal end; a defibrillation electrode positioned along the distal end of the lead body, the defibrillation electrode including a plurality of electrode segments spaced apart by a distance, at least one of the plurality of defibrillation electrode segments including at least one coated portion and at least one uncoated portion, the at least one coated portion being coated with an electrically insulating material configured to prevent transmission of pacing pulses to a patient's heart and configured to allow transmission of a defibrillation shock to the heart, the at least one uncoated portion being configured to transmit a defibrillation shock and to at least one of transmitting a pacing pulse to the heart and sensing cardiac depolarization. The lead may also include: an electrical conductor disposed within the elongated lead body, each of the plurality of defibrillation electrode segments being electrically coupled to the electrical conductor. In other examples, the lead may include: a connector at a proximal end of the lead; a first electrical conductor disposed within the elongated lead body, the first conductor having a distal end coupled to the first defibrillation electrode segment and a proximal end coupled to the connector; and a second electrical conductor disposed within the elongated lead body, the second conductor having a distal end coupled to the second defibrillation electrode segment and a proximal end coupled to the connector. The method includes: creating an incision at a first location proximate to the center of a patient's torso; introducing an implantation tool into the patient through the incision at the first location; advancing a distal end of the implantation tool through a substernal space below the sternum to form a substernal tunnel; and introducing the medical electrical lead into the substernal tunnel such that a distal portion of the elongated lead body is positioned between a first location proximate to the xiphoid process and a second location above the xiphoid process such that at least one of the plurality of defibrillation electrode segments is positioned in front of and substantially above a ventricle of the heart.

[0010] In another embodiment, an implantable medical electrical lead comprises: an elongated lead body having proximal and distal portions; a defibrillation electrode positioned along the distal portion of the lead body, the defibrillation electrode comprising a plurality of electrode segments spaced apart by a distance less than approximately five centimeters, at least one of the plurality of defibrillation electrode segments comprising at least one coated portion and at least one uncoated portion, the at least one coated portion being coated with an electrically insulating material configured to prevent transmission of pacing pulses to a patient's heart and configured to allow transmission of a defibrillation shock to the heart, the at least one uncoated portion being configured to transmit a defibrillation shock and to at least one of deliver a pacing pulse to the heart and sense cardiac depolarization.

[0011] In another embodiment, an extravascular implantable cardioverter-defibrillator (ICD) system includes an extravascular implantable medical electrical lead and an ICD coupled to the extravascular lead. The extravascular implantable medical electrical lead includes a plurality of defibrillation electrode segments, the plurality of defibrillation electrode segments including a first defibrillation electrode segment and a second defibrillation electrode segment, the second defibrillation electrode segment being positioned distal to the first defibrillation electrode segment. The lead also includes: a connector at a proximal end of the lead; a first electrical conductor disposed within the elongated lead body, the first conductor having a distal end coupled to the first defibrillation electrode segment and a proximal end coupled to the connector; and a second electrical conductor disposed within the elongated lead body, the second conductor having a distal end coupled to the second defibrillation electrode segment and a proximal end coupled to the connector. The ICD includes: a therapy module configured to generate and deliver electrical stimulation therapy; and a switch module configured to selectively couple the therapy module to an electrode vector, wherein both the first defibrillation electrode segment and the second defibrillation electrode segment simultaneously function as a cathode or an anode for delivering electrical stimulation therapy (e.g., cardioversion / defibrillation therapy or pacing therapy). The switch can also independently couple the therapy module to each of the first and second electrode segments to form an electrode vector that includes only one of the defibrillation electrode segments as an anode or a cathode.

[0012] The present disclosure is intended to provide an overview of the subject matter described in this disclosure. It is not intended to provide an exclusive or exhaustive explanation of the technology described in detail in the following figures and descriptions. The following figures and descriptions set forth further details of one or more examples. Other features, objects, and advantages will become apparent from the description and drawings and the statements provided below. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present application and its attendant advantages and features will be more readily understood by referring to the following detailed description in conjunction with the accompanying drawings, wherein:

[0014] Figure 1 is a front view of an extravascular medical electrical lead implanted subcutaneously close to the heart and constructed according to the principles of the present application;

[0015] Figure 2 yes Figure 1 A side view of an extravascular medical electrical lead implanted substernally proximal to the heart is shown;

[0016] Figure 3 yes Figure 1 A front view of an extravascular medical electrical lead is shown;

[0017] Figure 4is a front view of another embodiment of an extravascular medical electrical lead constructed according to the principles of the present application;

[0018] Figure 5 is a front view of another embodiment of an extravascular medical electrical lead constructed according to the principles of the present application;

[0019] Figure 6 is a front view of another embodiment of an extravascular medical electrical lead constructed according to the principles of the present application; and

[0020] Figure 7 is a front view of another embodiment of an extravascular medical electrical lead constructed according to the principles of the present application;

[0021] Figure 8 is a front view of another embodiment of an extravascular medical electrical lead constructed according to the principles of the present application; and

[0022] Fig. 9 is a front view of another embodiment of an extravascular medical electrical lead constructed according to the principles of the present application;

[0023] Fig.10 is a front view of another embodiment of an extravascular medical electrical lead constructed according to the principles of the present application; DETAILED DESCRIPTION

[0024] As used herein, relational terms such as "first" and "second," "upper" and "lower" may be used solely to distinguish one entity or element from another entity or element without necessarily or implying any physical or logical relationship or order between these entities or elements.

[0025] The present disclosure describes an implantable medical electrical lead, an implantable system utilizing such a lead, a technique for providing electrical stimulation therapy using such a lead, and a method for implanting such a lead. An exemplary implantable medical electrical lead includes: an elongated lead body having a proximal and distal portion. The lead includes: a defibrillation electrode positioned along the distal portion of the lead body. The defibrillation electrode includes at least two electrode segments made of a conductive material and spaced apart from each other by a distance. Between the defibrillation electrode segments is an insulating portion, which in some cases may be a part of the lead body. In some cases, when used to deliver therapy and / or sense cardiac electrical signals, the two defibrillation electrode segments are used as a common anode or cathode. For example, the two or more defibrillation electrode segments are electrically coupled to a common electrical conductor within the lead body. In other cases, the two or more defibrillation electrode segments may be coupled to separate electrical conductors within the lead body. In this case, each of the cardiac defibrillation electrode segments may be used independently. In addition, the ICD may include components capable of coupling both of the electrical conductors to the therapy circuitry and / or the sensing circuitry such that the two or more defibrillation electrode segments can be simultaneously activated by the ICD. For example, the ICD may include a switch module that may include a switch array, a switch matrix, a multiplexer, or any other type of switching device suitable for selectively coupling the defibrillation electrode segments (independently or simultaneously) to the therapy circuitry and / or the sensing circuitry.

[0026] At least one of the defibrillation electrode segments includes at least one coated portion and at least one uncoated portion. The at least one coated portion is coated with an electrically insulating material (e.g., tantalum pentoxide) that is capable of blocking or substantially attenuating signal transmission below a certain voltage level, such as a voltage associated with delivering a pacing pulse (e.g., less than 40 volts), while allowing signal transmission above a certain voltage level, such as a voltage associated with a high voltage defibrillation or cardioversion shock (e.g., greater than 600 volts). The electrically insulating material may extend around the entire circumference of at least one coated portion of the (multiple) defibrillation electrode segment. On the other hand, the at least one uncoated portion of the defibrillation electrode segment allows transmission of low voltage signals as well as high voltage signals. Thus, the uncoated portion of the defibrillation electrode segment can be used for low voltage applications, such as transmitting pacing pulses to the heart and / or sensing cardiac activity of the heart. In this way, the entire electrode surface is used to transmit high voltage stimulation pulses, while only the (multiple) uncoated portions of the defibrillation electrode surface are used to transmit pacing pulses and / or sense cardiac electrical signals.

[0027] In one example, only one of the defibrillation electrode segments includes a coated portion and an uncoated portion. The other (multiple) defibrillation electrode segments may be fully coated. In another example, both of the electrode segments include one or more coated portions and an uncoated portion. Several different lead configurations are described herein, having various arrangements of coated portions and uncoated portions along the length of the defibrillation electrode segments.

[0028] In some cases, the defibrillation electrode can be the only electrode such that it provides stimulation and senses electrical signals of the heart. Alternatively, one or more discrete electrodes can be placed along the distal portion of the lead to provide additional pacing and / or sensing functions. As will be described in further detail herein, the (multiple) discrete electrodes can be disposed at multiple locations along the distal portion of the lead, including distal to the defibrillation electrode segment, between two of the defibrillation electrode segments, proximal to the defibrillation electrode segment, or various combinations thereof. The discrete electrodes are coupled to an electrical conductor within the lead body, and the lead body is separate from the (multiple) electrical conductors coupled to the defibrillation electrode segments.

[0029] Referring now to the drawings, in which like reference numerals refer to the same elements throughout, Figure 1-3 An exemplary extravascular and / or extracardiac medical system constructed according to the principles of the present application is shown. The extravascular and / or extracardiac medical system includes an implantable cardioverter defibrillator (ICD) 32 coupled to an electrical stimulation lead generally designated as "10". Lead 10 may include an elongated lead body 12 sized to be positioned proximal to the heart ( Figure 1 ) or below the sternum ( Figure 2 ) implant. For example, lead 10 may extend subcutaneously toward the center of the patient's torso (e.g., toward the patient's xiphoid process). At a location proximal to the xiphoid process, lead body 12 may be bent or otherwise rotated and extended above the thorax subcutaneously or below the sternum in a direction substantially parallel to the sternum. Although Figure 1 1 is shown as being laterally offset from the sternum and extending substantially parallel to the sternum, but lead 10 may be implanted in other locations, such as above the sternum, below the sternum (e.g. Figure 2 ), offset to the right side of the sternum, angled laterally from the proximal or distal end of the sternum, etc. Alternatively, lead 16 may be placed along other subcutaneous paths. The path of lead 16 may depend on the location of ICD 14 or other factors.

[0030] In one example, the distal portion of lead 10 can be implanted in the anterior mediastinum. The anterior mediastinum can be viewed as being bounded laterally by the pleura, posteriorly by the pericardium, and anteriorly by the sternum. In some cases, the anterior wall of the anterior mediastinum can also be formed by the transverse thoracic muscle and one or more costal cartilages. The anterior mediastinum includes a certain amount of loose connective tissue (such as alveolar tissue), some lymphatic vessels, lymph glands, retrosternal muscle tissue (such as the transverse thoracic muscle), branches of the internal thoracic artery, and the internal thoracic vein. In one example, the distal portion of lead 10 can be substantially implanted in the loose connective tissue and / or substernal muscle tissue of the anterior mediastinum.

[0031] In other embodiments, the distal portion of lead 10 can be implanted in other non-vascular locations, extracardiac locations, or extrapericardial locations, including spaces, tissues, or other anatomical features around and adjacent to but not inserted into the pericardium or other portions of the heart, and not above the sternum or thoracic cavity. Thus, lead 10 can be implanted at any location within the "substernal space" defined by the lower surface between the sternum and / or thoracic cavity and the body cavity, but not including the pericardium or other portions of the heart. The substernal space can alternatively be referred to by the terms "retrosternal space" or "mediastinum" or "intrasternal" as known to those skilled in the art, and includes the anterior mediastinum. The substernal space may also include the anatomical region described in Baudoin, YP, et al., entitled "The superior epigastric artery does not pass through Larrey's space (trigonum sternocostale)," in Surg. Radiol. Anat. 25.3-4 (2003): 259-62. In other words, the distal portion of lead 10 may be implanted in an area around the outer surface of the heart, but not attached to heart 26. Furthermore, in some cases, the substernal space may include within the pleura.

[0032] The lead body 12 can have a generally consistent shape along the length of the lead body 12. In one example, the lead body 12 can have a generally tubular or cylindrical shape and can define a diameter of approximately 3-9 flanges (Fr), however, lead bodies 12 less than 3Fr and greater than 9Fr can also be used. In another configuration, the lead body 12 can have a flat, ribbon-like or paddle-like shape along at least a portion of the length of the lead body 12. In this example, the width across the lead body 12 can be between 1mm and 3.5mm. Other lead body 12 designs can be used without departing from the scope of the present application. The lead body 12 of the lead 10 can be formed of a non-conductive material (including silicone, polyurethane, fluoropolymer, mixtures thereof, and other suitable materials) and molded to form one or more lumens (not shown), however, these techniques are not limited to such structures.

[0033] Lead body 12 may include proximal end 14 and distal portion 16, distal portion 16 includes one or more electrodes, the one or more electrodes are configured to deliver electrical energy to the heart or sense electrical energy in the heart. Distal portion 16 can be anchored to a desired position in the patient's body (e.g., substernal or subcutaneous) by suturing distal portion 16 to the muscle tissue, tissue or bone of the xiphoid process entry site of the patient. Alternatively, distal portion 16 can be anchored to the patient, or anchored by using rigid tines, forks, barbs, clips, screws and / or other protruding elements or flanges, discs, flat teeth, flaps, porous structures (such as mesh elements for joining that are conducive to tissue growth), bioadhesive surfaces and / or any other non-perforated elements. For example, distal portion 16 can be anchored close to xiphoid process or close to a higher sternal region.

[0034] The distal portion 16 may include a defibrillation electrode 18. The defibrillation electrode 18 includes a plurality of defibrillation electrode segments disposed along at least a portion of its length. The plurality of defibrillation electrode segments 20 may be positioned toward a portion of the lead body 12 extending, for example, from above the xiphoid process. Figure 1-3 In the illustrated example, the defibrillation electrode 18 includes a first defibrillation electrode segment 20a and a second defibrillation electrode segment 20b that is positioned distal to and spaced a distance from the first defibrillation electrode segment 20a. Between the first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b is an insulating portion, which in some cases may be part of the lead body 12. Although in Figure 1-32, but it is contemplated that more than two of the plurality of defibrillation electrode segments 20 may be positioned along the distal portion 16. In one configuration, each of the plurality of defibrillation electrode segments 20 may be a coil electrode formed of a conductor. The electrode segments 20 may be formed of any of a variety of conductive materials, including but not limited to metals, metal oxides, metal alloys, coated metals, and composite materials based on platinum, gold, iridium, titanium, tantalum, vanadium, aluminum, copper, zirconium, carbon, graphene, diamond, zirconium, diamond-like coatings (DLC), silicon, and / or boron. This also includes glass and dielectric materials such as borosilicate or chalcogenide glasses, zirconium oxide, aluminum oxide, and conductive polymers, semiconductors, and conductive ceramics in pure form or with additives such as boron, carbon, gold, silver, and similar metal particles and / or fibers from micrometer to nanometer sizes. In another configuration, each of the plurality of defibrillation electrode segments 20 may be a flat ribbon electrode segment, a paddle electrode segment, a braided or woven electrode segment, a mesh electrode segment, a directional electrode segment, a patch electrode segment, or other type of electrode segment configured to deliver a defibrillation shock to a patient's heart.

[0035] In an exemplary configuration, the first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b are coil electrodes disposed in line with, around the exterior of, or within the wall of the lead body 12. The first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b may each be approximately 1 cm-10 cm in length, more preferably 2 cm-6 cm in length, and even more preferably 3 cm-5 cm in length, and lengths greater than 10 cm and less than 1 cm may be used without departing from the scope of the present disclosure. The first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b may be the same length, or each segment may have a different length.

[0036] In one example, the first defibrillation electrode segment 20a can be spaced apart from the second defibrillation electrode segment 20b by about 1 mm-3 cm. In another example, the first defibrillation electrode segment 20a can be spaced apart from the second defibrillation electrode segment 20b by about 0.5 cm-2 cm. In a further example, the first defibrillation electrode segment 20a can be spaced apart from the second defibrillation electrode segment 20b by about 0.5 cm-1 cm. In another example, the first defibrillation electrode segment 20a can be positioned proximal to the second defibrillation electrode segment 20b and spaced apart from the second defibrillation electrode segment 20b by about 2 mm-10 mm.

[0037] Each of the plurality of defibrillation electrode segments 20a and 20b may include at least one coated portion 26a and 26b, respectively, and at least one uncoated portion 28a and 28b, respectively, located at any longitudinal position along each of their respective lengths. Figure 1-3In the illustrated example, the uncoated portion 28a is disposed at the distal end of the first defibrillation electrode segment 20a, and the uncoated portion 28b is disposed at the proximal end of the second defibrillation electrode segment 20b. However, as described in further detail herein, the coated portion 26 and the uncoated portion 28 may be disposed at other locations along the length of the defibrillation electrode segment 20, such as at the proximal end, the distal end, or any location therebetween. In addition, one or both of the defibrillation electrode segments 20a or 20b may include more than one coated portion 26 and / or more than one uncoated portion 28, such as an uncoated portion 28 between two coated portions 26 or a coated portion 26 between two uncoated portions 28. In other cases, only one of the defibrillation electrode segments 20a or 20b may include a coated portion 26 and / or an uncoated portion 28, while the other of the defibrillation electrode segments 20 is completely coated or uncoated.

[0038] Each coated portion 26 of the plurality of defibrillation electrode segments 20 may be coated with an electrically insulating material that substantially blocks, interrupts, or attenuates the delivery or transmission of low voltage signals (e.g., signals having a voltage less than 100 volts) while not substantially blocking, interrupting, or attenuating the delivery or transmission of high voltage signals (e.g., signals having a voltage greater than 500 volts). In this manner, the entirety of each of the plurality of defibrillation electrode segments 20 (i.e., the uncoated portion(s) 28 in combination with the coated portion(s) 26) is configured for delivering high voltage therapy, such as a defibrillation or cardioversion shock, and each of the uncoated portions 28 of each of the plurality of electrode segments 20 is configured for: delivering low voltage therapy, such as one or more pacing pulses of varying voltage for anti-tachycardia pacing, post-shock pacing, bradycardia pacing, high-speed pacing for VF induction, and / or entrainment pacing pulses prior to a T shock for VF induction; and / or sensing low voltage signals (e.g., cardiac depolarization).

[0039] The electrically insulating material may extend around the entire circumference of the coated portion 26 of the defibrillation electrode segment 28. The electrically insulating material may be any of a variety of materials, such as tantalum pentoxide, titanium oxide, zirconium oxide, vanadium oxide, niobium oxide, doped silicon, silicon dioxide, boron doped diamond, doped glass, ceramic coating, or polymer composite material or other materials having the property of substantially preventing the transmission or delivery of low voltages while substantially not preventing the transmission or delivery of high voltages. The thickness of the insulating material may have a thickness that varies based on the following: the material type of the electrode segment 20, the type of insulating material, the size of the coated portion 26, the expected depth and location of the distal portion 16 (e.g., substernal or subcutaneous location, etc.). For example, for tantalum pentoxide, the thickness of the coating may be in the range of approximately greater than or equal to 0.2 microns to less than or equal to 2.0 microns. However, other thicknesses may be used without departing from the scope of the present disclosure. In one example, the coating portion 26 is coated with tantalum pentoxide having a thickness of 0.6 micrometers to 0.9 micrometers, which significantly blocks up to 90V of electrical pulses toward the patient's heart and prevents the sensing of cardiac depolarization events to determine whether electrical stimulation therapy should be delivered to the heart. However, at higher voltages (e.g., at voltages above 90V), the voltage overcomes the electrical insulating properties of tantalum pentoxide and a defibrillation shock can be delivered to the heart.

[0040] The sizes of the coated portions 26 and the uncoated portions 28 can vary. In some configurations, the uncoated portions 28 can be less than or equal to 25% of the length of the corresponding electrode segment 20. In another exemplary configuration, the uncoated portions 28 can be less than or equal to 10% of the length of the corresponding electrode segment 20. In other cases, the surface area of ​​each of the uncoated portions 28 can be less than or equal to 25% of the total surface area of ​​the corresponding defibrillation electrode segment 20 or less than or equal to 10% of the total surface area of ​​the corresponding defibrillation electrode segment 20. In yet other examples, the combined length and / or surface area of ​​all uncoated portions 28 of a segment 20 can be less than or equal to 25% of the total length or surface area of ​​the plurality of segments 20 or less than or equal to 10% of the total length or surface area of ​​the plurality of segments 20. Alternatively, in some examples, each of the uncoated portions 28 has a surface area less than or equal to 100 square millimeters (mm 2 ) surface area. In other cases, the uncoated portion 28 may have a surface area less than or equal to 10 mm 2 The uncoated portion and the coated portion may have dimensions different from those described above.

[0041] Various arrangements of each uncoated portion 28 and each coated portion 26 are contemplated and will be discussed in greater detail below. In certain embodiments, one or more of the uncoated portions 28 of the first defibrillation electrode segment 20a and / or the second defibrillation electrode segment 20b can be positioned over any desired chamber or region of the patient's heart. For example, the distal portion 16 of the lead body 12 can be positioned above the cardiac silhouette, as seen under anterior-posterior fluoroscopy, such that the uncoated portions 28a of the first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b are both substantially positioned over the ventricle or other cardiac target. In one example, the distal portion 16 of the lead body 12 can be positioned over the cardiac silhouette, as seen under anterior-posterior fluoroscopy, such that the insulating portions between the defibrillation electrode segments 20 are substantially centered over the ventricle or other cardiac target. As described in detail herein, the uncoated portion 28 is used to deliver pacing pulses and / or sense cardiac depolarization (low voltage function), and to deliver high voltage defibrillation or cardioversion shocks (high voltage function). Multiple defibrillation electrode segments 20 may also be positioned on the right ventricle or above the heart or at other locations along the lead body but not directly above the heart so that multiple therapy vectors can be generated along the length of the distal portion 16, as discussed in more detail below.

[0042] The lead body 12 may also include one or more discrete electrodes 34 and / or 36 positioned along the distal portion 16. Figure 1-3 In the illustrated example, the electrode 34 is located proximal to the first defibrillation electrode segment 20a, and the electrode 36 is located distal to the second defibrillation electrode segment 20b. The electrodes 34 and 36 are spaced apart from the corresponding defibrillation electrode segment 20 by a distance. In one example, the electrodes 34 and 36 are spaced apart from the corresponding defibrillation electrode segment 20 by a distance greater than or equal to 2 mm and less than or equal to 1.5 cm. In another example, the electrodes 34 and 36 are spaced apart from the corresponding defibrillation electrode segment 20 by a distance greater than or equal to 5 mm and less than or equal to 1 cm. In yet another example, the electrodes 34 and 36 are spaced apart from the corresponding defibrillation electrode segment 20 by a distance greater than or equal to 6 mm and less than or equal to 8 mm. However, the electrodes 34 and 36 may be spaced apart from the corresponding defibrillation electrode segment by a distance greater than 1.5 cm in other configurations, particularly when the discrete electrodes are located proximal to all defibrillation electrode segments 20 and distal to all defibrillation electrode segments 20.

[0043] Electrode 34 is shown as a ring electrode, and electrode 36 is shown as a hemispherical tip electrode. However, electrodes 34 and 36 may include any type of electrode in a variety of different types of electrodes, including ring electrodes, short coil electrodes, paddle electrodes, hemispherical electrodes, directional electrodes, etc., and may be positioned at any position along the distal portion 16. Further, electrodes 34 and 36 may have similar types, shapes, sizes and materials or may be different from each other. In another embodiment, for example, electrode 36 may not be a tip electrode, but may be located proximal to the distal end of lead body 12 and distal to second defibrillation electrode segment 20b. Discrete electrodes 34 and 36 may be low voltage electrodes configured to deliver pacing pulses to the heart and / or sense cardiac depolarization of the heart. Each electrode 34 and 36 may be coupled to its own conductor, such as one or more wires disposed in a separate lumen of lead body 12, so that each electrode 34 and 36 may be independently activated by ICD 32. In other embodiments, lead body 12 may include a single discrete electrode (e.g., electrode 34 or 36) or more than two discrete electrodes positioned along distal portion 16. In another embodiment, lead body 12 may not include any discrete electrodes along distal portion 16 of lead body 12. In this case, defibrillation electrode segment 20 is the only electrode of lead 10 used for low voltage functions (e.g., sensing or pacing) and for high voltage electrical stimulation therapy.

[0044] In some cases, the lead body 12 is formed from the distal end of the lead body 12 to the proximal electrode (e.g., at Figure 1 The proximal side distal portion of the electrode 34 in the example may be less than or equal to 15 cm and more preferably less than or equal to 13 cm and even more preferably less than or equal to 10 cm.

[0045] The proximal end 14 of the lead body 12 may include one or more connectors 30 (best seen at Figure 3 ) to electrically couple the lead 10 to an implantable cardioverter defibrillator (ICD) 32 implanted subcutaneously or intramuscularly in the patient's body (e.g., in the patient's left armpit). The ICD 32 may include a housing 33 that forms an airtight seal to protect the various components of the ICD 32. The housing 33 of the ICD 32 may be formed of a conductive material such as titanium or a titanium alloy, and the housing 33 may be used as a connector between the housing 33 and the distal portion 16. Figure 133. The ICD 32 may also include a connector assembly including electrical feedthroughs through which electrical connections are made between one or more connectors 30 of the leads 10 and electronic components contained within the housing 33. The housing 33 may house one or more processors, memories, transmitters, receivers, sensors, sensing circuitry, therapy circuitry (which may include, for example, pulse generator(s), transformer(s), capacitor(s), etc.), switching modules, power supplies (capacitors and batteries), and other appropriate components.

[0046] As described above, the defibrillation electrode segment 20 can be used as a common electrode. In this configuration, both the first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b can be used simultaneously as an anode or cathode of an electrode vector for providing electrical stimulation therapy to a patient and / or sensing electrical signals of the patient's heart. In other words, when the electrical conductors coupled to the first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b are electrically coupled to the treatment circuit and / or sensing circuit inside the ICD 32, the uncoated portion is used as a single anode / cathode for pacing and / or sensing applications. For example, a single wire conductor (not shown) can be disposed within the lumen of the lead body 12, which is electrically coupled to the connector 30. The single conductor can be branched into two or more wire conductors in the lead body 12 at a predetermined longitudinal position to connect to each of the plurality of electrode segments 20. Alternatively, a first conductor may be connected to the first defibrillation electrode segment 20a and a second conductor may connect the first defibrillation electrode segment 20a to the second defibrillation electrode segment 20b such that applying a voltage to the first conductor applies the same voltage to the first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b.

[0047] In other configurations, the first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b are connected to separate conductors within the lead body 12. For example, a first electrical conductor disposed within the elongated lead body 12 may have a distal end coupled to the cardiac defibrillation electrode segment 20a and a proximal end coupled to the connector 30, and a second electrical conductor disposed within the elongated lead body 12 may have a distal end coupled to the second cardiac defibrillation electrode segment 20b and a proximal end coupled to the connector 30. In this case, each defibrillation electrode segment 20 may be independently used as part of an electrode vector. In addition, the ICD 32 may include components capable of simultaneously coupling two electrical conductors to a therapy circuit system so that the defibrillation electrode segments may be simultaneously activated by the ICD 32. For example, the ICD 32 may include a switching circuit system or a switch module for selecting which available electrodes are used to deliver the electrical stimulation therapy. The switch module may include a switch array, a switch matrix, a multiplexer, or any other type of switching device suitable for selectively coupling electrodes to the therapy circuit system. Thus, the ICD 32 can use the switch module to select electrodes 20a, 20b, 33, 34, and / or 36 as an electrode vector for delivering the therapy. Where defibrillation electrode segments 20a and 20b are coupled to separate conductors, the ICD 32 can selectively couple the therapy circuitry (or sensing circuitry) to either of segments 20a and 20b independently as the anode or cathode of the electrode vector, or to both electrode segments 20A and 20B simultaneously as the cathode or anode of the electrode vector. Similarly, electrodes 34 and 36 and / or other electrodes in the housing electrode 33 can be selected for use as part of an electrode vector (including any of the various electrode vectors described herein) via the switch module.

[0048] ICD 32 can generate and deliver electrical stimulation therapy, including traditional low-voltage stimulation therapy (e.g., anti-tachycardia pacing, post-shock pacing, bradycardia pacing, or pacing used in conjunction with VF induction) and traditional high-voltage stimulation therapy (e.g., cardioversion or defibrillation shock) via various electrode combinations or vectors. In one example, ICD 32 can be configured to deliver low-voltage stimulation therapy via an electrode vector that includes an uncoated portion 28 of an electrode segment 20 as an anode (or cathode) and a housing of ICD 32 as a cathode (or anode). In some cases, this same vector can be used to sense electrical signals of the heart. Similarly, ICD 32 can be configured to deliver voltage stimulation therapy via the electrode vector that includes an electrode segment 20 (both uncoated portion 28 and coated portion 26) as an anode (or cathode) and a housing of ICD 32 as a cathode (or anode). In other cases, the uncoated portions 28a and / or 28b may also be used alone, so that low voltage stimulation therapy can be provided between the uncoated portions 28a and 28b or between either the uncoated portions 28a or 28b and another of the electrodes (e.g., electrode 34, electrode 36 and / or the shell electrode 33).

[0049] The ICD 32 may deliver low voltage electrical energy (e.g., pacing pulses) using various electrode vectors including the uncoated portions 28a and 28b (alone or collectively) and / or the electrode 34 and / or the electrode 36 and / or the shell electrode 33 of the defibrillation electrode segment 20. For example, the ICD 32 may deliver pacing pulses via an electrode vector in which one of the electrode 34, electrode 36, or uncoated portions 28a and 28b (alone or collectively) is the cathode and the shell electrode 33 is the anode, or vice versa. In another example, the ICD 32 may deliver pacing pulses via an electrode vector formed by various pairs or multiple configurations of the electrodes 34, electrode 36, and uncoated portions 28a and 28b (alone or collectively), for example, one or more of the electrodes serve as cathodes and another one or more electrodes serve as anodes. In yet another example, the ICD 32 can deliver pacing pulses via an electrode vector between any combination of electrode 34, electrode 36, and uncoated portion 28 (either individually or collectively) acting simultaneously as cathodes and housing electrode 33 acting as an anode (or vice versa), as in the case of multi-site or multi-point pacing.

[0050] In one example, ICD 32 may be based on the use of Figure 1-10In response to detecting a tachyarrhythmia, the ICD 32 detects a ventricular tachyarrhythmia (eg, VT or VF) by sensing a signal sensed by one of the electrode vectors described herein and using any tachyarrhythmia detection algorithm known in the art. Figure 1-10 In some cases, the ICD 32 can generate and deliver low-energy stimulation therapy via any of the electrode vectors described above, and generate and deliver high-energy stimulation therapy via one or both of the defibrillation electrode segments 20 (either individually or simultaneously).

[0051] In one example, the ICD 32 may deliver pacing (e.g., ATP or post-shock pacing) using an electrode vector that includes one or both of the defibrillation electrode segments 20a and / or 20b. The electrode vector used for pacing may, for example, include electrode segment 20a as a cathode (or anode) and electrode segment 20b and / or one of electrodes 33, 34, or 36 as an anode (or cathode), or segment 20b as a cathode (or anode) and electrode segment 20a and / or one of electrodes 33, 34, or 36 as an anode (or cathode), or segments 20a and 20b together as a common cathode (or anode) and one of electrodes 33, 34, or 36 as an anode (or cathode). If high voltage therapy is necessary, the ICD 14 may deliver a cardioversion / defibrillation shock (or multiple shocks) using both electrode segments 20a or 20b as cathodes and using the housing electrode 33 as an anode.

[0052] The ICD 32 may also generate and deliver electrical stimulation signals for inducing VF, such as high-speed pacing pulses and / or entrainment pacing pulses prior to a T shock. In one example, the ICD 32 may deliver high-speed pacing pulses using an electrode vector between an uncoated portion 28a on the defibrillation electrode segment 20a and an uncoated portion 28b of the defibrillation electrode segment 20b. In another example, the ICD 32 may deliver multiple entrainment pacing pulses (e.g., 3-5 pulses) using an electrode vector between an uncoated portion 28a on the defibrillation electrode segment 20a and an uncoated portion 28b of the defibrillation electrode segment 20b, and then deliver a T wave shock via one or both of the defibrillation electrode segments 20a and 20b.

[0053] Electrode segments 20A and 20B are referred to as defibrillation electrode segments or defibrillation electrodes because they are used individually or collectively to deliver high voltage stimulation therapy (e.g., cardioversion or defibrillation shock). However, electrode segments 20A and 20B may also be used to provide pacing functions, sensing functions, or pacing and sensing functions in addition to or in place of high voltage stimulation therapy. In this sense, the use of the term "defibrillation electrode segments" or "defibrillation electrodes" should not be considered to limit these electrode segments to use only in high voltage applications.

[0054] Figure 4 Another configuration of the distal end portion 40 of another exemplary lead body 42 is shown. The lead body 42 may include Figure 1-3 One or more structures and / or functions of the lead body 12 (and vice versa) are described in detail, including size, material, etc. For the sake of brevity, repeated descriptions of similarly numbered elements described in other embodiments are omitted.

[0055] exist Figure 4 In the example shown, the first defibrillation electrode 20a is positioned proximal to the second defibrillation electrode 20b and is spaced apart from the second defibrillation electrode 20b. In one example, the first defibrillation electrode segment 20a may be spaced apart from the second defibrillation electrode segment 20b by approximately 1 mm-3 cm. In another example, the first defibrillation electrode segment 20a may be spaced apart from the second defibrillation electrode segment 20b by approximately 1 cm-2 cm. In a further example, the first defibrillation electrode segment 20a may be spaced apart from the second defibrillation electrode segment 20b by approximately 1.5 cm. In another example, the first defibrillation electrode segment 20a may be spaced apart from the second defibrillation electrode segment 20b by approximately 1 cm-3 cm. In another example, the first defibrillation electrode segment 20a may be spaced apart from the second defibrillation electrode segment 20b by less than approximately 5 cm. In another example, the first defibrillation electrode segment 20a may be positioned proximal to the second defibrillation electrode segment 20b and be spaced apart from the second defibrillation electrode segment 20b by approximately 2 mm-10 mm. However, other spacing distances between segments 20 (such as described above with respect to Figure 1-3 those separation distances described).

[0056] The first defibrillation electrode segment 20a includes a coated portion 26a distal to an uncoated portion 28a along its length. The second defibrillation electrode segment 20b includes a coated portion 26b proximal to an uncoated portion 28b. The uncoated portion 28 and the coated portion 26 may have the same Figure 1-3 Any dimension described (e.g., surface area or percentage length).

[0057] Spaced between the coated portion 26a of the first defibrillation electrode segment 20a and the coated portion 26b of the second defibrillation electrode segment 20a are discrete electrodes 34a and 34b. The electrodes 34a and 34b can be spaced a distance from the coated portions 26a and 26b, respectively. In one example, the distance between the electrode 34a (or 34b) and the corresponding coated portion 26a (or 26b) can be about 2mm-1cm. In another example, the distance between the electrode 34a (or 34b) and the corresponding coated portion 26a (or 26b) can be about 2mm-6mm. In other embodiments, the distal portion 40 can include no discrete electrodes 34 or include a single discrete electrode 34 or more than two discrete electrodes 34 located between the defibrillation electrode segments 20. In one example, a single short coil electrode (e.g., having a length of about 0.5cm-3cm) can be located between the defibrillation electrode segments 20.

[0058] The distal portion 40 also includes a tip electrode 36, which can substantially mate with the electrode 36 of the distal portion 16. The tip electrode 36 can be located at the distal end of the lead body 40 (as shown) or anywhere distal to the defibrillation electrode segment 20b. In some cases, the distal portion 40 may not include the electrode 36. In addition to or in lieu of the tip electrode 36, the distal portion 40 may include at least one discrete electrode located proximal to the defibrillation electrode segment 20a. In another embodiment, the distal portion 40 may not include any discrete electrodes. The electrodes 34a, 34b, and 36 can be as described above with respect to Figure 1-3 Any of the types, shapes, sizes and materials of the electrodes described, and may be the same or different from each other.

[0059] In this configuration, the ICD 32 can deliver low voltage electrical energy using various electrode vectors including the uncoated portions 28a and 28b (individually or collectively) and / or the electrodes 34a and / or 34b and / or 36 of the defibrillation electrode segment 20 and / or the shell electrode 33. For example, the ICD 32 can deliver pacing pulses via an electrode vector in which one of the electrodes 34a, 34b, 36 or the uncoated portions 28a and 28b (individually or collectively) is the cathode and the shell electrode 33 is the anode, or vice versa. In another example, the ICD 32 can deliver pacing pulses via an electrode vector formed by various pairs or multiple configurations of the electrodes 34a, 34b, 36 and the uncoated portions 28a and 28b (individually or collectively), for example, one or more of the electrodes serve as cathodes and another one or more electrodes serve as anodes. In yet another example, the ICD 32 can deliver pacing pulses via an electrode vector between any combination of electrodes 34a, 34b, 36, and uncoated portion 28 acting simultaneously as cathodes (either individually or collectively) and the housing electrode 33 acting as an anode (or vice versa), as in the case of multi-site or multi-point pacing.

[0060] Figure 5 Another configuration of a distal portion 50 and another exemplary lead body 52 is shown. The lead body 52 may include Figure 1-4 The lead body 12 (or vice versa) described in detail and / or Figure 4 One or more structures and / or functions of the lead body 42 (and vice versa) are described in detail, including size, material, etc. For the sake of brevity, repeated descriptions of similarly numbered elements described in other embodiments are omitted.

[0061] The first defibrillation electrode portion 20a is positioned proximal to the second defibrillation electrode portion 20b and is spaced a distance apart from the second defibrillation electrode segment 20b. The distance between the defibrillation electrode segments 20 may be as described above with respect to Figure 1-4 The first defibrillation electrode segment 20a includes an uncoated portion 28a distal to a coated portion 26a along its length. The second defibrillation electrode segment 20b includes an uncoated portion 28b distal to a coated portion 26b along its length. The coated portion 26 and the uncoated portion 28 may have the same Figure 1-4 Any dimension described (e.g., area or percentage length).

[0062] exist Figure 5In the example shown, the first discrete electrode 34a is disposed proximal to the coated portion 26a of the defibrillation electrode segment 20a, the second discrete electrode 34b is disposed between the uncoated portion 28a of the defibrillation electrode portion 20a and the coated portion 26b of the defibrillation electrode segment 20b, and the third discrete electrode (tip electrode) 36 is disposed distal to the uncoated portion 28b of the defibrillation electrode segment 20b.

[0063] Electrodes 34a, 34b, and 36 are spaced apart from the coated defibrillation electrode segment 20. Electrodes located adjacent any uncoated portion 28 of the defibrillation electrode segment 20 (e.g., Figure 5 The electrodes 34b or 36 in the defibrillation electrode segment 20 may be spaced apart from the adjacent uncoated portion 28 by greater than or equal to 2 mm and less than or equal to 1.5 cm. In another example, the electrodes located near any uncoated portion 28 of the defibrillation electrode segment 20 may be spaced apart from the uncoated portion 28 by greater than or equal to 5 mm and less than or equal to 1 cm. In yet another example, the electrodes located near any uncoated portion 28 of the defibrillation electrode segment 20 may be spaced apart from the uncoated portion 28 by greater than or equal to 6 mm and less than or equal to 8 mm.

[0064] An electrode (e.g., Figure 5 In one embodiment, an electrode 34a or 34b in a defibrillation electrode segment 20 may be spaced apart from an adjacent coated portion 26 by greater than or equal to 2 mm and less than or equal to 1.5 cm. In another example, an electrode located proximate any coated portion 26 of a defibrillation electrode segment 20 may be spaced apart from the coated portion 26 by greater than or equal to 2 mm and less than or equal to 1 cm. In yet another example, an electrode located proximate any coated portion 26 of a defibrillation electrode segment 20 may be spaced apart from the coated portion 26 by greater than or equal to 2 mm and less than or equal to 6 mm. Other electrode spacings may be used without departing from the scope of the present disclosure.

[0065] In other configurations, there may be more or fewer discrete electrodes. For example, the distal portion 50 may include only a single electrode 34b disposed between the defibrillation electrode segments 20. In another example, the distal portion 50 may include an electrode 34b disposed between the defibrillation electrode segments 20 and only one of the discrete electrodes 34a and 36. In still other examples, there may be more than one electrode 34a located proximal to the defibrillation electrode segment 20a and / or more than one electrode 34b located between the defibrillation electrode segments 20 and / or more than one electrode distal to the defibrillation electrode segment 20b, and / or one or more or all of the electrodes 34a, 34b, or 36 may not be present. In addition, any of the electrodes 34a, 34b, and 36 may have similar types, shapes, sizes, and materials, or may be different from one another. In another embodiment, for example, the electrode 36 may not be a tip electrode, but may be located proximal to the distal end of the lead body 12 and distal to the second defibrillation electrode segment 20b.

[0066] In this configuration, the ICD 32 can deliver low voltage electrical energy using various electrode vectors including the uncoated portions 28a and 28b (individually or collectively) and / or the electrodes 34a and / or 34b and / or 36 and / or the shell electrode 33 of the defibrillation electrode segment 20. For example, the ICD 32 can deliver pacing pulses via an electrode vector in which one of the electrodes 34a, 34b, 36 or the uncoated portions 28a and 28b (individually or collectively) is the cathode and the shell electrode 33 is the anode, or vice versa. In another example, the ICD 32 can deliver pacing pulses via an electrode vector formed by various pairs or multiple configurations of the electrodes 34a, 34b, 36 and the uncoated portions 28a and 28b (individually or collectively), for example, one or more of the electrodes serve as cathodes and another one or more electrodes serve as anodes. In yet another example, the ICD 32 can deliver pacing pulses via an electrode vector between any combination of electrodes 34a, 34b, 36, and uncoated portion 28 acting simultaneously as cathodes (either individually or collectively) and the housing electrode 33 acting as an anode (or vice versa), as in the case of multi-site or multi-point pacing.

[0067] Figure 6 Another configuration of a distal portion 60 and another lead body 62 is shown. The lead body 62 may include Figure 1-3 The lead body 12 (and vice versa) described in detail Figure 4 The lead body 42 (and vice versa) described in detail and / or with respect to Figure 5One or more structures and / or functions of the lead body 52 (and vice versa) are described in detail, including size, material, etc. For the sake of brevity, repeated descriptions of similarly numbered elements described in other embodiments are omitted.

[0068] The distal end portion 60 of the lead body 62 is substantially conformable to the defibrillation electrode segments 20a and 20b, except that the coated portions 26a and 26b and the uncoated portions 28a and 28b are different. Figure 5 The distal portion 50 of the lead body 52. Figure 6 In the example shown, the first defibrillation electrode 20a includes a coated portion 26a distal to an uncoated portion 28a along its length, and the second defibrillation electrode portion 20b includes a coated portion 26b distal to an uncoated portion 28b. Figure 1-5 Discrete electrodes 34a, 34b and 36 may be arranged in any of the configurations described.

[0069] In other constructions, the uncoated portions 28a and 28b or the electrodes 34a, 34b and 36 of the lead bodies 12, 42, 52 and 62 can be shaped, oriented, designed or otherwise configured to reduce extracardiac stimulation. For example, the uncoated portions 28a and 28b of the lead body 12 can be shaped, oriented, designed or otherwise configured to focus, direct or point pacing pulses toward the heart. In this manner, pacing pulses delivered by the uncoated portions 28a and 28b are directed toward the heart rather than outward toward skeletal muscle. For example, the coated portion can extend less than or equal to 180 degrees around the circumference of the lead body 12, and less than or equal to 120 degrees in an exemplary construction. In an exemplary construction, as Figure 7 As shown, either or both of the uncoated portions 28a and 28b are disposed in a side-by-side relationship with their respective coated portions 26a and 26b across their respective first defibrillation electrode 20a or second defibrillation electrode 20b, respectively. Figure 7 As shown, at certain longitudinal locations on the lead bodies 12, 42, 52, and 62, the uncoated portions 28a and 28b may be partially disposed around the circumference or periphery of the lead bodies 12, 42, 52, and 62, and the remainder of the circumference or periphery of the lead bodies 12, 42, 52, and 62 may include the insulating material of the coated portions 26a and 26b. At other longitudinal locations of the coated portions 26a and 26b, the electrically insulating material may extend around the entire circumference of the coated portion 26 of the defibrillation electrode segment 20.

[0070] Figure 8 Another configuration of the distal portion 80 and the lead body 82 is shown. The lead body 82 may include Figure 1-3 The lead body 12 (and vice versa), Figure 4lead body 42 (and vice versa), Figure 5 The lead body 52 (and vice versa), Figure 6 lead body 62 (or vice versa) or Figure 7 One or more structures and / or functions of the lead body (or vice versa), including size, material, etc. For the sake of brevity, repeated descriptions of similarly numbered elements described in other embodiments are omitted.

[0071] exist Figure 8 In the example shown, the first defibrillation electrode segment 20a is positioned proximal to and spaced apart from the second defibrillation electrode segment 20b. The distance between the defibrillation electrode segments 20 may be as described above with respect to Figure 1-7 The first defibrillation electrode segment 20a includes a coated portion 26a disposed between the first coated portion 28a and the second coated portion 28a'. The second defibrillation electrode segment 20b also includes a coated portion 26b disposed between the first uncoated portion 28b and the second uncoated portion 28b'. Each of the uncoated portions 28 may have the above Figure 1-7 Alternatively, the total size (eg, surface area or percentage length) of the uncoated portions 28a and 28a' may be any of the dimensions (eg, surface area or percentage length) described above. Figure 1-7 Similarly, the total dimensions (eg, surface area or percentage length) of the uncoated portions 28b and 28b' may be as described above with respect to Figure 1-7 Describe the dimensions.

[0072] Interspersed between the first defibrillation electrode segment 20a and the second defibrillation electrode segment 20b may be discrete electrodes 34a and 34b. In addition, the distal portion 80 also includes a tip electrode 36. However, the distal portion 80 of the lead 82 may include the above-described Figure 1-7 More or fewer discrete electrodes arranged in any manner described. The discrete electrodes may include the above Figure 1-7 Describe the type, spacing, size and / or material.

[0073] Fig. 9 Another configuration of the distal portion 90 and the lead body 92 is shown. The lead body 92 may include Figure 1-3 The lead body 12 (and vice versa), Figure 4 lead body 42 (and vice versa), Figure 5 The lead body 52 (and vice versa), Figure 6 lead body 62 (and vice versa), Figure 7 lead body 72 (or vice versa) and / or Figure 8One or more structures and / or functions of the lead body 82 (and vice versa), including size, material, etc. For the sake of brevity, repeated descriptions of similarly numbered elements described in other embodiments are omitted.

[0074] exist Fig. 9 In the illustrated configuration, only one of the defibrillation electrode segments 20 includes an uncoated portion 28. In particular, the second defibrillation electrode segment 20b includes a coated portion 26b disposed between the first coated portion 28b and the second coated portion 28b'. Each of the uncoated portions 28 may have the same coating properties as described above. Figure 1-7 Alternatively, the total size (eg, surface area or percentage length) of the uncoated portions 28b and 28b' may be any of the dimensions (eg, surface area or percentage length) described above. Figure 1-7 Describe the dimensions.

[0075] The first defibrillation electrode segment 20a is completely coated (as indicated by reference numeral 26a). The distal portion 90 of the lead body 92 also includes a discrete electrode 34 located proximal to the first defibrillation electrode segment 20a. In some cases, the distal portion 90 also includes a discrete tip electrode 36 located distal to the second defibrillation electrode segment 20b. However, the distal portion 90 of the lead body 92 may include more or less of the above-described discrete electrode 34. Figure 1-7 For example, one or more discrete electrodes 34 may be located between defibrillation electrode segments 20.

[0076] In another embodiment, the second defibrillation electrode segment 20b may include more than one coated portion 26 and / or more or less than two uncoated portions 28. For example, the second defibrillation electrode segment 20b may include a single uncoated portion 28 disposed between two coated portions 26. In yet another embodiment, the first defibrillation electrode segment 20a may include the coated and uncoated portions described above, and the second defibrillation electrode segment 20b may be completely coated.

[0077] exist Figure 8 and Fig. 9 In the example shown, all of the uncoated portions 28 of the defibrillation electrode segments 20 (e.g., the uncoated portions 28a and 28a' of segment 20a or the uncoated portions 28b and 28b' of segment 20b) will function together because they are on the same conductive electrode. However, in the case where the defibrillation electrode segments 20a and 20b are coupled to separate conductors, the uncoated portions 28b and 28b' of segment 20b can be used independently of the uncoated portions 28a and 28a' of segment 20a as part of an electrode vector between one or more other electrodes, which can include the housing electrode 33.

[0078] Fig.10Another configuration of the distal portion 100 and the lead body 102 is shown. The lead body 102 may include Figure 1-3 The lead body 12 (and vice versa), Figure 4 lead body 42 (and vice versa), Figure 5 The lead body 52 (and vice versa), Figure 6 lead body 62 (and vice versa), Figure 7 lead body 72 (and vice versa), Figure 8 lead body 82 (or vice versa) and / or Fig. 9 One or more structures and / or functions of the lead body 92 (or vice versa), including size, material, etc. Fig.10 In the example shown, the lead body 102 is substantially conformable to Figure 3 1 , except that the lead body 102 includes an anchoring mechanism 104 and a different configuration of discrete electrodes.

[0079] The anchoring mechanism 104 is a barbed or toothed mechanism configured for attachment to the fascia of tissue proximal to the upper sternal region or below the sternum. However, any anchoring mechanism may be used in place of the anchoring mechanism 104. Alternatively or additionally, the anchoring mechanism 104 may be located at other locations along the lead body 102 and may be secured at one or more locations between the xiphoid process and the upper sternal region. For example, the anchoring mechanism 104 may be located proximal to the first defibrillation electrode segment 20a, such as proximal to the location where the lead transitions from a parasternal position near the xiphoid process to its subcutaneous path laterally along the torso toward the ICD 32 ( Figure 1 ). Another exemplary anchoring mechanism is described in U.S. patent application serial number 14 / 283,278, entitled “IMPLANTABLE MEDICAL DEVICES, SYSTEMS AND COMPONENTS THEREOF” filed on April 28, 2014. In other examples, the distal portion of the lead body 102 may not include any anchoring mechanism 104. One or more anchoring mechanisms 104 of the lead body 102 may be the same or different from each other.

[0080] The distal end portion 100 of the lead body 102 includes discrete electrodes 34a, 34b and 36. These electrodes may include the types, spacings, sizes or other features described in any of the above embodiments. In addition, the coated portion 26 and / or the uncoated portion 28 of the defibrillation electrode segment 20 and / or the discrete electrodes 34a, 34b and 36 and / or the shell electrode 33 (as described above) Figure 1-9 Various electrode vectors formed by the vectors described in can be used to deliver electrical stimulation therapy and / or sense the electrical activity of the heart.

[0081] Although for the sake of brevity Figure 1-10 34 and / or 36 relative to the position of the defibrillation electrode segments 20. For example, electrodes 34a and 34b may be positioned distally of defibrillation electrode segments 20a and 20b, respectively. In all cases, fewer or additional electrodes 34 and / or 36 not depicted may be present distally and / or proximally and / or between defibrillation electrode segments 20 for each example. Figure 1-10 ). In addition, there may be more than two defibrillation electrode segments 20, with any number of electrodes 34 and / or 36 located between, proximal to, and / or distal to any defibrillation electrode segment 20. For example, although in Figure 1-3 No electrodes are located between defibrillation electrode segments 20a and 20b in the illustrated example, but an additional electrode or electrodes may be added between defibrillation electrode segments 20a and 20b, proximal to defibrillation electrode segment 20a, and / or distal to defibrillation electrode segment 20b, while retaining electrodes 34 and 36 as depicted.

[0082] In addition, for all examples provided ( Figure 1-10 ), the number of electrodes 34 or 36 depicted may be reduced. For example, although in Figure 3 In the illustrated example, two electrodes 34 and 36 are shown, but one or both of the electrodes 34 and 36 may not be present. For all embodiments, the types, sizes, shapes, and materials of all electrodes may be the same or different from each other. In addition, the positions of the electrodes 34 and 36 may vary relative to the positions of the uncoated and coated portions 28 and 26 or any added or reduced uncoated and coated portions 28 and 26 not depicted, so that for all possible positions of the electrodes 34 and 36, the uncoated or coated portions 28 and 26 may occur at the distal end, proximal end, middle, or a mixture of the proximal end, distal end, and middle of the defibrillation electrode segment 20.

[0083] exist Figure 1-3 The lead body 12, Figure 4 The lead body 42, Figure 5 The lead body 52, Figure 6 The lead body 62, Figure 7 The lead body 72, Figure 8 The lead body 82 and / or Fig. 9 The lead body 92 and / or Fig.10In an exemplary implantation of the lead body 102 of the embodiment of the present invention, one or more uncoated portions 28 of the first defibrillation electrode segment 20a and / or the second defibrillation electrode segment 20b can be positioned subcutaneously or substernally over any desired chamber or region of the patient's heart. For example, the distal portion of any one of the lead bodies 12, 42, 52, 62, 72, 82, 92, or 102 can be positioned subcutaneously or substernally over the cardiac silhouette, as viewed under anterior-posterior fluoroscopy, such that one or both of the uncoated portions 28 of the defibrillation electrode segments 20 are positioned substantially subcutaneously or substernally over the ventricle or other cardiac target. In one example, the distal portion of any one of the lead bodies 12, 42, 52, 62, 72, 82, 92, or 102 can be positioned subcutaneously or substernally over the cardiac silhouette, as viewed under anterior-posterior fluoroscopy, such that the insulating portion between the defibrillation electrode segments 20 is substantially centered over the ventricle or other cardiac target.

[0084] Therefore, the present disclosure further contemplates a method, the method comprising: making an incision at a first position close to the center of the patient's torso; introducing an implantation tool into the patient's body through the incision at the first position; advancing the distal end of the implantation tool to create a channel; introducing the medical electrical lead into the channel so that the distal portion of the elongated lead body is positioned at any of the above positions. For example, the distal portion of the elongated lead body can be positioned between a first position close to the xiphoid process and a second position above the xiphoid process so that at least one of the multiple defibrillation electrode segments is positioned in front of the heart chamber. In one example, the channel can be a subcutaneous channel passing through subcutaneous tissue and / or muscle above the thoracic cavity. In another example, the channel can be a substernal channel passing through tissue, lymphatic vessels, lymph glands, substernal muscle tissue, or other anatomical structures in the substernal space. In other cases, the channel can be formed by advancing the implantation tool through an incision near the manubrium sternum to form a channel toward the xiphoid process.

[0085] Additionally, unless stated above to the contrary, it should be noted that all of the accompanying drawings are not to scale. In view of the above teaching, numerous modifications and variations are possible without departing from the scope and spirit of the present invention, which is limited only by the following claims.

Claims

1. An implantable medical electrical lead, comprising: an elongated lead body having proximal and distal portions; a first electrode on the distal portion of the elongated lead body, wherein the first electrode comprises: A first section, the first section comprising at least one coated portion, the coated portion being coated with an electrically insulating material, the electrically insulating material being configured to: attenuates the delivery of pacing pulses to the patient's heart; attenuating sensing of electrical activity of the heart via the at least one coated portion; and allowing delivery of a defibrillation shock to the patient's heart, wherein the pacing pulses to be delivered and the electrical activity to be sensed have a voltage amplitude less than the defibrillation shock; as well as a second segment, the second segment being spaced apart from the first segment by a distance, wherein the second segment comprises: at least one coated portion, the at least one coated portion being coated with the electrical insulating material; and at least one uncoated portion, the at least one uncoated portion being configured to: delivering pacing pulses to the patient's heart; and sensing the electrical activity of the heart; wherein the electrically insulating material is configured to attenuate sensing of the electrical activity of the heart through the at least one coated portion as compared to the at least one uncoated portion, a second electrode on the distal portion of the lead body, wherein the second electrode is configured to: delivering one or more pacing pulses to the heart; and The electrical activity of the heart is sensed.

2. The lead wire according to claim 1, characterized in that The electrically insulating material is tantalum pentoxide.

3. The lead wire according to claim 1, characterized in that The second electrode is disposed on the elongated lead body proximal to the first electrode.

4. The lead wire according to claim 1, characterized in that Further included is an electrical conductor disposed within the elongated lead body, wherein the first segment of the first electrode is electrically connected to the electrical conductor, and wherein the second segment of the first electrode is electrically connected to the electrical conductor.

5. The lead wire according to claim 1, characterized in that Further including: a first electrical conductor disposed within the elongated lead body, wherein the first segment of the first electrode is electrically connected to the first electrical conductor; as well as A second electrical conductor is disposed within the elongated lead body, wherein the second segment of the first electrode is electrically connected to the second electrical conductor.

6. The lead wire according to claim 5, characterized in that Further included is a third electrical conductor disposed within the elongated lead body, wherein the second electrode is electrically connected to the third electrical conductor.

7. The lead wire according to claim 1, characterized in that The first segment of the first electrode further includes at least one uncoated portion configured to perform one or more of the following: delivering one or more pacing pulses to the patient's heart; or Electrical activity of the heart is sensed.

8. The lead wire according to claim 7, characterized in that The at least one uncoated portion of the first segment includes one uncoated portion located at a distal end of the first segment, and wherein the at least one coated portion of the first segment includes one coated portion located proximal to the one uncoated portion of the first segment.

9. The lead wire according to claim 1, characterized in that The first segment of the first electrode is disposed on the elongated lead body proximal to the second segment of the first electrode, and wherein the second electrode is disposed on the elongated lead body between the first segment of the first electrode and the second segment of the second electrode.

10. The lead wire according to claim 1, characterized in that wherein the lead further comprises a third electrode on the distal portion of the lead body; wherein the third electrode is configured to perform one or both of the following: delivering one or more pacing pulses to the heart; or sensing the electrical activity of the heart, and The third electrode is disposed on the elongated lead body at a distal end of the second segment of the first electrode.

11. An implantable medical electrical lead, comprising: an elongated lead body having proximal and distal portions; a first electrode on the distal portion of the elongated lead body, wherein the first electrode comprises: A first section, the first section comprising at least one coated portion, the at least one coated portion being coated with an electrically insulating material, the electrically insulating material being configured to: attenuating transmission of one or more electrical signals comprising a voltage amplitude less than a first voltage amplitude value; and allowing transmission of one or more electrical signals comprising a voltage amplitude greater than a second voltage amplitude value; wherein the second voltage amplitude value is greater than or equal to the first voltage amplitude value; and a second segment, the second segment being spaced apart from the first segment by a distance, wherein the second segment comprises: at least one coated portion, the at least one coated portion being coated with the electrical insulating material; and at least one uncoated portion, the at least one uncoated portion configured to allow transmission of one or more electrical signals including a voltage amplitude less than the first voltage amplitude value, wherein the electrically insulating material is configured to attenuate sensing of electrical activity of the heart through the at least one coated portion as compared to the at least one uncoated portion, wherein the electrical activity of the heart includes a voltage amplitude less than the first voltage amplitude value; and A second electrode on the distal portion of the lead body, wherein the second electrode is configured to allow transmission of one or more electrical signals including a voltage amplitude less than the first voltage amplitude value.

12. The lead wire according to claim 11, characterized in that The first voltage amplitude value is in the range of 1 volt (V) to 15V, and the second voltage amplitude value is in the range of 10V to 150V.

13. The lead wire according to claim 11, characterized in that The electrically insulating material is tantalum pentoxide.

14. The lead wire according to claim 11, characterized in that The second electrode is disposed on the elongated lead body proximal to the first electrode.

15. The lead wire according to claim 11, characterized in that Further included is an electrical conductor disposed within the elongated lead body, wherein the first segment of the first electrode is electrically connected to the electrical conductor, and wherein the second segment of the first electrode is electrically connected to the electrical conductor.

16. The lead wire according to claim 11, characterized in that Further including: a first electrical conductor disposed within the elongated lead body, wherein the first segment of the first electrode is electrically connected to the first electrical conductor; as well as A second electrical conductor is disposed within the elongated lead body, wherein the second segment of the first electrode is electrically connected to the second electrical conductor.

17. The lead wire according to claim 16, characterized in that Further included is a third electrical conductor disposed within the elongated lead body, wherein the second electrode is electrically connected to the third electrical conductor.

18. The lead wire according to claim 11, characterized in that The first segment of the first electrode further includes at least one uncoated portion configured to allow transmission of one or more electrical signals including a voltage magnitude less than the first voltage value.

19. The lead wire according to claim 18, characterized in that The at least one uncoated portion of the first segment includes one uncoated portion located at a distal end of the first segment, and wherein the at least one coated portion of the first segment includes one coated portion located proximal to the one uncoated portion of the first segment.

20. The lead wire according to claim 11, characterized in that The first segment of the first electrode is disposed on the elongated lead body proximal to the second segment of the first electrode, and wherein the second electrode is disposed on the elongated lead body between the first segment of the first electrode and the second segment of the first electrode.

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