Cardiac resynchronization therapy with VFA

Abstract

VfA cardiac treatment uses an implantable medical device or system. The implantable medical device includes a tissue puncture electrode, which is implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart through the right atrial endocardium and the central fiber body from the Koch triangle of the right atrium. The device may include a right atrial electrode, a right atrial motion detector, or both. The device may be completely implanted in the patient's heart, or one or more leads may be used to implant the electrode into the patient's heart. The device can be used to provide cardiac treatment, including single-chamber or multi-chamber pacing, atrioventricular synchronous pacing, asynchronous pacing, triggered pacing, cardiac resynchronization pacing, or tachycardia-related treatment. A separate medical device can be used to provide some functions for cardiac treatment, such as sensing, pacing, or electric shock therapy.

Description

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 62 / 647,441, filed on March 23, 2018, which is incorporated herein by reference in its entirety.

[0002] The present disclosure relates to implantable medical devices, systems and methods. In particular, the present disclosure relates to implantable medical devices, systems and methods for ventricle-from-atrium (VfA) cardiac therapy, including single-chamber or multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing), atrioventricular synchronous pacing, asynchronous pacing, triggered pacing, cardiac resynchronization pacing, or tachycardia-related therapy.

[0003] The cardiac conduction system includes the sinoatrial (SA) node, the atrioventricular (AV) node, the His bundle, bundle branches and Purkinje fibers. The heartbeat is initiated in the SA node, which can be described as the natural "pacemaker" of the heart. The electrical impulses caused by the SA node cause the atrial myocardium to contract. The signal is conducted to the ventricle via the AV node, which inherently delays conduction to allow the atrial contraction to stop before the ventricle begins to contract, thereby providing appropriate AV synchronization. The electrical impulses are conducted from the AV node to the ventricular myocardium via the His bundle, bundle branches and Purkinje fibers.

[0004] Patients with conduction system abnormalities (such as AV node malconduction or SA node dysfunction) may receive an implantable medical device (IMD), such as a pacemaker, to restore a more normal heart rhythm and AV synchronization. Some types of IMDs (such as pacemakers, implantable cardioverter-defibrillators (ICDs), or cardiac resynchronization therapy (CRT) devices) provide therapeutic electrical stimulation to the patient's heart via electrodes on one or more implanted endocardial, epicardial, or coronary venous leads positioned in or near the heart. Therapeutic electrical stimulation can be delivered to the heart in the form of pulses or shocks for pacing, cardioversion, or defibrillation. In some cases, the IMD can sense intrinsic depolarization of the heart and control the delivery of therapeutic stimulation to the heart based on this sensing.

[0005] Delivering therapeutic electrical stimulation to the heart can be useful in addressing cardiac conditions such as ventricular dyssynchrony that may occur in a patient. Ventricular dyssynchrony can be described as a lack of synchronization or differences between the contraction timing of the different chambers of the heart. Significant differences in contraction timing can reduce cardiac efficiency. CRT delivered to the heart by an IMD can enhance cardiac output by resynchronizing the electromechanical activity of the heart's ventricles. Because CRT paces the right atrium, right ventricle, and left ventricle, CRT is sometimes referred to as "three-chamber pacing."

[0006] In addition to cardiac pacing, for example, from an ICD, cardiac arrhythmias can also be treated by delivering electric shock therapy to cardiovert or defibrillate the heart, the ICD can sense the patient's cardiac rhythm and classify the rhythm according to an arrhythmia detection scheme to facilitate detection of the onset of tachycardia or fibrillation. The detected arrhythmias may include ventricular tachycardia (VT), rapid ventricular tachycardia (FVT), ventricular fibrillation (VF), atrial tachycardia (AT) and atrial fibrillation (AT). Anti-tachycardia pacing (ATP) is a painless treatment that can be used to treat ventricular tachycardia (VT) to essentially terminate many monomorphic rapid rhythms. Although ATP is painless, ATP may not deliver effective treatment for all types of VT. For example, ATP may not be as effective for polymorphic VT with various morphologies. Polymorphic VT and ventricular fibrillation (VF) may be more fatal and may require more rapid treatment by electric shock.

[0007] Dual chamber medical devices are available that include a transvenous atrial lead that carries an electrode that can be placed in the right atrium and a transvenous ventricular lead that carries an electrode that can be placed in the right ventricle via the right atrium. The dual chamber medical device itself is typically implanted in a subcutaneous pocket, and the transvenous lead is tunneled to the subcutaneous pocket. The dual chamber medical device can sense atrial electrical signals as well as ventricular electrical signals, and can provide both atrial pacing and ventricular pacing as needed to promote normal heart rhythm and AV synchronization. Some dual chamber medical devices can treat both atrial and ventricular arrhythmias.

[0008] It has been introduced or proposed to implant intracardiac medical devices (such as leadless pacemakers) completely within the patient's heart, thereby eliminating the need for transvenous leads. The leadless pacemaker may include one or more electrodes on its external housing to deliver therapeutic electrical signals and / or sense intrinsic depolarization of the heart. The intracardiac medical device may provide cardiac therapy functions (such as sensing and pacing) within a single chamber of the patient's heart. Single-chamber intracardiac devices may also treat atrial arrhythmias or ventricular arrhythmias or atrial fibrillation or ventricular fibrillation. Some leadless pacemakers are not intracardiac and may be located outside the heart, and in some examples, may be anchored to the wall of the heart via a fixation mechanism.

[0009] In some patients, a single chamber device may adequately address the patient's needs. However, a single chamber device capable of only single chamber sensing and therapy may not fully address cardiac conduction disease or abnormalities in all patients, for example, those with some forms of AV dyssynchrony or tachycardia. In some cases, dual chamber sensing and / or pacing capabilities may be used in addition to ICD functionality to restore a more normal heart rhythm. Summary of the invention

[0010] Various embodiments of the present disclosure relate to implantable medical devices, systems and methods for VfA cardiac therapy, including single-chamber or multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing), atrioventricular synchronous pacing, asynchronous pacing, triggered pacing, cardiac resynchronization pacing or tachycardia-related therapy. Tissue puncture electrodes are implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to facilitate VfA cardiac therapy.

[0011] In one aspect, the present disclosure relates to an implantable medical device comprising a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle and sensing at least one of the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode positionable within the right atrium for delivering cardiac therapy and sensing at least one of the electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the electrical activity of the right atrium using the right atrial electrode; and deliver atrioventricular synchronous pacing based on the monitored electrical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0012] On the other hand, the present disclosure relates to a method comprising: monitoring the activity of the right atrium of a patient's heart using a right atrial electrode or a right atrial motion detector; and delivering atrioventricular synchronous pacing based on the monitored electrical activity of the right atrium using at least a tissue puncture electrode implanted in the basal and / or septal regions of the left ventricular myocardium of the patient's heart from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body, including pacing one or both ventricles using at least the at least one tissue puncture electrode.

[0013] On the other hand, the present disclosure relates to an implantable medical device, which includes a shell extending from a proximal end region to a distal end region. The device also includes a plurality of electrodes. The plurality of electrodes include a tissue puncture electrode, which is leadless coupled to the distal end region of the shell and is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body, for delivering cardiac therapy to the left ventricle or sensing the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode that is leadless coupled to the shell and positionable in the right atrium, for delivering cardiac therapy to the right atrium of the patient's heart or sensing the electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit in the shell, which is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit in the shell, which is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller including a processing circuit system operably coupled to the therapy delivery circuit and the sensing circuit within the housing. The controller is configured to: monitor the electrical activity of the right atrium using the right atrial electrode; and deliver atrioventricular synchronous pacing based on the monitored electrical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0014] In another aspect, the present disclosure relates to an implantable medical device comprising a plurality of electrodes. The plurality of electrodes comprises a tissue piercing electrode implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle and sensing at least one of the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The tissue piercing electrode also comprises a right atrial motion detector positionable within the right atrium for sensing the mechanical activity of the right atrium of the patient's heart. The implantable medical device also comprises: a therapy delivery circuit operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further comprises a controller comprising a processing circuit system operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the mechanical activity of the right atrium using a right atrial motion detector; and deliver atrioventricular synchronous pacing based on the monitored mechanical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0015] In another aspect, the present disclosure relates to an implantable medical device comprising a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle or sensing at least one of the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing at least one of the electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to monitor the electrical activity of the right atrium using a right atrial electrode and monitor the electrical activity of the left ventricle using a tissue piercing electrode implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body. The controller is also configured to deliver cardiac resynchronization pacing based on the monitored electrical activity using at least a tissue piercing electrode implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart through the right atrial endocardium and the central fibrous body to pace one or both ventricles.

[0016] In another aspect, the present disclosure relates to a method comprising at least one of the following: monitoring electrical activity of the right atrium of a patient's heart using a right atrial electrode; and monitoring electrical activity of the left ventricle using a tissue piercing electrode implanted in a basal region and / or septal region of the left ventricular myocardium of the patient's heart from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body. The method also includes delivering cardiac resynchronization pacing, including pacing one or both ventricles, based on the monitored electrical activity using at least a tissue piercing electrode implanted in a basal region and / or septal region of the left ventricular myocardium of the patient's heart from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body.

[0017] On the other hand, the present disclosure relates to an implantable medical device, which includes a shell extending from a proximal end region to a distal end region. The implantable medical device also includes a plurality of electrodes. The plurality of electrodes include a tissue puncture electrode, which is leadless coupled to the distal end region of the shell and is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body, for delivering cardiac therapy to the left ventricle or sensing the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode that is leadless coupled to the shell and positionable in the right atrium, for delivering cardiac therapy to the right atrium of the patient's heart or sensing the electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit in the shell, which is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit in the shell, which is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller, which includes a processing circuit system within the housing that is operably coupled to the treatment delivery circuit and the sensing circuit. The controller is configured for at least one of the following: monitoring electrical activity of the right atrium using a right atrial electrode; and, monitoring electrical activity of the left ventricle using a tissue puncture electrode that passes from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body and in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The controller is further configured to deliver cardiac resynchronization pacing based on the monitored electrical activity using at least a tissue puncture electrode that is implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0018] In another aspect, the present disclosure relates to an implantable medical device comprising a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle and sensing at least one of the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial motion detector that can be positioned within the right atrium for sensing the mechanical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the mechanical activity of the right atrium using a right atrial motion detector; and deliver cardiac resynchronization pacing based on the monitored mechanical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0019] On the other hand, the present disclosure relates to an implantable medical device comprising a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the electrical activity of the right atrium using a right atrial electrode; monitor the electrical activity of the left ventricle using a tissue-piercing electrode, which is implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to sense the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium; and deliver tachycardia therapy based on the monitored electrical activity of the right atrium and left ventricle.

[0020] On the other hand, the present disclosure relates to a method, comprising: monitoring the electrical activity of the right atrium of a patient's heart using a right atrial electrode; monitoring the electrical activity of the left ventricle of the patient's heart using a tissue-piercing electrode, the tissue-piercing electrode being implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body into the basal region and / or septal region of the left ventricular myocardium of the patient's heart to sense the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium; and delivering tachycardia treatment based on the monitored electrical activity of the right atrium and left ventricle.

[0021] On the other hand, the present disclosure relates to an implantable medical device comprising a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the electrical activity of the right atrium using a right atrial electrode; monitor the electrical activity of the left ventricle using a tissue-piercing electrode, which is implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal area and / or septal area of ​​the left ventricular myocardium of the patient's heart to sense the electrical activity of the left ventricle; and determine tachycardia of the patient's heart based on the monitored right atrial and left ventricular electrical activities.

[0022] On the other hand, the present disclosure relates to an implantable medical device comprising a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to at least one of: deliver anti-tachycardia pacing therapy using the plurality of electrodes and deliver shock therapy using a separate medical device.

[0023] The above summary of the invention is not intended to describe every embodiment or every implementation of the present disclosure. A more complete understanding will become apparent and understandable by reference to the following detailed description obtained in conjunction with the accompanying drawings and the claims. In other words, these and various other features and advantages will become apparent by reading the detailed description below. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a conceptual diagram of an illustrative cardiac treatment system including an intracardiac medical device implanted in a patient's heart shown in a cross-sectional view and a separate medical device positioned outside the patient's heart.

[0025] Figure 2 yes Figure 1 Conceptual illustration of intracardiac medical equipment and a magnified anatomical structure of a patient's heart.

[0026] Figure 3 A distal fixation and electrode assembly having a distal housing-based electrode implemented as a ring electrode Figure 1-Figure 2 Perspective view of intracardiac medical equipment.

[0027] Figure 4 Can be enclosed in Figure 1-Figure 3 00136] A block diagram of an exemplary circuit system within the housing of an intracardiac medical device, for example, for providing the functions and treatments described herein.

[0028] Figure 5 is used with, for example Figure 1-Figure 4 A perspective view of another illustrative intracardiac medical device for use with the illustrative systems and devices of FIG.

[0029] Figure 6 is used with, for example Figure 1-Figure 5 A flow chart of an illustrative cardiac treatment method for use with an illustrative system and device.

[0030] Figure 7 is used with, for example Figure 6 A flowchart of an illustrative pacing therapy method used in conjunction with an illustrative method.

[0031] Figure 8 is used with, for example Figure 6 A flow chart of another illustrative pacing therapy method for use in conjunction with the illustrative method of.

[0032] Fig. 9 is used with, for example Figure 1-Figure 5 A flow chart of an illustrative tachycardia-related method for use with an illustrative system and device.

[0033] Fig.10 is used with, for example Fig. 9 A flow chart of an illustrative tachycardia determination method for use with the illustrative method.

[0034] Fig.11 is used with, for example Fig.10 A flow chart of an illustrative tachycardia treatment determination method for use with the illustrative method.

[0035] Fig.12 is used with, for example Figure 1-Figure 5 A flow chart of another illustrative anti-tachycardia method for use with an illustrative system and device.

[0036] Fig.13 is used with, for example Fig.12 An illustrative method is used together with a flow chart of an illustrative tachycardia therapy delivery method.

[0037] Fig.14 is used with, for example Fig.13 A flow chart of an illustrative electric shock therapy method used in conjunction with an illustrative method.

[0038] Fig.15 is shown for example Figure 1-Figure 5 A conceptual diagram of an exemplary system and device together with a diagram of a patient's heart with a standard 17-segment view of the left ventricle using various electrode implant locations.

[0039] Figure 16-18 is a conceptual diagram of an illustrative cardiac treatment system including a medical device including a lead having a catheter implanted in the heart of a patient shown in cross-sectional view for communicating with, for example, Figure 6-Figure 14 An illustrative approach or Figure 1-Figure 5Electrodes for use with illustrative systems and devices.

[0040] Fig.19 is shown for example Figure 1-Figure 5 and Figure 16-18 State diagrams of different illustrative modes for use with an illustrative system and device.

[0041] Fig. 20 is included for example Figure 1-Figure 5 and Figure 16-18 Diagram of an illustrative system of electrode devices, display devices, and computing devices for use with illustrative systems and devices.

[0042] Figure 21-22 is used with, for example Figure 1-Figure 5 and Figure 16-18 A diagram of an illustrative in vitro electrode arrangement for measuring electrical potentials on the surface of the torso for use with an illustrative system and apparatus.

[0043] Fig.23 is used with, for example Figure 1-Figure 5 and Figure 16-18 A flowchart of an illustrative method for using an atrial motion detector to detect atrial activity is provided in conjunction with an illustrative system and apparatus. DETAILED DESCRIPTION

[0044] The present disclosure relates to implantable medical devices, systems and methods for VfA cardiac treatment, including single-chamber or multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing), atrioventricular synchronous pacing, asynchronous pacing, triggered pacing, cardiac resynchronization pacing or tachycardia-related treatment. Although reference is made herein to implantable medical devices, such as pacemakers or ICDs, these methods and processes may be used with any medical device, system or method related to a patient's heart. Various other applications will be apparent to those skilled in the art having the benefit of this disclosure.

[0045] It may be beneficial to provide an implantable medical device without a transvenous lead (e.g., a leadless device). It may also be beneficial to provide an implantable medical device that can be used for various cardiac therapies, such as single-chamber or multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing), atrioventricular synchronous pacing, asynchronous pacing, triggered pacing, cardiac resynchronization pacing, or tachycardia-related therapy. Further, it may be beneficial to provide a system that can communicate with a separate medical device, for example, to provide triggered pacing or to provide shock therapy in certain cases of tachycardia.

[0046] The present disclosure provides an implantable medical device including a tissue puncture electrode and optionally including a right atrial electrode and / or a right atrial motion detector. The tissue puncture electrode can be implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart through the right atrial endocardium and the central fiber body from the Koch triangle of the right atrium. In a leadless implantable medical device, the tissue puncture electrode can extend from the distal end region of the housing of the device without a lead, and the right atrial electrode can be coupled to the housing without a lead (e.g., as part of the housing or positioned on the outside of the housing). The right atrial motion detector can be in the implantable medical device. In a leaded implantable medical device, one or more of the electrodes can be coupled to the housing using an implantable lead. When the device is implanted, the electrode can be used to sense electrical activity in one or more atria and / or ventricles of the patient's heart. The motion detector can be used to sense mechanical activity in one or more atria and / or ventricles of the patient's heart. Specifically, the activity of the right atrium and left ventricle can be monitored, and the activity of the right ventricle can be optionally monitored. The electrodes can be used to deliver cardiac therapy, such as single chamber pacing for atrial fibrillation, atrioventricular synchronous pacing for bradycardia, asynchronous pacing, triggered pacing, cardiac resynchronization pacing for treating ventricular asynchrony, anti-tachycardia pacing, or electric shock therapy. Electric shock therapy can be initiated by an implantable medical device. A separate medical device (such as an extravascular ICD) can also be implanted, which can communicate operatively with the implantable medical device and can deliver an electric shock in response to a trigger (such as a signaling pulse (e.g., a trigger, signaling, or a unique electrical pulse) provided by the device).

[0047] Reference will now be made to the accompanying drawings, which depict one or more aspects described in the present disclosure. However, it will be understood that other aspects not depicted in the accompanying drawings will fall within the scope of the present disclosure. The same reference numerals in the accompanying drawings refer to the same parts, steps, etc. However, it will be understood that the use of reference numerals to refer to elements in a given figure is not intended to limit the elements in another figure labeled with the same reference numeral. In addition, the use of different reference numerals to refer to elements in different figures is not intended to indicate that the differently labeled elements cannot be the same or similar.

[0048] Although the present disclosure describes both leadless and leaded implantable medical devices, reference is first made to Figure 1, shows a conceptual diagram of a cardiac treatment system 2 including an intracardiac medical device 10 that can be configured for single-chamber or dual-chamber treatment and implanted in a patient's heart 8. In some embodiments, the device 10 can be configured for single-chamber pacing and can, for example, switch between single-chamber and multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing). As used herein, "intracardiac" refers to a device that is configured to be completely implanted within a patient's heart, for example, to provide cardiac treatment. The device 10 is shown implanted in the right atrium (RA) of the patient's heart 8 in a target implant area 4. The device 10 may include one or more fixation members 20 that anchor the distal end of the device against the atrial endocardium in the target implant area 4. The target implant area 4 may be located between the His bundle 5 and the coronary sinus 3, and may be adjacent to the tricuspid valve 6. Device 10 may be described as an atrium-to-ventricle (VfA) device that may sense or provide therapy to one or more ventricles (e.g., the right ventricle, the left ventricle, or both ventricles, as the case may be) while being disposed generally in the right atrium. Specifically, device 10 may include a tissue-penetrating electrode that may be implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body into the basal and / or septal regions of the left ventricular myocardium of the patient's heart.

[0049] The device 10 can be described as a leadless implantable medical device. As used herein, "leadless" refers to a device that has no leads extending outward from the patient's heart 8. In other words, a leadless device may have leads that do not extend from outside the patient's heart to inside the patient's heart. Some leadless devices can be introduced intravenously, but once implanted, the device does not have or may not include any transvenous leads, and may be configured to provide cardiac therapy without the use of any transvenous leads. When the housing of the leadless VfA device is positioned in the atrium, the device, in particular, does not use leads to be operably connected to electrodes in the ventricle. The leadless electrodes can be coupled to the housing of the medical device without the use of leads between the electrodes and the housing.

[0050] The device 10 may include one or more dart electrodes 12 having a straight shaft extending from a distal end region of the device 10, through the atrial myocardium and the central fiber body, and into the ventricular myocardium 14 or extending along the ventricular septum without completely penetrating the ventricular endocardial or epicardial surface. That is, the dart electrode 12 may not puncture through the ventricular wall into the blood volume. The dart electrode 12 may carry an electrode at the distal end region of the shaft to position the electrode within the ventricular myocardium for sensing ventricular signals and delivering ventricular pulses (e.g., for depolarizing the left ventricle to initiate contraction of the left ventricle). In some examples, the electrode at the distal end region of the shaft is a cathode electrode provided for use in a bipolar electrode pair for pacing and sensing. Although in Figure 1Implantation region 4 is shown to enable one or more of one or more dart electrodes 12 to be positioned in the ventricular myocardium, but it is recognized that devices having aspects disclosed herein may be implanted at other locations for multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing), single-chamber pacing with multi-chamber sensing, single-chamber pacing and / or sensing, or other clinical treatments and applications, as applicable.

[0051] The cardiac treatment system 2 may also include a separate medical device 50 (in Figure 1 ), which can be positioned outside the patient's heart 8 (e.g., subcutaneously) and can be operably coupled to the patient's heart 8 for delivering cardiac therapy to the heart 8. In one example, the separate medical device 50 can be an extravascular ICD. In some embodiments, the extravascular ICD may include a defibrillation lead with a defibrillation electrode. The therapy vector may exist between the defibrillation electrode on the defibrillation lead and the housing electrode of the ICD. Further, one or more electrodes of the ICD may also be used to sense electrical signals related to the patient's heart 8. The ICD may be configured to deliver electrical shock therapy including one or more defibrillation or cardioversion shocks. For example, if an arrhythmia is sensed, the ICD may send pulses via electrical leads to shock the heart and restore its normal rhythm. In some examples, the ICD can deliver electrical shock therapy without placing electrical leads in the heart or attaching electrical leads directly to the heart (subcutaneous ICD). An example of an extravascular, subcutaneous ICD described herein that may be used with the system 2 may be described in U.S. Patent No. 9,278,229 (Reinke et al.), issued on March 8, 2016, which is incorporated herein by reference in its entirety.

[0052] In the case of shock therapy, for example, a defibrillation shock provided by a defibrillation electrode of a defibrillation lead, a separate medical device 50 (e.g., an extravascular ICD) may include a control circuit that uses a therapy delivery circuit to generate a defibrillation shock having any of a plurality of waveform attributes, including leading-edge voltage, tilt, delivered energy, pulse phase, etc. The therapy delivery circuit may, for example, generate a monophasic, biphasic, or multiphasic waveform. Additionally, the therapy delivery circuit may generate a defibrillation waveform having different amounts of energy. For example, the therapy delivery circuit may generate a defibrillation waveform that delivers a total of between approximately 60-80 joules (J) of subcutaneous defibrillation energy.

[0053] The separate medical device 50 may include a sensing circuit. The sensing circuit may be configured to acquire electrical signals sensed via one or more combinations of electrodes and process the acquired signals. The components of the sensing circuit may be analog components, digital components, or a combination thereof. The sensing circuit may, for example, include one or more sensing amplifiers, filters, rectifiers, threshold detectors, analog-to-digital converters (ADCs), etc. The sensing circuit may convert the sensed signal to a digital form and provide the digital signal to the control circuit for processing or analysis. For example, the sensing circuit may amplify the signal from the sensing electrode, and the amplified signal may be converted into a multi-bit digital signal by the ADC. The sensing circuit may also compare the processed signal with a threshold value to detect the presence of atrial or ventricular depolarization (e.g., P wave or R wave), and indicate the presence of atrial depolarization (e.g., P wave) or ventricular depolarization (e.g., R wave) to the control circuit.

[0054] The device 10 and the separate medical device 50 can cooperate to provide cardiac therapy to the patient's heart 8. For example, the device 10 and the separate medical device 50 can be used to detect tachycardia, monitor tachycardia, and / or provide tachycardia-related therapy. For example, the device 10 can communicate wirelessly with the separate medical device 50 to trigger an electric shock therapy using the separate medical device 50. As used herein, "wirelessly" refers to an operational coupling or connection without the use of metallic conductors between the device 10 and the separate medical device 50. In one example, wireless communication can use a unique signaling or triggering electrical pulse provided by the device 10 that is conducted through the patient's tissue and detectable by the separate medical device 50. In another example, wireless communication can use a communication interface (e.g., an antenna) of the device 10 to provide electromagnetic radiation that propagates through the patient's tissue and can be detected, for example, using a communication interface (e.g., an antenna) of the separate medical device 50.

[0055] Figure 2 is an enlarged conceptual illustration of an intracardiac medical device 10 and the anatomy of a patient's heart 8. The intracardiac device 10 may include a housing 30. The housing 30 may define an airtight sealed interior cavity in which the internal components of the device 10 reside, such as sensing circuitry, therapy delivery circuitry, control circuitry, memory, telemetry circuitry, other optional sensors, and a power source, as described below in conjunction with Figure 4 The housing 30 may be formed of a conductive material, including titanium or titanium alloys, stainless steel, MP35N (a non-magnetic nickel-cobalt-chromium-molybdenum alloy), platinum alloys, or other biocompatible metals or metal alloys. In other examples, the housing 30 may be formed of a non-conductive material, including ceramic, glass, sapphire, silicone, polyurethane, epoxy, acetyl copolymer plastic, polyetheretherketone (PEEK), liquid crystal polymer, or other biocompatible polymers.

[0056] The housing 30 can be described as extending between a distal end region 32 and a proximal end region 34, generally cylindrical, to facilitate catheter delivery. In other embodiments, the housing 30 can be prism-shaped or any other shape to facilitate the functions and utilities described herein. The housing 30 can include, for example, a delivery tool interface member 26 at the proximal end 34 for engaging with a delivery tool during implantation of the device 10.

[0057] During cardiac therapy, for example, during sensing and / or pacing, all or a portion of the housing 30 may be used as an electrode. In the example shown, the housing-based electrode 24 is shown as circumscribing the proximal portion of the housing 30. When the housing 30 is formed of a conductive material (such as a titanium alloy or other examples listed above), various portions of the housing 30 are electrically insulated by a non-conductive material (such as a coating of parylene, polyurethane, silicone, epoxy, or other biocompatible polymers), leaving one or more discrete areas of the conductive material exposed to define the proximal housing-based electrode 24. When the housing 30 is formed of a non-conductive material (such as a ceramic, glass, or polymer material), a conductive coating or layer (such as titanium, platinum, stainless steel, or alloys thereof) may be applied to one or more discrete areas of the housing 30 to form the proximal housing-based electrode 24. In other examples, the proximal housing-based electrode 24 may be a component mounted or assembled on the housing 30, such as a ring electrode. The proximal housing-based electrode 24 may be electrically coupled to the internal circuitry of the device 10, for example, via the conductive housing 30, or via electrical conductors when the housing 30 is a non-conductive material.

[0058] In the example shown, the proximal shell-based electrode 24 is positioned closer to the shell proximal end region 34 than to the distal end region 32, and is therefore referred to as a "proximal shell-based electrode" 24. However, in other examples, the shell-based electrode 24 may be positioned at other locations along the shell 30, for example, at a relatively more distal location than shown.

[0059] At the distal end region 32, the device 10 may include a distal fixation and electrode assembly 36, which may include one or more fixation members 20 in addition to one or more dart electrodes 12 of equal or unequal lengths. The dart electrode 12 may include a shaft 40 extending distally away from the housing distal end region 32, and may include one or more electrode elements, such as a tip electrode 42 at or near the free distal end region of the shaft 40. The tip electrode 42 may have a conical or hemispherical distal tip with a relatively narrow tip diameter (e.g., less than about 1 mm) for piercing and passing through tissue layers without the use of a sharp tip or a needle tip with a sharp or beveled edge.

[0060] The shaft 40 of the dart electrode 12 can be a normally straight member and can be rigid. In other embodiments, the shaft 40 can be described as being relatively rigid, but still having limited flexibility in the lateral direction. Further, the shaft 40 can be non-rigid to allow some lateral bending with heart movement. However, in a relaxed state, when not subjected to any external force, the shaft 40 can maintain a straight position as shown to keep the tip electrode 42 spaced apart from the distal end region 32 of the housing by at least the height 47 of the shaft 40. The dart electrode 12 can be configured to puncture through one or more tissue layers to position the tip electrode 42 in a desired tissue layer (e.g., ventricular myocardium). Therefore, the height 47 of the shaft 40 can correspond to the desired pacing site depth, and the shaft can have a relatively high compressive strength along its longitudinal axis to resist bending in the lateral or radial direction when pressed against the implantation area 4. If a second dart electrode 12 is used, its length may not be equal to the desired pacing site depth, and can be configured to act as a neutral electrode for delivering pacing energy to the tissue. A longitudinal axial force may be applied to the tip electrode 42, for example, by applying a longitudinal thrust to the proximal end 34 of the housing 30, to advance the dart electrode 12 into tissue within the target implantation area. The shaft 40 may be longitudinally non-compressible. The shaft 40 may be elastically deformable in the lateral or radial direction to allow temporary bending (e.g., with tissue movement) when subjected to lateral or radial forces, but may return to its normal straight position when the lateral forces disappear. The shaft 40 may maintain a straight linear position as shown when the shaft 40 is not exposed to any external forces, or is only exposed to forces along its longitudinal center axis.

[0061] One or more fixation members 20 may be described as one or more "tines" having a normally bent position. These tines may be maintained in a distally extending position within the delivery tool. The distal tips of the tines may penetrate the cardiac tissue to a limited depth before elastically bending back proximally to the normally bent position (shown) after release from the delivery tool. Further, the fixation member 20 may include, for example, one or more aspects described in U.S. Pat. No. 9,675,579 (Grubac et al.), issued on June 13, 2017, and U.S. Pat. No. 9,119,959 (Rys et al.), issued on September 1, 2015, each of which is incorporated herein by reference in its entirety.

[0062] In some examples, the distal fixation and electrode assembly 36 includes a distal shell-based electrode 22. In the case of using the device 10 as a pacemaker for multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing) and sensing, the tip electrode 42 can be used as a cathode electrode that is paired with the proximal shell-based electrode 24 that acts as a return anode electrode. Alternatively, the distal shell-based electrode 22 can act as a return anode electrode paired with the tip electrode 42 for sensing ventricular signals and delivering ventricular pacing pulses. In other examples, the distal shell-based electrode 22 can be a cathode electrode for sensing atrial signals and delivering pacing pulses to the atrial myocardium in the target implant area 4. When the distal shell-based electrode 22 acts as an atrial cathode electrode, the proximal shell-based electrode 24 can act as a return anode paired with the tip electrode 42 for ventricular pacing and sensing, and can act as a return anode paired with the distal shell-based electrode 22 for atrial pacing and sensing.

[0063] As shown in this illustration, the target implantation area 4 in some pacing applications is along the atrial endocardium 18, typically below the AV node 15 and the bundle of His 5. The dart electrode 42 can define a height 47 of the shaft 40 for penetrating through the atrial endocardium 18 in the target implantation area 4, through the central fiber body 16 and into the ventricular myocardium 14 without penetrating through the ventricular endocardial surface 17. When the height 47 of the dart electrode 12 is fully advanced into the target implantation area 4, the tip electrode 42 can be located within the ventricular myocardium 14, and the distal housing-based electrode 22 can be positioned in close contact with or in close proximity to the atrial endocardium 18. The dart electrode 12 can have a total combined height 47 of the tip electrode 42 and the shaft 40, which is about 3 mm to about 8 mm in various examples. The diameter of the shaft 40 can be less than about 2 mm, and can be about 1 mm or less, or even about 0.6 mm or less.

[0064] The device 10 may include a motion detector 11 within the housing 30. The motion detector 11 may be used to monitor mechanical activity, such as atrial mechanical activity (e.g., atrial contraction) and / or ventricular mechanical activity (e.g., ventricular contraction). In some embodiments, the motion sensor 11 may be used to detect right atrial mechanical activity. Non-limiting examples of the motion detector 11 include an accelerometer. In some embodiments, the mechanical activity detected by the motion detector 11 may be used to supplement or replace the electrical activity detected by one or more of the electrodes of the device 10. For example, the motion detector 11 may be used in addition to the proximal housing-based electrodes 24, or the motion detector 11 may be used as a replacement for the proximal housing-based electrodes 24.

[0065] The motion detector 11 may also be used for frequency response detection or for providing a frequency response IMD. Various techniques for frequency response may be described in U.S. Pat. No. 5,154,170 (Bennett et al.), entitled “Optimization for rate responsive cardiac pacemaker,” issued Oct. 13, 1992, and U.S. Pat. No. 5,562,711, entitled “Method and apparatus for rate-responsive cardiac pacing,” issued Oct. 8, 1996, each of which is incorporated herein by reference in its entirety.

[0066] Figure 3 3 is a perspective view of a device 10 capable of performing cardiac treatment. As shown, the distal fixation and electrode assembly 36 includes a distal housing-based electrode 22 implemented as a ring electrode. When the fixation member tines 20a, 20b and 20c of the fixation member 20 engage with the atrial tissue, the distal housing-based electrode 22 can be positioned in close contact with the atrial tissue or operably adjacent to the atrial tissue. The elastically deformable tines 20a, 20b and 20c can extend distally during the delivery of the device 10 to the implantation site. For example, when the device 10 is pushed out of the delivery tool and when it is no longer constrained in the delivery tool, the tines 20a, 20b and 20c can puncture the atrial endocardial surface. When the tines 20a, 20b and 20c bend back to their normal position, the fixation member 20 can pull the distal fixation member and electrode assembly 36 toward the atrial endocardial surface. As the distal fixation member and electrode assembly 36 are pulled toward the atrial endocardium, the tip electrode 42 may be advanced through the atrial myocardium and the central fiber body and into the ventricular myocardium. The distal housing-based electrode 22 may then be positioned against the atrial endocardial surface.

[0067] The distal shell-based electrode 22 may include a ring formed of a conductive material, such as titanium, platinum, iridium, or alloys thereof. The distal shell-based electrode 22 may be a single continuous ring electrode. In other examples, portions of the ring may be coated with an electrically insulating coating, such as parylene, polyurethane, silicone, epoxy, or other insulating coating, to reduce the conductive surface area of ​​the ring electrode. For example, one or more sectors of the ring may be coated to separate two or more conductive exposed surface areas of the distal shell-based electrode 22. Reducing the conductive surface area of ​​the distal shell-based electrode 22 (e.g., by covering portions of the conductive ring with an insulating coating) may increase the electrical impedance of the distal shell-based electrode 22, and thereby reduce the current delivered to capture myocardium (e.g., atrial myocardial tissue) during a pacing pulse. Lower current consumption may conserve a power source of the device 10, such as one or more rechargeable or non-rechargeable batteries.

[0068] As described above, the distal shell-based electrode 22 can be configured as a ventricular cathode electrode for delivering pacing pulses to atrial tissue at the implant site in combination with the proximal shell-based electrode 24 as a return anode. The electrodes 22 and 24 can be used to sense atrial P waves for use in controlling atrial pacing pulses (delivered without a sensed P wave), and for controlling atrial-synchronized ventricular pacing pulses that are delivered using the tip electrode 42 as a cathode and the proximal shell-based electrode 24 as a return anode. In other examples, the distal shell-based electrode 22 can be used as a return anode in combination with the cathode tip electrode 42 for ventricular pacing and sensing.

[0069] Figure 4 According to an example, it can be enclosed in the housing 30 ( Figure 3 ) is a block diagram of a circuit system for providing cardiac treatment functions using device 10. Separate medical device 50 ( Figure 1 ) may include some or all of the same components, which may be configured in a similar manner. The electronic circuit system enclosed within the housing 30 may include software, firmware, and hardware that cooperatively monitor atrial and ventricular electrical cardiac signals, determine when cardiac therapy is necessary, and / or deliver electrical pulses to the patient's heart according to programmed pacing modes and pulse control parameters. The electronic circuit system may include control circuitry 80 (e.g., including processing circuitry), memory 82, therapy delivery circuitry 84, sensing circuitry 86, and / or telemetry circuitry 88. In some examples, the device 10 includes one or more sensors 90 for generating signals related to a patient's physiological function, state, or condition, such as a patient activity sensor, for use in determining the need for pacing therapy and / or controlling the pacing rate.

[0070] The power supply 98 can provide power to the circuit system of the device 10 (including each of the components 80, 82, 84, 86, 88 and 90) as needed. The power supply 98 can include one or more energy storage devices, such as one or more rechargeable or non-rechargeable batteries. The connection between the power supply 98 and each of the components 80, 82, 84, 86 and 88 will be understood from the overall block diagram, but is not shown for clarity. For example, the power supply 98 can be coupled to one or more charging circuits included in the therapy delivery circuit 84 to provide the required power to the charge holding capacitor included in the therapy delivery circuit 84, which is discharged at the appropriate time under the control of the control circuit 80 for, for example, delivering pacing pulses according to a dual-chamber pacing mode such as DDI (R). The power supply 98 can also be coupled to components of the sensing circuit 86 (such as, sense amplifiers, analog-to-digital converters, switching circuit systems, etc.), sensors 90, telemetry circuits 88, and memory 82 to provide power to various circuits.

[0071] Any suitable technique may be used to recharge the rechargeable power source 98. In some embodiments, the device 10 may include an antenna, an inductive coil, or other inductive coupling structure configured to couple to another device (such as an external charger or programmer) for receiving power in situ. Various examples of charging leadless implantable medical devices are described in U.S. Patent Publication No. 2018 / 0212451 (Schmidt et al.), entitled “Recharge of Implanted Medical Devices,” filed on January 26, 2017, which is incorporated herein by reference in its entirety. The device 10 may also be configured to extend the life of the power source 98 using various techniques (such as a low power mode).

[0072] Various examples of power supplies and various techniques related to power supplies may be used, such as those found in, for example, U.S. Patent No. 8,383,269 (Scott et al.), issued on February 26, 2013, U.S. Patent No. 8,105,714 (Schmidt et al.), issued on January 31, 2012, and U.S. Patent No. 7,635,541 (Scott et al.), issued on December 22, 2009, which are incorporated herein by reference in their entirety.

[0073] The functional blocks shown represent the functions included in the device 10, and may include any discrete and / or integrated electronic circuit components that implement analog and / or digital circuits capable of producing the functions attributed to the medical device 10 herein. Various components may include processing circuit systems, such as application specific integrated circuits (ASICs), electronic circuits, processors (shared, dedicated, or groups) and memories that execute one or more software or firmware programs, combinational logic circuits, state machines, or other suitable components or combinations of components that provide the described functions. The specific form of software, hardware, and / or firmware that is adopted to implement the functions disclosed herein will be determined primarily by the specific system architecture adopted in the medical device and the specific detection and treatment delivery methods adopted by the medical device. In view of the disclosure herein, it is within the capabilities of those skilled in the art to provide software, hardware, and / or firmware in the context of any modern cardiac medical device system to perform the described functions.

[0074] Memory 82 may include any volatile, nonvolatile, magnetic, or electrical non-transitory computer-readable storage medium, such as random access memory (RAM), read-only memory (ROM), nonvolatile RAM (NVRAM), electrically erasable programmable ROM (EEPROM), flash memory, or any other memory device. In addition, memory 82 may include a non-transitory computer-readable medium storing instructions that, when executed by one or more processing circuits, cause control circuit 80 and / or other processing circuit systems to perform single-chamber, dual-chamber, or triple-chamber pacing (e.g., single-chamber or multi-chamber pacing) functions or other sensing and therapy delivery functions attributed to device 10. The non-transitory computer-readable medium storing instructions may include any of the media listed above.

[0075] The control circuit 80 may communicate, for example, via a data bus, with a therapy delivery circuit 84 and a sensing circuit 86 for sensing cardiac electrical signals and controlling the delivery of cardiac electrical stimulation therapy in response to sensed cardiac events (e.g., P waves and R waves, or lack thereof). The tip electrode 42, the distal shell-based electrode 22, and the proximal shell-based electrode 24 may be electrically coupled to the therapy delivery circuit 84 for delivering electrical stimulation pulses to the patient's heart, and electrically coupled to the sensing circuit 86 and for sensing cardiac electrical signals.

[0076] The sensing circuit 86 may include an atrial (A) sensing channel 87 and a ventricular (V) sensing channel 89. The distal shell-based electrode 22 and the proximal shell-based electrode 24 may be coupled to the atrial sensing channel 87 for sensing atrial signals, such as a P wave accompanying atrial myocardial depolarization. In examples including two or more selectable distal shell-based electrodes, the sensing circuit 86 may include a switching circuit system for selectively coupling one or more of the available distal shell-based electrodes to the cardiac event detection circuit system included in the atrial sensing channel 87. The switching circuit system may include a switch array, a switch matrix, a multiplexer, or any other type of switching device suitable for selectively coupling components of the sensing circuit 86 to selected electrodes. The tip electrode 42 and the proximal shell-based electrode 24 may be coupled to the ventricular sensing channel 89 for sensing ventricular signals, such as an R wave accompanying a ventricular myocardial depolarization.

[0077] Each of the atrial sensing channel 87 and the ventricular sensing channel 89 may include cardiac event detection circuitry for detecting P waves and R waves, respectively, from cardiac electrical signals received by the corresponding sensing channel. The cardiac event detection circuitry included in each of the channels 87 and 89 may be configured to amplify, filter, digitize, and rectify cardiac electrical signals received from selected electrodes to improve the signal quality for detecting cardiac electrical events. The cardiac event detection circuitry within each of the channels 87 and 89 may include one or more sense amplifiers, filters, rectifiers, threshold detectors, comparators, analog-to-digital converters (ADCs), timers, or other analog or digital components. The cardiac event sensing thresholds, e.g., P wave sensing thresholds and R wave sensing thresholds, may be automatically adjusted by each corresponding sensing channel 87 and 89 under the control of the control circuit 80, for example, based on a timing period and sensing threshold determined by the control circuit 80, stored in the memory 82, and / or controlled by the hardware, firmware, and / or software of the control circuit 80 and / or the sensing circuit 86.

[0078] Upon detecting a cardiac electrical event based on a sensing threshold crossing, the sensing circuit 86 may generate a sensed event signal that is transmitted to the control circuit 80. For example, the atrial sensing channel 87 may generate a P-wave sensed event signal in response to a P-wave sensing threshold crossing. The ventricular sensing channel 89 may generate an R-wave sensed event signal in response to an R-wave sensing threshold crossing. The sensed event signal may be used by the control circuit 80 to set a pacing escape interval timer that controls a base time interval for scheduling cardiac pacing pulses. The sensed event signal may trigger or inhibit a pacing pulse depending on a specific programmed pacing mode. For example, a P-wave sensed event signal received from the atrial sensing channel 87 may cause the control circuit 80 to inhibit a scheduled atrial pacing pulse and schedule a ventricular pacing pulse at a programmed atrioventricular (AV) pacing interval. If an R-wave is sensed before the expiration of the AV pacing interval, the ventricular pacing pulse may be inhibited. If the AV pacing interval expires before control circuit 80 receives an R-wave sense event signal from ventricular pacing channel 89, control circuit 80 may use therapy delivery circuit 84 to deliver scheduled ventricular pacing pulses synchronized with the sensed P wave.

[0079] In some examples, the device 10 may be configured to deliver various pacing therapies, including bradycardia pacing, cardiac resynchronization therapy, post-shock pacing, and / or tachycardia-related therapies, such as ATP, etc. For example, the device 10 may be configured to detect non-sinus tachycardia and deliver ATP. The control circuit 80 may determine cardiac event time intervals, such as the PP interval between consecutive P wave sense event signals received from the atrial sensing channel 87, the RR interval between consecutive R wave sense event signals received from the ventricular sensing channel 89, and the PR and / or RP intervals received between the P wave sense event signal and the R wave sense event signal. These intervals may be compared to the tachycardia detection interval for detecting non-sinus tachycardia. Tachycardia may be detected in a given heart chamber based on a threshold number of tachycardia detection intervals being detected.

[0080] The therapy delivery circuit 84 may include an atrial pacing circuit 83 and a ventricular pacing circuit 85. Each pacing circuit 83 and 85 may include charging circuitry, one or more charge storage devices (such as one or more low voltage holding capacitors), an output capacitor, and / or switching circuitry that controls when the holding capacitor(s) are charged and when they are discharged across the output capacitor to deliver pacing pulses to a pacing electrode vector coupled to the respective pacing circuit 83 or 85. The tip electrode 42 and the proximal housing-based electrode 24 may be coupled to the ventricular pacing circuit 85 as a bipolar cathode and anode pair for delivering ventricular pacing pulses, e.g., upon expiration of an AV or VV pacing interval set by the control circuit 80, for providing atrial synchronized ventricular pacing as well as a basal lower ventricular pacing rate.

[0081] The atrial pacing circuit 83 can be coupled to the distal shell-based electrode 22 and the proximal shell-based electrode 24 for delivering atrial pacing pulses. The control circuit 80 can set the atrial pacing interval according to a programmed lower pacing frequency, or to a temporary lower frequency set according to the pacing frequency indicated by the frequency response sensor. If the atrial pacing interval expires before a P-wave sense event signal is received from the atrial sensing channel 87, the atrial pacing circuit can be controlled to deliver an atrial pacing pulse. The control circuit 80 starts the AV pacing interval in response to the delivered atrial pacing pulse to provide synchronized multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing).

[0082] Charging of the holding capacitor of the atrial or ventricular pacing circuit 83 or 85 to a programmed pacing voltage amplitude and discharging of the capacitor to a programmed pacing pulse width may be performed by the therapy delivery circuit 84 based on control signals received from the control circuit 80. For example, a pacing timing circuit included in the control circuit 80 may include a programmable digital counter set by a microprocessor of the control circuit 80 for controlling basal pacing time intervals associated with various single-chamber or multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing) modes or anti-tachycardia pacing sequences. The microprocessor of the control circuit 80 may also set the amplitude, pulse width, polarity or other characteristics of the cardiac pacing pulses, which parameters may be based on programmed values ​​stored in the memory 82.

[0083] The device 10 may include other sensors 90 for sensing signals from the patient for use in determining the need for and / or controlling the electrical stimulation therapy delivered by the therapy delivery circuitry 84. In some examples, the sensor indicating the need for increased cardiac output may include a patient activity sensor, such as an accelerometer. An increase in the patient's metabolic demand due to increased activity as indicated by the patient activity sensor may be determined by the control circuitry 80 for use in determining the sensor-indicated pacing rate.

[0084] The control parameters utilized by the control circuit 80 for sensing cardiac events and controlling the delivery of pacing therapy may be programmed into the memory 82 via a telemetry circuit 88, which may also be described as a communication interface. The telemetry circuit 88 includes a transceiver and an antenna for communicating with an external device (such as a programmer or a home monitor) using radio frequency communications or other communication protocols. The control circuit 80 may use the telemetry circuit 88 to receive downlink telemetry from the external device and to send uplink telemetry to the external device. In some cases, the telemetry circuit 88 may be used to transmit communication signals to and receive communication signals from another medical device implanted in the patient.

[0085] Figure 57 is a three-dimensional perspective view of another leadless intracardiac medical device 710 that can be configured for single-chamber or multi-chamber cardiac therapy (e.g., dual-chamber or triple-chamber cardiac therapy) according to another example. The device 710 may include a housing 730 having an outer sidewall 735, shown as a cylindrical outer sidewall, extending from a housing distal end region 732 to a housing proximal end region 734. The housing 730 may enclose an electronic circuit system configured to perform a single-chamber or multi-chamber cardiac therapy including atrial and ventricular cardiac electrical signal sensing and pacing atrial and ventricular chambers. A delivery tool interface member 726 is shown on the housing proximal end region 734.

[0086] The distal fixation and electrode assembly 736 may be coupled to the housing distal end region 732. The distal fixation and electrode assembly 736 may include an electrically insulating distal member 772 coupled to the housing distal end region 732. The tissue piercing electrode 712 and the plurality of non-tissue piercing electrodes 722 extending away from the housing distal end region 732 may be directly coupled to the insulating distal member 772. The tissue piercing electrode 712 extends away from the housing distal end region 732 in a longitudinal direction and may be coaxial with the longitudinal center axis 731 of the housing 730.

[0087] The tissue piercing distal electrode 712 may include an electrically insulating shaft 740 and a tip electrode 742. In some examples, the tissue piercing distal electrode 712 is an active fixation member that includes a helical shaft 740 and a distal cathode tip electrode 742. The helical shaft 740 may extend from a shaft distal end region 743 to a shaft proximal end region 741, which may be directly coupled to an insulating distal member 772. The helical shaft 740 may be coated with an electrically insulating material (e.g., polyparaxylene or other examples listed herein) to avoid sensing or stimulation of cardiac tissue along the length of the shaft. The tip electrode 742 is at the shaft distal end region 743 and may act as a cathode electrode for delivering ventricular pacing pulses and sensing ventricular electrical signals using a proximal housing-based electrode 724 as a return anode when the tip electrode 742 is advanced into the ventricular tissue. The proximal housing-based electrode 724 may be a ring electrode surrounding the housing 730 and may be defined by a non-insulated portion of a longitudinal sidewall 735. Other portions of the housing 730 that do not serve as electrodes may be coated with Figure 2 Electrically insulating materials as described.

[0088] The use of two or more tissue piercing electrodes (e.g., of any type) pierced into the LV myocardium can be used for more localized pacing capture and can mitigate ventricular pacing spikes that affect captured atrial tissue. In some embodiments, the multiple tissue piercing electrodes may include dart-type electrodes (e.g., Figure 1-Figure 212 in the pacing apparatus), two or more of a spiral electrode (e.g., electrode 712). Non-limiting examples of multiple tissue piercing electrodes include two dart electrodes, a spiral electrode with a dart electrode extending therefrom (e.g., through the center), or a double intertwined spiral. Multiple tissue piercing electrodes can also be used for bipolar or multipolar pacing.

[0089] In some embodiments, the one or more tissue piercing electrodes (e.g., any type of tissue piercing electrodes) punctured into the LV myocardium can be multipolar tissue piercing electrodes. The multipolar tissue piercing electrodes can include one or more electrically active or electrically isolated elements that can enable bipolar or multipolar pacing from the one or more tissue piercing electrodes.

[0090] A plurality of non-tissue piercing electrodes 722 may be provided along the periphery of the insulating distal member 772, located around the tissue piercing electrode 712. The insulating distal member 772 may define a distally facing surface 738 of the device 710 and a circumferential surface 739 that surrounds the device 710 and is adjacent to the housing longitudinal sidewall 735. The non-tissue piercing electrodes 722 may be formed of a conductive material such as titanium, platinum, iridium, or alloys thereof. In the illustrated embodiment, six non-tissue piercing electrodes 722 are radially spaced at equal distances along the periphery of the insulating distal member 772, however, two or more non-tissue piercing electrodes 722 may be provided.

[0091] The non-tissue piercing electrodes 722 can be discrete components, each held in a corresponding groove 774 in an insulating member 772, the size and shape of the corresponding groove 774 being designed to be paired with the non-tissue piercing electrodes 722. In other examples, the non-tissue piercing electrodes 722 can each be a non-insulated exposed portion of an integral member mounted in or on an insulating distal member. The middle portion of the integral member that is not used as an electrode can be insulated by the insulating distal member 772, or if exposed to the surrounding environment, can be coated with an electrically insulating coating (e.g., polyparaxylene, polyurethane, silicone, epoxy resin or other insulating coating).

[0092] When tissue piercing electrode 712 is advanced into cardiac tissue, at least one non-tissue piercing electrode 722 may be positioned against the surface of cardiac tissue, positioned in close contact with the surface of cardiac tissue, or positioned operably adjacent to the surface of cardiac tissue for delivering pulses and / or sensing cardiac electrical signals generated by the patient's heart. For example, when tissue piercing electrode 712 is advanced into atrial tissue and passes through the central fiber body until distal tip electrode 742 is positioned in direct contact with ventricular tissue (e.g., ventricular myocardium and / or a portion of the ventricular conduction system), non-tissue piercing electrode 722 may be positioned in contact with right atrial endocardial tissue for pacing and sensing in the atrium.

[0093] The non-tissue piercing electrode 722 may be coupled to a therapy delivery circuit 84 and a sensing circuit 86 enclosed by a housing 730 (see Figure 4 ), to collectively function as cathode electrodes for delivering atrial pacing pulses in combination with a proximal housing-based electrode 724 as a return anode and sensing atrial electrical signals, such as P waves. The switch circuitry included in the sensing circuit 86 may be activated under the control of the control circuit 80 to couple one or more of the non-tissue piercing electrodes to the atrial sensing channel 87. The distal non-tissue piercing electrodes 722 may be electrically isolated from one another so that each individual one of the electrodes 722 may be individually selected by the switch circuitry included in the therapy delivery circuit 84 to function alone or in combination with two or more of the electrodes 722 as an atrial cathode electrode. The switch circuitry included in the therapy delivery circuit 84 may be activated under the control of the control circuit 80 to couple one or more of the non-tissue piercing electrodes 722 to the atrial pacing circuit 83. Two or more of the non-tissue piercing electrodes 722 may be selected at one time to operate as multiple atrial cathode electrodes.

[0094] Certain non-tissue piercing electrodes 722 selected for atrial pacing and / or atrial sensing may be selected based on atrial capture threshold detection, electrode impedance, P-wave signal strength in the cardiac electrical signal, or other factors. For example, a single electrode or any combination of electrodes that provides an optimal combination of low pacing capture threshold amplitude and relatively high electrode impedance among two or more single non-tissue piercing electrodes 722 acting as cathode electrodes may be selected to achieve reliable atrial pacing using minimal current consumption from power supply 98.

[0095] In some instances, when the tissue piercing electrode 712 anchors the housing 730 at the implantation site, the distal-facing surface 738 may uniformly contact the atrial endocardial surface. In this case, all of the electrodes 722 may be selected together to form an atrial cathode. Alternatively, every other electrode in the electrodes 722 may be selected together to form a multi-point atrial cathode having a higher electrical impedance that is still uniformly distributed along the distal-facing surface 738. Alternatively, a subset of one or more electrodes 722 along one side of the insulating distal member 772 may be selected to provide pacing at a desired site, which achieves a minimum pacing capture threshold due to the relative position of the electrodes 722 to the atrial tissue being paced.

[0096] In other examples, depending on the positioning and orientation of the tissue piercing electrode 712 into the heart tissue, the distally facing surface 738 may be oriented at an angle relative to the adjacent endocardial surface. In this case, one or more of the non-tissue piercing electrodes 722 may be positioned to be in closer contact with the adjacent endocardial tissue than other non-tissue piercing electrodes 722, which may be angled with the endocardial surface. By providing multiple non-tissue piercing electrodes along the periphery of the insulating distal member 772, the angles of the tissue piercing electrodes 712 and the housing distal end region 732 relative to the heart surface (e.g., the right atrial endocardial surface) may be required to be substantially parallel. Anatomical differences and positional differences may cause the distally facing surface 738 to be angled or tilted with the endocardial surface, however, multiple non-tissue piercing electrodes 722 distributed along the periphery of the insulating distal member 772 increase the likelihood of good contact between one or more electrodes 722 and adjacent heart tissue to facilitate acceptable pacing thresholds and reliable cardiac event sensing using at least a subset of the multiple electrodes 722. Circumferential contact or fixation along the entire periphery of the insulating distal member 772 may not be required.

[0097] The non-tissue piercing electrodes 722 are shown as each including a first portion 722a extending along the distally facing surface 738 and a second portion 722b extending along the circumferential surface 739. The first portion 722a and the second portion 722b can be continuous exposed surfaces so that the effective electrode surface is wrapped around the peripheral edge 776 of the insulating distal member 772, which is engaged with the distally facing surface 738 and the circumferential surface 739. The non-tissue piercing electrodes 722 may include one or more of the electrodes 772 along the distally facing surface 738, one or more electrodes along the circumferential surface 739, one or more electrodes extending along both the distally facing surface 738 and the circumferential surface 739, or any combination thereof. The exposed surface of each of the non-tissue piercing electrodes 722 may be flush with the corresponding distally facing surface 738 and / or circumferential surface. In other examples, each of the non-tissue piercing electrodes 722 may have an elevated surface protruding from the insulating distal member 772. However, any elevated surface of electrode 722 may define a smooth or rounded non-tissue piercing surface.

[0098] The distal fixation and electrode assembly 736 can seal the distal end region of the housing 730 and can provide a base on which the electrodes 722 are mounted. The electrodes 722 can be referred to as housing-based electrodes. These electrodes 722 can be carried without a shaft or other extension that extends the active electrode portion away from the housing 730, like the distal tip electrode 742 that resides at the distal tip of the helical shaft 740 that extends away from the housing 730. Other examples of non-tissue piercing electrodes coupled to the distal-facing surface and / or circumferential surface of the insulated distal member presented herein include the distal housing-based ring electrode 22 ( Figure 3 ), a distal housing-based annular electrode ( Figure 3 ), button electrodes, other shell-based electrodes, and other circumferential ring electrodes. Any non-tissue piercing electrodes that are directly coupled to the distal insulating member and are located on the periphery of the central tissue piercing electrode may be provided to be used individually, together, or in any combination as cathode electrodes for delivering pacing pulses to adjacent cardiac tissue. When ring electrodes (such as the distal ring electrode 22 and / or circumferential ring electrodes) are provided, multiple portions of the ring electrodes may be electrically insulated by the coating to provide multiple distributed non-tissue piercing electrodes along the distal-facing surface and / or circumferential surface of the insulating distal member.

[0099] The non-tissue piercing electrodes 722 and other examples listed above are expected to provide more reliable and effective atrial pacing and sensing compared to tissue piercing electrodes provided along the distal fixation and electrode assembly 736. The atrial chamber walls are relatively thin compared to the ventricular chamber walls. The tissue piercing atrial cathode electrode may extend too deep into the atrial tissue, resulting in unexpected continuous or intermittent capture of the ventricular tissue. Since the ventricular signal has a greater signal strength than the cardiac electrical signal received via the tissue piercing atrial cathode electrode that is physically closer to the ventricular tissue, the tissue piercing atrial cathode electrode may cause interference with the sensed atrial signal. The tissue piercing electrode 712 can be securely anchored into the ventricular tissue to stabilize the implantation position of the device 710 and provide reasonable assurance that the tip electrode 742 is sensing and pacing in the ventricular tissue while the non-tissue piercing electrode 722 is reliably pacing and sensing in the atrium. When the device 710 is implanted in the target implantation area 4 (e.g., such as Figure 1When the tip electrode 742 is inserted into the ventricular septum (shown in FIG. 1 ), the tip electrode 742 can reach the left ventricular tissue for pacing the left ventricle, while the non-tissue piercing electrode 722 provides pacing and sensing in the right atrium. The length of the tissue piercing electrode 712 from the distal-facing surface 738 can be in the range of about 4 mm to about 8 mm to reach the left ventricular tissue. In some examples, the device 710 can achieve four-chamber pacing by delivering atrial pacing pulses from the atrial pacing circuit 83 in the target implant area 4 via the non-tissue piercing electrode 722 to achieve bi-atrial (right atrium and left atrium) capture, and delivering ventricular pacing pulses from the ventricular pacing circuit 85 via the tip electrode 742 advanced into the ventricular tissue from the target implant area 4 to achieve bi-ventricular (right ventricle and left ventricle) capture.

[0100] Figure 6-Figure 14 The invention relates to a device that can be used to locate the device described herein (e.g., in Figure 1-Figure 5 and Figure 16-18 Specifically, each of these methods can be used when positioning or implanting a tissue puncturing electrode from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart.

[0101] Figure 6 is used with, for example Figure 1 Flow chart of a cardiac treatment method 100 for use with a system 2 of FIG. For example, the method 100 may be used with an intracardiac medical device 10 ( Figure 1-Figure 2 ) or 710( Figure 5 ) Method 100 may be used to describe single-chamber or multi-chamber pacing (e.g., dual-chamber or triple-chamber pacing), atrioventricular synchronous pacing, triggered pacing, cardiac resynchronization pacing, or tachycardia-related therapy.

[0102] Method 100 may include process 102, in which activity of the right atrium is monitored. A medical device may use one or more of a plurality of electrodes to monitor electrical activity of a patient's heart. For example, after being implanted, a right atrium electrode (e.g., Figure 2 The proximal shell-based electrode 24 or the distal shell-based electrode 22 of the medical device can be positioned for sensing electrical activity in the right atrium. In some embodiments, the right atrial electrode can be positioned in the volume of the right atrium, or positioned against the right atrial endocardial surface of the patient's heart. In some embodiments, the right atrial electrode can be used to deliver cardiac therapy to the right atrium of the patient's heart. The right atrial electrode can be coupled to the housing of the medical device without leads. For example, the right atrial electrode can be positioned at the distal end region of the housing, or at a position proximal to the distal end region (e.g., the proximal end region of the housing).

[0103] In addition to or in lieu of using right atrial electrodes, the medical device may use a motion sensor to monitor the mechanical activity of the patient's heart. For example, after being implanted, a right atrial motion detector may be positioned for sensing mechanical activity of the right atrium. In some embodiments, the right atrial motion detector may be positioned within the implantable medical device 10. In some embodiments, the right atrial motion detector may be coupled wirelessly or using leads to the implantable medical device 10. The motion detector may be coupled to the same or different sensing circuit as the electrode.

[0104] Method 100 may further include process 104, in which pacing therapy is delivered to the ventricle. For example, in process 104, pacing therapy may be delivered to the left ventricle, the right ventricle, the ventricular septum (e.g., the higher posterior basal septal region), or other portions of the ventricular myocardium in response to the activity of the right atrium monitored in process 102. The monitored activity may include electrical activity, mechanical activity, or both electrical activity and mechanical activity (e.g., using a right atrial electrode and / or a right atrial motion detector). The medical device may use one or more of the plurality of electrodes to deliver cardiac therapy to the patient's heart. For example, after being implanted, a tissue piercing electrode (e.g., a tip electrode 42) may be positioned in the ventricular septum for delivering cardiac therapy to the left ventricle of the patient's heart. The tissue piercing electrode may be coupled to the housing without leads. In some embodiments, the tissue piercing electrode may be used to sense electrical activity of the left ventricle. The tissue piercing electrode may extend from a distal end region of the housing.

[0105] As mentioned above, method 100 can be used with cardiac resynchronization pacing (e.g., cardiac resynchronization therapy). In some embodiments using cardiac resynchronization pacing, pacing can be delivered to one or both ventricles in response to sensed atrial or ventricular events. Examples of cardiac resynchronization pacing include biventricular pacing and univentricular pacing. Univentricular pacing can include left ventricular pacing, right ventricular pacing, or fusion pacing. Various methods of performing cardiac resynchronization pacing are described in U.S. Patent Application Publication No. 2017 / 0340885 (Sambelashvili), entitled “Systems and methods for leadless cardiac resynchronization therapy,” filed on July 31, 2017, and U.S. Patent No. 9,789,319 (Sambelashvili), entitled “Systems and methods for leadless cardiac resynchronization therapy,” issued on October 17, 2017, each of which is incorporated herein by reference in its entirety.

[0106] One type of cardiac resynchronization pacing is biventricular pacing. Biventricular pacing may include pacing the right ventricle (RV) using an RV electrode and pacing the left ventricle (LV) using an LV electrode (e.g., a tissue puncture electrode), the RV electrode and the LV electrode being typically different electrodes. In one or more embodiments, the implantable medical device may be configured to automatically switch between biventricular pacing and fusion pacing. In general, the primary goal may be to ensure that the ventricles are synchronized with each other. Biventricular pacing may be replaced with univentricular pacing or, in particular, fusion pacing to achieve synchronization. The skilled person understands that the patient's heart may be treated using adaptive CRT, in which biventricular pacing may be delivered during a time period (e.g., 1 hour, 1 day, 1 week, etc.), and at another time, fusion pacing may be delivered to restore synchronization of the ventricles. In general, fusion pacing involves pacing the LV. However, there may be a situation where only the RV is paced.

[0107] One type of adaptive CRT is adaptive LV pacing. Adaptive LV pacing can be described as taking advantage of intrinsic RV conduction by pre-pacing the LV to synchronize with intrinsic RV activation. The timing of LV pacing can be automatically adjusted based on the atrial to intrinsic QRS interval measurement (AV interval). One or more embodiments can set LV pacing to occur at approximately 70% of the intrinsic AV interval, but at least 40 ms before the intrinsic QRS.

[0108] One or more other embodiments may configure LV pacing in response to or based on a moderately prolonged QRS. For example, if the QRS width exceeds 120ms, but does not exceed 160ms, LV pacing with fusion is selected. Otherwise, if the QRS width is greater than 160ms, biventricular (BiV) pacing is selected. Achieving a moderately prolonged QRS threshold may be beneficial for patients with heart failure. The efficacy of LV-only pacing or biventricular pacing may be predicted by a moderately prolonged QRS duration. An illustrative moderately prolonged QRS may correspond to a QRS width in the range of 130ms-150ms.

[0109] Adaptive CRT can use intrinsic AV conduction to determine whether to use biventricular pacing or fusion pacing. In one or more embodiments, intrinsic AV conduction can be automatically evaluated. In one or more embodiments, an IMD (e.g., an ICD), a leadless pacing device (IPD) (e.g., an intracardiac medical device), and / or a subcutaneous implantable device (SD) can automatically evaluate intrinsic ventricular conduction based on the QRS duration from a far-field electromyogram (EGM), or the right ventricular sensing to left ventricular sensing (RVs-LVs) interval from an IMD sensing marker is automatically evaluated by the IMD or SD. For further details, U.S. Patent No. 4,374,382 issued to Markowitz et al. describes an IMD sensing marker, which is included herein by reference in its entirety. Based on these results, fusion pacing (i.e., LV pacing only or RV pacing only) or biventricular pacing can be selected. For example, an RVs-LVs interval of no more than 150ms can correspond to LV pacing only, while an RVs-LVs interval of >150ms can switch the algorithm to biventricular pacing. In one or more other embodiments, an RVs-LVs interval of no more than 80 ms corresponds to fusion pacing, while an RVs-LVs interval greater than 80 ms is switched to biventricular pacing. In general, the RVs-LVs are shorter than the corresponding QRS width. Thus, approximately 40 ms are required to sense the beginning of the QRS in the RV, and also to sense the final portion of the QRS in the LV before the end of the QRS.

[0110] Various devices may be used to perform the functions of adaptive CRT. In one or more other embodiments, the IMD may track a moderately prolonged QRS over time and then rely on the trend data to switch between biventricular pacing and fusion pacing. For example, assume that the moderately prolonged QRS for 6 consecutive weeks is 120ms, 125ms, 130ms, 135ms, 140ms, and 145ms, respectively. The increasing trend may trigger a switch to biventricular pacing before the threshold for switching to biventricular pacing is met.

[0111] In another embodiment, the SD may send a control signal to the LPD for initiating CRT. The LPD may sense a cardiac signal (i.e., a second electrical signal) from the patient's heart. Based on the cardiac signal, the LPD may determine whether to deliver CRT from the LPD to the heart. For example, based on the second electrical signal, the LPD may determine that CRT is not necessary. The LPD may consider whether the sensed data meets a pre-specified threshold. For example, if the QRS width does not exceed 120ms, the LPD may inhibit the delivery of CRT therapy (e.g., the LPD may subsequently send a signal to the SD indicating that CRT should not be delivered based on the cardiac signal). The SD may be configured to perform a more detailed analysis in which at least one or more parameters (such as at least two parameters) are evaluated. The SD may then send another command signal that confirms, overrules, or overrides the LPD.

[0112] In another embodiment, the LPD may sense a cardiac signal indicating that a switch between fusion pacing to biventricular pacing should occur, and the LPD will send a signal to the SD. The SD may be configured to send an override signal to the LPD unless certain conditions are met.

[0113] In yet another embodiment, the LPD may determine that, contrary to SD communication, biventricular pacing may be used instead of fusion pacing. In one embodiment, the LPD will deliver biventricular pacing. In one or more other embodiments, the LPD may determine that, contrary to SD communication, fusion pacing may be used instead of biventricular pacing. In this scenario, the LPD may deliver fusion pacing.

[0114] In another embodiment, the SD transmits a control signal to the LPD for initiating CRT. The LPD senses a cardiac signal (i.e., a second electrical signal) from the patient's heart. Based on the cardiac signal, the LPD can determine whether to deliver CRT, or determine the type of CRT delivered from the LPD to the heart. In one or more embodiments, based on the second electrical signal, the LPD can initially determine that CRT should not be used. The initial determination made by the LPD can use a test, such as a threshold value for one or more parameters. In one or more embodiments, the SD can perform a more detailed analysis of whether CRT should be delivered. Using the sensed data from the LPD and / or the SD, the SD can generate another signal to the LPD that confirms, overrules, or overrides the initial determination of the LPD.

[0115] In another embodiment, the LPD can sense a cardiac signal that indicates that a switch between fusion pacing to biventricular pacing should occur. Whether to switch between fusion pacing and biventricular pacing can be determined based on one or more parameters (e.g., moderately prolonged QRS, etc.). The LPD can be configured to automatically switch between fusion pacing and biventricular pacing, or wait until the SD confirms or denies the switch between CRT pacing modes (i.e., fusion pacing and biventricular pacing). The SD can be configured to send a confirmation signal, or send a signal to deny the LPD to switch pacing modes.

[0116] In yet another embodiment, the LPD may determine that biventricular pacing may be used instead of fusion pacing, contrary to SD communication. In one embodiment, the LPD will deliver biventricular pacing. In one or more other embodiments, the LPD may determine that fusion pacing is more desirable than biventricular pacing, contrary to SD communication. In this scenario, the LPD may deliver fusion pacing.

[0117] In one or more other embodiments, a device having similar SD functionality is implanted in the patient's heart. For example, the SD can be used as a conventional ICD or has the SD functionality described herein. An electrical signal is then sensed from the patient's heart, the electrical signal including moderately extended QRS duration data. Based on the moderately extended QRS duration in the sensed electrical signal, a determination is made as to whether cardiac resynchronization pacing therapy (CRT pacing) is appropriate. CRT pacing pulses are delivered to the heart using electrodes. In one or more embodiments, the SD can switch between fusion pacing and biventricular pacing based on data sensed from the heart (e.g., moderately extended QRS, etc.).

[0118] In addition, there are further embodiments that can be implemented using the methods described herein. One or more LPDs carrying one or more electrodes can be implanted in various chambers of the patient's heart, or otherwise in close proximity to the heart muscle. At these locations, the LPD can sense ECG signals with a high signal-to-noise ratio to detect arrhythmias. In addition, the LPD can provide cardiac pacing at the location of the implanted LPD. In some examples, one or both of the SD and the LPD can share detected signals or physiological information (e.g., RR intervals, electrogram morphology measurements, and / or electrocardiograms or electrograms), thereby enabling a device receiving such information to determine the patient's condition (e.g., determining whether the patient has an arrhythmia or whether there is a lack of synchronization between the ventricles). Communication between an LPD and a subcutaneous ICD (SICD) is described in U.S. patent application serial number 13 / 756,085 filed on January 31, 2013, which is incorporated herein by reference in its entirety.

[0119] In some examples, communication between the SICD and the IPD may be used to initiate treatment and / or confirm that treatment should be delivered. The SICD may also transmit a communication message to the LPD that instructs the LPD to change one or more parameters defining the CRT treatment. In this one-way communication example, the SICD may be configured to transmit communications to the LPD, and the LPD may be configured to receive communications from the SICD. Alternatively, one-way communication may be established, whereby the LPD may be configured to transmit communications (e.g., communications from the LPD) to the SICD. In other examples, two-way communication may allow for confirmation of detected cardiac conditions (e.g., ventricular dyssynchrony, tachyarrhythmia, bradycardia, etc.) before any treatment is delivered. The communication between the SD and the LPD is described in detail in U.S. patent application serial number 13 / 756,085, filed on May 26, 2013, entitled “Systems and methods for leadless pacing and shock therapy” (attorney docket number C0001726.USU1), which is incorporated herein by reference in its entirety.

[0120] One or more of the embodiments described herein may utilize far-field sensing to perform cardiac resynchronization pacing. In some embodiments, one or more of the electrodes of the device may be used for far-field sensing of electrical activity in different chambers. For example, a right atrial electrode or a tissue puncture electrode may be used to monitor far-field electrical activity of the right ventricle. Far-field sensing may be particularly useful in cardiac resynchronization pacing as described above. Clarifying RV timing may be used to customize the timing of LV pacing for an individual patient to allow for fusion pacing (e.g., fusion of RV and LV activation).

[0121] Figure 7 is used with, for example Figure 6 1. A flow chart of a pacing therapy method 110 for use with method 100 of FIG. 10. For example, method 110 may be used in process 104, which delivers pacing therapy to a ventricle. Method 110 may be described as an AV resynchronization therapy method.

[0122] Method 110 may include process 112, in which an atrial event is sensed. For example, the atrial event may be a right atrial event in the monitored activity of the right atrium, for example, as mentioned in process 102. The right atrial electrode may be used to sense the right atrial event within the monitored electrical activity of the right atrium. In addition, or alternatively, a right atrial motion detector may be used to sense the right atrial event within the monitored mechanical activity of the right atrium. The atrial event may be determined by a controller of the medical device using the sensing circuit.

[0123] Method 110 may further include process 114 including waiting for a selected AV time period to elapse in response to detecting an atrial event in process 112. For example, a controller of the medical device may wait for a selected AV time period after detecting an atrial event.

[0124] Method 110 may further include process 116, in which ventricular pacing is delivered in response to an atrial event after the AV time period selected in step 114 has elapsed. In some embodiments, process 116 may be performed without process 114. It is contemplated that ventricular pacing may be delivered in response to an atrial event without using the selected AV time period.

[0125] In some embodiments, the AV time period is configured to synchronize atrial events with ventricular events for atrioventricular synchronization. The AV time period may also be configured or modified for improved cardiac resynchronization. For example, the AV time period may be used to pace one or both ventricles for ventricular synchronization described in more detail below (e.g., using biventricular pacing or univentricular pacing, such as fusion pacing).

[0126] Figure 8 is used with, for example Figure 6 100. For example, method 120 may be used in process 104, which delivers pacing therapy to the ventricles. Method 120 may be described as an AV resynchronization therapy method.

[0127] Method 120 may include process 122 in which the Figure 6 ) of the monitoring activity to sense atrial events. Process 122 can be combined with process 112 ( Figure 7 ) are the same or similar.

[0128] Method 120 may further include process 124, in which the activity of the left ventricle is monitored. One or more tissue piercing electrodes may be used to sense the activity of the left ventricle. If more than one tissue piercing electrode is in contact with the LV myocardium, the tissue piercing electrodes may be used to both sense the LV and pace the LV.

[0129] The method 120 may further include a process 126 that starts an AV time period. The method 120 may further include a process 128 that determines whether a ventricular event is sensed in response to the activity monitored in processes 122 and 124. Specifically, process 128 may determine whether a ventricular event is sensed before the AV time period elapses. A controller of the medical device may be used to make this determination. If a ventricular event is not sensed in process 128, the method 120 may branch to process 130. If a ventricular event is sensed, the method 120 may branch to process 132.

[0130] Method 120 may further include process 130, in which ventricular pacing is delivered after the selected AV time period has elapsed. Process 130 may be combined with process 114 ( Figure 7 ) is the same or similar. A controller of the medical device may initiate or perform ventricular pacing using the therapy delivery circuit.

[0131] Method 120 may further include process 132 of inhibiting delivery of ventricular pacing. Inhibiting delivery of ventricular pacing may be described as inhibiting pacing therapy.

[0132] Fig. 9 is used with, for example Figure 1 Flow chart of a tachycardia-related method 140 for use with the system 2 of FIG. For example, the method 140 may be used with the intracardiac medical device 10 ( Figure 1-Figure 2 ) or 710( Figure 5 ) is used together with the method 140. The method 140 can be described as a tachycardia sensing method.

[0133] The method 140 may include a process 142 in which activity of the right atrium is monitored. When implanted, a controller of the medical device may monitor activity of the right atrium using a sensing circuit and a right atrial electrode or a right atrial motion detector.

[0134] The method 140 may further include a process 144 in which the activity of the left ventricle is monitored. When implanted, the controller of the medical device may use the sensing circuit and tissue piercing electrodes, or the left ventricle motion detector, to monitor the activity of the left ventricle.

[0135] Method 140 may further include process 146 in which tachycardia is determined based on the activity monitored in processes 142 and 144. A controller may be used to make this determination.

[0136] Fig.10 is used with, for example Fig. 9140. For example, method 150 may be used in process 146, which determines tachycardia based on monitored activity. Method 150 may be described as a tachycardia classification method. A ventricular tachycardia event may be determined if the monitored V rate exceeds a certain threshold (e.g., 120 bpm) or additionally or alternatively, if the monitored interval between consecutive V events is less than a certain time interval threshold (e.g., 500 ms).

[0137] Method 150 may include process 152, which determines whether the tachycardia rhythm has a 1:1 AV conduction rhythm or characteristics. As used herein, 1:1 AV conduction or rhythm refers to the regularity of each V event being preceded by an A event in terms of AV intervals. A controller of the medical device may be used to make this determination. If a 1:1 AV conduction rhythm is determined, method 150 may continue to process 154. If process 152 does not determine a 1:1 AV conduction rhythm, method 150 may continue to process 156.

[0138] The method 150 may further include a process 154 in which therapy is withheld. For example, in response to determining that the detected rhythm is untreatable, the controller may be used to withhold tachycardia-related therapy.

[0139] Method 150 may further include process 156 (e.g., in response to not determining a 1:1 AV conduction rhythm in process 152), in which a determination is made as to the type of tachycardia therapy to be delivered. For example, a determination may be made that the V rate is faster than a frequency threshold for ventricular fibrillation (e.g., 200 bpm), in which case the device may initiate shock therapy in process 160. If not, the device may initiate anti-tachycardia pacing therapy in process 158.

[0140] Fig.11 is used with, for example Fig.10 150. For example, method 170 may be used in process 156, which determines the type of tachycardia therapy to be delivered.

[0141] Method 170 may include process 172 that performs VV event interval analysis, which includes determining parameters such as median, range, mode-sum, or other metrics that reflect how fast the tachycardia rhythm is and how regular the intervals between consecutive V events are. Method 170 may further include process 174 that performs electrogram morphology analysis. This may include comparing the overall morphology or overall morphological characteristics of different V events within a tachycardia rhythm and determining a morphological similarity index. Details of determining the morphology and frequency regularity of tachycardia events may be described in U.S. Pat. No. 8,594,775 (Ghosh et al.), which is incorporated herein by reference in its entirety.

[0142] Method 170 may further include process 176 in which the frequency and rhythm regularity of tachycardia events are determined based on a combination of monitoring the intervals between consecutive V events (process 172) and the corresponding electrogram morphology (process 174). In some embodiments, monomorphic VT may be determined based on the regularity of consecutive V events and / or the similarity of electrogram morphology corresponding to V events, while a polymorphic rhythm may be determined if both the frequency regularity and morphology similarity criteria are not met.

[0143] Non-limiting examples of tachycardia therapies that can be delivered include anti-tachycardia pacing and shock therapy (e.g., defibrillation therapy). In some embodiments, if a monomorphic VT is determined, the device can initiate anti-tachycardia pacing (ATP). If a polymorphic rhythm is determined, the device can deliver a shock by signaling an external device to initiate shock therapy.

[0144] Examples of tachycardia treatment determination methods that may be used with the methods of the present disclosure, including interval analysis and electrogram morphology analysis, may be described in U.S. Pat. No. 7,031,711 (Brown et al.), issued on April 18, 2016; U.S. Pat. No. 8,594,775 (Ghosh et al.), issued on November 26, 2013; and U.S. Pat. No. 8,750,994 (Ghosh et al.), issued on June 10, 2014, each of which is incorporated herein by reference in its entirety.

[0145] Fig.12 is used with, for example Figure 1 Flow chart of an anti-tachycardia method 190 for use with the system 2 of FIG. 1. For example, the method 190 may be used with the intracardiac medical device 10 and a separate medical device 50 ( Figure 1 )

[0146] Method 190 may include process 192, which determines that tachycardia is present. For example, a controller of the medical device may determine that tachycardia is present based on monitored activity generated using multiple electrodes and / or one or more motion detectors. Process 192 may be associated with Fig. 9 Process 146 or Fig.11 The process 176 is the same or similar.

[0147] Method 190 may further include process 194 of delivering tachycardia-related therapy using the medical device and / or a separate medical device based on the determination of the presence of tachycardia in process 192. For example, the medical device may provide anti-tachycardia pacing using one or more of the plurality of electrodes.

[0148] In some embodiments, another device may perform process 192 to determine whether tachycardia has been detected, and the medical device may be used to perform process 194 to provide tachycardia-related therapy.

[0149] Fig.13 is used with, for example Fig.12 190. For example, method 200 may be included in process 194 of method 190, which delivers tachycardia-related therapy.

[0150] Method 200 may include process 202, which may be related to Fig.11 176, which determines the type of tachycardia to be delivered. Specifically, process 202 can determine whether both the VV event interval (determined in process 172 of method 170) and the electrogram morphology (determined in process 174 of method 170) are regular. If one or both are irregular, method 200 can continue with process 204. If both are regular, method 200 can continue with process 206.

[0151] Method 200 may further include process 204 to deliver shock therapy. Shock therapy may be initiated using a medical device. For example, the medical device may deliver a signaling pulse (e.g., a unique single, high output pacing pulse to the ventricle) or other trigger. The pacing signal or other trigger may be detected by a separate medical device, which may provide the shock.

[0152] Method 200 may further include process 206 of delivering anti-tachycardia pacing therapy (ATP). ATP may be delivered using multiple electrodes of the medical device. After process 206, method 200 may continue using process 208.

[0153] Method 200 may include process 208 for determining whether the V rhythm exceeds a threshold after ATP delivery has been initiated in process 206. Specifically, the V rhythm threshold may be used in conjunction with process 156 ( Fig.10 ) to distinguish monomorphic VT from other types of tachycardia in the same or similar manner. If the V rhythm exceeds the V rhythm threshold, the method 200 can continue to process 204 as described above. If the V rhythm does not exceed the V rhythm threshold, the method can continue using process 210.

[0154] The method may further include a process 210 to monitor for tachycardia. For example, the process 210 may include performing Fig.11 After process 210, method 200 may return to process 202. When the VV event intervals and electrogram morphology are regular, method 200 may continue to loop, for example, unless shock therapy is delivered in process 204.

[0155] Fig.14 is used with, for example Fig.13 Flowchart of an electric shock therapy method 220 for use with method 200. For example, method 220 may be included in process 204, which delivers electric shock therapy. Figure 1 The separate medical device 50 performs method 220.

[0156] Method 220 may begin with process 222, which determines whether a pacing signal has been detected. Fig.13 As described in process 204 of , the medical device may provide a pacing signal that may be detected by a separate medical device. If no pacing signal is detected, method 220 may continue to process 224. If a pacing signal is detected, method 220 may continue using process 226.

[0157] Method 220 can further include process 224 to inhibit therapy. Specifically, process 224 can inhibit a separate medical device (eg, an extravascular ICD) from delivering shock therapy.

[0158] The method 220 may further include a process 226 for delivering an electric shock to cardiac tissue of the patient's heart. Specifically, a separate medical device may be used to provide the shock because, for example, the medical device may not have sufficient battery capacity, size to deliver an effective cardioversion or defibrillation shock, or the positioning of the medical device may not be sufficient to deliver an effective cardioversion or defibrillation shock.

[0159] Fig.15300 (e.g., a top view) of a patient's heart showing a standard 17-segmented view of a left ventricle 320 and a right ventricle 322. The diagram 300 includes a plurality of regions 326 corresponding to different zones of a human heart. As shown, the regions 326 are labeled with numbers 1-17 (which correspond, for example, to a standard 17-segmented model of a human heart, to the 17 segments of a left ventricle of a human heart, etc.). The regions 326 of the diagram 300 may include a basal anterior region 1, a basal anterior septal region 2, a basal infero-septal region 3, a basal inferolateral region 4, a basal inferolateral region 5, a basal anterolateral region 6, a mid-anterior region 7, a mid-anterior septal region 8, a mid-infero-septal region 9, a mid-inferolateral region 10, a mid-inferolateral region 11, a mid-anterolateral region 12, an apical anterior region 13, an apical septal region 14, an apical inferolateral region 15, an apical lateral region 16, and an apical region 17. Also shown are the subseptal and anterior septal regions of the right ventricle 322, as well as the right bundle branch (RBB) and left bundle branch (LBB).

[0160] In some embodiments, any of the tissue puncture electrodes of the present disclosure may be implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. Specifically, the tissue puncture electrode may be implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body.

[0161] Once implanted, the tissue piercing electrode can be positioned at the target implantation area 4 ( Figure 1 ), such as the basal region and / or septal region of the left ventricular myocardium. Referring to FIG. 300 , the basal region includes one or more of the basal anterior region 1, the basal anterior septal region 2, the basal inferior septal region 3, the basal inferior region 4, the mid-anterior region 7, the mid-anterior septal region 8, the mid-inferior septal region 9, and the mid-inferior region 10. Referring to FIG. 300 , the septal region includes one or more of the basal anterior septal region 2, the basal anterior septal region 3, the mid-anterior septal region 8, the mid-inferior septal region 9, and the apical septal region 14.

[0162] In some embodiments, when implanted, the tissue piercing electrode can be positioned in the basal septal region of the left ventricular myocardium. The basal septal region can include one or more of the basal anterior septal region 2, the basal inferior septal region 3, the mid-anterior septal region 8, and the mid-inferior septal region 9.

[0163] In some embodiments, when implanted, the tissue puncture electrode may be positioned in the high lower / posterior basal septal region of the left ventricular myocardium. The high lower / posterior basal septal region of the left ventricular myocardium may include a portion of at least one of the subbasal septal region 3 and the mid-lower septal region 9. For example, the high lower / posterior basal septal region may include a region 324 generally shown as a dashed line boundary. As shown, the dashed line boundary represents an approximation of the approximate location of the high lower / posterior basal septal region and may take a slightly different shape or size depending on the specific application. Without being bound by any particular theory, stimulation of the high septal ventricular myocardium may result in intraventricular synchronous pacing and / or excitation due to the functional electrical coupling between the subendocardial Purkinje fibers and the ventricular muscle.

[0164] Figure 16-18 is a schematic diagram of an illustrative cardiac therapy system 402, 404, 406 including leaded medical devices 408, 418, 428 having electrodes implanted in a patient's heart 8. Many structures of the cardiac therapy systems 402, 404, 406 can be the same as those in the cardiac therapy system 2. Thus, Figure 16-18 Many of the structures depicted in Figure 1 The same numbering as the structures depicted in Figure 16-18 A description of some of the reference numerals shown in FIG. 5 (e.g., a separate medical device 50) can be found in the above description, especially with respect to FIG. Figure 1 description and is not referenced herein Figure 16-18 Repeat the description.

[0165] refer to Fig.16 , a lead medical device 408 includes one or a single implantable lead 410 having a tissue piercing electrode 12 coupled to a distal end region of the lead and implanted within the patient's heart 8. A housing 420 of the lead medical device 408 may be implanted and positioned outside the patient's heart 8. The lead 410 may include a right atrial electrode, and the device 408 may be operated as a dual-channel supported device. In some embodiments, the lead 410 may not include a right atrial electrode. That is, the lead medical device 408 may be a single-channel device that may be used for asynchronous, triggered, or other single-channel pacing. For example, the tissue piercing electrode 12 is positioned as described above (e.g., relative to the right atrial electrode). Fig.15 Figure 300 and relative to Figure 1 When the device 10) is implanted, the lead 410 can sense activity of the left ventricle (LV) or deliver pacing to the LV.

[0166] refer to Fig.17, leaded medical device 418 is similar to leaded medical device 408, except that device 418 includes two implanted leads 410, 412. Specifically, implanted lead 412 may include an electrode coupled to a distal end region of the lead (e.g., a right atrial electrode) and may be implanted in a different location than lead 410. In some embodiments, lead 412 is implanted in a different region of the right atrium. In some embodiments, each lead 410, 412 may contribute one channel to dual channel device 418. For example, lead 410 may sense activity of the left ventricle (LV) or deliver pacing to the LV, and lead 412 may sense activity of the right atrium (RA) or deliver pacing to the RA.

[0167] refer to Fig.18 , leaded medical device 428 is similar to leaded medical device 418, except that device 428 includes three implanted leads 410, 412, 414. Specifically, implanted lead 414 may include an electrode (e.g., a right ventricular electrode) coupled to a distal end region of the lead and may be implanted in a different location than leads 410, 412. In some embodiments, lead 414 is implanted in a region of the right ventricle. In some embodiments, each lead 410, 412, 414 may contribute one channel to multi-channel device 428. For example, lead 410 may sense activity of the left ventricle (LV) or deliver pacing to the LV, lead 412 may sense activity of the right atrium (RA) or deliver pacing to the RA, and lead 414 may sense activity of the right ventricle (RV) or deliver pacing to the RV.

[0168] Fig.19 5 is a state diagram 500 showing different illustrative therapy modes that the implantable medical devices and systems described herein may initiate or enter during operation. Such implantable medical devices and systems may have a nominal state 502 in which the device is configured to perform at least one or more of atrioventricular synchronous pacing, cardiac resynchronization pacing, and tachycardia-related therapy. The device may initiate or switch to a single chamber pacing mode in state 504 in response to detecting atrial fibrillation. Atrial fibrillation may be detected by the device or a separate device. The device may return to the nominal state 502 from state 504.

[0169] The device may initiate or switch to a triggered pacing mode in state 506, in which the device delivers pacing in response to a trigger (e.g., a pacing signal) from a separate device (e.g., an ICD). In some embodiments, the implantable medical device may include only electrodes (e.g., tissue piercing electrodes) for pacing the LV, which are triggered by a separate, or remote, device (e.g., a subcutaneous device or a leaded device) that determines the timing and sends a command or trigger to the implantable medical device to pace the LV to deliver CRT. The device may return to the nominal state 502 from state 506.

[0170] Further, the device may initiate or switch to an asynchronous pacing mode in state 508 in which the device delivers pacing independent of sensing in other chambers. The device may return to the nominal state 502 from state 508 .

[0171] Now refer to Figure 20-22 , which are diagrams of illustrative systems including electrode arrangements. Fig. 20 An illustrative system 1100 including an electrode device 1110, a display device 1130, and a computing device 1140 is depicted in the drawings. The electrode device 1110 shown includes a plurality of electrodes that are incorporated into, or included in, a belt that is wrapped around the chest or torso of a patient 1120. The electrode device 1110 is operatively coupled to the computing device 1140 (e.g., via one or wired electrical connection, wirelessly, etc.) to provide an electrical signal from each of the electrodes to the computing device 1140 for analysis, evaluation, etc. An illustrative electrode device may be described in U.S. Patent No. 9,320,446, issued on April 26, 2016, entitled “Bioelectric Sensor Device and Methods,” which is incorporated herein by reference in its entirety. Further, the illustrative electrode device 1110 will be referred to herein. Figure 21-22 is described in more detail.

[0172] Although not described herein, the illustrative system 1100 may further include an imaging device. The imaging device may be any type of imaging device configured to image at least a portion of the patient or provide an image of at least a portion of the patient in a non-invasive manner. For example, the imaging device may not use any components or parts that can be positioned within the patient to provide an image of the patient, other than non-invasive tools such as contrast agents. It should be understood that the illustrative systems, methods, and interfaces described herein may further use the imaging device to provide non-invasive assistance to a user (e.g., a physician) in conjunction with an assessment of atrial-to-ventricular pacing therapy to position and place a device for delivering VfA cardiac pacing therapy and / or for positioning or selecting a pacing electrode or pacing vector near the patient's heart for atrial-to-ventricular pacing therapy.

[0173] For example, the illustrative systems, methods, and interfaces can: provide image-guided navigation, which can be used to navigate leads within a patient's body, including leadless devices, electrodes, leadless electrodes, wireless electrodes, catheters, etc.; while also providing non-invasive cardiac therapy evaluation, including determining whether a pacing setting from the atrium to the ventricle is acceptable, or determining whether one or more selected parameters are acceptable, such as selected location information (e.g., location information for an electrode targeting a specific location in the left ventricle). No. 2014 / 0371832, filed on June 12, 2013, entitled “Implantable Electrode Location Selection,” No. 2014 / 0371833, filed on June 12, 2013, entitled “Implantable Electrode Location Selection,” No. 2014 / 0323892, filed on March 27, 2014, entitled “Systems, Methods, and Interfaces for Identifying Effective Electrodes,” and No. 2014 / 0323893, filed on March 27, 2014, entitled “Systems, Methods, and Interfaces for Identifying Optical Electrical Illustrative systems and methods for using imaging devices and / or electrode devices are described in U.S. Patent Publication No. 2014 / 0323882, entitled "Systems, Methods, and Interfaces for Identifying Optical Electric Vectors," each of which is incorporated herein by reference in its entirety.

[0174] The illustrative imaging device can be configured to capture X-ray images and / or any other alternative imaging modality. For example, the imaging device can be configured to capture images or image data using concentric fluoroscopy, biplane fluoroscopy, ultrasound, computed tomography (CT), multi-slice computed tomography (MSCT), magnetic resonance imaging (MRI), high-frequency ultrasound (HIFU), optical coherence tomography (OCT), intravascular ultrasound (IVUS), two-dimensional (2D) ultrasound, three-dimensional (3D) ultrasound, four-dimensional (4D) ultrasound, intraoperative CT, intraoperative MRI, etc. Further, it is to be understood that the imaging device can be configured to (e.g., continuously) capture multiple continuous images to provide video frame data. That is, multiple images taken over time using the imaging device can provide video frames, or dynamic movies, data. Additionally, images can also be obtained and displayed in two dimensions, three dimensions, or four dimensions. In more advanced forms, four-dimensional surface rendering of the heart or other regions of the body may also be achieved by combining cardiac data or other soft tissue data from images or from preoperative image data captured by MRI, CT, or echocardiography modalities. Image data sets from hybrid modalities (such as positron emission tomography (PET) combined with CT, or single photon emission computed tomography (SPECT) combined with CT) may also provide functional image data superimposed on the anatomical data, for example, to be used to navigate a therapeutic device to a target location proximate to the heart or other region of interest (e.g., such as a location within the left ventricle, including a selected location within the high posterior basal septum region of the left ventricular cavity).

[0175] Systems and / or imaging devices that may be used in conjunction with the illustrative systems and methods described herein are described in the following applications: U.S. Patent Application Publication No. 2005 / 0008210, published on January 13, 2005 to Evron et al., U.S. Patent Application Publication No. 2006 / 0074285, published on April 6, 2006 to Zarkh et al., U.S. Patent Application Publication No. 2011 / 0112398, published on May 12, 2011 to Zarkh et al., U.S. Patent Application Publication No. 2013 / 0116739, published on May 9, 2013 to Brada et al., U.S. Patent No. 6,980, issued on December 27, 2005 to Evron et al., 675, U.S. Patent No. 7,286,866 issued October 23, 2007 to Okerlund et al., U.S. Patent No. 7,308,297 issued December 11, 2011 to Reddy et al., U.S. Patent No. 7,308,299 issued December 11, 2011 to Burrell et al., U.S. Patent No. 7,321,677 issued January 22, 2008 to Evron et al., U.S. Patent No. 7,346,381 issued March 18, 2008 to Okerlund et al., U.S. Patent No. 7,454,248 issued November 18, 2008 to Burrell et al., 2009 to Vass et al. No. 7,499,743, issued March 3, 2009; No. 7,565,190, issued July 21, 2009, to Okerlund et al.; No. 7,587,074, issued September 8, 2009, to Zarkh et al.; No. 7,599,730, issued October 6, 2009, to Hunter et al.; No. 7,613,500, issued November 3, 2009, to Vass et al.; No. 7,742,629, issued June 22, 2010, to Zarkh et al.; No. 7,747,047, issued June 29, 2010, to Okerlund et al.; No. 7,778,685 issued on August 17, 2010 to Evron et al., No. 7,778,686 issued on August 17, 2010 to Vass et al., No. 7,813,785 issued on October 12, 2010 to Okerlund et al., No. 7,996,063 issued on August 9, 2011 to Vass et al., No. 8,060,185 issued on November 15, 2011 to Hunter et al., and No. 8,401,616 issued on March 19, 2013 to Verard et al., each of which is incorporated herein by reference in its entirety.

[0176] The display device 1130 and the computing device 1140 may be configured to display and analyze data, such as, for example, electrical signals (e.g., electrocardiogram data), cardiac information representing at least one of mechanical cardiac function and electrical cardiac function, etc. The cardiac information may include, for example, electrical heterogeneity information or electrical asynchrony information generated using electrical signals, alternative electrical activation information or data, etc., which are acquired, monitored or collected using the electrode device 1110. In at least one embodiment, the computing device 1140 may be a server, a personal computer, or a tablet computer. The computing device 1140 may be configured to receive input from the input device 1142 and transmit output to the display device 1130. Further, the computing device 1140 may include a data store that may allow access to a processing program or routine and / or one or more other types of data, for example, to drive a graphical user interface configured to non-invasively assist a user in targeting the placement of a pacing device and / or evaluating pacing therapy at the location (e.g., the location of an implanted electrode for pacing, the location of pacing therapy delivered by a specific pacing vector, etc.).

[0177] The computing device 1140 may be operably coupled to the input device 1142 and the display device 1130, for example, to transmit data to and from each of the input device 1142 and the display device 1130. For example, the computing device 1140 may be electrically coupled to each of the input device 1142 and the display device 1130 using, for example, an analog electrical connection, a digital electrical connection, a wireless connection, a bus-based connection, a network-based connection, an Internet-based connection, etc. As further described herein, a user may provide input to the input device 1142 to manipulate or modify one or more graphical depictions displayed on the display device 1130 and to view and / or select one or more pieces of information related to cardiac therapy.

[0178] Although the input device 1142 is depicted as a keyboard, it should be understood that the input device 1142 may include any device capable of providing input to the computing device 1140 in order to perform the functions, methods, and / or logic described herein. For example, the input device 1142 may include a mouse, a trackball, a touch screen (e.g., a capacitive touch screen, a resistive touch screen, a multi-point touch screen, etc.), etc. Similarly, the display device 1130 may include any device capable of displaying information to a user, such as a graphical user interface 1132, the information including cardiac information, text instructions, graphical depictions of electrical activation information, graphical depictions of the anatomy of a human heart, images or graphical depictions of a patient's heart, graphical depictions of leadless and / or leaded pacing devices positioned or placed for providing VfA pacing therapy, graphical depictions of the location of one or more electrodes, graphical depictions of a human torso, images or graphical depictions of a patient's torso, graphical depictions or actual images of implanted electrodes and / or leads, etc. Further, the display device 1130 may include a liquid crystal display, an organic light emitting diode screen, a touch screen, a cathode ray tube display, etc.

[0179] The processing programs or routines stored and / or executed by the computing device 1140 may include programs or routines for the following: computational mathematics, matrix mathematics, dispersion determination (e.g., standard deviation, variance, range, interquartile range, mean absolute difference, mean absolute deviation, etc.), filtering algorithms, maximum determination, minimum determination, threshold determination, moving window algorithms, decomposition algorithms, compression algorithms (e.g., data compression algorithms), calibration algorithms, image construction algorithms, signal processing algorithms (e.g., various filtering algorithms, Fourier transforms, fast Fourier transforms, etc.), normalization algorithms, comparison algorithms, vector mathematics, or any other processing required to implement one or more of the illustrative methods and / or processes described herein. The data stored and / or used by the computing device 1140 may include, for example, electrical signal / waveform data from the electrode device 1110, scattered signals, windowed scattered signals, portions or parts of various signals, electrical activation times from the electrode device 1110, graphics (e.g., graphical elements, icons, buttons, windows, dialog boxes, drop-down menus, graphic areas, graphic regions, 3D graphics, etc.), graphical user interfaces, results from one or more processing programs or routines adopted in accordance with the disclosure of this document (e.g., electrical signals, cardiac information, etc.), or any other data that may be required to perform one and / or more processes or methods described herein.

[0180] In one or more embodiments, the illustrative systems, methods, and interfaces may be implemented using one or more computer programs executed on a programmable computer, such as a computer including, for example, processing power, data storage (e.g., volatile or non-volatile memory and / or storage elements), input devices, and output devices. The program code and / or logic described herein may be applied to input data in order to perform the functions described herein and generate desired output information. The output information may be applied as input to one or more other devices and / or methods as described herein or as will be applied in a known manner.

[0181] Any programmable language can be used to provide one or more programs for implementing the system, method, and / or interface described herein, such as a high-level procedural programming language and / or an object-oriented programming language suitable for communicating with a computer system. Any such program can be, for example, stored on any suitable device (e.g., storage medium) readable by a general-purpose program or a special-purpose program, which runs on a computer system (e.g., including a processing device) for configuring and operating the computer system when reading suitable equipment to perform the program described herein. That is, at least in one embodiment, an illustrative system, method, and / or interface can be implemented using a computer-readable storage medium configured with a computer program, wherein the storage medium so configured causes the computer to operate in a specific and predefined manner to perform the function described herein. Further, in at least one embodiment, an illustrative system, method, and / or interface can be described as being implemented by logic (e.g., target code) encoded in one or more non-transient media, which include codes for performing and operable to perform operations such as methods, processes, and / or functions described herein when executed by a processor.

[0182] The computing device 1140 can be, for example, any fixed or mobile computer system (e.g., a controller, a microcontroller, a personal computer, a minicomputer, a tablet computer, etc.) and can be generally described as including a processing circuit system. The exact configuration of the computing device 1140 is not limiting, and substantially any device that can provide appropriate computing power and control capabilities (e.g., graphics processing, etc.) can be used. As described herein, a digital file can be any medium (e.g., volatile or non-volatile memory, CD-ROM, punch cards, magnetically readable media such as disks or tapes, etc.) containing digital bits (e.g., encoded in binary, ternary, etc.) that can be read and / or written by the computing device 1140 described herein. Similarly, as described herein, a file in a user-readable format can be any data representation (e.g., ASCII text, binary numbers, hexadecimal numbers, decimal numbers, diagrams, etc.) that can be presented on any medium (e.g., paper, display, etc.) that is readable and / or understandable by a user.

[0183] In view of the foregoing, it will be apparent that the functionality as described in one or more embodiments according to the present disclosure may be implemented in any manner as will be known to those skilled in the art. Thus, the computer language, computer system, or any other software / hardware used to implement the processes described herein should not be limited to the scope of the systems, processes, or programs described herein (e.g., the functionality provided by such systems, processes, or programs).

[0184] The electrical activation time of a patient's heart may be useful for assessing the patient's cardiac condition and / or delivering atrium-to-ventricle (VfA) cardiac therapy to the patient. Fig. 20 as well as Figure 21-22 The electrode device 1110 shown in FIG. monitors or determines surrogate electrical activation information or data of one or more regions of the patient's heart. The illustrative electrode device 1110 may be configured to measure the body surface potential of the patient 1120, and more specifically, the torso surface potential of the patient 1120. Fig.21 As shown, the illustrative electrode device 1110 can include a set of electrodes 1112 or an array of electrodes 1112, a strap 113, and an interface / amplifier circuit system 1116. In at least one embodiment, a portion of the electrode set can be used, wherein the portion corresponds to a specific location on the patient's heart. The electrodes 1112 can be attached or coupled to the strap 1113 and the strap 1113 can be configured to wrap around the torso of the patient 1120 so that the electrodes 1112 surround the patient's heart. As further shown, the electrodes 1112 can be positioned around the periphery of the patient 1120, including a posterior position, a lateral position, a posterior lateral position, an anterior lateral position, and an anterior position of the torso of the patient 1120.

[0185] Further, the electrodes 1112 may be electrically connected to an interface / amplifier circuitry 1116 via a wired connection 1118. The interface / amplifier circuitry 1116 may be configured to amplify signals from the electrodes 1112 and provide these signals to a computing device 1140. Other illustrative systems may use a wireless connection to transmit signals sensed by the electrodes 1112 to the interface / amplifier circuitry 1116, and in turn to the computing device 1140, e.g., as multi-channel data. For example, the interface / amplifier circuitry 1116 may be electrically coupled to each of the computing device 1140 and the display device 1130 using, for example, an analog electrical connection, a digital electrical connection, a wireless connection, a bus-based connection, a network-based connection, an Internet-based connection, etc.

[0186] Despite Fig.21 In the example of the electrode device 1110 includes a strap 1113, but in other examples, any of a variety of mechanisms (e.g., tape or adhesive) can be used to help space and place the electrodes 1112. In some examples, the strap 1113 can include an elastic band, a tape strip, or a cloth. In other examples, the electrodes 1112 can be placed individually on the torso of the patient 1120. Further, in other examples, the electrodes 1112 (e.g., arranged in an array) can be part of a patch, a vest or positioned within a patch, a vest, and / or other means of fastening the electrodes 1112 to the torso of the patient 1120.

[0187] The electrodes 1112 can be configured to surround the heart of the patient 1120 and record or monitor electrical signals associated with the depolarization and repolarization of the heart after they have propagated through the torso of the patient 1120. Each of the electrodes 1112 can be used in a unipolar configuration to sense the surface potential of the torso that reflects the cardiac signals. The interface / amplifier circuit system 1116 can also be coupled to a return electrode or neutral electrode (not shown) that can be used in combination with each electrode 1112 for unipolar sensing. In some examples, there may be about 12 to about 50 electrodes 1112 distributed spatially around the patient's torso. Other configurations may have more or fewer electrodes 1112.

[0188] The computing device 1140 can record and analyze electrical activity (e.g., torso surface potential signals) sensed by the electrodes 1112 and amplified / conditioned by the interface / amplifier circuit system 1116. The computing device 1140 can be configured to analyze the signals from the electrodes 1112 to provide them as anterior electrode signals and posterior electrode signals and surrogate cardiac electrical activation times, which are, for example, representative of actual or local electrical activation times of one or more regions of the patient's heart, as will be further described below. The computing device 1140 can be configured to analyze the signals from the electrodes 1112 to provide them as anterior septal electrode signals and surrogate cardiac electrical activation times, which are, for example, representative of actual or local electrical activation times of one or more regions of the patient's heart, as will be further described below, for example, for evaluating VfA pacing therapy. Further, the electrical signal measured at the left anterior surface location of the patient's torso may represent the electrical signal of the left anterior left ventricular region of the patient's heart, or may be a substitute for the electrical signal of the left anterior left ventricular region of the patient's heart; the electrical signal measured at the left lateral surface location of the patient's torso may represent the electrical signal of the left lateral left ventricular region of the patient's heart, or may be a substitute for the electrical signal of the left lateral left ventricular region of the patient's heart; the electrical signal measured at the left posterior lateral surface location of the patient's torso may represent the electrical signal of the posterior lateral left ventricular region of the patient's heart, or may be a substitute for the electrical signal of the posterior lateral left ventricular region of the patient's heart; and the electrical signal measured at the posterior surface location of the patient's torso may represent the electrical signal of the posterior left ventricular region of the patient's heart, or may be a substitute for the electrical signal of the posterior left ventricular region of the patient's heart. In one or more embodiments, the measurement of the excitation time can be performed by measuring the time period between the start of cardiac depolarization (e.g., the start of the QRS complex) and an appropriate reference point, such as, for example, a peak value, a minimum value, a minimum slope, a maximum slope, a zero crossing, a threshold crossing, etc.

[0189] Additionally, computing device 1140 may be configured to provide a graphical user interface that depicts alternative electrical activation times obtained using electrode device 1110. Illustrative systems, methods, and / or interfaces may non-invasively use electrical information collected using electrode device 1110 to assess a patient's cardiac condition and / or deliver atrial-to-ventricular pacing therapy to the patient.

[0190] Fig. 22Another illustrative electrode arrangement 1110 is shown that includes a plurality of electrodes 1112 configured to surround the heart of a patient 1120 and record or monitor electrical signals associated with depolarization and repolarization of the heart after they have propagated through the torso of the patient 1120. The electrode arrangement 1110 may include a vest 1114 to which the plurality of electrodes 1112 may be attached or to which the electrodes 1112 may be coupled. In at least one embodiment, the plurality of electrodes 1112 or an array of electrodes 112 may be used to collect electrical information, such as, for example, surrogate electrical activation times. Fig.21 Similar to the electrode device 1110, Fig. 22 The electrode device 1110 may include an interface / amplifier circuit system 1116 that is electrically coupled to each of the electrodes 1112 via a wired connection 1118 and is configured to transmit signals from the electrodes 1112 to a computing device 1140. As shown, the electrodes 1112 may be distributed on the torso of the patient 1120, including, for example, the anterior surface, the lateral surface, the posterolateral surface, the anterior lateral surface, and the posterior surface of the torso of the patient 1120.

[0191] The vest 1114 may be formed of a braid, wherein the electrodes 1112 are attached to the braid. The vest 1114 may be configured to maintain the position and spacing of the electrodes 1112 on the torso of the patient 1120. Further, the vest 1114 may be marked to assist in determining the position of the electrodes 1112 on the torso surface of the patient 1120. In one or more embodiments, the vest 1114 may include 17 or more front electrodes that may be positioned proximate to the patient's anterior torso, and may include 39 or more rear electrodes that may be positioned proximate to the patient's anterior torso. In some examples, there may be about 25 electrodes 1112 to about 256 electrodes 1112 distributed around the torso of the patient 1120, but other configurations may have more or fewer electrodes 1112.

[0192] As described herein, the electrode device 1110 can be configured to measure electrical information (e.g., electrical signals) representing different regions of the patient's heart. For example, the excitation times of different regions of the patient's heart can be roughly estimated based on surface electrocardiogram (ECG) excitation times measured using surface electrodes near surface areas corresponding to different regions of the patient's heart. In at least one example, the excitation times of the anterior septal region of the patient's heart can be roughly estimated based on surface ECG excitation times measured using surface electrodes near surface areas corresponding to the anterior septal region of the patient's heart. That is, a portion of the electrode group 1112 rather than the entire electrode group can be used to generate an excitation time corresponding to a specific location of the patient's heart corresponding to that portion of the electrode group.

[0193] The illustrative systems, methods, and interfaces may be used to provide non-invasive assistance to a user in assessing a patient's cardiac health or status, and / or in assessing cardiac therapies, such as atrium-to-ventricle (VfA) pacing therapy (e.g., a cardiac therapy currently delivered to a patient during or after implantation) using the electrode device 1110. Further, the illustrative systems, methods, and interfaces may be used to assist a user in configuring a cardiac therapy delivered to a patient, such as VfA pacing therapy.

[0194] VfA pacing can be described as providing synchronized homogeneous excitation of the ventricles of the heart. As an example, a patient with atrioventricular (AV) block or prolonged AV timing that can lead to heart failure (who would have a complete (e.g., normal) QRS if they did not have AV block or prolonged AV timing) can benefit from VfA pacing therapy. Also, as an example, VfA pacing can provide beneficial excitation to heart failure patients with intrinsic ventricular conduction disease. Further, properly placed VfA pacing can provide optimal ventricular excitation for such patients. Further, left ventricular (LV) resynchronization in heart failure patients with left bundle branch block (LBBB) can be found to provide easier access to the left ventricular endocardium without the need to expose a leadless device or leads to the endocardial blood pool. At the same time, in this example, this can help engage a portion of the conduction system to potentially correct the LBBB and effectively resynchronize the patient.

[0195] Fig.23 shows an example using Figure 2 An illustrative method 600 for detecting atrial activity using a motion detector 11 of an IMD. Specifically, method 600 may include detecting atrial contraction based on an analysis of a motion signal (e.g., provided by motion detector 11) that may be performed by an IMD implanted in the patient's heart. In some embodiments, the motion signal may be provided by an IMD implanted in a ventricle (such as the right ventricle) of the patient's heart. Method 600 may include starting an atrial contraction detection delay period (630) when a ventricular activation event is identified. Method 600 may include starting an atrial contraction detection window (632) when the atrial contraction delay period expires. Method 600 may include analyzing the motion signal within the atrial contraction detection window.

[0196] Method 600 may include filtering the motion signal within the atrial contraction detection window, rectifying the filtered signal, and generating a derivative signal of the filtered and rectified motion signal within the atrial contraction detection window (634). Method 600 may include determining whether the amplitude of the derivative signal within the atrial contraction detection window exceeds a threshold (636). In response to determining that the amplitude of the derivative signal within the atrial contraction detection window exceeds the threshold (i.e., the "yes" branch of 636), method 600 may continue to detect atrial contraction (638). Otherwise (i.e., the "no" branch of 636), method 600 may return to filtering, rectifying, and generating the derivative signal (634). Various techniques using a motion detector that provides a motion signal may be described in U.S. Patent No. 9,399,140 (Cho et al.), entitled “Atrial contraction detection by aventricular leadless pacing device for atrio-synchronous ventricular pacing,” issued on July 26, 2016, which is incorporated herein by reference in its entirety.

[0197] Illustrative Embodiments

[0198] However, the present disclosure is not limited thereto, and an understanding of various aspects of the disclosure of the present application may be obtained through a discussion of some illustrative embodiments provided below.

[0199] Various illustrative embodiments relate to atrioventricular synchronous pacing.

[0200] In illustrative embodiment 1, an implantable medical device includes a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle and sensing at least one of the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode positionable within the right atrium for delivering cardiac therapy and sensing at least one of the electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the electrical activity of the right atrium using the right atrial electrode; and deliver atrioventricular synchronous pacing based on the monitored electrical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0201] In illustrative embodiment 2, a method includes: monitoring the activity of the right atrium of a patient's heart using a right atrial electrode or a right atrial motion detector; and delivering atrioventricular synchronous pacing based on the monitored right atrial activity using at least a tissue puncture electrode implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body, including pacing one or both ventricles using the at least one tissue puncture electrode.

[0202] In illustrative embodiment 3, the device or method of any preceding illustrative embodiment is included, wherein delivering atrioventricular synchronous pacing includes pacing the right atrium using a right atrial electrode.

[0203] In illustrative embodiment 4, an apparatus or method of any of the foregoing illustrative embodiments is included, wherein atrioventricular synchronous pacing is delivered based on the monitored electrical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles, including: sensing atrial events within the monitored electrical activity of the right atrium; and delivering pacing to one or both ventricles in response to the sensed atrial events.

[0204] In illustrative embodiment 5, the apparatus or method of illustrative embodiment 4 is included, wherein delivering pacing to one or both ventricles in response to a sensed atrial event includes delivering pacing to one or both ventricles after a selected AV time period has elapsed from the sensed atrial event.

[0205] In illustrative embodiment 6, the device or method of any of the foregoing illustrative embodiments is included, wherein the controller is further configured to perform, or the method further includes: monitoring electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart using a tissue puncture electrode implanted in the basal region and / or septal region of the left ventricular myocardium from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body; sensing ventricular events within the electrical activity monitored using the tissue puncture electrode; and inhibiting delivery of pacing to one or both ventricles in response to sensing ventricular events within the electrical activity monitored using the tissue puncture electrode.

[0206] In illustrative embodiment 7, the apparatus or method of any of the preceding illustrative embodiments is included, wherein the controller is further configured for, or the method further includes: detecting atrial fibrillation and initiating a single chamber pacing mode.

[0207] In illustrative embodiment 8, the device or method of any of the preceding illustrative embodiments is included, wherein the controller is further configured for, or the method further includes: receiving a trigger from a separate medical device in the triggered pacing mode.

[0208] In illustrative embodiment 8, the apparatus or method of any preceding illustrative embodiment is included, wherein the controller is further configured for, or the method further includes: delivering pacing in an asynchronous pacing mode.

[0209] In illustrative embodiment 9, the device of any of the preceding illustrative embodiments is included, further comprising a housing extending from a proximal end region to a distal end region. The right atrial electrode is leadlessly coupled to the housing, and the tissue piercing electrode is leadlessly coupled to the distal end region of the housing. The therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing.

[0210] In illustrative embodiment 10, the device of illustrative embodiment 9 is included, further comprising a fixation member extending from the housing. The fixation member is configured to penetrate into the myocardium. The fixation member extends from a distal end region of the housing toward a distal tip of the tissue piercing electrode.

[0211] In illustrative embodiment 11, the device of any of the preceding illustrative embodiments is included, further comprising a housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises a lead coupled to the housing and extending from the housing to a distal end region. The tissue puncture electrode and the right atrial electrode are coupled to the distal end region of the lead.

[0212] In illustrative embodiment 12, the device of any of the preceding illustrative embodiments is included, further comprising a housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises a first lead coupled to the housing and extending from the housing to a first distal end region, and a second lead coupled to the housing and extending from the housing to a second distal end region. The tissue puncture electrode is coupled to the first distal end region of the first lead. The right atrium electrode is coupled to the second distal end region of the second lead.

[0213] In illustrative embodiment 13, the device of any of the preceding illustrative embodiments is included, further comprising a housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises: a first lead coupled to the housing and extending from the housing to a first distal end region, a second lead coupled to the housing and extending from the housing to a second distal end region, and a third lead coupled to the housing and extending from the housing to a third distal end region. The plurality of electrodes further comprises a right ventricular electrode coupled to a third distal end region of the third lead and used to deliver cardiac therapy to the right ventricle of the patient's heart or to sense electrical activity of the right ventricle of the patient's heart. The tissue puncture electrode is coupled to the first distal end region of the first lead. The right atrium electrode is coupled to the second distal end region of the second lead.

[0214] In illustrative embodiment 14, an implantable medical device includes a housing extending from a proximal end region to a distal end region. The device also includes a plurality of electrodes. The plurality of electrodes include a tissue puncture electrode that is leadlessly coupled to the distal end region of the housing and is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode that is leadlessly coupled to the housing and positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit within the housing that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit within the housing that is operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart. The implantable medical device further includes a controller including a processing circuit system in the housing operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the electrical activity of the right atrium using the right atrial electrode; and deliver atrioventricular synchronous pacing based on the monitored electrical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0215] In illustrative embodiment 15, an implantable medical device includes a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle and sensing at least one of the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The tissue piercing electrode also includes a right atrial motion detector that can be positioned within the right atrium for sensing the mechanical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the mechanical activity of the right atrium using a right atrial motion detector; and deliver atrioventricular synchronous pacing based on the monitored mechanical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0216] Various illustrative embodiments relate to cardiac resynchronization pacing.

[0217] In illustrative embodiment 16, an implantable medical device includes a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle or sensing at least one of the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing at least one of the electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to monitor the electrical activity of the right atrium using a right atrial electrode and monitor the electrical activity of the left ventricle using a tissue piercing electrode implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body. The controller is also configured to deliver cardiac resynchronization pacing based on the monitored electrical activity using at least a tissue piercing electrode implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart through the right atrial endocardium and the central fibrous body to pace one or both ventricles.

[0218] In illustrative embodiment 17, a method includes at least one of: monitoring electrical activity of the right atrium of a patient's heart using a right atrial electrode; and monitoring electrical activity of the left ventricle using a tissue piercing electrode implanted in a basal region and / or septal region of the left ventricular myocardium of the patient's heart from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body. The method also includes: delivering cardiac resynchronization pacing based on the monitored electrical activity, including pacing one or both ventricles, using at least a tissue piercing electrode implanted in a basal region and / or septal region of the left ventricular myocardium of the patient's heart from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body.

[0219] In illustrative embodiment 18, the apparatus or method of any of the preceding illustrative embodiments is included, wherein the controller is further configured for, or the method further includes: monitoring far-field electrical activity of the right ventricle using the right atrial electrode.

[0220] In illustrative embodiment 19, an apparatus or method of any one of illustrative embodiments 16-18 is included, wherein cardiac resynchronization pacing is delivered based on monitored electrical activity using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles, including: sensing atrial events within the monitored electrical activity of the right atrium; and delivering pacing to one or both ventricles in response to the sensed atrial events to provide cardiac resynchronization.

[0221] In illustrative embodiment 20, an apparatus or method of any one of illustrative embodiments 16-19 is included, wherein delivering cardiac resynchronization pacing based on monitored electrical activity using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles includes: sensing ventricular events within the electrical activity monitored using the tissue puncture electrode; and delivering pacing to one or both ventricles in response to the sensed ventricular events to provide cardiac resynchronization.

[0222] In illustrative embodiment 21, the apparatus or method of illustrative embodiment 20 is included, wherein delivering pacing to one or both ventricles in response to a sensed ventricular event includes delivering pacing to one or both ventricles after a selected time period has elapsed from the sensed ventricular event.

[0223] In illustrative embodiment 22, the apparatus or method of any of illustrative embodiments 16-21 is included, wherein the controller is further configured for, or the method further includes: detecting atrial fibrillation and initiating a single chamber pacing mode.

[0224] In illustrative embodiment 23, the device or method of any of illustrative embodiments 16-22 is included, wherein the controller is further configured for, or the method further includes: receiving a trigger from a separate medical device in the triggered pacing mode.

[0225] In illustrative embodiment 24, the apparatus or method of any of illustrative embodiments 16-23 is included, wherein the controller is further configured for, or the method further includes: delivering pacing in an asynchronous pacing mode.

[0226] In illustrative embodiment 25, the device of any one of illustrative embodiments 16-24 is included, further comprising a housing extending from a proximal end region to a distal end region. The right atrial electrode is leadlessly coupled to the housing, and the tissue puncture electrode is leadlessly coupled to the distal end region of the housing. The therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing.

[0227] In illustrative embodiment 26, the device of illustrative embodiment 25 is included, further comprising a fixation member extending from the housing. The fixation member is configured to penetrate into the myocardium. The fixation member extends from a distal end region of the housing toward a distal tip of the tissue piercing electrode.

[0228] In illustrative embodiment 27, the device of any of illustrative embodiments 16-26 is included, further comprising a housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises a lead coupled to the housing and extending from the housing to the distal end region. The tissue puncture electrode and the right atrial electrode are coupled to the distal end region of the lead.

[0229] In illustrative embodiment 28, the device of any of illustrative embodiments 16-27 is included, further comprising a housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises: a first lead coupled to the housing and extending from the housing to a first distal end region, and a second lead coupled to the housing and extending from the housing to a second distal end region. The tissue puncture electrode is coupled to the first distal end region of the first lead. The right atrium electrode is coupled to the second distal end region of the second lead.

[0230] In illustrative embodiment 29, the device of any of illustrative embodiments 16-28 is included, further comprising a housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises: a first lead coupled to the housing and extending from the housing to a first distal end region, a second lead coupled to the housing and extending from the housing to a second distal end region, and a third lead coupled to the housing and extending from the housing to a third distal end region. The plurality of electrodes further comprises a right ventricular electrode coupled to a third distal end region of the third lead and used to deliver cardiac therapy to the right ventricle of the patient's heart or to sense electrical activity of the right ventricle of the patient's heart. The tissue puncture electrode is coupled to the first distal end region of the first lead. The right atrium electrode is coupled to the second distal end region of the second lead.

[0231] In illustrative embodiment 30, an implantable medical device includes a housing extending from a proximal end region to a distal end region. The implantable medical device also includes a plurality of electrodes. The plurality of electrodes include a tissue puncture electrode that is leadlessly coupled to the distal end region of the housing and is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode that is leadlessly coupled to the housing and positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit within the housing that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; a sensing circuit within the housing that is operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart. The implantable medical device further includes a controller, which includes a processing circuit system operably coupled to the treatment delivery circuit and the sensing circuit within the housing. The controller is configured for at least one of the following: monitoring the electrical activity of the right atrium using the right atrial electrode; and, monitoring the electrical activity of the left ventricle using a tissue puncture electrode that passes from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body and in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The controller is further configured to deliver cardiac resynchronization pacing based on the monitored electrical activity using at least a tissue puncture electrode that passes from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body and is implanted in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0232] In illustrative embodiment 31, an implantable medical device includes a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle and sensing at least one of the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial motion detector that can be positioned within the right atrium for sensing the mechanical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing the electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the mechanical activity of the right atrium using a right atrial motion detector; and deliver cardiac resynchronization pacing based on the monitored mechanical activity of the right atrium using at least a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

[0233] Various illustrative embodiments relate to tachycardia treatment.

[0234] In illustrative embodiment 32, an implantable medical device includes a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode that is positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the electrical activity of the right atrium using a right atrial electrode; monitor the electrical activity of the left ventricle using a tissue-piercing electrode, which is implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to sense the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium; and deliver tachycardia therapy based on the monitored electrical activity of the right atrium and left ventricle.

[0235] In illustrative embodiment 33, a method includes: monitoring the electrical activity of the right atrium of a patient's heart using a right atrial electrode; monitoring the electrical activity of the left ventricle of the patient's heart using a tissue-piercing electrode, the tissue-piercing electrode being implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body into the basal region and / or septal region of the left ventricular myocardium of the patient's heart to sense the electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium; and delivering tachycardia therapy based on the monitored electrical activity of the right atrium and left ventricle.

[0236] In illustrative embodiment 34, the device or method of any of illustrative embodiments 32-33 is included, wherein the controller is configured to perform, or the method further includes: delivering tachycardia therapy based on monitored electrical activity of the right atrium and left ventricle includes at least one of the following: delivering anti-tachycardia pacing therapy using multiple electrodes, and delivering electric shock therapy using a separate medical device.

[0237] In illustrative embodiment 35, the apparatus or method of any of illustrative embodiments 32-34 is included, wherein the controller is further configured to perform, or the method further includes: in response to determining that the heart rhythm of the patient's heart has 1:1 atrioventricular conduction, inhibiting tachycardia therapy.

[0238] In illustrative embodiment 36, the device of any one of illustrative embodiments 32-35 is included, further including a shell extending from a proximal end region to a distal end region, wherein a right atrial electrode is leadlessly coupled to the shell and a tissue puncture electrode is leadlessly coupled to the distal end region of the shell, wherein a therapy delivery circuit, a sensing circuit, and a controller are enclosed within the shell.

[0239] In illustrative embodiment 37, the device of illustrative embodiment 36 is included, further comprising a fixation member extending from the housing. The fixation member is configured to penetrate into the myocardium. The fixation member extends from a distal end region of the housing toward a distal tip of the tissue piercing electrode.

[0240] In illustrative embodiment 38, the device of any one of illustrative embodiments 32-37 is included, further comprising a housing, wherein the treatment delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises a lead coupled to the housing and extending from the housing to the distal end region. The tissue puncture electrode and the right atrial electrode are coupled to the distal end region of the lead.

[0241] In illustrative embodiment 39, the device of any of illustrative embodiments 32-38 is included, further comprising a housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises: a first lead coupled to the housing and extending from the housing to a first distal end region, and a second lead coupled to the housing and extending from the housing to a second distal end region. The tissue puncture electrode is coupled to the first distal end region of the first lead. The right atrium electrode is coupled to the second distal end region of the second lead.

[0242] In illustrative embodiment 40, the device of any of illustrative embodiments 32-39 is included, further comprising a housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing. The device further comprises: a first lead coupled to the housing and extending from the housing to a first distal end region, a second lead coupled to the housing and extending from the housing to a second distal end region, and a third lead coupled to the housing and extending from the housing to a third distal end region. The plurality of electrodes further comprises a right ventricular electrode coupled to a third distal end region of the third lead and used to deliver cardiac therapy to the right ventricle of the patient's heart or to sense electrical activity of the right ventricle of the patient's heart. The tissue puncture electrode is coupled to the first distal end region of the first lead. The right atrium electrode is coupled to the second distal end region of the second lead.

[0243] In illustrative embodiment 41, an implantable medical device includes a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode that is positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured to: monitor the electrical activity of the right atrium using a right atrial electrode; monitor the electrical activity of the left ventricle using a tissue puncture electrode, which is implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body in the basal area and / or septal area of ​​the left ventricular myocardium of the patient's heart to sense the electrical activity of the left ventricle; and determine tachycardia of the patient's heart based on the monitored electrical activities of the right atrium and left ventricle.

[0244] In illustrative embodiment 42, a method includes: monitoring the electrical activity of the right atrium of a patient's heart using a right ventricular electrode; monitoring the electrical activity of the left ventricle of the patient's heart using a tissue-piercing electrode, the tissue-piercing electrode being implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body and in the basal region and / or septal region of the left ventricular myocardium of the patient's heart to sense the electrical activity of the left ventricle; and determining tachycardia of the patient's heart based on the monitored electrical activity of the right atrium and left ventricle.

[0245] In illustrative embodiment 43, the apparatus or method of any of illustrative embodiments 41-42 is included, wherein the controller is further configured to perform, or the method further includes: determining whether the heart rhythm of the patient's heart has 1:1 atrioventricular conduction.

[0246] In illustrative embodiment 44, the device or method of illustrative embodiment 43 is included, wherein the controller is further configured to perform, or the method further includes: determining appropriate tachycardia treatment in response to the heart rhythm not having 1:1 atrioventricular conduction based on the monitored electrical activity of the right atrium and left ventricle.

[0247] In illustrative embodiment 45, the apparatus or method of any of illustrative embodiments 41-44 is included, wherein determining tachycardia of the patient's heart based on monitored electrical activity of the right atrium and left ventricle includes: determining that the atrial rhythm is regular, and determining that the ventricular rhythm exceeds a selected ventricular rhythm threshold.

[0248] In illustrative embodiment 46, the apparatus or method of any of illustrative embodiments 41-45 is included, wherein the controller is further configured for, or the method further includes: delivering tachycardia therapy in response to determining tachycardia of the patient's heart.

[0249] In illustrative embodiment 47, the apparatus or method of illustrative embodiment 46 is included, wherein the controller is further configured to perform, or the method further includes: delivering anti-tachycardia pacing therapy in response to regular VV event intervals and regular electrogram morphology.

[0250] In illustrative embodiment 48, the device or method of any of illustrative embodiments 46-47 is included, wherein the controller is further configured to perform, or the method further includes: delivering electric shock therapy using a separate medical device in response to at least one of irregular VV event intervals and irregular electrogram morphology.

[0251] In illustrative embodiment 49, an implantable medical device includes a plurality of electrodes. The plurality of electrodes include a tissue piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart. The plurality of electrodes also include a right atrial electrode that is positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart. The implantable medical device also includes: a therapy delivery circuit that is operably coupled to the plurality of electrodes for delivering cardiac therapy to the patient's heart; and a sensing circuit that is operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart. The implantable medical device further includes a controller that includes a processing circuit system that is operably coupled to the therapy delivery circuit and the sensing circuit. The controller is configured for at least one of: delivering anti-tachycardia pacing therapy using the plurality of electrodes, and delivering electrical shock therapy using a separate medical device.

[0252] In illustrative embodiment 50, a method includes delivering at least one of anti-tachycardia pacing therapy and delivering electrical shock therapy using a separate medical device using at least a tissue-piercing electrode that is implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body to deliver cardiac therapy to the left ventricle or sense electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart.

[0253] In illustrative embodiment 51, the device or method of any of illustrative embodiments 49-59 is included, wherein the controller is further configured to, or the method further includes: detecting whether the ventricular rhythm exceeds a selected ventricular rhythm threshold after initiating delivery of anti-tachycardia pacing therapy.

[0254] In illustrative embodiment 52, the apparatus or method of any of illustrative embodiments 49-51 is included, wherein the controller is further configured for, or the method further includes: monitoring for tachycardia in response to detecting a regular ventricular rhythm.

[0255] In illustrative embodiment 53, the device or method of any of illustrative embodiments 49-52 is included, wherein the controller is further configured for, or the method further includes: in response to detecting a ventricular rhythm exceeding a selected ventricular rhythm threshold, delivering electrical shock therapy using a separate device therapy.

[0256] In illustrative embodiment 54, the device or method of any of illustrative embodiments 49-53 is included, wherein the electroshock therapy includes delivering a signaling pulse to the left ventricle using a tissue piercing electrode.

[0257] In illustrative embodiment 55, the device or method of illustrative embodiment 54 is included, wherein the signaling pulse is configured to be detected by a separate medical device to trigger delivery of an electrical shock from the separate medical device to cardiac tissue.

[0258] In illustrative embodiment 56, the device or method of any of illustrative embodiments 49-54 is included, wherein the separate medical device is not connected to the implantable medical device by a metallic conductor.

[0259] Thus, various embodiments of VFA cardiac treatment are disclosed. Although reference is made herein to the accompanying set of drawings that form a part of the present disclosure, it will be understood by those of ordinary skill in the art that various adaptations and modifications of the embodiments described herein are within the scope of the present disclosure or do not depart from the scope of the present disclosure. For example, various aspects of the embodiments described herein may be combined with each other in various ways. Therefore, it should be understood that within the scope of the appended claims, the claimed invention may not be practiced as explicitly described herein.

[0260] It will be understood that each block of the block diagrams, and combinations of blocks, can be implemented by means for performing the functions shown.

[0261] All references and publications cited herein are hereby expressly incorporated by reference into this disclosure in their entirety, except to the extent they may directly contradict this disclosure.

[0262] Unless otherwise specified, all scientific and technical terms used herein have the common meanings in the art. The definitions provided herein are intended to facilitate understanding of certain terms frequently used herein and are not intended to limit the scope of the present disclosure.

[0263] Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as modified by the terms "exact" or "approximately." Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and the appended claims are approximations that may vary, for example, within the ordinary range of experimental error depending upon the desired properties sought by those skilled in the art utilizing the teachings disclosed herein.

[0264] The recitation of numerical ranges by endpoints includes all numbers within that range (e.g., from 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5) and any range within that range. As used herein, the term "up to" or "not greater than" a number (e.g., up to 50) includes that number (e.g., 50), and the term "not less than" a number (e.g., not less than 5) includes that number (e.g., 5).

[0265] The terms "coupled" or "connected" refer to elements being attached to each other directly (in direct contact with each other) or indirectly (with one or more elements attached therebetween). Either term may be modified by "operably" or "operably" (the two words are used interchangeably) to describe a coupling or connection that is configured to allow the components to interact to perform at least some function (e.g., an intracardiac medical device may be operably or operably coupled to an extravascular ICD for initiating shock therapy).

[0266] References to "one embodiment," "an embodiment," "certain embodiments," or "some embodiments," etc., mean that a particular feature, configuration, component, or characteristic described in conjunction with that embodiment is included in at least one embodiment of the present disclosure. Thus, the appearance of such abbreviations in various places throughout the text does not necessarily refer to the same embodiment of the present disclosure. Furthermore, particular features, configurations, components, or characteristics may be combined in any suitable manner in one or more embodiments.

[0267] The words "preferred" and "preferably" refer to embodiments of the present disclosure that may bring certain benefits in certain situations. However, other embodiments may also be preferred under the same or other situations. Further, the enumeration of one or more preferred embodiments does not mean that other embodiments are not useful, and is not intended to exclude other embodiments from the scope of the present disclosure.

[0268] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include embodiments with plural referents, unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term "or" is generally employed in its sense including "and / or" unless the content clearly dictates otherwise.

[0269] As used herein, "have / having", "include / including", and "comprise / comprising", etc. are used in their open sense, and generally mean "including but not limited to". It will be understood that "consisting essentially of", "consisting of", etc. are subsumed under "comprising", etc.

[0270] The term "and / or" means one or all of the listed elements or a combination of at least two of the listed elements.

[0271] The phrases “at least one of,” “including at least one of,” and “one or more of” accompanying a list refer to any one of the items in the list and any combination of two or more items in the list.

Claims

1. An implantable medical device comprising: A plurality of electrodes, the plurality of electrodes comprising: a tissue-piercing electrode that can be implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body into the basal region and / or septal region of the left ventricular myocardium of the patient's heart for at least one of delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart, and a right atrial electrode positionable within the right atrium for at least one of delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart; a therapy delivery circuit operably coupled to the plurality of electrodes for delivering cardiac therapy to a heart of the patient; sensing circuitry operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart; and a controller comprising processing circuitry operably coupled to the therapy delivery circuit and the sensing circuit, the controller being configured to: Perform at least one of the following: monitor the electrical activity of the right atrium using the right atrial electrode; and monitor the electrical activity of the left ventricle using the tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and central fiber body into the basal region and / or septal region of the left ventricular myocardium of the patient's heart; and Cardiac resynchronization pacing is delivered based on monitored electrical activity using at least the tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and central fibrous body into the basal and / or septal regions of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

2. The device according to claim 1, characterized in that The controller is further configured to perform: monitoring far-field electrical activity of the right ventricle using the right atrial electrode.

3. The device according to claim 1, characterized in that Delivering cardiac resynchronization pacing based on the monitored electrical activity using at least the tissue puncture electrode implanted from the triangle of Koch of the right atrium through the right atrial endocardium and central fiber body in the basal and / or septal regions of the left ventricular myocardium of the patient's heart to pace one or both ventricles comprises: sensing atrial events within the monitored electrical activity of the right atrium, and In response to sensed atrial events, pacing is delivered to one or both ventricles for providing cardiac resynchronization.

4. The device according to claim 1, characterized in that Delivering cardiac resynchronization pacing based on the monitored electrical activity using at least the tissue puncture electrode implanted from the triangle of Koch of the right atrium through the right atrial endocardium and central fiber body in the basal and / or septal regions of the left ventricular myocardium of the patient's heart to pace one or both ventricles comprises: sensing ventricular events from electrical activity monitored using the tissue-piercing electrodes; and In response to sensed ventricular events, pacing is delivered to one or both ventricles for providing cardiac resynchronization.

5. The device according to claim 4, characterized in that Delivering pacing to one or both ventricles in response to the sensed ventricular event includes delivering the pacing to one or both ventricles after a selected period of time has elapsed from the sensed ventricular event.

6. The device according to any one of claims 1 to 5, characterized in that The controller is further configured to perform: detecting atrial fibrillation and initiating a single chamber pacing mode.

7. The device according to any one of claims 1 to 5, characterized in that The controller is further configured to perform: receiving a trigger from a separate medical device in a triggered pacing mode.

8. The device according to any one of claims 1 to 5, characterized in that The controller is further configured to perform: delivering pacing in an asynchronous pacing mode.

9. The device according to any one of claims 1 to 5, characterized in that Further including: a housing extending from a proximal end region to a distal end region, wherein the right atrial electrode is leadlessly coupled to the housing and the tissue piercing electrode is leadlessly coupled to the distal end region of the housing, wherein the therapy delivery circuit, the sensing circuit, and the controller are positioned within the housing; as well as An optional fixation member extending from the housing, the fixation member configured to penetrate into the myocardium, wherein the fixation member extends from the distal end region of the housing toward a distal tip of the tissue piercing electrode.

10. The device according to any one of claims 1 to 5, characterized in that Further including: a housing, wherein the therapy delivery circuitry, the sensing circuitry, and the controller are positioned within the housing; as well as A lead is coupled to the housing and extends from the housing to a distal end region, wherein the tissue piercing electrode and the right atrial electrode are coupled to the distal end region of the lead.

11. The device according to any one of claims 1 to 5, characterized in that Further including: a housing, wherein the therapy delivery circuitry, the sensing circuitry, and the controller are positioned within the housing; a first lead coupled to the housing and extending from the housing to a first distal end region; as well as A second lead is coupled to the housing and extends from the housing to a second distal end region, wherein the tissue piercing electrode is coupled to the first distal end region of the first lead, and wherein the right atrial electrode is coupled to the second distal end region of the second lead.

12. The device according to any one of claims 1 to 5, characterized in that Further including: a housing, wherein the therapy delivery circuitry, the sensing circuitry, and the controller are positioned within the housing; a first lead coupled to the housing and extending from the housing to a first distal end region; a second lead coupled to the housing and extending from the housing to a second distal end region; as well as a third lead coupled to the housing and extending from the housing to a third distal end region, Wherein, the plurality of electrodes further include a right ventricular electrode, which is coupled to the third distal end region of the third lead for delivering cardiac therapy to the right ventricle of the patient's heart or sensing electrical activity of the right ventricle of the patient's heart, wherein the tissue puncture electrode is coupled to the first distal end region of the first lead, and wherein the right atrial electrode is coupled to the second distal end region of the second lead.

13. An implantable medical device comprising: a housing extending from a proximal end region to a distal end region; A plurality of electrodes, the plurality of electrodes comprising: a tissue-piercing electrode coupled to the distal end region of the housing without leads and implantable from the Koch triangle of the right atrium through the right atrial endocardium and the central fiber body into the basal region and / or septal region of the left ventricular myocardium of the patient's heart for delivering cardiac therapy to the left ventricle or sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart, and a right atrial electrode leadlessly coupled to the housing and positionable within the right atrium for delivering cardiac therapy to the right atrium of the patient's heart or sensing electrical activity of the right atrium of the patient's heart; a therapy delivery circuit within the housing and operably coupled to the plurality of electrodes for delivering cardiac therapy to a heart of the patient; sensing circuitry within the housing and operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart; and a controller comprising processing circuitry within the housing operably coupled to the therapy delivery circuitry and the sensing circuitry, the controller being configured to: Perform at least one of the following: monitor the electrical activity of the right atrium using the right atrial electrode; and monitor the electrical activity of the left ventricle using the tissue puncture electrode from the Koch triangle of the right atrium through the right atrial endocardium and central fiber body to the basal region and / or septal region of the left ventricular myocardium of the patient's heart; and Cardiac resynchronization pacing is delivered based on monitored electrical activity using at least the tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and central fibrous body into the basal and / or septal regions of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

14. An implantable medical device comprising: A plurality of electrodes, the plurality of electrodes comprising: a tissue-piercing electrode that can be implanted from the Koch triangle of the right atrium through the right atrial endocardium and the central fibrous body into the basal region and / or septal region of the left ventricular myocardium of the patient's heart for at least one of delivering cardiac therapy to the left ventricle and sensing electrical activity of the left ventricle in the basal region and / or septal region of the left ventricular myocardium of the patient's heart, and a right atrial motion detector positionable within the right atrium for sensing mechanical activity of the right atrium of the patient's heart; a therapy delivery circuit operably coupled to the plurality of electrodes for delivering cardiac therapy to a heart of the patient; sensing circuitry operably coupled to the plurality of electrodes for sensing electrical activity of the patient's heart; and a controller comprising processing circuitry operably coupled to the therapy delivery circuit and the sensing circuit, the controller being configured to: monitoring mechanical activity of the right atrium using the right atrial motion detector; and Cardiac resynchronization pacing is delivered based on the monitored mechanical activity of the right atrium using at least the tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and central fibrous body into the basal and / or septal regions of the left ventricular myocardium of the patient's heart to pace one or both ventricles.

15. A non-transitory computer-readable storage medium storing instructions that, when executed by one or more processing circuits, cause the one or more processing circuits to perform a method comprising: performing at least one of the following electrical activity monitoring: monitoring electrical activity of the right atrium of the patient's heart using a right atrial electrode; and monitoring the electrical activity of the left ventricle using a tissue puncture electrode implanted from the Koch triangle of the right atrium through the right atrial endocardium and central fibrous body into the basal region and / or septal region of the left ventricular myocardium of the patient's heart; as well as Cardiac resynchronization pacing, including pacing one or both ventricles, is delivered based on monitored electrical activity using at least the tissue puncture electrodes implanted from the Koch triangle of the right atrium through the right atrial endocardium and central fibrous body into the basal and / or septal regions of the left ventricular myocardium of the patient's heart.

16. The non-transitory computer-readable storage medium of claim 15, wherein: The method further includes monitoring far-field electrical activity of the right ventricle using the right atrial electrode.

17. The non-transitory computer-readable storage medium of claim 15, wherein: Delivering cardiac resynchronization pacing based on the monitored electrical activity using at least the tissue puncture electrode implanted from the triangle of Koch of the right atrium through the right atrial endocardium and central fiber body in the basal and / or septal regions of the left ventricular myocardium of the patient's heart to pace one or both ventricles comprises: sensing atrial events within the monitored electrical activity of the right atrium, and In response to sensed atrial events, pacing is delivered to one or both ventricles for providing cardiac resynchronization.

18. The non-transitory computer-readable storage medium of claim 15, wherein: Delivering cardiac resynchronization pacing based on the monitored electrical activity using at least the tissue puncture electrode implanted from the triangle of Koch of the right atrium through the right atrial endocardium and central fiber body in the basal and / or septal regions of the left ventricular myocardium of the patient's heart to pace one or both ventricles comprises: sensing ventricular events from electrical activity monitored using the tissue-piercing electrodes; and In response to sensed ventricular events, pacing is delivered to one or both ventricles for providing cardiac resynchronization.

19. The non-transitory computer-readable storage medium of claim 18, wherein: Delivering pacing to one or both ventricles in response to the sensed ventricular event includes delivering the pacing to one or both ventricles after a selected period of time has elapsed from the sensed ventricular event.

20. The non-transitory computer-readable storage medium according to any one of claims 15 to 19, wherein: The method further includes detecting atrial fibrillation and initiating a single chamber pacing mode.

21. The non-transitory computer-readable storage medium according to any one of claims 15 to 19, wherein: The method further includes receiving a trigger from a separate medical device in a triggered pacing mode.

22. The non-transitory computer-readable storage medium according to any one of claims 15 to 19, wherein: The method further includes delivering pacing in an asynchronous pacing mode.

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