System and method for planning radiation dose for cardiac radiation therapy

Abstract

System and method (400) for simulating the radiation effect of cardiac ablation includes a processor generating a cardiac simulation model configured to simulate the electrical activity of a patient's heart (402). The processor determines a simulated post-radiation state of the patient's heart by adjusting the cardiac simulation model to account for the effect of a radiation therapy plan on the simulated electrical activity of the patient's heart (404). The processor uses the adjusted cardiac simulation model to simulate the simulated post-radiation state of the heart with a stimulus that induces an arrhythmia (406), determines whether an arrhythmia is induced based on the electrical activity generated when simulating the simulated post-radiation state of the heart with the stimulus (408), and outputs an indicator of whether an arrhythmia is induced (410). The processor proposes a modification to the radiation plan if an arrhythmia is induced.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims priority to U.S. patent application Ser. No. 17 / 855,257, filed June 30, 2022, the entire contents of which are incorporated herein by reference.

[0002] This application relates generally to systems and methods for planning cardiac radiation therapy, and more particularly to systems and methods for simulating the effects of radiation on electrical or electrophysiological properties of the heart and optimizing or adjusting radiation dose distribution based on the results of the simulation to reduce or eliminate the recurrence of one or more cardiac pathological conditions, including simulating one or more pathological conditions and checking for potential recurrence. [Background technology]

[0003] Cardiac ablation is an invasive medical procedure typically used to treat various cardiac conditions, such as atrial fibrillation (AFib), atrial flutter, atrial tachycardia, ventricular tachycardia (VT), atrioventricular nodal reentrant tachycardia (AVNRT), paroxysmal supraventricular tachycardia (PSVT), Wolff-Parkinson-White syndrome, or cardiac tumors. A standard radiological cardiac procedure involves a physician inserting a catheter into a patient's body to access the heart. Heat or extreme cold is then applied to destroy abnormal areas of the heart and disrupt abnormal electrical signals through the heart. This procedure carries risks for at least some patients and typically requires subsequent monitoring in an intensive care unit. Some of the risks associated with standard radiological ablation include bleeding or infection at the catheter insertion site, blood vessel damage, heart valve damage, new or worsening arrhythmias, bradycardia, blood clots, stroke or heart attack, pulmonary vein stenosis, kidney damage from the contrast agent used in the procedure, and / or death in rare cases.

[0004] Cardiac radiotherapy ablation (also called cardiac radioablation) is a non-invasive form of cardiac ablation. Instead of catheters, a radiation dose is used to target and destroy or correct abnormal areas of the heart. The use of radiation mitigates some of the risks associated with invasive procedures and offers relief to high-risk cardiac patients who may have largely exhausted other options. However, cardiac radioablation carries its own risks and presents its own challenges. Among these is the risk of destroying surrounding healthy tissue, particularly in the cardiac region. This risk requires precise delivery in terms of radiation area and radiation dose.

[0005] Prior to a radiation therapy ablation procedure, a radiation therapy treatment plan is developed, the goal of which is to optimize the radiation angles and / or the radiation dose at each angle to ensure that the target area receives a high radiation dose and the intervening tissue receives a low radiation dose. Summary of the Invention

[0006] According to a first aspect of the present invention, there is provided a method for simulating a radiation effect of cardiac ablation according to claim 1. According to a second aspect of the present invention, there is provided a system for simulating the radiation effect of cardiac ablation according to claim 11. Optional features are defined in the dependent claims.

[0007] Aspects described herein relate to optimizing or improving radiation dose distribution for radiation cardiac ablation to reduce or eliminate the recurrence of cardiac rhythm disturbances (heart rhythm disturbances) associated with cardiac pathological conditions. A computer system can generate a patient-specific cardiac simulation model that can mimic or reproduce the electrical activity of a patient's heart. In the cardiac simulation model, electrical activity or activation signals can be modeled using a set of parameters. The computer system can determine the effect of the radiation distribution (or radiation treatment plan) on the set of parameters that model the electrical activity or signals generated by the cardiac simulation model and adjust the set of parameters accordingly. The adjusted cardiac simulation model represents or corresponds to a post-irradiation state of the heart in terms of reproducing the electrical activity of the patient's heart. The computer system can virtually stimulate a cardiac rhythm disturbance associated with a cardiac pathological condition in the adjusted cardiac simulation model and check whether the stimulation causes the recurrence of the cardiac rhythm disturbance. If a recurrence of the cardiac rhythm disturbance is detected, the computer system can adjust the radiation distribution (or radiation treatment plan), for example, by changing the radiation dose value and / or changing the target region. The computer system can iteratively adjust the radiation distribution and / or parameters of the cardiac simulation model and / or check for recurrence of the cardiac rhythm disorder until a recurrence of the cardiac rhythm disorder is achieved or not detected, and if a recurrence of the pathological condition is not achieved or not detected, the corresponding radiation distribution can be used to proceed with the radiation treatment plan.

[0008] According to one aspect, a method for simulating a radiation effect of cardiac ablation may include one or more processors generating a cardiac simulation model of a patient's heart based on medical images and / or electrophysiological data of the patient. The cardiac simulation model may be configured to simulate electrical activity of the patient's heart. The method may include one or more processors determining a simulated post-radiation state of the patient's heart by adjusting the cardiac simulation model to account for the effect of a radiation treatment plan on the simulated electrical activity of the patient's heart. The radiation treatment plan specifies radiation doses to be applied to different regions of the patient's heart. The method may include one or more processors using the adjusted cardiac simulation model to simulate a simulated post-radiation state of the heart with stimulation to induce a cardiac rhythm disorder, determining whether a cardiac rhythm disorder is induced based on electrical activity generated when simulating the simulated post-radiation state of the heart with stimulation, and / or outputting an indication of whether a cardiac rhythm disorder is induced in the simulated post-radiation state of the heart.

[0009] In some embodiments, the cardiac rhythm disorder is associated with at least one of ventricular tachycardia (VT), atrial tachycardia, ventricular fibrillation, or atrial fibrillation. In some embodiments, the electrical activity is defined in a cardiac simulation model using multiple parameters of multiple electrical activity signals. Each electrical activity signal is associated with a corresponding region of the patient's heart. Adjusting the cardiac simulation model can include adjusting parameters of the electrical activity signal associated with a region of the patient's heart scheduled to receive radiation during the radiation treatment plan. Each electrical activity signal can have multiple phases, and each phase can be defined by one or more corresponding parameters. Adjusting the parameters of the electrical activity signals can include determining a change in the parameters of each phase of the electrical activity signal due to the effect of a corresponding radiation dose on the region of the patient's heart scheduled to receive radiation, and modifying the parameters of each phase of the electrical activity signal according to the determined change.

[0010] In some embodiments, the electrical activity is defined in the cardiac simulation model using one or more parameters of conduction velocity. Adjusting the cardiac simulation model can include adjusting at least one parameter of the one or more parameters of conduction velocity. In some embodiments, determining a simulated post-irradiation state of the heart can include identifying tissue of the patient's heart that is expected to be electrically inactive in response to the radiation treatment plan.

[0011] In some embodiments, simulating a simulated post-radiation state of the heart using stimulation to induce a cardiac rhythm disorder can include simulating a virtual catheter-based stimulation in the post-radiation state of the heart.

[0012] In some embodiments, the method can further include, upon determining that a cardiac rhythm disturbance is induced, suggesting one or more modifications to the radiation treatment plan, wherein the one or more modifications to the radiation treatment plan can include at least one of modifying a radiation dose to a first region of the heart specified in the radiation treatment plan or modifying a second region of the heart scheduled to receive radiation during the radiation treatment plan.

[0013] According to another aspect, a system for simulating a radiation effect of cardiac ablation may include one or more processors and a memory storing computer code instructions. The computer code instructions, when executed, cause the one or more processors to generate a cardiac simulation model of the patient's heart based on medical images and / or electrophysiological data of the patient. The cardiac simulation model may be configured to simulate electrical activity of the patient's heart. The one or more processors may determine a simulated post-radiation state of the heart by adjusting the cardiac simulation model to account for the effect of a radiation treatment plan on the simulated electrical activity of the patient's heart. The radiation treatment plan may specify radiation doses to be applied to different regions of the patient's heart. The one or more processors may use the adjusted cardiac simulation model to simulate a simulated post-radiation state of the heart with a stimulus that induces a cardiac rhythm disorder, determine whether a cardiac rhythm disorder is induced in the simulated post-radiation state of the patient's heart, and / or output an indication of whether a cardiac rhythm disorder is induced in the simulated post-radiation state of the patient's heart.

[0014] In some embodiments, the cardiac rhythm disorder may be associated with at least one of ventricular tachycardia (VT), atrial tachycardia, ventricular fibrillation, or atrial fibrillation. In some embodiments, the electrical activity may be defined in the cardiac simulation model using multiple parameters of multiple electrical activity signals. Each electrical activity signal may be associated with a corresponding region of the patient's heart. When adjusting the cardiac simulation model, the one or more processors may adjust parameters of the electrical activity signals associated with regions of the patient's heart scheduled to receive radiation during radiation therapy planning. Each electrical activity signal may have multiple phases, and each phase may be defined by one or more corresponding parameters. When adjusting the parameters of the electrical activity signals, the one or more processors may determine a change in the parameters of each phase of the electrical activity signals due to an effect of a corresponding radiation dose in the region of the patient's heart scheduled to receive radiation and modify the parameters of each phase of the electrical activity signals according to the determined change.

[0015] In some embodiments, the electrical activity can be defined in the cardiac simulation model using one or more parameters of conduction velocity. When adjusting the cardiac simulation model, the one or more processors can adjust at least one parameter of the one or more parameters of conduction velocity. In some embodiments, when determining the simulated post-irradiation state of the heart, the one or more processors can identify tissue in the patient's heart that is expected to be electrically inactive in response to the radiation treatment plan.

[0016] In some embodiments, when simulating a post-radiation state of the heart using stimulation to induce a cardiac rhythm disorder, one or more processors can simulate virtual catheter-based stimulation in the post-radiation state of the heart.

[0017] In some embodiments, the one or more processors can further suggest one or more modifications to the radiation treatment plan upon determining that a cardiac rhythm disturbance is induced, wherein the one or more modifications to the radiation treatment plan can include at least one of modifying a radiation dose to a first region of the heart specified in the radiation treatment plan or modifying a second region of the heart scheduled to receive radiation during the radiation treatment plan.

[0018] According to yet another aspect, a computer-readable medium may include stored computer code instructions. When executed, the computer code instructions may cause one or more processors to generate a cardiac simulation model of the patient's heart based on medical images and / or electrophysiological data of the patient. The cardiac simulation model may be configured to simulate electrical activity of the patient's heart. The one or more processors may determine a simulated post-irradiation state of the heart by adjusting the cardiac simulation model to account for the effect of a radiation treatment plan on the simulated electrical activity of the patient's heart. The radiation treatment plan may specify radiation doses to be applied to different regions of the patient's heart. The one or more processors may use the adjusted cardiac simulation model to simulate a simulated post-irradiation state of the heart involving a stimulus that induces a cardiac rhythm disorder, determine whether a cardiac rhythm disorder is induced in the simulated post-irradiation state of the patient's heart, and / or output an indication of whether a cardiac rhythm disorder is induced in the simulated post-irradiation state of the patient's heart. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 shows a block diagram illustrating a computing environment for implementing the methods and processes described herein, according to one embodiment. [Figure 2] FIG. 1 is a block diagram illustrating an example of a system architecture, according to one embodiment. [Figure 3]FIG. 1 is a block diagram of a system for simulating the effects of radiation on electrical properties of the heart, according to one embodiment. [Figure 4] 1 is a flow chart illustrating a method for simulating the effect of radiation on electrical or electrophysiological properties of the heart, according to one embodiment.

[0020] Some or all of the figures are schematic representations for explanatory purposes. The foregoing information and the following detailed description, including examples illustrating various aspects and embodiments, provide an overview or framework for understanding the nature and characteristics of the claimed aspects and embodiments. The figures provide illustrations and a further understanding of the various aspects and embodiments, and are incorporated in and constitute a part of this specification. DETAILED DESCRIPTION OF THE INVENTION

[0021] Various concepts and embodiments relating to methods, devices, and systems for predicting the location of cardiac regions in planning cardiac radiotherapy ablation are described in more detail below. The various concepts described above and in more detail below may be implemented in any of a number of ways, and the described concepts are not limited to any particular manner of implementation. Specific embodiments and applications are provided primarily for illustrative purposes.

[0022] Cardiac radiotherapy ablation holds the promise of being a safer and more effective ablation strategy compared to catheter-based ablation, primarily due to its non-invasive nature and potential ability to target all layers of the myocardium. However, to realize this potential, various challenges must be overcome. These challenges primarily stem from stringent requirements for radiometric accuracy. The heart consists of multiple structures at risk, including coronary arteries and valves. These structures should be spared from radiation (or receive relatively low radiation) to avoid permanent and significant damage to the heart. Meanwhile, treatment aims to apply a sufficiently high radiation dose to abnormal cardiac regions to destroy or at least alter their characteristics (e.g., electrophysiological properties). This tradeoff makes radiotherapy generally, and especially in the cardiac setting, a laborious and complex task.

[0023] One of the technical challenges associated with cardiac radiation therapy is planning and assessing the effectiveness of a radiation plan or corresponding radiation dose distribution. In other words, given a radiation dose distribution, how can we assess its effect on a patient's heart and determine whether it is sufficient to heal the patient's heart? To assess the effectiveness of radiation, physicians typically attempt to induce VT in the patient's heart using catheter stimulation after radiation treatment has been administered. However, such an approach is invasive and cannot be used for radiation dose planning because stimulation is performed after radiation treatment.

[0024] In the present disclosure, systems and methods are described for simulating the effects of radiation on a patient's heart. A cardiac simulation model configured to replicate the electrical activity of the heart is used. The effects of radiation are modeled as variations or adjustments of parameters of the cardiac simulation model. Digital catheter stimulation can be applied to the adjusted cardiac simulation model to determine whether a cardiac rhythm disorder can be induced. If the induction of a cardiac rhythm disorder is successful, the radiation dose distribution can be adjusted for better efficacy.

[0025] FIG. 1 , according to an embodiment, illustrates an example computing environment 100 for planning cardiac radiation therapy. Broadly, computing environment 100 may include a cardiac radiation therapy planning system 102, a radiation effects simulation system 104, a database 106, and / or a communication network 108. Cardiac radiation therapy planning system 102 may include an imaging device 110, an electrophysiology system 114, and / or one or more computing devices 112. Radiation effects simulation system 104 may include one or more computing devices, such as computing device 116a and computing device 116b, which are also referred to herein, individually or collectively, as computing devices 116. Computing device 116 is configured to simulate the effects of radiation on the heart or cardiac electrical activity. Cardiac radiation therapy planning system 102, radiation effects simulation system 104, and database 106 are communicatively coupled to each other via communication network 108.

[0026] The communication network 108 may include a local area network (LAN), a wireless local area network (WLAN), a metropolitan area network (MAN), a wide area network (WAN), the Internet, a cellular network, other types of networks, or combinations thereof. The network 108 may include both wired and wireless communications conforming to one or more standards and / or utilizing one or more transmission media. Communications over the network 108 may be performed according to various communication protocols, such as TCP / IP (Transmission Control Protocol and Internet Protocol), UDP (User Datagram Protocol), IEEE communication protocols, etc.

[0027] The cardiac radiation therapy planning system 102 may include one or more imaging devices 110, an electrophysiology system 114, and one or more computing devices 112. The imaging device 110 may include, among other things, a computed tomography (CT) scanner, a magnetic resonance (MR) scanner, a positron emission tomography (PET) scanner, or a combination thereof. The imaging device 110 may acquire medical images of a patient's heart through at least a portion of a cardiac cycle. In some embodiments, the imaging device 110 may acquire a series of images representing the motion or deformation of the heart through the cardiac cycle or a portion thereof. The acquired medical images may include CT images, computed tomography angiography (CTA) images, MR images, PET images, other types of medical images, or a combination thereof.

[0028] The electrophysiology system 114 is configured to perform electrophysiological tests on a patient, for example, to evaluate the heart's electrical system and diagnose abnormal heart rhythms or arrhythmias. The electrophysiology system 114 may include one or more catheters, multiple wire electrodes, and a computing device connected to the wire electrodes to record electrical signals. A physician inserts a catheter into a vein in the patient's groin and then inserts wire electrodes into the patient's heart via the catheter and vein. In some embodiments, the electrophysiology system 114 may include multiple electrocardiogram (ECG) electrodes placed on the patient's body (e.g., chest) using a multi-electrode vest. The heart's natural electrical pulses are conducted through the wire electrodes and recorded by the computing device of the electrophysiology system 114. The computing device of the electrophysiology system 114 may send electrical signals through the electrodes to attempt to stimulate cardiac tissue and induce abnormal heart rhythms.

[0029] The computing device 112 can receive medical images from the imaging device 110 and electrophysiology test data from the electrophysiology system 114. The computing device 112 can also acquire other patient medical data, such as ECG data, blood pressure data, and / or other patient data. The computing device 112 can be configured to run or perform radiation simulations as part of radiation treatment planning. A radiation treatment planner can use the computing device 112 to simulate one or more radiation treatment parameter sets and determine which parameter set results in a desired radiation dose distribution. The computing device 112 can also send acquired patient data, such as medical images and electrophysiology test data, to the database 106.

[0030] The radiation effects simulation system 104 (or each computing device 116) may be configured to generate a cardiac simulation model configured to mimic the patient's heart in terms of electrical activity using acquired medical images and / or electrophysiological test data of the patient. The effects of radiation on the patient's heart may be simulated as adjustments to parameters of the cardiac simulation model. The adjusted cardiac simulation model may be simulated using digital catheter stimulation to induce a cardiac rhythm disorder. If the induction of the cardiac rhythm disorder is successful, the radiation dose distribution may not be efficient in healing the heart. Testing for potential recurrence of the cardiac rhythm disorder is a predictor of spontaneous recurrence of the cardiac rhythm disorder in the patient's heart after radiation treatment. Simulation of the effects of radiation and digital stimulation may help improve radiation treatment planning and its effectiveness. Functional characteristics of the radiation effects simulation system 104 (or each computing device 116) are described in more detail below in conjunction with FIGS. 3-4.

[0031] In some embodiments, one or more computing devices 116 are configured to execute computer instructions to perform any of the methods or operations of the methods described herein. One or more computing devices 116 can generate and display an electronic platform for displaying information indicative of or related to the effect of radiation on the heart. The electronic platform can include a graphical user interface (GUI) that receives input data and / or displays an indication of whether the induction of the cardiac rhythm disturbance was successful. An example of an electronic platform generated and managed by one or more computing devices 106 can be a web-based application or website configured to be displayed on various electronic devices, such as mobile devices, tablets, personal computers, etc.

[0032] It should be noted that while FIG. 1 illustrates a network-based implementation, the methods described herein may also be implemented by a single computing device that receives a patient's medical images and / or electrophysiological data and predicts the effects of radiation on the patient's heart in accordance with the methods described herein. The computing environment 100 is not necessarily limited to the components described herein and may include additional or alternative components not shown for the sake of brevity, and such components should still be considered within the scope of the embodiments described herein. By way of example, the computing environment 100 may include additional or alternative databases, such as within the cardiac radiation treatment planning system 102 or the radiation effects simulation system 104. Additionally, the number of computing devices included in the cardiac radiation treatment planning system 102 or the radiation effects simulation system 104 may vary according to various implementations.

[0033] Referring to FIG. 2 according to an embodiment, a block diagram illustrating one embodiment of a system architecture of a computing system 200 that may be used to perform the methods described herein is shown. The computing system 200 may include a computing device 202. The computing device 202 may exemplify any of the embodiments of device 112 and / or device 116 of FIG. 1. The computing device 202 may include, by way of example and not limitation, a computed tomography (CT) scanner, a medical linear accelerator, a desktop, a laptop, a hardware computer server, a workstation, a personal digital assistant (PDA), a mobile computing device, a smartphone, a tablet, or any other type of computing device. The computing device 202 may include one or more processors 204 that execute computer code instructions, a memory 206, and a bus 208 that communicatively couples the processor 204 and the memory 206.

[0034] The one or more processors 204 may include a microprocessor, a general-purpose processor, a multi-core processor, a digital signal processor (DSP) or field programmable gate array (FPGA), an application-specific integrated circuit (ASIC), or other type of processor. The one or more processors 204 may be communicatively coupled to a bus 208 for processing information. The memory 206 may include a main memory device 210, such as a random access memory (RAM) or other dynamic storage device, coupled to the bus 208 for storing information and instructions to be executed by the processor 204. The main memory device 210 may be used to store temporary variables or other intermediate information during execution of instructions by the processor 204 (e.g., in connection with the methods described herein, such as method 400). The computing device 202 may include a read-only memory (ROM) 212 or other static storage device coupled to the bus 208 for storing static information and instructions for the processor 204. For example, the ROM 212 may store medical images of a patient, for example, received as input. The ROM 212 may store computer code instructions relating to or representing the execution of the methods described herein. A storage device 214, such as a solid-state device, magnetic disk, or optical disk, may be coupled to the bus 208 for storing (or providing as input to) information and / or instructions.

[0035] The computing device 202 may be communicatively connected to or include an input device 216 and / or an output device 218. The computing device 202 may be connectable to the output device 218 via a bus 208. The output device 218 may include a display device, such as a liquid crystal display (LCD), a thin film transistor LCD (TFT), an organic light emitting diode (OLED) display, an LED display, an electronic paper display, a plasma display panel (PDP), or other display, for displaying information to a user. The output device 218 may include a communication interface for communicating information to other external devices. An input device 216, such as a keyboard with alphanumeric and other keys, may be connected to the bus 208 for communicating information and command selections with the processor 204. In another embodiment, the input device 216 may be incorporated into a display device, such as a touchscreen display. The input device 216 may include a cursor control, such as a mouse, a trackball, or cursor direction keys, for communicating directional information and command selections to the processor 204 and for controlling cursor movement on a display device.

[0036] According to various embodiments, the methods or operations (steps) described herein may be implemented as sequences of computer code instructions executed by the processor 204 of the computing system 200. The sequences of computer code instructions may be loaded into the main memory device 210 from another computer-readable medium, such as the ROM 212 or the storage device 214. Execution of the sequences of computer code instructions stored in the main memory device 210 causes the computing system 200 to perform the methods or operations of the methods described herein. In some embodiments, one or more processors 204 in a multi-processor configuration may be used to execute computer code instructions that embody embodiments of the methods or processes described herein. In some other embodiments, hardwired circuitry may be used in place of or in combination with software instructions to implement embodiments of the methods or operations thereof described herein. In general, embodiments are not limited to any specific combination of hardware circuitry and software. The functional acts described herein may be performed by other types of digital electronic circuitry, computer software, firmware, hardware, or combinations thereof.

[0037] Referring to Figure 3, in accordance with an embodiment, a block diagram of the radiation effects simulation system 104 shown in Figure 1 is shown. The radiation effects simulation system 104 is a system for simulating the effects of radiation on a patient's heart, including effects on the electrophysiological properties or electrical activity of the heart and / or pathological effects related to the potential recurrence of rhythm disturbances associated with pathological conditions. In general, the radiation effects simulation system 104 can include a simulation model generator 302 that generates a cardiac simulation model, a radiation effect estimator 304, a rhythm disturbance simulator 306, a rhythm disturbance detector 308, and a radiation treatment plan update component 310.

[0038] The radiation effects simulation system 104 may include or be connected to a database 106. The database 106 may include image data 312, electrophysiological data 314, and / or other patient data 316. The image data 312 may include CT images, CTA images, and / or other medical images of the patient. The electrophysiological data 314 may include electrophysiological test data of the patient, which indicates the electrical activity of the patient's heart through at least a cardiac cycle or a portion thereof. For example, the electrophysiological data 314 may include one or more electrical signals generated by the patient's heart and recorded by the electrophysiology system 114 via one or more electrodes. The electrophysiology system 114 may record electrical signals following invasive or non-invasive procedures. The other patient data 316 may include blood pressure data, ECG data, medical history data, demographic data, or a combination thereof.

[0039] Each of components 302, 304, 306, 308, and / or 310 may be implemented as a software component, a hardware component, a firmware component, or a combination of software, firmware, and / or hardware. For example, any of these components may be implemented as computer code instructions executed by one or more processors, such as processor 204, to perform their respective functional steps or processes. Any of components 302, 304, 306, 308, and / or 310 may be implemented as digital circuitry. The functional steps or processes associated with each of these components are described in more detail below in conjunction with FIG. 4.

[0040] 4, according to an embodiment, shows a flowchart illustrating one embodiment of a method 400 for simulating the effect of radiation on electrical or electrophysiological properties of the heart for cardiac radiation therapy planning. Generally, the method 400 can include generating a cardiac simulation model of the heart (step 402). For example, one or more processors can generate the cardiac simulation model of the patient's heart based on medical images and / or electrophysiological data of the patient, where the cardiac simulation model is configured to simulate the electrical activity of the patient's heart.

[0041] Method 400 may also include determining a simulated post-irradiation state of the heart by adjusting the cardiac simulation model to account for the effect of the radiation treatment plan on the simulated electrical activity of the heart (step 404). For example, the one or more processors may determine a simulated post-irradiation state of the patient's heart by adjusting the cardiac simulation model to account for the effect of the radiation treatment plan on the simulated electrical activity of the patient's heart, the radiation treatment plan specifying radiation doses to be applied to different regions of the patient's heart.

[0042] The method 400 can include simulating a post-radiation state of the heart with stimulation to induce a cardiac rhythm disorder (step 406). For example, the one or more processors can use the adjusted cardiac simulation model to simulate a post-radiation state of the heart with stimulation to induce a cardiac rhythm disorder.

[0043] Method 400 may include determining whether a cardiac rhythm disorder is induced (step 408). For example, the one or more processors may determine whether a cardiac rhythm disorder is induced based on electrical activity generated when simulating a post-radiation state of the heart with stimulation.

[0044] The method 400 can include outputting an indication of whether a cardiac rhythm disturbance is induced in the simulated post-irradiation state of the heart (step 410). For example, the one or more processors can output an indication of whether a cardiac rhythm disturbance is induced in the simulated post-irradiation state of the heart.

[0045] The method 400 may be performed by the computing device 116 or a processor thereof, such as the processor 204 .

[0046] 1-4 , the method 400 may include one or more processors 204 or simulation model generator 302 generating 402 a cardiac simulation model of the patient's heart using patient image data 312 and electrophysiological data 314. Prior to a cardiac ablation procedure, the imaging device 110 may acquire the patient image data 312. The image data 312 may include cardiac-gated CTA images, CT images, MR images, other types of medical images, or a combination thereof. Additionally, the electrophysiology system 114 may record the patient's electrophysiological test data 314 representing the electrical activity of the patient's heart. The computing device 112 may store the image data 312 and the electrophysiological data 314 in the database 106.

[0047] A physician or other medical professional may mark or outline a ROI to receive radiation in one or more of the acquired medical images of the patient, e.g., based on the image data 312 and the electrophysiological data 314. For example, the physician may manually identify or mark (e.g., on a display of the computing device 112) the boundaries of the ROI to receive radiation. In some embodiments, the computing device 112 may process the marked image to refine the boundaries of the ROI, e.g., using an image segmentation algorithm, an object identification algorithm, other image processing algorithms, or a combination thereof. The computing device 112 may use the refined (or original marked) ROI boundaries to identify the same ROI in other unmarked images of the patient. In some embodiments, the physician may mark the ROI in all of the acquired medical images.

[0048] In some embodiments, the ROI may include or be one or more segments of a standardized N-segment model (where N is an integer). For example, the standardized N-segment model may include a standardized AHA17-segment cardiac model. The standardized N-segment model represents a standard geometric description or segmentation of the heart. The computing device 112 may identify the segments based on a parametric model of the cardiac chambers (ventricles and atria), such as that described in “Four-Chamber Heart Modeling and Automatic Segmentation for 3-D Cardiac CT Volumes Using Marginal Space Learning and Steerable Features,” IEEE Transactions on Medical Imaging 27, no. 11 (November 2008) 1668-81, which is incorporated herein by reference. In some embodiments, other standardized geometric models of the heart may be used. An operator of the computing device 112 may identify the ROI as one or more segments of the standardized N-segment model, for example, using a user interface displayed by the computing device 112.

[0049] The medical images acquired by the imaging device 110 may be two-dimensional images. The processor 204 or simulation model generator 302 may use the medical image data 312 to generate a patient-specific geometric model of the patient's heart. The patient-specific geometric model may include a three-dimensional (3D) model representing anatomical features, such as the shape, size, and / or various anatomical regions, of the patient's heart. For example, the processor 204 or simulation model generator 302 may use the patient's medical images to generate a 3D mesh of the patient's heart. The processor 204 or simulation model generator 302 may add one or more layers on top of the 3D mesh to reflect separate regions or segments of the patient's heart.

[0050] In some embodiments, the processor 204 or the simulation model generator 302 can register the electrophysiological data to the generated 3D model of the patient's heart. In some embodiments, the processor 204 or the simulation model generator 302 can combine the electrophysiological data with one or more generated 3D models of the patient's heart, as described in U.S. Patent No. 9,463,072, the contents of which are incorporated herein by reference. The electrical activity of a patient's heart varies spatially across the surface of the heart through the myocardium. In general, the heart includes cardiac contractile cells and cardiac conduction cells. The cardiac conduction cells represent approximately 1 percent of the cells in the atria and ventricles and form the cardiac conduction system, including the sinoatrial (SA) node and the atrioventricular (AV) node. The cardiac conduction cells generate and propagate electrical impulses throughout the heart. The cardiac contractile cells represent approximately 99% of the cells in the atria and ventricles. They also conduct electrical impulses and are primarily responsible for the contractions that respond to the electrical impulses and pump blood throughout the body. Thus, the heart acts as an electromechanical system in which electrical impulses are generated by the cardiac conduction system and propagated within the myocardial contractile cells to induce contraction.

[0051] The processor 204 or the simulation model generator 302 can generate a simulated electrical model configured or structured to mimic or replicate the electrical activity of the patient's heart. The simulated electrical model can be configured to generate signals similar to those of the electrophysiological data 314. The simulated electrical model can be a network of connected nodes, with each node representing a block or portion of the myocardium (or heart). Each node in the simulated electrical model can be associated with a respective activation signal and a respective conduction velocity. Each activation signal can be a function that peaks or rises relatively quickly and then slowly decays to zero over time. Each activation signal at a corresponding node can be defined by a respective set of parameters.

[0052] In some embodiments, each electrically active signal can have multiple phases, and each phase can be defined by one or more corresponding parameters. In other words, each phase of the active signal can be described in terms of a parameterized mathematical formulation. For example, a first phase of the active signal can have a steep slope, described or defined by a first parameterized mathematical formulation having one or more first parameters. A second phase of the active signal can exhibit a slow decay and can be described or defined by a second parameterized mathematical formulation having one or more second parameters.

[0053] The parameters of each activation signal or its phase may be related to the underlying biology of the corresponding block or portion of the myocardium. For example, the activation signal parameters may be set based on experimental data. Similarly, the conduction velocity parameters corresponding to various nodes or portions of the myocardium may be set based on experimental data. Results of experiments performed on animal hearts and / or human hearts may be used to set the parameters of the simulated electrical model, including the activation signal parameters and / or the conduction velocity parameters.

[0054] Conduction velocities associated with various nodes correlate with or depend on the activation signal of the node or corresponding heart block or segment. Under healthy conditions, the steepness of the activation signal's ramp is the primary determinant of conduction velocity. The steeper the ramp, the higher the conduction velocity. In other words, how quickly an electrical signal propagates through the myocardium or network of nodes depends on how steep the activation signal's ramp is. For example, if the activation signal associated with a corresponding node reaches its peak within 100 microseconds and the activation threshold of an adjacent node is approximately half the peak amplitude, the adjacent node should be activated in approximately 50 microseconds. On the other hand, if the activation signal reaches its peak in 500 microseconds, the adjacent node should be activated within approximately 250 microseconds. In the heart, a first cell is activated or triggered (e.g., exhibits a respective activation signal) by the activation signal of an adjacent cell. Thus, the steeper the ramp of the adjacent cell's activation signal, the faster the first cell is activated, which is how the properties of one cell affect conduction velocity.

[0055] Additionally, the decay phase of the active signal depends on the ramp or peak of the active signal. The decay phase can follow a predetermined pattern described by a parameterized mathematical formulation, where the first value of the decay phase depends on the peak of the active signal. The higher the peak, the higher the first value of the decay phase of the active signal. Thus, the parameters of the mathematical formulation of the decay phase change as the peak of the active signal changes.

[0056] The processor 204 or the simulation model generator 302 can model the conduction velocity and activity signal based on experimental data for healthy and abnormal tissue. In particular, the parameterization functions can be predefined based on experimental data for healthy and abnormal tissue. The processor 204 or the simulation model generator 302 can also set the conduction velocity parameters and the parameterization functions or parameter values ​​for each phase using, for example, a lookup table or other data structure that holds parameter values ​​for various tissue conditions (e.g., healthy tissue, tissue exhibiting VT, tissue exhibiting AFib, tissue exhibiting atrial flutter, tissue exhibiting atrial tachycardia, tissue exhibiting AVNRT, tissue exhibiting PSVT, tissue associated with Wolff-Parkinson-White syndrome, or tumor tissue, among others). The processor 204 or the simulation model generator 302 can identify nodes corresponding to abnormal tissue based on registration of the simulated electrical model to a 3D model of the patient's heart. In particular, the processor 204 or the simulation model generator 302 can identify nodes associated with the ROI and model their parameters accordingly. The processor 204 or simulation model generator 302 can analyze the electrophysiological data 314 to extract measurements of electrical activity in the patient's heart. The measurements of electrical activity can include measurements extracted from ECG data, such as total activation time of the left or right ventricle, QRS duration, electrical axis, QT interval duration, and site-specific activation time, and / or voltage values ​​measured by a catheter device as part of electroanatomical mapping. The one or more processors 204 or simulation model generator 302 can simulate corresponding measurements of electrical activity and compare them to measurements extracted from the electrophysiological data 314. The one or more processors 204 or simulation model generator 302 can modify the conduction velocity and activation signal to minimize differences between the simulated and data-based measurements of electrical activity. For example, an optimal value for conduction velocity in a region of the heart can be estimated using an iterative algorithm, such as BOBYQA.Briefly, multiple candidate values ​​for conduction velocity can be selected, and each selection can generate a corresponding simulated measurement of electrical activity. A new candidate value can be generated based on which conduction velocity value generates a simulated measurement of electrical activity that is closest to the data-based measurement. The algorithm can terminate when the difference between the simulated and data-based measurements of electrical activity falls below a certain threshold or when a maximum number of candidates has been generated. Additional methods for modifying conduction velocity and activity signals to reduce the difference between the simulated and data-based measurements of electrical activity are disclosed in U.S. Patent Nos. 10,733,910, 10,483,005, 10,241,968, and 10,141,077, which are incorporated herein by reference.

[0057] In theory, nodes in a simulated electrical model can represent individual cells in the heart. However, implementing a simulated electrical model at the cellular level results in a very complex model. Modeling the cardiac electrical system at a coarse granularity (e.g., each node corresponds to an individual myocardial block or segment) results in a less complex model while still providing accurate modeling. Typically, adjacent healthy cells of the same type (e.g., contracting myocardial cells) have similar electrical properties.

[0058] The processor 204 or the simulation model generator 302 can register the simulated electrical model to the geometric (or 3D) model. Each node in the simulated electrical model is mapped to its position in the 3D model. The cardiac simulation model includes the 3D model and the registered simulated electrical model. In some embodiments, the processor 204 or the simulation model generator 302 can use other patient data 316 to generate a cardiac simulation model of the patient's heart. For example, the processor 204 or the simulation model generator 302 can use the patient's age or the patient's medical history to estimate one or more model parameters.

[0059] The method 400 may include the processor 204 or the radiation effect estimator 304 determining a simulated post-irradiation state of the patient's heart by adjusting the cardiac simulation model to account for the effect of the radiation treatment plan on the simulated electrical activity of the patient's heart (step 404). The radiation treatment plan may include a radiation dose distribution that specifies the radiation doses to be applied to different regions of the patient's heart. The radiation treatment plan may not be a complete plan at this stage. The radiation effect estimator 304 may receive the radiation treatment plan or the radiation dose distribution from the cardiac radiation treatment planning system 102 or the computing device 112. In some embodiments, the radiation dose distribution may be a radiation dose prescribed by the patient's physician. The radiation effect estimator 304 assumes that radiation was delivered according to the radiation dose distribution and estimates the effect of the hypothetical delivered radiation on the electrical properties or electrical activity of the patient's heart.

[0060] The effects of radiation in an ROI or target volume can be simulated as changes in the electrophysiological properties of cardiac tissue. For example, radiation induces upregulation of cardiac conduction proteins such as NaV1.5 and Cx43, which can be modeled as an increase in conduction velocity. The radiation dose-dependent increase in conduction velocity in an ROI is illustrated, for example, in Figure 3 of Zhang, David M., Rachita Navara, Tiankai Yin, Jeffrey Szymanski, Uri Goldsztejn, Camryn Kenkel, Adam Lang, et al., “Cardiac Radiotherapy Induces Electrical Conduction Reprogramming in the Absence of Transmural Fibrosis,” Nature Communications 12, no. 1 (December 2021): 5558, which is incorporated herein by reference. This paper is hereafter referred to as “Zhang.” The radiation effect estimator 304 can also model new fibrosis potentially generated at high levels of radiation as a reduction in conduction velocity or even zero conduction velocity.

[0061] Experimental results, at least as published in Zhang, may indicate that radiation increases conduction velocity in viable myocardium. Also, relatively high levels of radiation doses cause cell death and electrical inactivity. In other words, if the radiation dose applied to cardiac tissue exceeds a given threshold, the tissue dies and becomes electrically inactive (e.g., it does not respond to electrical simulations, with no electrical capture or propagation of electrical impulses). The radiation dose threshold can be determined from experimental results. Typically, the experimental results may include measured changes in conduction velocity for multiple irradiated radiation doses.

[0062] The processor 204 or the radiation effect estimator 304 can interpolate experimentally measured values. The processor 204 or the radiation effect estimator 304 can estimate or identify a radiation dose threshold that leads to fibrosis or dead tissue. The interpolated experimental results with the identified threshold can be held in one or more data structures, for example, one or more lookup tables or linked lists. The data structures can hold a mapping between radiation dose levels (or values) and corresponding changes in conduction velocity (or corresponding conduction velocity). The data structures can also hold a mapping between radiation dose levels (or values) and corresponding changes in activity signal parameters (or corresponding activity signal parameters). The mapping can include corresponding changes in parameters for each phase of the activity signal parameter (or corresponding parameters for each phase of the activity signal). The variation in the activity signal parameter (with respect to the radiation dose level) can be estimated from the variation in conduction velocity or can be defined based on experimental results measuring the change in the activity signal parameter.

[0063] The processor 204 or radiation effect estimator 304 can identify nodes of the simulated electrical model that belong to the ROI based on, for example, registration of the simulated electrical model to the 3D model and determine the radiation dose associated with the node or corresponding block or portion of the heart based on the radiation dose distribution. For each node within the ROI, the processor 204 or radiation effect estimator 304 can determine the change in conduction velocity and the change in activation signal parameters based on the corresponding radiation dose and one or more mappings maintained in one or more data structures. For each node within the ROI, the processor 204 or radiation effect estimator 304 can update the conduction velocity and parameters of the activation signal. If the activation signal is parameterized by phase, the processor 204 or radiation effect estimator 304 can determine the change in parameters for each phase of the activation signal and update the phase parameters accordingly.

[0064] Updating or adjusting the conduction velocity and activity signal parameters results in an updated or adjusted cardiac simulation model that reflects the effect of the "irradiated" radiation on the electrical properties (or electrical activity) of the heart. In other words, the updated or adjusted cardiac simulation model represents the simulated post-irradiation state of the patient's heart as if it had been irradiated according to the radiation distribution (or radiation therapy treatment plan). The initial conduction velocity and initial activity signal correspond to the simulated pre-irradiation state, while the adjusted conduction velocity and adjusted activity signal correspond to the simulated post-irradiation state of the patient's heart.

[0065] The method 400 may include the processor 204 or the rhythm disorder simulator 306 simulating a post-irradiation state of the patient's heart using a stimulus that induces a cardiac rhythm disorder (step 406). The cardiac rhythm disorder may be associated with at least one of ventricular tachycardia (VT), atrial tachycardia, ventricular fibrillation, atrial fibrillation, or other cardiac pathological conditions. The processor 204 or the rhythm disorder simulator 306 may apply one or more digital catheter-based stimuli to the post-irradiation state of the heart. For example, in practice, a physician would use a catheter to stimulate the heart with a rapid series of stimuli to induce VT. If the irradiation does not fully heal the heart, the heart may begin to contract chaotically, indicating induced VT. Induced VT is a strong predictor of spontaneous post-irradiation VT.

[0066] The processor 204 or rhythm disturbance simulator 306 can digitally simulate the presence of a catheter delivering very fast pacing to the cardiac simulation model. The digital simulation of the presence of a catheter can include applying a fast pulse train to one or more nodes of the cardiac simulation model. The node to which the fast pulse train is applied can depend on the type of cardiac rhythm disturbance to be induced. For example, in the case of VT, the stimulated node corresponds to tissue in the left or right ventricle. In the case of atrial tachycardia, the stimulated node corresponds to tissue in either the left or right atrium.

[0067] The method 400 may include the processor 204 or the rhythm disorder detector 308 determining whether a cardiac rhythm disorder is induced in the simulated post-irradiation state of the heart (step 408). The processor 204 or the rhythm disorder detector 308 may determine whether a cardiac rhythm disorder is induced in the simulated post-irradiation state of the heart based on electrical activity generated when simulating the simulated post-irradiation state of the heart using stimulation. The processor 204 or the rhythm disorder detector 308 may determine or calculate a simulated ECG signal of the cardiac simulation model, for example, as described in U.S. Patent No. 9,463,072, which is incorporated herein by reference. The processor 204 or the rhythm disorder detector 308 may analyze the simulated ECG signal to determine whether a cardiac rhythm disorder is induced in the simulated post-irradiation state of the heart.

[0068] In some embodiments, the processor 204 or the rhythm disorder detector 308 can determine the frequency, period, or autocorrelation signal of the simulated ECG signal. If the frequency, period, or autocorrelation signal does not indicate a normal-period simulated ECG signal, the processor 204 or the rhythm disorder detector 308 can infer that a cardiac rhythm disorder will be induced in the simulated post-irradiation state of the heart. If a cardiac rhythm disorder is induced, this is a strong predictor that the radiation therapy treatment plan will not be effective in healing the heart. In such cases, the radiation treatment plan should be adjusted, or, if the patient has already received radiation according to the simulated radiation treatment plan, the patient should receive additional radiation sessions, for example, with a new radiation treatment plan.

[0069] The method 400 can include the processor 204 or the radiation treatment plan update component 310 outputting an indication of whether a cardiac rhythm disorder is induced in the simulated post-irradiation state of the heart. In some embodiments, the processor 204 or the radiation treatment plan update component 310 can cause a display device, such as the output device 218, to display the simulated ECG signal. A physician can determine whether a cardiac rhythm disorder has been induced based on the simulated ECG signal. In some embodiments, the processor 204 or the radiation treatment plan update component 310 can display a text or visual indicator indicating whether a cardiac rhythm disorder has been induced. The processor 204 or the radiation treatment plan update component 310 can output an audio signal indicating whether a cardiac rhythm disorder has been induced.

[0070] In some embodiments, the processor 204 or the radiation treatment plan update component 310 can recommend or suggest one or more modifications to the radiation treatment plan when it determines that a cardiac rhythm disorder will be induced. The modifications can include modifying the radiation dose for cardiac tissues or ROIs specified in the radiation treatment plan or modifying (e.g., expanding) the ROIs scheduled to receive radiation during the radiation treatment plan. For example, the processor 204 or the radiation treatment plan update component 310 can examine the electrical activity of various nodes in the cardiac simulation model when stimulated to induce a cardiac rhythm disorder. The processor 204 or the radiation treatment plan update component 310 can identify abnormal tissue in the ROIs in the post-radiation state based on the electrical activity of the corresponding nodes. If the electrical activity of some nodes is abnormal, the processor 204 or the radiation treatment plan update component 310 can identify the nodes as abnormal and recommend increasing the radiation dose at the corresponding location or portion in the heart. The processor 204 or the radiation treatment plan update component 310 can examine the electrical activity at nodes corresponding to tissue surrounding the ROI. If the electrical activity of a node or corresponding tissue is determined to be abnormal or disordered, the processor 204 or radiation treatment plan update component 310 can identify the tissue as abnormal or unhealthy and recommend expanding the ROI to include the surrounding tissue.

[0071] After the radiation treatment plan (or radiation dose distribution) is updated, steps 404-410 can be repeated using the updated radiation treatment plan (or radiation dose distribution). In some embodiments, processor 204 can perform steps 404-410 for multiple radiation treatment plans and select a plan that maximizes the likelihood of early termination of cardiac rhythm disorders (or corresponding pathological symptoms) to apply to the patient. The radiation plan that maximizes the likelihood of early termination of VT is selected for implementation to the patient. To estimate the likelihood of early termination of cardiac rhythm disorders (e.g., VT), one possible approach is to count the number of different programmed stimulation strategies that result in sustained or non-sustained cardiac rhythm disorders in a simulated post-irradiation state. Processor 204 can identify the radiation treatment plan that minimizes the number of stimuli that induce cardiac rhythm disorders as the plan that maximizes the likelihood of early termination of cardiac rhythm disorders (or corresponding pathological symptoms).

[0072] In some embodiments, the processor 204 or the radiation treatment plan update component 310 can shrink the ROI (or reduce the radiation dose) if it is determined that a cardiac rhythm disorder will not be induced. The processor 204 can perform steps 404-410 on the updated treatment plan to determine whether a cardiac rhythm disorder will be induced. The processor 204 can continue to shrink the ROI (or reduce the radiation dose) and repeat steps 404-410 until a cardiac rhythm disorder begins to be induced. The processor 204 can select the treatment plan with the smallest ROI (or smallest radiation dose) that did not result in the induction of a cardiac rhythm disorder. In some embodiments, the radiation dose to at least some tissue within the ROI alters the electrical properties of the tissue without destroying or electrically inactivating the tissue.

[0073] In some embodiments, method 400 can be used post-radiation or during a radiation procedure. In such cases, if intra-interventional ECG measurements are available, the estimated conduction velocity in step 404 can be further optimized after each radiation dose to match the ECG-based metric. For example, the conduction velocity at each cardiac site can be scaled by a factor k to reduce the discrepancy between the simulated ECG and the measured ECG. In some embodiments, a first dose delivery session is performed, followed by ECG measurements and corresponding updates of the post-radiation state of the heart. The updated post-radiation state of the heart is used to optimize the dose delivery in subsequent sessions.

[0074] It should be understood that the examples discussed herein are provided for illustrative purposes and should not be construed in a limiting sense. For example, other techniques can be used to estimate or adjust the effect of radiation on the electrical properties of the heart. Also, other types of criteria can be used to determine whether a cardiac rhythm disturbance is included in a simulated post-radiation state.

[0075] Each method described in this disclosure, such as method 400 of Figure 4, may be performed by computer code instructions stored on a computer-readable medium that, when executed by one or more processors of a computing device, cause the computing device to perform the method.

[0076] Although the present disclosure has been particularly shown and described with reference to certain embodiments, it should be understood by those having ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as described in this disclosure.

[0077] While the present disclosure includes details of many specific embodiments, these should not be construed as limitations on the scope of any invention or the scope of the claims, but rather as descriptions of features specific to particular embodiments of a particular invention. Certain features described herein in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment can also be implemented in multiple embodiments individually or in any suitable subcombination. Furthermore, even if features are described above as acting in a particular combination and initially claimed as such, one or more features based on a claimed combination can, in some cases, be separated from the combination, and the claimed combination can be directed to subcombinations or variations of the subcombination.

[0078] Similarly, while operations (tasks, processes, steps) may be depicted in a particular order in the figures, this should not be understood as requiring that the operations be performed in the particular order shown, or in sequential order, or that all of the depicted operations be performed, to achieve desired results. In certain situations, multitasking and parallel processing may be advantageous. Furthermore, the separation of various system components in the above-described embodiments should not be understood as requiring such separation in all embodiments, and it should be understood that the described program components and systems may generally be integrated into a single software product or packaged into multiple software products.

[0079] With respect to "or," any term described using "or" may be construed as inclusive, so that it may refer to either one, more than one, or all of the described terms.

[0080] The foregoing describes specific embodiments of the subject matter. Other embodiments are within the scope of the following claims. In some cases, the functions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may be advantageous.

Claims

1. 1. A method for simulating a radial effect of cardiac ablation, comprising: generating, by one or more processors, a cardiac simulation model of the patient's heart based on medical images and / or electrophysiological data of the patient; the cardiac simulation model is configured to simulate the electrical activity of the patient's heart; determining, by the one or more processors, a simulated post-irradiation state of the patient's heart by adjusting the cardiac simulation model to account for the effect of a radiation treatment plan on the simulated electrical activity of the patient's heart; the radiation treatment plan specifying radiation doses to be applied to different regions of the patient's heart; using the one or more processors to simulate the simulated post-radiation state of the heart with stimulation to induce a cardiac rhythm disorder using the adjusted cardiac simulation model; determining, by the one or more processors, whether the cardiac rhythm disorder is induced based on electrical activity generated when simulating the simulated post-radiation state of the heart with the stimulation; the one or more processors outputting an indication of whether the cardiac rhythm disturbance is induced in the simulated post-irradiation state of the heart; A method comprising:

2. 10. The method of claim 1, wherein the cardiac rhythm disorder is associated with at least one of ventricular tachycardia (VT), atrial tachycardia, ventricular fibrillation, or atrial fibrillation.

3. the electrical activity is defined in the cardiac simulation model using a plurality of parameters of a plurality of electrical activity signals, each of the electrical activity signals being associated with a corresponding region of the patient's heart; adjusting the cardiac simulation model adjusting a parameter of the electrical activity signal associated with a region of the patient's heart that is scheduled to receive radiation during the radiation treatment plan. The method of claim 1.

4. the electrical activity signal has a plurality of phases, each of the phases being defined by one or more corresponding parameters; Adjusting a parameter of the electrical activity signal comprises: determining a change in a parameter of each of the phases of the electrical activity signal due to the effect of the corresponding radiation dose in the region of the heart of the patient scheduled to receive radiation; modifying the parameters for each of the phases of the electrical activity signal in accordance with the determined changes. The method of claim 3.

5. The method of claim 1 , wherein the electrical activity is defined in the cardiac simulation model using one or more parameters of conduction velocity.

6. adjusting the cardiac simulation model modulating at least one parameter of the one or more parameters of the conduction velocity. The method of claim 5.

7. Determining the simulated post-radiation state of the heart includes: identifying tissue of the patient's heart that is predicted to become electrically inactive in response to the radiation treatment plan; The method according to any one of claims 1 to 6.

8. simulating the simulated post-radiation state of the heart using the stimulus to induce the cardiac rhythm disorder includes: simulating virtual catheter-based stimulation in a post-radiation state of the heart; The method according to any one of claims 1 to 6.

9. The method of any one of claims 1 to 6, further comprising suggesting one or more modifications to the radiation therapy plan upon determining that the cardiac rhythm disorder is induced.

10. The one or more modifications to the radiation treatment plan include: modifying the radiation dose to the first region of the heart specified in the radiation treatment plan; or modifying a second region of the heart that is scheduled to receive radiation during the radiation treatment plan.

10. The method of claim 9.

11. 1. A system for simulating a radial effect of cardiac ablation, comprising: one or more processors and a memory for storing computer code instructions; The computer code instructions, when executed, cause the one or more processors to: generating a cardiac simulation model of the patient's heart based on medical images and / or electrophysiological data of the patient; the cardiac simulation model is configured to simulate the electrical activity of the patient's heart; determining a simulated post-irradiation state of the heart by adjusting the cardiac simulation model to account for the effect of a radiation treatment plan on the simulated electrical activity of the patient's heart; the radiation treatment plan specifying radiation doses to be applied to different regions of the patient's heart; using the adjusted cardiac simulation model to simulate the simulated post-radiation state of the heart involving a stimulus that induces a cardiac rhythm disorder; determining whether the cardiac rhythm disturbance is induced in the simulated post-irradiation state of the patient's heart; outputting an indication of whether the cardiac rhythm disturbance is induced in the simulated post-irradiation state of the patient's heart. system.

12. 12. The system of claim 11, wherein the cardiac rhythm disorder is associated with at least one of ventricular tachycardia (VT), atrial tachycardia, ventricular fibrillation, or atrial fibrillation.

13. the electrical activity is defined in the cardiac simulation model using a plurality of parameters of a plurality of electrical activity signals, each of the electrical activity signals being associated with a corresponding region of the patient's heart; When adjusting the cardiac simulation model, adjusting a parameter of the electrical activity signal associated with a region of the patient's heart that is scheduled to receive radiation during the radiation treatment plan. The system of claim 11.

14. each of the electrical activity signals having a plurality of phases, each of the phases being defined by one or more corresponding parameters; When adjusting parameters of the electrical activity signal, the one or more processors: determining a change in a parameter of each of the phases of the electrical activity signal due to the effect of the corresponding radiation dose in the region of the heart of the patient scheduled to receive radiation; modifying the parameters for each of the phases of the electrical activity signal in accordance with the determined changes. The system of claim 13.

15. The system of claim 11 , wherein the electrical activity is defined in the cardiac simulation model using one or more parameters of conduction velocity.

16. When adjusting the cardiac simulation model, the one or more processors: configured to modulate at least one parameter of the one or more parameters of the conduction velocity.

16. The system of claim 15.

17. When determining the simulated post-radiation state of the heart, the one or more processors: configured to identify tissue of the patient's heart that is predicted to become electrically inactive in response to the radiation treatment plan. A system according to any one of claims 11 to 16.

18. When simulating the simulated post-radiation state of the heart using the stimulus to induce the cardiac rhythm disorder, the one or more processors: configured to simulate virtual catheter-based stimulation in a post-radiation state of the patient's heart. A system according to any one of claims 11 to 16.

19. The one or more processors: and further configured to suggest one or more modifications to the radiation treatment plan upon determining that the cardiac rhythm disorder is induced. A system according to any one of claims 11 to 16.

20. The one or more modifications to the radiation treatment plan include: modifying the radiation dose to the first region of the heart specified in the radiation treatment plan; or modifying a second region of the heart that is scheduled to receive radiation during the radiation therapy plan.

20. The system of claim 19.

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