Byosiver atrial detection using coronal sinus (CS) signals
A catheter-based system with electrodes in the coronary sinus analyzes intracardiac signals to determine the atrial flutter origin by comparing signal stability, addressing the inefficiencies and risks of current mapping methods.
Patent Information
- Application Number
- CN202380038004.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-05-02
- Filing Date
- 2023-04-20
- Publication Date
- 2024-12-13
AI Technical Summary
Existing methods for determining the origin of atrial flutter in the left or right atrium are time-consuming and risky, often requiring extensive mapping that may inadvertently puncture the septum, especially when the flutter originates in the right atrium.
A catheter with multiple electrodes is positioned in the coronary sinus, allowing electrodes to overlap both atria, and a processor analyzes intracardiac signals to identify the atrium of origin by comparing signal stability metrics, distinguishing between arrhythmogenic and bystander atria using correlation scores.
Enables rapid and confident identification of the atrial flutter source, reducing the need for extensive mapping and minimizing risks associated with septum puncture.
Smart Images
Figure CN119136738A_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates generally to electrophysiological (EP) sensing using a catheter, and particularly to EP sensing of atrial flutter using a catheter placed in the coronary sinus (CS). Background Art
[0002] Cardiac diagnostic and / or therapeutic techniques involving placement of a catheter in the coronary sinus have been previously proposed in the patent literature. For example, U.S. Patent Application Publication No. 2012 / 0172867 describes a system and method for treating cardiac arrhythmias. The system includes a position sensor in contact with a portion of cardiac tissue, and the analyzed position changes represent movement of the tissue. The system is configured to generate an indicator of the characteristics of the heart affected by the delivery of ablative energy to cardiac tissue in response to movement of the sensor over a period of time. In this way, the effectiveness and safety of cardiac tissue ablation for treating arrhythmias can be evaluated, and a post-ablation treatment plan can be determined. In an exemplary embodiment, a coronary sinus (CS) catheter can also be provided for collecting EP data associated with the heart, so that images of the geometry of the heart surface and related EP data can be generated. Because the coronary sinus is a relatively stable location, the CS catheter can also provide a position reference for comparing the position measurements of the mapping catheter with the position reference to compensate for cardiac motion. BRIEF DESCRIPTION OF THE DRAWINGS
[0003] The present disclosure will be more fully understood through the following detailed description of examples of the present disclosure in conjunction with the accompanying drawings, in which:
[0004] Figure 1 is a schematic illustration of a catheter-based electrophysiological (EP) sensing system according to an example of the present disclosure;
[0005] Figure 2 is placed in the coronary sinus (CS) according to an example of the present disclosure Figure 1 Schematic illustration of the catheter;
[0006] Figure 3A and Figure 3B is a collection of graphs of intracardiac EP signals from two cardiac cycles according to an example of the present disclosure, which are generated by placing a CS Figure 1 The catheter electrode is used to collect the
[0007] Figure 4 is a flow chart schematically illustrating a method for identifying an atrium of origin of atrial flutter according to an example of the present disclosure. DETAILED DESCRIPTION
[0008] Overview
[0009] Atrial flutter is an abnormal heart rhythm that occurs in the atria of the heart. When atrial flutter first occurs, it is often associated with tachycardia and falls into the category of supraventricular tachycardia (SVT). Although this rhythm most often occurs in individuals with cardiovascular disease or diabetes, it can also occur spontaneously in people with otherwise normal hearts. Atrial flutter is often an erratic rhythm and often degenerates into atrial fibrillation. Therefore, there is a need to treat atrial flutter.
[0010] It has been found that atrial flutter is often caused by a single reentrant wavefront in the left atrium (LA) or right atrium (RA), characterized by continuous cyclic activation of the atria, often around an anatomical barrier. Due to the reentrant nature of atrial flutter, the circuit causing atrial flutter can often be ablated. This is often done in the electrophysiology operating room by creating a ridge of scar tissue that crosses the path of the circuit causing atrial flutter. Therefore, as described above, isthmus ablation is a common treatment for typical atrial flutter.
[0011] When flutter is first diagnosed, it is often not obvious to the physician whether the flutter originates in the left or right atrium. While the origin of the flutter can be determined following EP mapping of both the left and right atria, this is time consuming and may also put patients with RA flutter at risk of puncturing the septum when navigating to the LA for mapping. Furthermore, if the flutter is in the RA, mapping the LA may not be necessary.
[0012] Examples of the present disclosure described herein provide a technique for acquiring and analyzing CS signals captured with a CS catheter to identify the atrium most likely to be the source of flutter. The CS signal may be a unipolar intracardiac (IC) electrogram (EGM) signal. The CS catheter has a plurality of electrodes and is positioned such that the electrodes extend over the left and right atria, including discrete electrode groups extending over each atrium.
[0013] Using a processor and algorithm, the repeatability of each set of IC signals in time can be independently monitored and compared (e.g., between templates of reference signals taken during periods of arrhythmia to be used as reference proarrhythmic signals for EP mapping) so that mapping will occur during periods when the heart exhibits arrhythmia, thereby giving clinical value to the procedure. The atria causing flutter are expected to show IC signals similar to the template, while IC EGM signals from bystander atria are expected to differ from the reference proarrhythmic signals.
[0014] In other words, a CS catheter having multiple electrodes is placed so that some of the electrodes overlap the LA of the heart and some of the electrodes overlap the RA of the heart. Using the EP signal from the CS catheter, the processor estimates a corresponding signal stability metric by the signal acquired by the electrode overlapping the LA and by the signal acquired by the electrode overlapping the RA. Therefore, a portion of the CS signal with high signal stability (e.g., high correlation) (whether distal or proximal) is most likely derived from the portion of the CS signal of the arrhythmogenic tissue atrium.
[0015] Furthermore, when the physician observes the CS signal, there is instability of the IC CS signal at the electrode portion overlapping the bystander atrium due to the unstable condition of the activation channel between the ventricles. At the same time (i.e., when the arrhythmia is active), the signal portion acquired by the CS electrode overlapping the arrhythmogenic atrium shows a high degree of repeatability (e.g., stability). Therefore, the physician is able to know with high confidence which atrium has abnormal tissue even before inserting the mapping catheter.
[0016] Typically, the processor is programmed in software containing specific algorithms that enable the processor to perform each of the processor-related steps and functions described above.
[0017] System Description
[0018] Figure 1 is a schematic illustration of a catheter 21 based electrophysiological (EP) sensing system 20 according to an example of the present disclosure. Figure 1 Illustration 15 of shows the general anatomy of the heart, and as can be seen, the right atrium collects deoxygenated blood from three sources, namely the superior vena cava (SVC), the inferior vena cava (IVC), and the CS which returns blood from the myocardium. In illustration 25, catheter 21 is inserted into CS 202 to collect IC EGM signals which may indicate atrial flutter originating from either RA or LA.
[0019] The catheter 21 includes a deflectable tip segment 40 mounted at the distal end of the shaft 22 of the catheter 21, wherein the deflectable tip segment 40 includes a plurality of electrodes 50. In the example described herein, the deflectable tip segment 40 is inserted into the CS 202 so that Figure 2 As described in , the distal portion of electrode 50 overlaps with the LA of heart 26 to acquire EP signals originating from the LA, while the proximal portion of electrode 50 overlaps with the RA of heart 26 to acquire EP signals originating from the RA. The IC EGM signal may be a single-pole signal measured between electrode 50 and surface electrodes 38, which are attached to the chest of patient 28 positioned on examination table 29 by wires passing through cable 37 in the exemplary system.
[0020] The proximal end of catheter 21 is connected to console 24, which includes interface circuitry 44. Electrodes 50 are connected by wires passing through shaft 22 to interface circuitry 44, where EP signals are received and processed (eg, digitized) and output to processor 41 in console 24 for analysis.
[0021] The processor 41 may further receive an electrical impedance signal measured between the electrode 50 and the surface electrode 38. A method for using the measured impedance to track the position of the electrode 50 is implemented in various medical applications, such as in the CARTO TM The present invention is implemented in a system and described in detail in U.S. Patent No. 8,456,182, which is assigned to the assignee of the present disclosure. This method is sometimes referred to as Advanced Catheter Localization (ACL). Console 24 drives display 27, which shows the tracked position and / or shape of deflectable tip segment 40 within heart 26. Various signals (such as EP signals) are stored in memory 46.
[0022] The processor 41 shown included in the console 24 is typically a general purpose computer with a suitable front end and interface circuitry 44 for receiving signals from the catheter 21 in the left atrium of the heart 26 and for controlling other components of the system 20. The processor 41 typically includes software in a memory 46 of the system 20 that is programmed to perform the functions described herein. The software may be downloaded to the computer in electronic form over a network, for example, or it may alternatively or additionally be provided and / or stored on a non-transitory tangible medium such as magnetic, optical, or electronic memory. Specifically, the processor 41 runs the software disclosed herein and included in the system 20. Figure 4 , which enables the processor 41 to perform the disclosed steps, as further described below.
[0023] Bystander atrial detection using CS signals
[0024] Figure 2 is placed in the coronary sinus (CS) according to an example of the present disclosure Figure 1 Schematic diagram of catheter 21. As can be seen in the figure, the distal portion 501 of electrode 50 overlaps with LA, while the proximal portion 502 of electrode 50 overlaps with RA. The electrode belonging to the distal portion 501 acquires local IC signals mainly associated with LA tissue, while the electrode belonging to the proximal portion 502 acquires local IC signals mainly associated with LA tissue.
[0025] Figure 3A and Figure 3Bis a collection of graphs of IC EGM signals from two cardiac cycles according to an example of the present disclosure, which are generated by placing a CS Figure 1 The electrodes of the catheter are used for collection.
[0026] exist Figure 3A , the distal portion 304 of the electrode overlaps with the LA, while the proximal portion 305 of the electrode overlaps with the RA. As can be seen, when comparing the template arrhythmogenic CS signal and the newly acquired signal, the signal from the distal portion 304 is highly uncorrelated (e.g., different). On the other hand, the signal from the proximal portion 304 is highly correlated between the two cardiac cycles. As described above, such a situation is highly indicative of atrial flutter originating in the RA.
[0027] like Figure 3B As can be seen in , which shows results from another patient, when the template arrhythmogenic CS signal is compared to the newly acquired CS signal, the signal from the distal portion 307 is highly uncorrelated (e.g., different). On the other hand, when the two cardiac cycles are compared, the signal from the proximal portion 306 is highly correlated (e.g., similar). Such a situation is highly indicative of atrial flutter originating from the LA.
[0028] The processor 41 can quantify the above observations by calculating separate correlation scores with the signals from the distal portion and the proximal portion. In one example, stability can be determined based on such correlation scores. To this end, the method disclosed in U.S. Patent Application Publication 2021 / 0169359 assigned to the assignee of the present application can be used: The processor applies a window of interest (WOI) to the IC EGM signal representing the entire cycle length of a single heartbeat. A pattern of interest (POI) is selected to include a portion of the WOI corresponding to the arrhythmia activation. A template POI is generated, which represents the arrhythmia activation. Subsequent electrical activity is received, weights are applied, and the subsequent electrical activity is compared to the template POI. A correlation score is generated.
[0029] In the present disclosure, such correlation scores for the electrode set associated with the left atrium are compared with the correlation scores for the electrode set associated with the right atrium. Based on this comparison, the atrium causing the flutter can be identified.
[0030] For example, processor 41 compares each portion of the correlation score to a predetermined score and, based on the comparison, may inform the user which atrium is the origin of the atrial flutter.
[0031] As an example, the above description relates to the use of correlations and correlation scores.In alternative examples, processor 41 may use any other suitable signal stability metric to quantify the signal stability of the electrode set associated with the right atrium relative to the electrode set associated with the left atrium.
[0032] Method for bystander atrial detection using CS signal
[0033] Figure 4 is a flow chart schematically illustrating a method for identifying the origin atrium of atrial flutter according to an example of the present disclosure. According to the example presented, the algorithm performs a process starting at the catheter placement step 402, where the physician 30 inserts, navigates, and places the catheter within the CS 202, with the distal portion 501 and the proximal portion 502 of the electrode 50 divided between the LA and the RA and covering the LA and the RA, respectively, as shown in FIG. Figure 2 The physician 28 controls the catheter 21 using a manipulator / handle 32 connected to the sheath 23 in which the shaft 22 is positioned.
[0034] Next, at EP signal acquisition step 404, the physician 30 acquires IC EGM signals at the SC using the catheter 21, as described above.
[0035] At a correlation score calculation step 406, processor 41 applies the above-described method to score the repeatability of the IC EGMS signals acquired by the distal and proximal portions of electrode 50 compared to the template arrhythmogenic signal.
[0036] At a score comparison step 408, the processor identifies that one atrium has a low correlation score and the other atrium has a high correlation score.
[0037] Based on the comparison, at a notification step 410 , processor 41 notifies the physician that the atrium with the high correlation score is the atrium identified as the source of atrial flutter.
[0038] For example, in the above step 408, when one of the signal stability metrics is above a first threshold and another of the signal stability metrics is below a second threshold, the processor indicates in step 410 the atrium corresponding to the highest of the signal stability metrics as the source of atrial flutter.
[0039] Figure 4 The example flow chart shown in is selected purely for conceptual clarity. In alternative examples, additional steps may be performed, such as the processor 41 acquiring a position signal using the electrode 50, and performing one or both of adjusting the placement of the catheter and verifying the stability of the placement of the catheter based on the position signal, and the user visually checking the signal on the display.
[0040] Example
[0041] Example 1
[0042] A method for identifying atrial flutter, the method comprising: placing a catheter (21) including a plurality of electrodes (50) in a coronary sinus (CS) (202) of a heart (26) of a patient (28) such that some of the electrodes (50) overlap with a left atrium (LA) of the heart and some of the electrodes (50) overlap with a right atrium (RA) of the heart. Acquiring intracardiac (IC) electrophysiological (EP) signals using the electrodes (50). Estimating corresponding signal stability metrics using the signals acquired by the electrodes overlapping the LA and the signals acquired by the electrodes overlapping the RA. When one of the signal stability metrics is above a first threshold and another of the signal stability metrics is below a second threshold, indicating the atrium corresponding to the highest of the signal stability metrics as a source of atrial flutter.
[0043] Example 2
[0044] The method of embodiment 1, wherein the signal stability metric comprises a correlation level relative to a corresponding reference IC signal.
[0045] Example 3
[0046] A method according to any one of embodiments 1 and 2, wherein the reference IC signal is acquired during an arrhythmia period of the heart (26).
[0047] Example 4
[0048] The method according to any one of embodiments 1 to 3, wherein the reference IC signal is a template signal.
[0049] Example 5
[0050] The method of any one of embodiments 1 to 4, wherein the reference IC signal is acquired during a previous cardiac cycle, and wherein a correlation level below the second threshold indicates instability of the IC signal between cardiac cycles.
[0051] Example 6
[0052] A method according to any one of embodiments 1 to 5, wherein the electrodes (50) are arranged in a linear array along the distal end of the catheter.
[0053] Example 7
[0054] A method according to any one of embodiments 1 to 6, and comprising using the electrode (50) to collect a position signal, and performing one or both of adjusting the placement of the catheter (21) and verifying the placement stability of the catheter based on the position signal.
[0055] Example 8
[0056] The method of any one of embodiments 1 to 7, wherein the IC EP signal is an IC electrogram (EGM) signal.
[0057] Example 9
[0058] An atrial flutter identification system includes a catheter (21) and a processor (41). The catheter (21) includes a plurality of electrodes (50), wherein the catheter is configured to be placed in a coronary sinus (CS) (202) of a heart (26) of a patient (28) such that some of the electrodes overlap with a left atrium (LA) of the heart and some of the electrodes overlap with a right atrium (RA) of the heart. The processor is configured to: (i) acquire intracardiac (IC) electrophysiological (EP) signals using the electrodes (50); (ii) estimate corresponding signal stability metrics using the signals acquired by the electrodes overlapping the LA and the signals acquired by the electrodes overlapping the RA; and (iii) when one of the signal stability metrics is above a first threshold and another of the signal stability metrics is below a second threshold, indicate an atrium corresponding to the highest of the signal stability metrics as a source of atrial flutter.
[0059] It should be understood that the above examples are cited by way of example, and the present disclosure is not limited to what is specifically shown and described above. On the contrary, the scope of the present disclosure includes combinations and sub-combinations of the various features described above and their variations and modifications, which will occur to a person skilled in the art when reading the above description and which are not disclosed in the prior art. The documents incorporated by reference into this patent application are considered an integral part of this application, unless any term defined in these incorporated documents conflicts with the definition explicitly or implicitly given in this specification, in which case only the definition in this specification shall be considered.
Claims
1. A method for identifying atrial flutter, the method comprising: placing a catheter comprising a plurality of electrodes in a coronary sinus (CS) of a patient's heart such that some of the electrodes overlap a left atrium (LA) of the heart and some of the electrodes overlap a right atrium (RA) of the heart; collecting intracardiac (IC) electrophysiological (EP) signals using the electrodes; estimating a corresponding signal stability metric by the signal acquired by the electrode overlapping the LA and by the signal acquired by the electrode overlapping the RA; as well as When one of the signal stability metrics is above a first threshold and another of the signal stability metrics is below a second threshold, the atrium corresponding to the highest of the signal stability metrics is indicated as a source of atrial flutter.
2. The method according to claim 1, wherein: The signal stability metric includes a correlation level relative to a corresponding reference IC signal.
3. The method according to claim 2, wherein: The reference IC signal is acquired during an arrhythmia period of the heart.
4. The method according to claim 2, wherein: The reference IC signal is a template signal.
5. The method according to claim 2, wherein: The reference IC signal is acquired during a previous cardiac cycle, and wherein a correlation level below the second threshold indicates instability of the IC signal between cardiac cycles.
6. The method according to claim 1, wherein: The electrodes are arranged in a linear array along the distal end of the catheter.
7. The method of claim 1, and comprising acquiring position signals using the electrodes, and performing one or both of adjusting placement of the catheter and verifying placement stability of the catheter based on the position signals.
8. The method according to claim 1, wherein: The IC EP signal is an IC electrogram (EGM) signal.
9. A system for identifying atrial flutter, the system comprising: a catheter comprising a plurality of electrodes, the catheter being configured to be placed in a coronary sinus (CS) of a patient's heart such that some of the electrodes overlap a left atrium (LA) of the heart and some of the electrodes overlap a right atrium (RA) of the heart; and A processor, the processor being configured to: collecting intracardiac (IC) electrophysiological (EP) signals using the electrodes; estimating a corresponding signal stability metric by the signal acquired by the electrode overlapping the LA and by the signal acquired by the electrode overlapping the RA; as well as When one of the signal stability metrics is above a first threshold and another of the signal stability metrics is below a second threshold, the atrium corresponding to the highest of the signal stability metrics is indicated as a source of atrial flutter.
10. The system according to claim 9, wherein: The signal stability metric includes a correlation level relative to a corresponding reference IC signal.
11. The system according to claim 10, wherein: The reference IC signal is acquired during an arrhythmia period of the heart.
12. The system according to claim 10, wherein: The reference IC signal is a template signal.
13. The system according to claim 10, wherein: The reference IC signal is acquired during a previous cardiac cycle, and wherein a correlation level below the second threshold indicates instability of the IC signal between cardiac cycles.
14. The system according to claim 9, wherein: The electrodes are arranged in a linear array along the distal end of the catheter.
15. The system according to claim 9, wherein: The processor is further configured to acquire a position signal using the electrodes, and to instruct, based on the position signal, to perform one or both of adjusting the placement of the catheter and verifying the placement stability of the catheter.
16. The system of claim 9, wherein: The IC EP signal is an IC electrogram (EGM) signal.