System for serial comparison of electrocardiograms

Abstract

Systems for detecting potential pacemaker capture loss in a surface electrocardiogram (ECG) signal are provided. In one example, a system includes a plurality of electrodes (RA, LA, RL, LL, V1, V2, V3, V4, V5, V6) configured to measure electrical potentials generated at a patient's skin, an electrode monitor (10) configured to generate an ECG signal from the electrical potentials, an interface (434), a memory (406) storing instructions, and at least one processor (404) configured to execute the instructions to obtain (504) a baseline ECG signal of the patient, obtain (702) a current ECG signal of the patient from the electrode monitor, determine that the patient has an electronic implant performing biventricular pacing based on the baseline ECG signal and / or the current ECG signal, compare (712, 714) the baseline ECG signal of the patient to the current ECG signal based on the determination, and indicate (722) a deterioration condition of the electronic implant through the interface based on the comparison and the determination.

Description

Technical Field

[0001] The embodiments of the subject matter disclosed herein relate to electrocardiography (ECG), and more specifically, to detecting potential pacemaker capture loss in ECG signals. Background Technology

[0002] Electrocardiogram (ECG) monitors are widely used to obtain medical (e.g., biopotential) signals containing information indicating electrical activity associated with a patient's heart and lung systems. To obtain these signals, ECG electrodes are applied to different locations on the patient's skin. After being positioned on the patient, the electrodes are connected to an ECG monitor via a set of ECG leads. The ECG signals obtained using the electrodes can be processed into pacing and / or biopotential signals, which can be evaluated by clinicians to diagnose or rule out various patient conditions such as acute myocardial infarction. Summary of the Invention

[0003] In one embodiment, a system includes: a plurality of electrodes configured to measure an electrical potential generated at the skin of a patient; an electrode monitor configured to generate an electrocardiogram (ECG) signal based on the electrical potential measured by the plurality of electrodes; an interface for communicating with a user; a memory storing instructions; and at least one processor configured to execute the stored instructions to: obtain a baseline ECG signal of the patient; obtain a current ECG signal of the patient from the electrode monitor; determine, based on the baseline ECG signal and / or the current ECG signal, that the patient has an electronic implant performing biventricular pacing; compare the patient's baseline ECG signal with the current ECG signal based on the determination that the electronic implant is performing biventricular pacing; and, based on the comparison and the determination that the electronic implant is performing biventricular pacing, indicate a deterioration condition of the electronic implant via the interface.

[0004] The above-described advantages, as well as other advantages and features, of this specification will become apparent, either alone or in connection with the accompanying drawings, from the following detailed description. It should be understood that the above summary is provided to present a simplified version of the selected concepts further described in the detailed description. This is not intended to identify key or essential features of the claimed subject matter, the scope of which is uniquely defined by the claims following the detailed description. Furthermore, the claimed subject matter is not limited to embodiments that address any of the disadvantages mentioned above or in any part of this disclosure. Attached Figure Description

[0005] A better understanding of the various aspects of this disclosure can be achieved by reading the following detailed description and referring to the accompanying drawings, in which:

[0006] Figure 1An implementation scheme for a diagnostic monitoring system connected to an electrode configuration suitable for collecting standard twelve-lead electrocardiograms is described;

[0007] Figure 2 The implementation scheme for the pacing system is described;

[0008] Figure 3 The implementation scheme for the data acquisition module is described;

[0009] Figure 4 This is a block diagram schematically illustrating a serial comparison system according to an embodiment of the present disclosure;

[0010] Figure 5 This is a flowchart illustrating a method for storing baseline ECG signals in an ECG database;

[0011] Figure 6 This is a flowchart illustrating a method for obtaining a patient's current ECG signal;

[0012] Figure 7 This is a flowchart illustrating a method for performing a serial comparison of the current ECG signal with respect to a baseline ECG signal to detect capture loss;

[0013] Figure 8 An exemplary pacing signal that can be evaluated to detect biventricular pacing is shown;

[0014] Figure 9 An exemplary combination of pacing signals and biopotential signals is shown; and

[0015] Figure 10 A set of bioelectric potential signals that can be evaluated to detect the loss of capture is shown. Detailed Implementation

[0016] Cardiac resynchronization therapy (CRT) relies on a special type of pacemaker to treat heart failure. These electronic cardiac implants, known as biventricular pacemakers, generate multiple artificial stimuli designed to optimize the uniformity of left ventricular wall contraction and blood expulsion, thereby making the heart pump more effectively.

[0017] Unfortunately, artificial stimulation can fail for a variety of reasons. One such reason is called “capture loss,” which means that the implant can send electrical impulses down the lead line into the heart muscle, but the muscle is ultimately not sufficiently stimulated to depolarize and contract. CRT is particularly prone to capture loss for leads placed along the free wall of the left ventricle (LV). The reason LV leads are more prone to capture failure is that the right ventricle (RV) and LV leads are attached to the heart using different methods. In the case of the RV, the lead is threaded or harpooned into the ventricular wall at the apex of the RV. However, in the case of the LV, the lead is not threaded anywhere. Instead, the lead is simply placed in the venous return of the coronary circulation. Any clots that form due to the presence of the LV lead can therefore return to the right atrium instead of traveling to the brain (which would happen if the LV were fixed to the wall of the LV). However, the trade-off is that due to the fragile nature of the coronary veins, LV leads cannot be threaded or harpooned into the heart muscle, and therefore, LV leads can easily displace.

[0018] When LV lead shifts, patients who may have been successfully treated for heart failure may suddenly develop symptoms such as shortness of breath, extreme fatigue, and / or weakness—symptoms that initially led to CRT deployment. Given the ominous change in the patient's symptoms, they often do not contact the electrophysiologist who initially implanted the biventricular pacemaker but instead go immediately to the emergency room (ED). Unfortunately, EDs do not have the same equipment as electrophysiologists to diagnose malfunctions caused by the implant itself or by the failure to capture artificial stimulation generated by the implant. For example, inquiring about an implant typically requires a proprietary inquiry stick and programmer (e.g., a workstation) specific to the particular manufacturer of the implant. Without these tools, care providers in EDs or other general healthcare settings may not be able to determine the type of implant present in a patient, let alone whether it exhibits a particular type of deterioration. Therefore, treating patients presenting with cardiac-related symptoms can be time-consuming and difficult, and sometimes can lead to an inappropriate initial diagnosis, potentially jeopardizing patient care.

[0019] Therefore, according to the embodiments disclosed herein, an indication of capture loss can be obtained solely using the surface ECG signal output without the need for a dedicated implant programmer or other equipment. In the absence of a pacemaker programmer, potential or probable capture loss during biventricular pacing can be identified by confirming that the patient not only has an electronic implant capable of CRT (e.g., biventricular pacing), but that the electronic implant repeatedly triggers during the QRS complex (e.g., confirming biventricular pacing is occurring), and further confirming that the patient's QRS complex is wider or points in a different direction than the QRS complex observed during the initial deployment of the CRT implant.

[0020] To detect whether biventricular pacing is occurring, a high-frequency ECG system can be used because the multiple artificial stimuli used to synchronize the squeezing motion of the left ventricle occur so closely that they cannot be detected by a conventional ECG. Furthermore, a serial comparison procedure can be performed to assess changes in the patient's QRS morphology in the presence of biventricular pacing. If the patient's QRS duration changes significantly, the system will indicate this change, which may be related to the operation of the CRT implant. Additionally, if the QRS axis changes significantly, the system will indicate this change, which may also be related to the operation of the CRT implant.

[0021] Figure 1 An exemplary monitoring system for monitoring a patient's heart is shown, which includes an electronic implant with a surface ECG signal obtained via electrodes coupled to a data acquisition module. Figure 2 An exemplary electronic implant is shown inside a patient's body. Figure 3 A detailed block diagram of the data acquisition module is shown, including components for identifying pacing signals (e.g., pacemaker pulses). Figure 8 The signals shown, as well as biopotential signals in surface ECG signals, such as Figure 9 and Figure 10 The component shown is a bioelectric potential signal. Figure 4 An exemplary ECG system is shown, configured to perform a serial comparison of pacing signals and biopotential signals to diagnose capture loss, which can be based on... Figures 5 to 7 The method shown in the figure is used to perform the operation.

[0022] Figure 1 A monitoring system 10 connected to a patient 12 is depicted. In an alternative embodiment, the monitoring system 10 may also be a diagnostic system to assist clinicians in interpreting physiological data. The monitoring system 10 is connected to the patient 12 via multiple electrodes (labeled RA, LA, RL, LL, V1, V2, V3, V4, V5, and V6). The electrodes are typically placed in standard anatomical positions according to the standard acquisition of a 12-lead electrocardiogram (ECG). A 12-lead ECG utilizes four limb electrodes (RA, LA, RL, LL) and six precordial electrodes (V1, V2, V3, V4, V5, and V6). Differential voltages are obtained between two or more of these electrodes to obtain a lead or projection through the heart, along which the electrical characteristics of the heart are measured. While a 12-lead ECG is shown herein, it should be understood that the monitoring system 10 may include an appropriate number of leads, such as six, without departing from the scope of this disclosure.

[0023] Patient 12's heart 14 generates electrical pulses 16 at regular intervals. As the electrical pulses 16 propagate through the heart, they cause the heart's muscle tissue to contract. The resulting electrical potential generated at the patient's skin due to the propagation of this electrical pulse through the myocardial tissue is measured by each electrode in the electrode array and represented by each ECG lead in the ECG lead array.

[0024] Typically, when cardiac tissue is damaged or diseased, the heart generates or transmits electrical impulses improperly and cannot contract properly. In such cases, an electronic implant 18, such as a pacemaker or defibrillator, is placed inside the patient's body. The electronic implant 18 generates its own electrical impulses 20 to stimulate the tissues of the heart 14, causing the heart 14 to contract properly.

[0025] The electrodes placed on patient 12 are electrical transducers, and therefore collect all electrical energy at the electrode locations and provide the sensed electrical signals to the data acquisition module 22 of monitoring system 10. Thus, data acquisition module 22 acquires not only the electrocardiographic pulses 16, but also the electrical implant pulses 20, as well as electrical noise from any number of sources within and around the patient. Electrical noise may include electromagnetic noise from human sources, electrical pulses from other medical devices used to provide care to the patient, and electrical pulses from other biopotentials generated by the patient, such as muscle contractions (EMG) and / or brain waves (EEG).

[0026] The electrodes can be attached to the skin of the patient 12 in a manner that senses any biopotential signal generated by the patient 12's heart 14 and a pacing signal generated by the electronic implant 18. Since the pacing signal is an electrical signal applied to the patient's heart, the electrodes will combine the biopotential signal generated by the heart to sense pacing stimulation. Therefore, the combined signal sensed by the electrodes includes both the biopotential signal from the heart and the pacing signal from the electronic implant 18.

[0027] In the currently disclosed embodiments, the data acquisition module 22 may be included in an electrode monitor (also referred to herein as an ECG monitor) that receives the sensed combined signal and converts it from an analog signal to a digital signal. In these embodiments, the data acquisition module / ECG monitor is a high-bandwidth module, wherein the combined signal sensed by the electrodes is digitized at a high sampling rate compared to standard ECG monitoring techniques. Standard ECG monitoring techniques typically achieve digitization sampling rates between 500 Hz and 1000 Hz. In the high-bandwidth data acquisition module / ECG monitor, the combined signal is sampled at a rate of 50 kHz or higher. The combined signal may be sampled at a rate between 50 kHz and 75 kHz. Alternatively, the combined signal may be sampled at a rate higher than that of standard ECG monitoring techniques but lower than that of the disclosed high-bandwidth ECG monitoring techniques. These alternative sampling rates may be any sampling rate higher than 1 kHz and lower than 50 kHz. In some embodiments, the high bandwidth of the combined signal provides increased signal data, which facilitates signal processing as described further in detail herein. Therefore, Figure 1 The system shown includes: a plurality of electrodes configured to measure an electrical potential generated at the patient’s skin; and an electrode monitor (e.g., an ECG monitor) configured to generate an electrocardiogram (ECG) signal (e.g., via data acquisition module 22) based on the electrical potential measured by the plurality of electrodes.

[0028] Figure 2 An example of a pacing system 210 appearing in a patient's body is depicted. The pacing system 210 is... Figure 1 A non-limiting example of an electronic implant 18. The pacing system 210 includes an implantable pacemaker 212. Multiple pacemaker leads 214 extend from the pacemaker 212. The pacemaker leads 214 extend from the pacemaker 212 into the patient's heart 216. Each pacemaker lead 214 extends to a different portion of the heart 216 and terminates at a pacemaker electrode. The RA pacemaker lead 218 extends to the right atrium (RA) and terminates at the RA pacemaker electrode 220. The LV pacemaker lead 222 extends to the left ventricle (LV) and terminates at the LV pacemaker electrode 224. The RV pacemaker lead 226 extends to the right ventricle (RV) and terminates at the RV pacemaker electrode 228.

[0029] Although the placement of the three pacemaker electrodes has been described herein, it should be understood that the pacemaker electrodes may be positioned at alternative locations on the heart, and patients may be treated using one or more pacemaker electrodes in the pacing system 210, without the need for or limitation to the arrangement having the three pacemaker electrodes as described above.

[0030] Pacemaker electrodes (220, 224, 228) are attached to the myocardium (muscle tissue) of the heart using a fixation mechanism. In the case of RA pacemaker electrode 220 and RV pacemaker electrode 228, the fixation mechanism is typically a helical device that secures the electrode and creates a favorable electrical connection between the pacemaker electrode and the myocardium. Alternatively, as is commonly used with LV pacemaker electrode 224, the electrode is not attached to the myocardium itself; instead, the LV pacemaker lead 222 is placed in the coronary sinus vein, and tension in the LV pacemaker lead 222 or other elastic properties of the LV pacemaker lead 222 holds the LV pacemaker electrode 224 in place. This can be used as an alternative to other fixation mechanisms to prevent damage to the tissue or blood vessel where the lead and electrode are located.

[0031] The pacemaker 212 monitors the electrical activity of the heart 216 and analyzes these biopotential signals to detect abnormalities in the morphology and / or timing of the biopotential signals from the heart. Based on the detected abnormalities, the pacemaker 212 can deliver electrical pulses to one or more pacemaker electrodes (220, 224, 228) via pacemaker leads 214.

[0032] Another challenge to achieving optimal performance of the pacing system 200 is the dynamic and adverse environment within the patient's body, which is highly susceptible to foreign objects. The body, particularly the heart 216, is constantly in motion, and the body's immune system is designed to isolate and destroy any foreign objects, such as the implanted pacing system 210. Therefore, pacing system malfunctions due to damaged and / or incomplete electrical connections are common. Due to the dynamic conditions within the patient's body, the pacemaker leads 214 are constantly shifting. Furthermore, the body's immune system weakens the insulation on the leads over time. Both factors make the leads prone to breakage. The constant movement of the pacing system 200 also makes the pacemaker electrodes susceptible to microscopic and macroscopic displacement when the electrode fixation mechanism is pulled away from the heart tissue or otherwise removed from electrical contact with the target physiological placement.

[0033] The goal is to easily detect the presence of pacing system malfunctions, identify the causes of the malfunctions, and remedy the causes in order to provide appropriate pacing therapy to the patient. A non-limiting list of pacing system malfunctions includes lead breakage, insulation defects, micro-displacement, macro-displacement, battery depletion, and pacemaker hardware defects.

[0034] The aforementioned failures can manifest as various variations in the morphology of the detected combined signal, which includes biopotential signals collected from one or more surface electrodes and pacemaker signals (electrocardiogram (ECG)). A non-limiting list of such pacing system complexities includes sensing failure, capture failure, and inappropriate rate. Sensing failure occurs when the pacemaker fails to sense a response of the myocardium to electrical pacing stimulation. Capture failure occurs when the pacemaker cannot generate a stimulation pulse sufficient to stimulate the myocardium. Inappropriate rate is characterized by the pacemaker generating stimulation pulses at a rate that is too slow or too fast.

[0035] Figure 3 A more detailed implementation of the data acquisition module 22 is described. The data acquisition module 22 receives physiological data from electrodes and processes the physiological data along two data processing paths. A first data processing path 24 is used to isolate and process the ECG component of the raw physiological data. This biopotential signal is typically the most important and / or clinically relevant data obtained in such systems. The biopotential signal (in this case, ECG data) provides the most information about the patient's physiological condition and bodily function. The ECG data / biopotential signal can be isolated from the physiological data via an isolation biopotential circuit 26. As mentioned above, the frequency content of ECG data (e.g., biopotential signal) is typically between 0.5 Hz and 150 Hz; therefore, the isolation biopotential circuit 26 may include a low-pass filter. Next, an analog-to-digital converter (ADC) 28 can be used to digitize the isolated biopotential signal. An exemplary sampling frequency for the biopotential signal could be 2 kHz; however, this is not intended to limit the frequency at which ECG can be sampled. Finally, the digitized biopotential signal from the first data processing path 24 can be provided to a controller or CPU 36 for further data processing as explained herein.

[0036] Physiological data is also processed by data acquisition module 22 along a second data processing path 30. The purpose of the second data processing path is to isolate and enhance therapeutic event signals (e.g., pacing signals or pacemaker pulses), which are provided by the electronic implant 18 in the embodiments described herein. This can be achieved by isolating therapeutic event circuitry 32. As mentioned above, the bandwidth of the therapeutic event signal can be much larger than the bandwidth of the previously described biopotential signal. Therefore, isolating therapeutic event circuitry 32 may include a bandpass filter having a passband between 250 Hz and 15 kHz. However, the aforementioned passband is merely exemplary and is not intended to limit the type of filter or passband that can be implemented in embodiments of isolating therapeutic event circuitry 32.

[0037] Next, the filtered therapeutic event signal can be digitized by ADC 34. Since the therapeutic event signal can have a much higher frequency content than the biopotential signal, ADC 34 can sample at a much higher frequency than ADC 28. As an example sampling rate, ADC 34 can sample at 75 kHz; however, this sampling rate is not intended to limit the range of sampling rates that ADC 34 can use. Finally, the digitized therapeutic event signal (e.g., a digitized pacing signal) is provided to CPU 36 for further processing as disclosed herein.

[0038] In an alternative embodiment of the data acquisition module 22, a single multiplexer (not depicted) can be used to sample each electrode, eliminating the need for multiple data processing paths. In embodiments that do not use a multiplexer, each physiological data lead may require a first data processing path 24 and a second data processing path 30. The use of a multiplexer can reduce implementation and component costs by eliminating the redundancy required to process all physiological data simultaneously.

[0039] refer to Figure 4 An ECG system 400 including a serial comparison system 402 is illustrated according to an exemplary embodiment. In some embodiments, at least a portion of the serial comparison system 402 is included in a device (e.g., an edge device, server, etc.) communicatively coupled to the monitoring system 10 via a wired and / or wireless connection. In some embodiments, at least a portion of the serial comparison system 402 is included in a separate device (e.g., a server) that can receive ECG data from the monitoring system 10 or from a storage device storing ECG data. The serial comparison system 402 may be operatively / communically coupled to a user input device 432 and one or more clinical devices 434.

[0040] The serial comparison system 402 includes a processor 404 configured to execute machine-readable instructions stored in non-transitory memory 406. Processor 404 may be a single-core or multi-core processor, and the program executing on it may be configured for parallel or distributed processing. In some embodiments, processor 404 may optionally include individual components distributed across two or more devices, which may be remotely located and / or configured for collaborative processing. In some embodiments, one or more aspects of processor 404 may be virtualized and executed by a remotely accessible, networked computing device configured in a cloud computing configuration.

[0041] Non-transitory memory 406 may store comparison module 407 configured to execute a serial comparison procedure, wherein a current ECG for a specific patient is received at serial comparison system 402, which initiates a serial comparison procedure. Comparison module 407 retrieves records of previous ECGs (also referred to as baseline ECGs) for the specific patient stored in ECG database 426 and presents the previous ECGs for comparison with records of the current ECG for the same patient. Additional details regarding the serial comparison procedure for detecting capture loss are described below. Figure 7 Provided.

[0042] In some embodiments, nontransitory memory 406 may include components included in two or more devices that are remotely located and / or configured for coordinated processing. In some embodiments, one or more aspects of nontransitory memory 406 may include remotely accessible networked storage devices configured in a cloud computing configuration.

[0043] User input device 432 may include one or more of the following: a touchscreen, keyboard, mouse, touchpad, motion-sensing camera, or other devices configured to enable a user to interact with and manipulate data within the serial comparison system 402. In some examples, user input device 432 is included as part of monitoring system 10 and / or one or more clinical devices 434.

[0044] The serial comparison system 402 can be configured to send reports and / or other communications to the monitoring system 10 and / or one or more clinical devices 434. The one or more clinical devices 434 may include digital pagers, smartphones, tablets, laptops, fax machines, printers, hospital information systems for accounting and clinical reporting, workstations, and / or other servers or computing devices on the network to which the serial comparison system 402 is connected. The one or more clinical devices 434 may include interfaces for communicating with users, such as display devices utilizing virtually any type of technology. In some embodiments, the display device may include a computer monitor and may display ECG data and / or reports about the ECG data generated by the comparison module 407. In some embodiments, the serial comparison system 402 may include interfaces for communicating with users, such as display devices, enabling the transmission of ECG data and / or reports about the ECG data generated by the comparison module 407 without intermediate devices.

[0045] In some examples, the serial comparison system 402 and / or ECG database 426 may be communicatively coupled to one or more remote implant services 424. The serial comparison system 402 and / or ECG database 426 may be communicatively coupled to one or more remote implant services 424 via a Health LevelSeven International (HL7) interface (or another type of interface that enables secure connections between clinical devices according to established standards), such that the serial comparison system 402 and / or ECG database 426 can communicate with one or more remote implant services 424 via the HL7 protocol. One or more remote implant services 424 may be maintained by an electronic implant manufacturer and / or electrophysiologist's clinic and may include information about electronic implants (e.g., pacemakers) implanted in a patient, such as the time of last configuration and implant configuration for each implant.

[0046] It should be understood that Figure 4 The serial comparison system 402 shown is for illustrative purposes and not for limiting purposes. Another suitable serial comparison system may include more, fewer, or different components.

[0047] Figure 5 This is a flowchart illustrating an exemplary method 500 for storing baseline ECG signals in an ECG database according to an embodiment of the present disclosure. Method 500 is referenced to... Figures 1 to 4 The system and components described herein are for informational purposes only; however, it should be understood that method 500 can be implemented with other systems and components without departing from the scope of this disclosure. Method 500 can be implemented according to systems and components stored such as... Figure 4 The serial comparison system 402 executes instructions from the non-transitory memory of the computing device. Although method 500 is described for a single patient, it should be understood that method 500 can be performed for each of multiple patients, such that the baseline ECG signal is stored in the ECG database for each patient for whom the ECG signal is obtained.

[0048] At 502, a command is received to store one or more baseline ECG signals from the patient. This command may include a request sent from an ECG display (e.g., monitoring system 10) indicating that the patient's baseline ECG signal has been acquired and will be sent to a serial comparison system for storage in an ECG database. In other examples, an explicit command may be omitted, and the serial monitoring system may determine to store the baseline ECG signal upon receiving an ECG signal from monitoring system 10. In some examples, the baseline ECG signal may be the patient's first ECG signal sent to the serial comparison system. In other examples, the baseline ECG signal may be an updated ECG signal sent to the serial comparison system after an electronic implant has been placed in the patient or an existing electronic implant has been reconfigured. In a further example, the baseline ECG signal may be an updated ECG signal sent to the serial comparison system after a relatively long period of time since a previous baseline ECG signal was stored for the patient (e.g., after six months or a year). In any of these examples, the baseline ECG signal may represent a baseline (e.g., normal or expected) function of the patient's heart with which future ECG signals can be compared and / or the baseline configuration of the patient's electronic implant.

[0049] At position 504, the patient's ECG signal is received. The ECG signal may include digitized ECG recordings from one or more leads of the ECG, such as 12 digitized ECG recordings obtained from a 12-lead ECG (e.g., from monitoring system 10). In some examples, the ECG signal may be digitized at a high sampling rate such as 50 kHz or higher. In such examples, the signal from one or more of the 12 leads may be as described above regarding... Figure 3The signal is processed as described (e.g., by a bandpass filter with a passband between 250 Hz and 15 kHz and digitized at a high sampling rate) to isolate pacing signals that may indicate electrical pulses originating from an electronic implant (e.g., a pacemaker) present in the patient. Therefore, the ECG signal received at 504 may include pacing signals, as indicated at 506. Regardless of the type of ECG system used to obtain the ECG signal, the ECG signal received at 504 may include a biopotential signal, as indicated at 508. In at least some examples, the biopotential signal may indicate electrical pulses generated by the patient's heart and may be isolated using a low-pass filter and digitized at a sampling rate of 2 kHz. For example, the biopotential signal may be a typical ECG waveform that may include a P wave during atrial depolarization, a QRS complex during ventricular depolarization, and a T wave during ventricular repolarization. This may result in five definable points within the waveform: P, Q, R, S, and T. Various ECG features may include different intervals detected within the biopotential signal via one or more ECG analysis algorithms (which may be applied during serial comparisons as described below), such as PR intervals (e.g., measured from the beginning of the P wave to the beginning of the QRS complex), RR intervals (e.g., measured from the first R wave to the second R wave of the subsequent heartbeat), QT intervals (e.g., measured from the beginning of the QRS complex to the end of the T wave), etc.

[0050] At point 510, the pacing signal and / or biopotential signal are stored as the patient's baseline ECG signal in an ECG database (such as ECG database 426). Therefore, when an ECG signal is captured using a high-sampling-rate ECG monitor, the baseline ECG signal may include the baseline biopotential signal (for each lead of the ECG monitor) and optionally may also include the baseline pacing signal (for each lead of the ECG monitor). The baseline ECG signal may be tagged with patient identification information (e.g., medical record ID) to facilitate retrieval of the baseline ECG signal at a later date (if indicated), which will be explained in more detail below. Furthermore, if any interpretation is performed on the baseline ECG signal (e.g., via monitoring system 10), such as statements indicating the discovery of anomalies, annotations of ECG complexes in the baseline ECG signal, etc., those statements or annotations may also be sent to a serial comparison system and stored in the ECG database along with the baseline ECG signal.

[0051] In some examples, as indicated at 512, the baseline ECG signal can be updated if information is received from an implant service, such as one or more remote implant services 424. For example, the implant service may store the current configuration of the implant in the patient's body (e.g., whether the implant has been configured to perform biventricular pacing or a different type of pacing, the number, interval, and / or duration of pacing pulses, etc.), and may send the current configuration of the implant in response to a request from the serial comparison system. In some examples, once communication between the serial comparison system and the implant service has been established for the patient, the implant service may push notifications about the patient to the serial comparison system, such as notifications indicating that the patient's implant configuration has changed. In other examples, the serial comparison system may occasionally query the implant service to determine if any changes have been made to the patient's implant configuration. In examples where the patient's implant configuration has changed, the changes to the configuration may be stored in the ECG database along with the baseline ECG signal. Method 500 then returns.

[0052] Figure 6 This is a flowchart illustrating an exemplary method 600 for obtaining a patient's current ECG signal according to an embodiment of the present disclosure. Method 600 is referenced to... Figures 1 to 4 The system and components described herein are for informational purposes only; however, it should be understood that method 600 may be implemented with other systems and components without departing from the scope of this disclosure. Method 600 may be executed according to instructions stored in the non-transitory memory of an ECG monitor, such as monitoring system 10.

[0053] At 602, the patient's current ECG signal is acquired. As described above, the ECG signal may include digitized ECG recordings from one or more leads of the ECG, such as 12 digitized ECG recordings obtained from a 12-lead ECG (such as from the electrodes and electrode monitors of the monitoring system 10). At least in some examples, the ECG recordings may be digitized at a high sampling rate. At 604, method 600 optionally includes identifying and recording a pacing signal in the current ECG signal, which may be as described above regarding... Figure 3 and Figure 5 The method is executed as explained above. When an ECG signal is acquired using an ECG monitor capable of digitizing the signal at a high sampling rate, a pacing signal can be identified. At 606, method 600 includes identifying and recording a biopotential signal in the current ECG signal, which can be performed as described above regarding... Figure 5 The interpretation is as follows. In this way, ECG signals can be processed to generate biopotential signals representing electrical impulses in the patient's heart and pacing signals representing impulses from the implant in the patient (when available).

[0054] At 608, method 600 determines whether a serial comparison of the current ECG signal is requested or instructed. A serial comparison may include a comparison between the patient's current ECG signal (e.g., a pacing signal and / or biopotential signal) and one or more baseline ECG signals of the patient collected at an earlier time to identify any changes from the baseline ECG signal to the current ECG signal that may indicate the patient and / or implant status. In some examples, a serial comparison may be performed in response to a request from a clinician (e.g., via user input entered into the ECG monitor). In other examples, a serial comparison may be performed automatically, such as whenever an ECG signal is obtained using the ECG monitor. If no serial comparison is requested, method 600 proceeds to 610 to display, evaluate, and / or save the current ECG signal without comparing the current ECG signal to a previous baseline ECG signal. In some examples, the current ECG signal may be evaluated to determine if there is a possible loss of capture of the electronic implant, even when no baseline ECG is available. For example, if the QRS duration is wide (e.g., wider than the average QRS duration) and the pacing signal indicates the presence of an electronic implant performing biventricular pacing, capture loss may be suspected, but it may not be confirmed at a certain level of confidence if the QRS duration was not previously measured after the electronic implantation. Then method 600 returns.

[0055] If a serial comparison is requested, method 600 proceeds to 612 to send the current ECG signal to the serial comparison system for further evaluation, which will be discussed below. Figure 7 A more detailed explanation follows. The current ECG signal transmitted at 612 may include pacing and biopotential signals, and may also include patient identification information (e.g., medical record ID). In some examples, any analysis of the current ECG signal performed by the ECG monitor may be transmitted along with the current ECG signal. Method 600 then ends.

[0056] Figure 7 This is a flowchart illustrating an exemplary method 700 for performing a serial comparison on a current ECG signal according to an embodiment of the present disclosure. Method 700 is referenced to... Figures 1 to 4 The system and components described herein are for informational purposes only; however, it should be understood that method 700 can be implemented with other systems and components without departing from the scope of this disclosure. Method 700 can be implemented according to systems and components stored such as... Figure 4 The serial comparison system 402 executes instructions from the non-transitory memory of the computing device.

[0057] At position 702, the patient's current ECG signal is received, such as in... Figure 6The ECG signal is sent at point 612. At point 704, method 700 determines whether the patient has a baseline ECG signal stored in (or in communication with) the ECG database of the serial comparison system, such as the baseline ECG signal obtained according to method 500 and / or the baseline ECG signal obtained via implant service. As described above, the current ECG signal may include a tag or header containing patient identification information, and the patient identification information may be used to query the ECG database to determine whether the patient's baseline ECG signal is stored in the ECG database. If the patient does not have a baseline ECG signal stored in the ECG database (e.g., if the query does not return any baseline ECG signal associated with the patient stored in the ECG database), method 700 proceeds to 706 to output a notification that a serial comparison cannot be performed. This notification may be configured to be displayed on a display device, such as with Figure 4 A display device associated with one of the clinical devices in clinical device 434. In some examples, even when a serial comparison cannot be performed, the serial comparison system is still able to assess features in the current ECG signal (e.g., the width of the QRS complex) and compare that feature with the overall mean or other known expected values ​​to determine potential patient conditions, as indicated at 708. In some examples, when the baseline ECG signal is not stored in the patient's ECG database, the current ECG signal can be stored as the baseline ECG signal. Method 700 then ends.

[0058] If the patient does have a baseline ECG signal stored in the ECG database, the baseline ECG signal is retrieved from the database and evaluated by the serial comparison system to determine if the patient has (or at least previously had) an electronic implant, and if the patient has an electronic implant, a baseline pacing configuration for the implant is determined. Determining the baseline pacing configuration helps narrow down possible patient or implant conditions, which can accelerate the process of identifying the most probable patient or implant condition and reduce the processing load on the serial comparison system by reducing the number of biopotential and pacing signal characteristics that can be evaluated to determine the most probable patient or implant condition.

[0059] Specifically, a patient's baseline ECG signal can be evaluated to determine if biventricular pacing is detected, as indicated at 710. Biventricular pacing can be detected by evaluating the pacing signal of the patient's baseline ECG signal and / or based on any statements stored with the baseline ECG signal (e.g., implant configuration determined from implant services). Biventricular pacing can be defined by outputting at least two implant pulses per cardiac cycle (e.g., at least two pulses during a QRS complex), including pulses to the right ventricle and pulses to the left ventricle. Biventricular pacing can be identified by recognizing pacemaker pulses in the pacing signal of the baseline ECG signal and superimposing (or otherwise aligning) the pacemaker pulses to the biopotential signal of the baseline ECG signal to determine when each pacemaker pulse occurs (within a cardiac cycle). In some examples, in addition to evaluating the baseline pacing signal or as an alternative, the presence of an electronic implant and its associated pacing configuration can be determined by evaluating the current ECG signal (e.g., the current pacing signal).

[0060] If biventricular pacing is not detected, method 700 proceeds to 712 to perform a serial comparison of the current ECG signal to detect one or more patient / implant conditions. For example, the biopotential signal of the current ECG signal may be compared to the biopotential signal of the baseline ECG signal to determine whether any changes in ST-segment elevation have occurred from the baseline signal to the current ECG signal and / or whether new Q waves are present in the current ECG signal, which could be a possible sign of acute myocardial infarction. Furthermore, in some examples, when biventricular pacing is not detected, a first number of features of the current biopotential signal may be compared to corresponding features of the baseline biopotential features. In some examples, the first number of features may be evaluated in a first order.

[0061] If biventricular pacing is detected at 710, a serial comparison system can evaluate the baseline signal and the current ECG signal to determine whether the patient's implant is potentially exhibiting capture loss, where the implant delivers electrical pulses down the lead lines to the myocardium, but the muscle is ultimately not adequately stimulated to depolarize and contract. To determine whether the implant is potentially exhibiting capture loss, method 700 includes comparing one or more characteristics of the baseline pacing signal with one or more corresponding characteristics of the current pacing signal at 714. The one or more characteristics of the pacing signal being evaluated may include the timing of the pacemaker pulses (e.g., time between each pulse), the pulse duration of each pacemaker pulse, the shape of each pacemaker pulse, etc. Once the implant is installed and properly configured, the shape of the pacemaker pulses and the timing between each pacemaker pulse should remain constant unless the implant is reconfigured by the implant installer. If one or more of the characteristics have changed from the baseline pacing signal to the current pacing signal, depending on which characteristics have changed, the one or more changed characteristics may indicate capture loss. For example, if the pacemaker pulse changes in duration or shape relative to the baseline pacemaker signal in the current pacing signal, the change in the pacemaker pulse can indicate a loss of capture.

[0062] Additionally, the biopotential signal can be evaluated to determine whether the implant may potentially exhibit capture loss. Therefore, at 716, method 700 includes comparing one or more features of the baseline biopotential signal with one or more corresponding features of the current biopotential signal. The one or more features of the evaluated biopotential signal may be selected based on determining that the implant is performing (or is intended to) perform biventricular pacing. The one or more features of the biopotential signal evaluated when biventricular pacing is detected may include a second number of features. The second number of features may be less than the first number of features evaluated when biventricular pacing is not detected, and / or the second number of features may be evaluated in a different order than the first number of features.

[0063] One or more features selected for evaluation may include the morphology of the QRS complex, such as its duration and electrical axis. If the QRS duration changes significantly (e.g., the duration of the QRS complex in the current biopotential signal is longer by a threshold amount or more than the duration of the QRS complex in the baseline biopotential signal, such as 10%–25% or more), the serial comparison system will indicate the change in QRS duration, and this change may be correlated with the goodness of implant operation. Additionally, if the QRS axis changes significantly (e.g., from normal to left-biased), the serial comparison system will indicate the change in QRS axis, and this change may be correlated with the goodness of implant operation. In some examples, the T axis may be evaluated in addition to the morphology of the QRS complex. In some examples, when biventricular pacing is detected, QRS duration and QRS axis may be evaluated before any other features, which may be the opposite of when biventricular pacing is not detected (e.g., where one or more other features may be evaluated before QRS duration and QRS axis).

[0064] At 718, method 700 includes determining whether one or more of the features have changed by at least a threshold amount, said one or more features include one or more features of the current pacing signal and / or one or more features of the current bioelectrical potential signal, as explained above. If none of the evaluated features have changed by at least a threshold amount, method 700 proceeds to 720 to indicate that no capture loss was detected and stores that indication in the ECG database.

[0065] If at least one of the features has changed by a threshold amount (e.g., if the QRS duration has increased by at least 10% or at least 25% relative to the QRS duration in the baseline biopotential signal), method 700 proceeds to 722 to indicate that a possible capture loss has been detected and stores the indication (along with the current ECG signal) in an ECG database. Furthermore, in some examples, this indication can be transmitted to the user via an interface (e.g., a serial comparison system or a display device of a clinical device), which can be performed once a final report is generated (as explained below) and / or once a possible capture loss is detected. At 724, if indicated, a serial comparison of other features in the current ECG signal can be performed. For example, other biopotential features / complexes can be evaluated to determine if there are any other changes in the current ECG signal relative to the baseline ECG signal. In some examples, if at least one feature has changed in a manner indicating a capture loss, the additional features evaluated may differ from those when no capture loss was indicated; for example, fewer additional features may be evaluated. In some examples, if a potential loss of capture is detected, a final report indicating the detection of a potential loss of capture can be generated without performing further analysis of the ECG signal. This can expedite notification of potential loss of capture and reduce any further delays in the diagnosis and treatment of patients.

[0066] Once all serial comparisons have been performed, a final report can be generated. When the serial comparison system generates a report for the patient after all indicative features of the current ECG signal have been evaluated, the report can indicate whether capture loss was detected or not (based on whether one or more features, as determined at 718, have changed) and the report can be sent to a clinical device, where it can be output for display, stored in an electronic medical record database, etc.

[0067] Therefore, method 700 can integrate capture loss analysis into a serial comparison procedure that compares multiple features of the patient's current biopotential signal with corresponding features of the patient's baseline biopotential signal acquired at an earlier time point. By using serial comparison to assess the presence or absence of capture loss, patients with a wider QRS duration than normal at implantation time (when the heart is pacing as expected) may not be indicated as potentially exhibiting capture loss, thus avoiding false negative diagnoses. Furthermore, determining whether biventricular pacing is occurring and whether a possible capture loss is detected can lead to cascading changes to subsequent assessments performed as part of the serial comparison, reducing the number of features assessed and the total amount of time required for assessment, thereby improving patient outcomes. For example, if biventricular pacing is detected in the patient's current pacing signal, additional assessments that could be performed to diagnose other implant problems (such as implant power problems, lead deterioration, problems that only occur when using a single-chamber pacing implant, etc.) can be omitted to accelerate the serial comparison procedure. Furthermore, when biventricular pacing is detected and a change in the patient's QRS morphology (e.g., a wide QRS complex) indicative of potential capture loss is detected via a serial comparison with the patient's baseline ECG signal, the confidence level of the patient exhibiting capture loss may be higher than when the patient's QRS complex is identified as wider than average but the patient does not have a baseline ECG signal for comparison. Therefore, the final report generated via the serial comparison disclosed herein can indicate a higher level of confidence regarding potential capture loss when a baseline ECG signal is used for comparison, compared to when only the current ECG signal is analyzed.

[0068] Furthermore, although method 700 has been described herein as first identifying whether the patient's implant is performing biventricular pacing and then evaluating features in the biopotential signal indicating capture loss, features in the biopotential signal can be evaluated first. If capture loss is a possible condition (e.g., due to a wide QRS complex), capture loss can be confirmed (or indicated at a higher confidence level) by confirming that the patient's implant is performing biventricular pacing. Conversely, if a wide QRS complex is detected, capture loss can be ruled out by confirming that the patient does not have an implant or that the patient's implant is not configured to perform biventricular pacing.

[0069] Figures 8 to 10 An example is shown that can be evaluated by a serial comparison system to determine whether there are ECG signal characteristics of capture loss. Figure 8An example of a pacing signal 800, for instance, that can be extracted from a baseline ECG signal, is shown. The pacing signal 800 includes a first pacing signal 810, which represents a sensed voltage as a function of time. The first pacing signal 810 can represent an isolated and digitized pacing signal obtained from a lead of the ECG. The first pacing signal 810 includes a plurality of pacemaker pulses, including a first pulse 812, a second pulse 814, a third pulse 816, and a fourth pulse 818. Each pacemaker pulse can be identified based on its amplitude and timing relative to an event in the corresponding biopotential signal (as described below). Figure 9 (As explained). For example, the first pulse 812 and the third pulse 816 can be identified as atrial pulses, while the second pulse 814 and the fourth pulse 818 can be identified as right ventricular pulses.

[0070] The pacing signal 800 also includes a first magnified view 820 of the first pulse 812 and a second magnified view 830 of the second pulse 814, each magnified view showing the voltage as a function of time. The time scale of each of the first magnified view 820 and the second magnified view 830 may be shorter than the time scale of the first pacing signal 810, such as a duration of 7 milliseconds relative to the 1.8-second duration of the first pacing signal 810.

[0071] Various features can be identified in the first pacing signal 810, which can be used to determine the pacing configuration of the implant and to compare with future ECG signals. For example, a first duration D1 can be determined between the first pulse 812 and the second pulse 814, a second duration D2 can be determined between the second pulse 814 and the third pulse 816, a third duration D3 can be determined between the first pulse 812 and the third pulse 816, and so on. Furthermore, the pulse duration of each pulse can be determined, such as the pulse duration D4 shown for the first pulse 812, the shape of each pulse (e.g., tilt angle / duration, discharge / recharge duration and shape, etc.), pulse amplitude, and / or other characteristics.

[0072] Figure 9An example of a combined ECG signal 900 is schematically illustrated, comprising detected pacemaker pulses 904 superimposed on an exemplary biopotential signal 902. The biopotential signal can be isolated and digitized as described above and can represent the biopotential signal from one lead of the ECG. The pacemaker pulses 904 are indicated by dashed lines such as line 906, the amplitude and direction of which indicate the approximate amplitude and polarity of the voltage signal of each pulse. Each pulse can be positioned on the biopotential signal 902 to show when each pulse occurs relative to the biopotential signal. Furthermore, the biopotential signal 902 can be analyzed to identify various characteristics, such as the duration of the QRS complex, which begins at the start of the Q wave, spans the R wave, and terminates at the end of the S wave.

[0073] Figure 10 An exemplary set of biopotential signals 1000, which can be evaluated by a serial comparison system according to the method 700 described above, is shown. The set of biopotential signals 1000 includes a current biopotential signal 1010 and a baseline biopotential signal 1020, which are shown over similar durations (e.g., on the same time scale).

[0074] Various characteristics of the current biopotential signal 1010 can be compared with corresponding characteristics of the baseline biopotential signal 1020 to determine whether the implant in the patient exhibits capture loss. For example, a QRS complex can be identified in each biopotential signal, and the duration of the QRS complex in the current biopotential signal 1010 can be compared with the duration of the QRS complex in the baseline biopotential signal 1020. Figure 10 As shown, the duration of the QRS complex in the current biopotential signal 1010 is significantly longer (e.g., at least 25% longer) than the duration of the QRS complex in the baseline biopotential signal 1020. An increase in the duration of the QRS complex can indicate capture loss, while a change in the opposite direction (e.g., a decrease in the duration of the QRS complex) may not indicate capture loss. Because a wide QRS complex can indicate other potential problems besides capture loss (e.g., bundle branch block, hyperkalemia, and other issues), the identification of a wide QRS complex, combined with knowledge that the patient has an implant configured to perform biventricular pacing, can help a serial comparison system suggest implant capture loss as a potential patient / implant condition.

[0075] Therefore, the serial comparison system disclosed herein can store a record of a patient's surface ECG when the implant (e.g., an implant configured to provide CRT) is first deployed or whenever the implant is reprogrammed. This record can be used as a marker of correct implant function, including the number of stimuli and the time intervals between stimuli, and how the QRS looks when all stimuli are correctly captured. The stored ECGs can be obtained using an ECG monitor at a medical facility, and / or specific ECG records can be obtained from a pacemaker laboratory (e.g., implant service) during implant deployment or reconfiguration. ECG records from the pacemaker laboratory can be tagged so that the serial comparison system can refer to these ECG records for comparison.

[0076] The advantage of using serial comparison to detect capture loss is that it allows for the differentiation of implant deterioration / failure (and especially capture loss) from other implants or patient conditions using only surface ECG recordings without requiring the patient or clinician to know about the implant or pacing configuration. This can accelerate diagnosis and patient care and reduce the processing burden on the computing device performing the serial comparison by reducing the number of features of the surface ECG signal that need to be evaluated.

[0077] This disclosure also provides support for a system comprising: a plurality of electrodes configured to measure potentials generated at the skin of a patient; an electrode monitor configured to generate an electrocardiogram (ECG) signal based on the potentials measured by the plurality of electrodes; an interface for communicating with a user; a memory storing instructions; and at least one processor configured to execute the stored instructions to: obtain a baseline ECG signal of the patient; obtain a current ECG signal of the patient from the electrode monitor; determine, based on the baseline ECG signal and / or the current ECG signal, that the patient has an electronic implant performing biventricular pacing; compare the patient's baseline ECG signal with the current ECG signal based on the determination that the electronic implant is performing biventricular pacing; and, based on the comparison and the determination that the electronic implant is performing biventricular pacing, indicate a degradation status of the electronic implant via the interface. In a first example of the system, obtaining the baseline ECG signal includes retrieving the baseline ECG signal from a database, and wherein the current ECG signal is acquired after the baseline ECG signal. In a second example of the system, the first example is optionally included, wherein the baseline ECG signal includes a baseline pacing signal and a baseline biopotential signal, and wherein determining that the patient has an electronic implant performing biventricular pacing includes determining that the patient has an electronic implant performing biventricular pacing based on the baseline pacing signal. In a third example of the system, one or both of the first and second examples are optionally included, wherein the current ECG signal includes a current pacing signal and a current biopotential signal, and wherein determining that the patient has an electronic implant performing biventricular pacing includes determining that the patient has an electronic implant performing biventricular pacing based on the current pacing signal. In a fourth example of the system, one or more or each of the first to third examples is optionally included, wherein comparing the patient's baseline ECG signal with the current ECG signal includes: identifying the baseline QRS duration in the baseline ECG signal; identifying the current QRS duration in the current ECG signal; and comparing the current QRS duration with the baseline QRS duration. In a fifth example of the system, optionally including one or more or each of the first to fourth examples, indicating a deterioration includes indicating a deterioration in response to the current QRS duration being longer than the baseline QRS duration by at least a threshold amount. In a sixth example of the system, optionally including one or more or each of the first to fifth examples, comparing the patient's baseline ECG signal with the current ECG signal includes: identifying the baseline QRS axis in the baseline ECG signal; identifying the current QRS axis in the current ECG signal; and comparing the current QRS axis with the baseline QRS axis. In a seventh example of the system, optionally including one or more or each of the first to sixth examples, indicating a deterioration includes indicating a deterioration in response to the current QRS axis differing from the baseline QRS axis by at least a threshold amount.In the eighth example of the system, one or more or each of the first to seventh examples may be optionally included, indicating a deterioration condition including indicating that the electronic implant exhibits a possible loss of capture.

[0078] This disclosure also provides support for a serial comparison system comprising: a non-transitory memory storing instructions and a processor, wherein the processor, when executing the instructions, is configured to: acquire a patient's current ECG signal; acquire a patient's baseline ECG signal from a database; determine that the patient has a pacemaker performing biventricular pacing based on a pacing signal extracted from the baseline ECG signal or the current ECG signal; compare one or more biopotential features of the baseline ECG signal with one or more corresponding biopotential features of the current ECG signal; select the one or more biopotential features based on determining that the pacemaker is performing biventricular pacing; and indicate whether the pacemaker exhibits a possible capture loss condition based on the comparison. In a first example of the system, the one or more biopotential features include QRS duration and / or QRS axis. In a second example of the system, optionally including the first example, indicating that the pacemaker exhibits a possible capture loss condition based on the comparison includes indicating that the pacemaker exhibits a possible capture loss condition based on a difference of at least a threshold amount between the QRS duration and / or QRS axis of the current ECG signal and the corresponding QRS duration and / or QRS axis of the baseline ECG signal. In a third example of the system, optionally including one or both of the first and second examples, the processor is further configured, upon execution of instructions, to compare the baseline ECG signal with the current ECG signal by comparing one or more biopotential features of the baseline ECG signal with one or more corresponding biopotential features of the current ECG signal, and / or by comparing one or more distinct biopotential features of the baseline ECG signal with one or more corresponding biopotential features of the current ECG signal, if the patient does not have a pacemaker performing biventricular pacing. In a fourth example of the system, optionally including one or more or each of the first to third examples, the processor is further configured, upon execution of instructions, to determine, based on pacing signals extracted from the baseline ECG signal or the current ECG signal, that the patient has a pacemaker but the pacemaker is not performing biventricular pacing, and to indicate whether the patient or pacemaker has one or more other conditions, without indicating whether the pacemaker exhibits capture loss.

[0079] This disclosure also provides support for a method comprising: obtaining a patient's baseline electrocardiogram (ECG) signal; obtaining the patient's current ECG signal; determining, based on the baseline ECG signal and / or the current ECG signal, that the patient has an electronic implant undergoing biventricular pacing; comparing the patient's baseline ECG signal with the current ECG signal; and indicating a deterioration of the electronic implant based on the comparison and determination that the electronic implant is undergoing biventricular pacing. In a first example of the method, the current ECG signal includes a current pacing signal and a current bioelectrical potential signal, the baseline ECG signal is obtained from a database and includes a baseline pacing signal and a baseline bioelectrical potential signal, comparing the current ECG signal with the baseline ECG signal includes comparing the current pacing signal with the baseline pacing signal and comparing the current bioelectrical potential signal with the baseline bioelectrical potential signal, and indicating a deterioration of the patient's electronic implant based on the comparison includes indicating a deterioration of the patient's electronic implant based on each comparison in the comparison. In a second example of the method, optionally including the first example, indicating the degradation of the electronic implant based on each comparison in the comparison includes: identifying that the electronic implant is configured to perform biventricular pacing based on a comparison of the current pacing signal with a baseline pacing signal; identifying changes in one or more features of the current biopotential signal relative to one or more corresponding features of the baseline biopotential signal; and indicating the degradation of the electronic implant based on identifying that the electronic implant is configured to perform biventricular pacing and based on identifying changes in one or more features of the current biopotential signal. In a third example of the method, optionally including one or both of the first and second examples, the one or more features of the current biopotential signal include one or more of the QRS duration and the QRS axis. In a fourth example of the method, optionally including one or more or each of the first to third examples, identifying changes in one or more features of the current biopotential signal relative to one or more corresponding features of the baseline biopotential signal includes identifying an increase in the QRS duration of the current biopotential signal relative to the QRS duration of the baseline biopotential signal. In a fifth example of the method, one or more or each of the first to fourth examples may be included, indicating the deterioration of the electronic implant including indicating possible loss of capture of the electronic implant.

[0080] When describing elements of various embodiments of this disclosure, the terms “an,” “a,” and “the” are intended to refer to one or more of these elements. The terms “first,” “second,” etc., do not indicate any order, quantity, or importance, but are used to distinguish one element from another. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that additional elements may exist in addition to the listed elements. As used herein, the terms “connected to,” “coupled to,” etc., indicate that an object (e.g., a material, element, structure, component, etc.) may be connected to or coupled to another object, regardless of whether the object is directly connected to or coupled to the other object, or whether one or more intervening objects exist between the object and the other. Furthermore, it should be understood that references to “an embodiment” or “an embodiment” of this disclosure are not intended to be construed as excluding the existence of additional embodiments that also include the referenced features.

[0081] In addition to any modifications previously indicated, those skilled in the art can devise many other variations and alternative arrangements without departing from the spirit and scope of this description, and the appended claims are intended to cover such modifications and arrangements. Therefore, although the information has been described above in a specific and detailed manner in conjunction with what is currently considered to be the most practical and preferred aspects, it will be apparent to those skilled in the art that many modifications can be made without departing from the principles and concepts set forth herein, including but not limited to changes in form, function, mode of operation, and use. Likewise, as used herein, in all respects, examples and embodiments are intended to be illustrative only and should not be construed as restrictive in any way.

Claims

1. A system for monitoring a patient's heart, the system comprising: Multiple electrodes configured to measure the potential generated at the patient's skin; An electrode monitor configured to generate an electrocardiogram (ECG) signal based on the potential measured by the plurality of electrodes; An interface used for communicating with the user; The memory stores instructions; At least one processor, the at least one processor being configured to execute stored instructions to: Obtain the patient's baseline ECG signal, which is based on the patient's previous ECG. The patient's current ECG signal is obtained from the electrode monitor; Based on the baseline ECG signal and / or the current ECG signal, it is determined that the patient has an electronic implant that is performing biventricular pacing; Based on the determination that the electronic implant is performing biventricular pacing, the patient's baseline ECG signal is compared with the current ECG signal; as well as Based on comparison and determination that the electronic implant is performing biventricular pacing, the degradation status of the electronic implant is indicated through the interface.

2. The system of claim 1, wherein obtaining the baseline ECG signal comprises retrieving the baseline ECG signal from a database, and The current ECG signal is acquired after the baseline ECG signal.

3. The system of claim 1, wherein the baseline ECG signal comprises a baseline pacing signal and a baseline biopotential signal, and wherein determining that the patient has an electronic implant performing biventricular pacing comprises determining that the patient has an electronic implant performing biventricular pacing based on the baseline pacing signal.

4. The system of claim 1, wherein the current ECG signal includes a current pacing signal and a current biopotential signal, and wherein determining that the patient has an electronic implant performing biventricular pacing includes determining that the patient has an electronic implant performing biventricular pacing based on the current pacing signal.

5. The system of claim 1, wherein comparing the patient's baseline ECG signal with the current ECG signal comprises: Identify the baseline QRS duration in the baseline ECG signal; Identify the current QRS duration in the current ECG signal; And compare the current QRS duration with the baseline QRS duration.

6. The system of claim 5, wherein indicating the degradation includes indicating the degradation in response to the current QRS duration being longer than the baseline QRS duration by at least a threshold amount.

7. The system of claim 1, wherein comparing the patient's baseline ECG signal with the current ECG signal comprises: Identify the baseline QRS electrical axis in the baseline ECG signal; Identify the current QRS axis in the current ECG signal; and compare the current QRS axis with the baseline QRS axis.

8. The system of claim 7, wherein indicating the degradation condition includes indicating the degradation condition in response to the current QRS axis differing from the baseline QRS axis by at least a threshold amount.

9. The system of claim 1, wherein indicating the degradation condition includes indicating that the electronic implant exhibits a possible loss of capture.

10. A method for monitoring a patient's heart, the method comprising: Obtain the patient's current ECG signal; Obtain the patient's baseline ECG signal, which is based on the patient's previous ECG. Based on the baseline ECG signal and / or the current ECG signal, it is determined that the patient has an electronic implant that is performing biventricular pacing; Compare the current ECG signal with the baseline ECG signal; as well as The patient's electronic implant deterioration is indicated by comparing and determining whether the electronic implant is performing biventricular pacing.

11. The method of claim 10, wherein the current ECG signal comprises a current pacing signal and a current biopotential signal, wherein the baseline ECG signal is obtained from a database and comprises a baseline pacing signal and a baseline biopotential signal, wherein comparing the current ECG signal with the baseline ECG signal comprises comparing the current pacing signal with the baseline pacing signal and comparing the current biopotential signal with the baseline biopotential signal, and wherein indicating the deterioration of the patient's electronic implant based on the comparisons and determining that the electronic implant is performing biventricular pacing comprises indicating the deterioration of the patient's electronic implant based on each comparison in the comparisons and determining that the electronic implant is performing biventricular pacing.

12. The method of claim 11, wherein indicating the degradation status of the electronic implant based on each comparison in the comparison comprises: The electronic implant is identified as being configured to perform biventricular pacing based on a comparison of the current pacing signal with the baseline pacing signal. Identify changes in one or more features in the current biopotential signal relative to one or more corresponding features in the baseline biopotential signal; as well as The degradation of the electronic implant is indicated by recognizing that the electronic implant is configured to perform biventricular pacing and by recognizing changes in one or more features of the current biopotential signal.

13. The method of claim 12, wherein the one or more features in the current biopotential signal include one or more of the QRS duration and the QRS electrical axis.

14. The method of claim 13, wherein identifying changes in one or more features in the current biopotential signal relative to one or more corresponding features in the baseline biopotential signal comprises identifying an increase in the QRS duration in the current biopotential signal relative to the QRS duration of the baseline biopotential signal.

15. The method of claim 12, wherein indicating the deterioration of the electronic implant includes indicating possible loss of capture of the electronic implant.

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