Intraoperative automated pericardial fluid monitoring using intracardiac ultrasound (ICE)
The system automates pericardial effusion detection using an intracardiac ultrasound probe with an orientation sensor, addressing the need for manual intervention in existing methods by providing real-time alerts and ensuring timely detection.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- BIOSENSE WEBSTER (ISRAEL) LTD
- Filing Date
- 2025-12-17
- Publication Date
- 2026-06-30
AI Technical Summary
Existing methods for detecting pericardial effusion during cardiac procedures require users to interrupt the workflow for manual visual confirmation, leading to potential delays and reliance on user expertise, which can compromise timely detection.
A system that uses an intracardiac ultrasound probe with an integrated orientation sensor to track the probe's position and orientation, enabling real-time automated detection and alerting of pericardial effusion by comparing ultrasound images to a baseline, thereby facilitating immediate response actions.
Enables rapid and automated detection of pericardial effusion, reducing the risk of delayed identification and ensuring timely intervention by providing real-time alerts based on predefined thresholds.
Smart Images
Figure 2026108596000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure generally relates to imaging of the anatomical structures of the human body, and more particularly to real-time monitoring of the anatomical structures of the heart using an ultrasound (US) probe.
Background Art
[0002] Pericardial effusion (PE) is commonly seen in cardiac catheterization procedures such as electrophysiological mapping and electrical ablation. Causes of excessive pericardial fluid include extensive intracardiac catheter manipulation and ablation, the need for more than one transseptal puncture, and the need for systemic anticoagulation. Severe PE can lead to hemodynamic decompensation and life-threatening cardiac tamponade.
[0003] Monitoring the undesirable effects of catheter procedures on the anatomical structures of the heart has been previously proposed in the patent literature. For example, U.S. Patent No. 9,833,165 describes monitoring cardiac ablation for detecting pericardial hematoma by repeatedly acquiring magnetic resonance imaging (MRI) data including the pericardium, measuring the pericardium by analyzing the MRI data set, determining that the measurements of the pericardium in successive MRI data sets are different, and reporting a change in the configuration of the pericardium in response to that determination.
[0004] The present disclosure will be more fully understood from the following detailed description of examples of the present disclosure in conjunction with the drawings.
Brief Description of the Drawings
[0005] [Figure 1] FIG. is a schematic diagram of a probe-based ultrasound (US) imaging, electrophysiological mapping, and electrical ablation system according to an example of the present disclosure. [Figure 2A]These are schematic ultrasound images of pericardial effusion (PE) obtained by orientation tracked by the US probe shown in Figure 1, in the example of the present disclosure, representing mild (Figure 2A), moderate (Figure 2B), and severe (Figure 2C) cases. [Figure 2B] These are schematic ultrasound images of pericardial effusion (PE) obtained by orientation tracked by the US probe shown in Figure 1, in the example of the present disclosure, representing mild (Figure 2A), moderate (Figure 2B), and severe (Figure 2C) cases. [Figure 2C] These are schematic ultrasound images of pericardial effusion (PE) obtained by orientation tracked by the US probe shown in Figure 1, in the example of the present disclosure, representing mild (Figure 2A), moderate (Figure 2B), and severe (Figure 2C) cases. [Figure 3] This flowchart schematically illustrates a method for automatically monitoring pericardial effusion in real time by analyzing US ultrasound images, as shown in Figure 2, according to an example of this disclosure. [Modes for carrying out the invention]
[0006] overview Pericardial effusion (PE) may occur during probe-based clinical procedures performed inside the cardiac chamber, such as electrophysiological mapping or electrical ablation.
[0007] To detect PE in a timely manner using conventional methods, users (e.g., physicians) need to intermittently view the anatomical structures of the heart to confirm PE, for example by using intracardiac echography (ICE) images, which interrupts the workflow of clinical cardiac procedures. Typically, users who are not experts in US imaging are required to stop catheterization to visually confirm the PE condition.
[0008] If users need to interrupt their workflow, PE identification may be delayed. Furthermore, rapid identification may depend on user preferences and abilities. For example, users may not have the expertise to acquire similar (e.g., similar views) ICE images over time and / or to accurately compare PE levels from captured images, even if they are examined in a timely manner.
[0009] The examples of the disclosure described herein provide techniques for enabling users to quickly initiate response actions, such as automatically detecting PEs in real time and alerting the user.
[0010] The system used in the disclosed technique monitors the PE status in real time and notifies the user when a threshold is exceeded and / or when it increases significantly from the baseline value. A position tracking system using an orientation tracking ICE catheter (and optionally position tracking as well) allows the system processor to compare images acquired from similar orientations.
[0011] For example, the disclosed technique includes the following steps, the key steps of which are performed in real time, thereby avoiding any delay in the detection of adverse events. - Record baseline pericardial fluid status and US probe orientation during initial cardiac ICE scanning. - Use a position tracking system to save the orientation of baseline recordings of ICE ultrasound images. - Repeatedly acquire further ultrasound images of the pericardial cavity with the same orientation (up to tolerance) to enable analysis of at least one image with the same ICE ultrasound image orientation as baseline. - Monitor the pericardial cavity (fluid level) by comparing the image to previously acquired images. In one example, the processor analyzes pixel intensity changes to estimate the fluid areas within the ultrasound image. - Notify the user of PE detection.
[0012] In another example, the processor compares the measured width of the pericardial fluid space to a threshold width without requiring a baseline value.
[0013] System Description Figure 1 is a schematic diagram of a probe-based ultrasound (US) imaging, electrophysiological mapping, and electrical ablation system 10, as illustrated in the present disclosure.
[0014] System 10 includes a multi-arm catheter 14 which is percutaneously inserted by a physician 24 through the patient's vascular system into a target lumen or vascular structure of the heart 12.
[0015] As shown in inset 25, the physician 24 brings the distal end effector 40, fitted onto the shaft 22 of the catheter 14, into contact with a target site within the heart 12, such as the wall 47 of the left atrium 45 (after the effector 40 has been inserted via transseptal puncture 146).
[0016] The physician 24 operates the system 10 using electrodes 26 distributed across multiple arms 16 in an expandable distal end effector 40 to sense intracardiac electrophysiological signals or apply electrical ablation at a target cardiac site.
[0017] The physician may insert an intracardiac ultrasound (US) probe 60, comprising a 2D ultrasound array 65 and an integrated orientation sensor 63 (optionally, the sensor 63 is also a position sensor), into the heart 12 at the beginning or at any time during the procedure. Optionally, and preferably, the sensor 63 is a magnetic-based sensor including a magnetic coil for sensing orientation and optionally three-dimensional (3D) position. In another example, the array 65 may be a 1D array producing a fan view at a given orientation.
[0018] The integrated sensor 63 of the US probe 21 is pre - aligned with the array 65 of US probes. For an integrated location sensor, the spatial coordinates of all voxels in the imaged intracardiac cavity are known. Specifically, the sensor 63 is configured to output a first signal indicating the location and orientation of the ultrasonic transducer array 65 inside the heart 26.
[0019] During the procedure, the console 24 receives an orientation signal from the sensor 63 in response to the magnetic field from the external magnetic field generator 32. The magnetic field generator 32 is placed at a known position on the position pad 25 outside the patient 23. These orientation signals indicate the orientation of the ultrasonic array 65 in the coordinate system of the position - tracking system. If the magnetic sensor includes position capabilities, this system can track its position in addition to its orientation.
[0020] Details of the magnetic - based position - sensing technology are described in U.S. Patent Nos. 5,539,199; 5,443,489; 5,558,091; 6,172,499; 6,239,724; 6,332,089; 6,484,118; 6,618,612; 6,690,963; 6,788,967; 6,892,091.
[0021] As seen in the inserted figure 25, the 2D ultrasonic array 65 generates a 3D fan - shaped ultrasonic beam 85 that occupies a defined solid angle, and such a beam is referred to herein as a "wedge 85". Using the wedge 85, the 2D ultrasonic array can image a substantial volume of an organ such as the entire intracardiac cavity (e.g., the entire left atrium 45). In the disclosed method, by electronically tilting the 3D beam or re - positioning the probe 60, a wedge 285 (or view 285) is generated that covers the anatomical regions of the heart 12 where pericardial effusion is likely to accumulate in the pericardial cavity 299.
[0022] System 10 includes one or more electrode patches 38 positioned to be in skin contact with patient 23 to establish a position reference for position pad 25 and impedance-based tracking of electrodes 26. For impedance-based tracking, a current is directed to electrodes 26 and detected at electrode patches 38, whereby the position of each electrode can be triangulated via electrode patches 38. Details of impedance-based location tracking techniques are described in U.S. Patent Nos. 7,536,218, 7,756,576, 7,848,787, 7,869,865, and 8,456,182.
[0023] Recorder 11 displays an electrogram 21 captured by body surface ECG electrodes 18 and an intracardiac electrogram (IEGM) captured by electrodes 26 of catheter 14. Recorder 11 may include pacing capabilities for pacing the rhythm of the heart and / or may be electrically connected to an independent pacer.
[0024] System 10 may include an ablation energy generator 50 adapted to conduct ablation energy to one or more electrodes at the distal tip of a catheter configured for ablation. The energy generated by ablation energy generator 50 may include radiofrequency (RF) energy, or pulsed-field ablation (PFA) energy including monopolar or bipolar high voltage DC pulses that can be used to effect irreversible electroporation (IRE), or combinations thereof, but is not limited thereto.
[0025] The patient interface unit (PIU) 30 is configured to establish electrical communication between the catheter, the electrophysiological equipment, the power supply, and the workstation 55 that controls the operation of the system 10. The electrophysiological equipment of the system 10 may include, for example, multiple catheters, a position pad 25, a body surface ECG electrode 18, an electrode patch 38, an ablation energy generator 50, and a recorder 11. Optionally, and preferably, the PIU 30 additionally includes processing capabilities for performing real-time calculations of catheter position and performing ECG calculations.
[0026] The workstation 55 includes memory 57, a processor unit 56 having memory or storage device in which appropriate operating software is loaded, and user interface functions. The workstation 55 may optionally provide several functions, including (i) modeling the endocardial anatomical structure in three dimensions (3D) and rendering the model or anatomical map 20 to be displayed on a display device 27, (ii) displaying an activation sequence (or other data) compiled from a recorded electrophoresis diagram 21 on the display device 27 as a representative visual representation or image superimposed on the rendered anatomical map 20, (iii) displaying the real-time position and orientation of multiple catheters in the cardiac chambers, and (iv) displaying target sites on the display device 27, such as the location where ablation energy is applied. One commercial product embodying the elements of system 10 is available as the CARTO® 3 system from Biosense Webster, Inc. (31A Technology Drive, Irvine, CA, 92618).
[0027] Figure 1 is provided as an example. ICE may be performed using a simpler fan-generated ultrasound catheter. The catheter 14 may include a position sensor embedded inside or near the multi-arm effector 40 to track the position of the distal end 40 of the shaft 22.
[0028] Intraoperative automated pericardial fluid monitoring using ICE Figures 2A–2C show schematic ultrasound images of pericardial effusion (PE) (169, 179, 189), mild (Figure 2A), moderate (Figure 2B), and severe (Figure 2C). The ultrasound images (169, 179, 189) are obtained by orientation of the tracked US probe 60 shown in Figure 1, as is the case in this disclosure.
[0029] Orientation information for the US probe 60 is calculated by the processor 56 from the signal acquired by the magnetic sensor 63, as shown in Figure 1. This information allows the processor 56 to select similar US ultrasound images (169, 179, 189) to assess the severity of PE during a clinical procedure.
[0030] In the example shown, the processor assesses PE severity by measuring the width of the pericardial fluid area (269, 279, 289) at 155. The processor alerts the physician if the measured width of 155 exceeds a predetermined threshold width.
[0031] The method shown in Figure 2 is provided as an example. In another example, the processor is configured to analyze subsequent ultrasound images (2B-2C) in comparison to a previous ultrasound image (2A) by estimating the area occupied by pericardial fluid in the ultrasound image and comparing it to a previously estimated area. The processor is configured to notify the user of PE detection if the area changes by an amount exceeding a given predetermined amount, or if the area exceeds a predetermined threshold area value.
[0032] In another example, the processor analyzes the volume of pericardial fluid (e.g., in the wedge of the image) in volumetric ultrasound acquisition mode to monitor the severity of PE.
[0033] Method for automated intraoperative pericardial fluid monitoring using ICE Figure 3 is a schematic flowchart illustrating a method for automatically monitoring pericardial effusion in real time by analyzing (169, 179, 189) US ultrasound images as shown in Figure 2, using an example from the present disclosure.
[0034] The algorithm in the example presented involves a process in which, in the US probe insertion step 302, the physician 24 inserts a US probe 60 for intracardiac ultrasound (ICE) equipped with a position sensor 63 into the inside of the cardiac chambers of the heart 12.
[0035] Next, in the mapping and / or ablation catheter insertion step 304, the physician inserts the distal end effector (e.g., effector 40) into the heart 12.
[0036] In tracking step 306, the processor 56 tracks the orientation of the US probe 60 using the sensor 63 on the US probe.
[0037] In parallel, during the US acquisition step 308, the processor 56 receives a wedge volume 285 acquired from the US probe 60, which contains at least a portion of the pericardial fluid.
[0038] In baseline recording step 310, the system records the baseline pericardial fluid state, which is typically expected to be similar to or less than that shown in Figure 2A.
[0039] In baseline recording step 312, the processor records the baseline pericardial fluid state during the initial cardiac ICE scan. This step may involve image analysis to determine an initial value of the pericardial fluid width 155.
[0040] In the orientation information saving step 311, the processor saves the ICE ultrasound image orientation of the baseline recording.
[0041] During the repeated acquisition step 314 of the clinical procedure, the system 10 automatically acquires additional ultrasound images of the pericardial cavity with the same ICE ultrasound image orientation as baseline (up to tolerance).
[0042] In the monitoring step 316, the processor 56 automatically monitors the pericardial cavity (fluid level) for changes in the image compared to the previous image (e.g., changes in pixel intensity), as shown in Figures 2A to 2C.
[0043] In threshold crossover verification step 318, the processor checks whether the threshold has been exceeded. If not, the process returns to step 314 to obtain new data.
[0044] If it is determined that the width 155 exceeds the threshold, the processor 56 notifies the user of the PE detection in notification step 320, for example by activating an audiovisual warning. The monitoring process continues by returning to step 314.
[0045] The flowchart shown in Figure 3 was selected simply to clarify the concept. This embodiment can be applied using any type of US probe, including a method for tracking its orientation, with necessary modifications. [Examples]
[0046] (Example 1) The medical system (10) includes an ultrasound probe (60) and a processor (56). The ultrasound probe is configured to be inserted into the heart (12) of the body and comprises (a) an ultrasound transducer array (65) configured to generate ultrasound images (169, 179, 189) of a portion of the heart, and (b) a sensor (63) configured to generate a signal indicating the orientation (285) of the ultrasound transducer array (65) within the heart. The processor is configured to (i) use signals generated by a sensor (63) to select two or more sequences (169, 179, 189) of ultrasound images acquired from a given orientation (285) of an ultrasound transducer array (65), wherein the ultrasound images (169, 179, 189) image at least a portion of the pericardial cavity (299) of the heart, (ii) estimate changes in pericardial effusion (PE) within the pericardial cavity (299) by analyzing the selected sequences (169, 179, 189) of ultrasound images, and (iii) initiate a response action when the changes meet specified conditions.
[0047] (Example 2) The system (10) according to Example 1, wherein the processor (56) is configured to record a baseline PE state (310) during an initial cardiac ultrasound probe (60) scan and to estimate changes in PE by comparing the PE level in subsequent images with the baseline.
[0048] (Example 3) The system (10) according to either of Examples 1 and 2, wherein the processor (56) is configured to estimate changes in PE by defining region boundaries and monitoring changes in PE (316), and by estimating visual changes in the region.
[0049] (Example 4) The system (10) according to either Example 1 or 2, wherein the processor (56) is configured to estimate the change in PE by estimating the width (155A, 155B, 155C) occupied by pericardial fluid and comparing it with a previously estimated width.
[0050] (Example 5) The system (10) according to any one of Examples 1, 2, and 4, wherein the processor (56) is further configured to notify the user of PE detection when the width (155A, 155B, 155C) exceeds a predetermined threshold width value.
[0051] (Example 6) The system (10) according to either of Examples 1 and 2, wherein the processor (56) is configured to estimate the change in PE by estimating the area occupied by pericardial fluid in ultrasound images (169, 179, 189) and comparing it with a previously estimated area.
[0052] (Example 7) The system (10) according to any one of Examples 1, 2, and 6, wherein the processor (56) is further configured to notify the user of PE detection when the area changes by an amount exceeding a predetermined threshold area value.
[0053] (Example 8) A system (10) according to any one of Examples 1 to 7, wherein the sensor (63) is configured to generate a signal in response to a magnetic field applied by a position tracking system.
[0054] (Example 9) A system (10) according to any of Examples 1 to 8, wherein a processor (56) is configured to select ultrasound images (169, 179, 189) by using an image processing algorithm.
[0055] (Example 10) A system (10) according to any of Examples 1 to 9, wherein the processor (56) is configured to initiate a response action by alerting the user of PE detection.
[0056] (Example 11) The method involves inserting an ultrasound probe (60) into the heart (12) of the body, the ultrasound probe comprising (a) an ultrasound transducer array (65) configured to generate ultrasound images (169, 179, 189) of a portion of the heart, and (b) a sensor (63) configured to generate a signal indicating the orientation (285) of the ultrasound transducer array (65) within the heart. Using the signal generated by the sensor, two or more sequences (169, 179, 189) of ultrasound images acquired from a given orientation (285) of the ultrasound transducer array (65) are selected, and the ultrasound images (169, 179, 189) image at least a portion of the pericardial cavity (299) of the heart. By analyzing the selected sequences (169, 179, 189) of ultrasound images, a change in pericardial effusion (PE) in the pericardial cavity (299) is estimated. When the change meets a defined condition, a response action is initiated.
[0057] While the embodiments described herein primarily address cardiac diagnostic applications, the methods and systems described herein may also be used for other medical applications.
[0058] The embodiments described above are illustrative examples, and it will be understood that this disclosure is not limited to those specifically illustrated and described above. Rather, the scope of this disclosure includes both combinations and partial combinations thereof of the various features described above, as well as variations and modifications thereof not disclosed in the prior art, which will be conceivable to those skilled in the art by reading the above description.
[0059] [Implementation Method] (1) A medical system, An ultrasound probe for insertion into the heart of the body, An ultrasonic transducer array configured to generate an ultrasonic image of a portion of the heart, An ultrasonic probe includes a sensor configured to generate a signal indicating the orientation of the ultrasonic transducer array within the heart, It is a processor, Using the signal generated by the sensor, select two or more sequences of ultrasound images acquired from a given orientation of the ultrasound transducer array, wherein the ultrasound images capture at least a portion of the pericardial cavity of the heart. By analyzing the selected sequence of ultrasound images, the change in pericardial effusion (PE) in the pericardial cavity is estimated, When the aforementioned change satisfies the specified conditions, a response action is initiated. A processor configured to perform the following actions: A medical system equipped with these features. (2) The system according to Embodiment 1, wherein the processor is configured to record a baseline PE state during an initial cardiac ultrasound probe scan and to estimate changes in PE by comparing the PE level in subsequent images with the baseline. (3) The system according to Embodiment 1, wherein the processor is configured to estimate changes in PE by defining region boundaries, monitoring changes in PE, and estimating visual changes in the region. (4) The system according to Embodiment 1, wherein the processor is configured to estimate the change in PE by estimating the width occupied by pericardial fluid and comparing it with a previously estimated width. (5) The system according to Embodiment 4, wherein the processor is further configured to notify the user of PE detection when the width exceeds a predetermined threshold width value.
[0060] (6) The system according to Embodiment 1, wherein the processor is configured to estimate the change in PE by estimating the area occupied by pericardial fluid in the ultrasound image and comparing it with a previously estimated area. (7) The system according to embodiment 6, wherein the processor is further configured to notify the user of PE detection when the area changes by an amount exceeding a predetermined threshold area value. (8) The system according to Embodiment 1, wherein the sensor is configured to generate the signal in response to a magnetic field applied by a position tracking system. (9) The system according to Embodiment 1, wherein the processor is configured to select the ultrasound image by using an image processing algorithm. (10) The system according to Embodiment 1, wherein the processor is configured to initiate a response action by warning the user of PE detection.
[0061] (11) A method, The procedure involves inserting an ultrasound probe into the heart of the body, wherein the ultrasound probe is An ultrasonic transducer array configured to generate an ultrasonic image of a portion of the heart, Insertion includes a sensor configured to generate a signal indicating the orientation of the ultrasonic transducer array within the heart, Using the signal generated by the sensor, select two or more sequences of ultrasound images acquired from a given orientation of the ultrasound transducer array, wherein the ultrasound images capture at least a portion of the pericardial cavity of the heart. By analyzing the selected sequence of ultrasound images, the change in pericardial effusion (PE) in the pericardial cavity is estimated, When the aforementioned change satisfies the specified conditions, a response action is initiated. Methods that include... (12) The method according to Embodiment 11, wherein estimating the change in PE includes recording a baseline PE state during an initial cardiac ultrasound probe scan and comparing the PE level in subsequent images with the baseline. (13) The method according to Embodiment 11, wherein estimating changes in PE includes defining area boundaries, monitoring changes in PE, and estimating visual changes in the area. (14) The method according to Embodiment 11, wherein estimating the change in PE includes estimating the width occupied by pericardial fluid and comparing it with a previously estimated width. (15) The method according to Embodiment 14, which includes notifying the user of PE detection when the width exceeds a predetermined threshold width value.
[0062] (16) The method according to Embodiment 11, wherein estimating the change in PE includes estimating the area occupied by pericardial fluid in the ultrasound image and comparing it with a previously estimated area. (17) The method according to embodiment 16, wherein the processor is further configured to notify the user of PE detection when the area changes by an amount exceeding a predetermined threshold area value. (18) The method according to embodiment 11, wherein the sensor is configured to generate the signal in response to a magnetic field applied by a position tracking system. (19) The method according to Embodiment 11, wherein selecting the ultrasound image includes using an image processing algorithm. (20) The method according to Embodiment 11, wherein initiating a response action includes alerting the user to PE detection.
Claims
1. It is a medical system, An ultrasound probe for insertion into the heart of the body, An ultrasonic transducer array configured to generate an ultrasonic image of a portion of the heart, An ultrasonic probe includes a sensor configured to generate a signal indicating the orientation of the ultrasonic transducer array within the heart, It is a processor, Using the signal generated by the sensor, select two or more sequences of ultrasound images acquired from a given orientation of the ultrasound transducer array, wherein the ultrasound images capture at least a portion of the pericardial cavity of the heart. By analyzing the selected sequence of ultrasound images, the change in pericardial effusion (PE) in the pericardial cavity is estimated, When the aforementioned change satisfies the specified conditions, a response action is initiated. A processor configured to perform the following actions: A medical system equipped with these features.
2. The system according to claim 1, wherein the processor is configured to record a baseline PE state during an initial cardiac ultrasound probe scan and to estimate changes in PE by comparing the PE level in subsequent images with the baseline.
3. The system according to any one of claims 1 to 2, wherein the processor is configured to estimate changes in PE by defining region boundaries, monitoring changes in PE, and estimating visual changes in the region.
4. The system according to any one of claims 1 to 2, wherein the processor is configured to estimate a change in PE by estimating the width occupied by pericardial fluid and comparing it with a previously estimated width.
5. The system according to claim 4, wherein the processor is further configured to notify the user of PE detection when the width exceeds a predetermined threshold width value.
6. The system according to any one of claims 1 to 2, wherein the processor is configured to estimate the area occupied by pericardial fluid in the ultrasound image and to estimate the change in PE by comparing it with a previously estimated area.
7. The system according to claim 6, wherein the processor is further configured to notify the user of PE detection when the area changes by an amount exceeding a predetermined threshold area value.
8. The system according to any one of claims 1 to 2, wherein the sensor is configured to generate the signal in response to a magnetic field applied by a position tracking system.
9. The system according to any one of claims 1 to 2, wherein the processor is configured to select the ultrasound image by using an image processing algorithm.
10. The system according to any one of claims 1 to 2, wherein the processor is configured to initiate a response action by warning the user of PE detection.
11. It is a method, The procedure involves inserting an ultrasound probe into the heart of the body, wherein the ultrasound probe is An ultrasonic transducer array configured to generate an ultrasonic image of a portion of the heart, Insertion includes a sensor configured to generate a signal indicating the orientation of the ultrasonic transducer array within the heart, Using the signal generated by the sensor, select two or more sequences of ultrasound images acquired from a given orientation of the ultrasound transducer array, wherein the ultrasound images capture at least a portion of the pericardial cavity of the heart. By analyzing the selected sequence of ultrasound images, the change in pericardial effusion (PE) in the pericardial cavity is estimated, When the aforementioned change satisfies the specified conditions, a response action is initiated. Methods that include...