A Multifunctional Non-Contact Three-Dimensional Mapping System for Cardiac Electrophysiology Based on ICE

Abstract

This invention discloses a multifunctional non-contact three-dimensional cardiac electrophysiological mapping system based on intracardiac ultrasound (ICE), comprising an ICE system, an ultrasound host, an ECG signal acquisition system, and a three-dimensional spatial positioning system. By adjusting the position and imaging angle of the ICE probe, it continuously acquires cardiac ultrasound signals, as well as heartbeat and respiratory signals, to synchronously acquire ultrasound signals at different cardiac cycles. Cross-correlation calculations are performed on the continuous ultrasound signals acquired at various spatial locations to obtain the three-dimensional cardiac excitation conduction sequence and maximum amplitude distribution within a cardiac cycle. This system can perform both intracardiac ultrasound imaging and non-contact three-dimensional electrophysiological mapping, reducing the use of catheters and medical costs in traditional contact electrophysiological interventional procedures, simplifying surgical operations, and improving surgical safety. Furthermore, it can simultaneously map the endocardium, intramyocardium, and epicardium, enabling more precise surgical planning and possessing significant clinical value.

Description

Technical Field

[0001] This invention relates to the field of three-dimensional mapping technology for intracardiac catheters, and more particularly to a multifunctional non-contact three-dimensional mapping system for cardiac electrophysiology based on ICE. Background Technology

[0002] Current three-dimensional electrophysiological mapping of the heart often requires the use of multiple multi-electrode mapping catheters, which are inserted into the heart chambers via femoral vein puncture to directly measure the electrical potential of the endocardium. However, this method has drawbacks. First, due to the complex three-dimensional structure of the heart, multiple mapping catheters of different shapes are usually required to achieve better endocardial adhesion. A single mapping catheter typically costs around 20,000 RMB and is for single use, resulting in high costs. Second, the lesion matrix in electrophysiological cardiology exists simultaneously in the endocardium, epicardium, and myocardium. Catheter intervention can only contact the inner wall of the heart; therefore, contact mapping can only locate lesions located in the endocardium and cannot reach the epicardium or intramyocardial tissues, and the procedure is complex. Therefore, how to reduce medical costs and achieve simultaneous mapping of the endocardium, intramyocardium, and epicardium remains to be solved. Summary of the Invention

[0003] The main objective of this invention is to provide a multifunctional non-contact three-dimensional ultrasound mapping system based on ICE (Intra-Intra-Cyclic Echocardiography). This system includes two modes: imaging mode and three-dimensional cardiac electrophysiological mapping mode, enabling it to perform both ICE imaging and three-dimensional cardiac mapping. Its three-dimensional mapping mode solves the problems of existing technologies that require the use of multiple mapping catheters of different shapes for three-dimensional mapping and cannot simultaneously map the endocardium, intramyocardium, and epicardium.

[0004] To achieve the above objectives, the first aspect of the present invention provides a multifunctional non-contact three-dimensional ultrasound mapping system based on ICE, the system comprising an ICE catheter, an ultrasound host, and an ECG electrocardiogram signal acquisition system:

[0005] The ICE catheter includes a catheter body, an ICE probe, and a handle or motor. The handle or motor is used to adjust the position of the ICE probe and the imaging field of view. The ICE probe is used to acquire ultrasound signals from different spatial locations within the heart chamber and send the acquired ultrasound signals to the ultrasound host. The ultrasound signals include signals continuously acquired by the ICE probe within one heartbeat cycle.

[0006] The ultrasound host is used to perform cross-correlation calculations on ultrasound signals continuously acquired at the same spatial location to identify the cardiac excitation start time and maximum amplitude at the spatial location, thereby obtaining a three-dimensional excitation conduction sequence diagram and a three-dimensional maximum amplitude distribution of cardiac excitation at each spatial location within a cardiac cycle.

[0007] The ECG signal acquisition system is used to acquire electrical signals from the body surface and identify ECG and respiratory signals, thereby identifying the resting state of the heart. It also performs time synchronization on ultrasound signals acquired at different spatial locations to obtain the relative excitation time between the resting states of the heart at each spatial location, where the heart's resting state is the moment when end-diastole and end-expiration overlap.

[0008] In conjunction with the first aspect, in one possible implementation, the ICE catheter is used to traverse all spatial locations within the heart chamber by adjusting the position and imaging field of the ICE probe; at the traversed spatial locations, ultrasound signals are continuously acquired within one heartbeat cycle to obtain ultrasound signals for all spatial locations within one complete heartbeat cycle.

[0009] In conjunction with the first aspect, in one possible implementation, the ultrasound host is also used to synchronize the resting state of the heart at various spatial locations, taking the resting state time as the starting time and the relative excitation time of each spatial location as the start time of cardiac excitation at each spatial location within a heartbeat cycle, thereby obtaining a three-dimensional excitation conduction sequence.

[0010] In conjunction with the first aspect, in one possible implementation, the ultrasound host is specifically used to traverse and scan different target spatial locations, where the target spatial location is any one of the spatial locations;

[0011] The ultrasonic signals of the nth ultrasonic echo beam and the (n+1)th ultrasonic echo beam traversing to the target spatial position are respectively acquired at the mth beam position. The excitation displacement of the ultrasonic signal at the mth beam position is obtained by cross-correlation calculation. The initial value of m is 1, and the value ranges from 1 to M, where M is the total number of beam positions scanned.

[0012] Let n = n + 1, return to the step of traversing the N consecutive time intervals of the target spatial location, until n = N - 1, to obtain the maximum excitation amplitude of the target spatial location and the start time of cardiac excitation relative to the resting state of the heart, where N is the total number of ultrasound echo beams received at the target spatial location.

[0013] In conjunction with the first aspect, in one possible implementation, the ultrasound host is used to dynamically display the three-dimensional excitation conduction sequence in three dimensions, and simultaneously dynamically display the maximum excitation amplitude at each spatial location in three dimensions, thereby obtaining a three-dimensional cardiac excitation conduction sequence diagram and the maximum amplitude distribution.

[0014] In conjunction with the first aspect, in one possible implementation, the ECG surface electrocardiogram signal acquisition system is also used to record the acquisition time of ultrasound signals at various spatial locations within a heartbeat cycle.

[0015] In conjunction with the first aspect, in one possible implementation, the ICE catheter further includes a three-dimensional positioning sensor, which is fixed to the ICE probe. The three-dimensional positioning sensor is used to obtain the three-dimensional spatial position and imaging angle of the probe, thereby locating the position of the ultrasonic beam and the spatial position of the abnormal transmission of excitation.

[0016] In conjunction with the first aspect, in one possible implementation, the system can function as both an ICE imaging system for ultrasound imaging of the heart and for obtaining B-mode images of the heart and performing blood flow imaging, and as a non-contact mapping system for performing three-dimensional mapping of cardiac electrophysiology.

[0017] In conjunction with the first aspect, in one possible implementation, the ICE ultrasonic probe is configured as a single-element probe, a linear array ultrasonic probe, a phased linear array ultrasonic probe, a surface array probe, a ring array probe, or a mechanically rotating linear array probe; and is configured as a PZT ceramic material, a composite material, a CMUT, or a PMUT material.

[0018] In conjunction with the first aspect, in one possible implementation, the ICE catheter has a communication connection with the ultrasound host, and the ultrasound host has a communication connection with the ECG surface electrocardiogram signal acquisition system.

[0019] The embodiments of the present invention have the following beneficial effects: The ICE catheter is used to sequentially acquire ultrasound signals at different spatial locations within the heart chamber by adjusting the spatial position imaging field of the ICE probe, and sends the ultrasound signals to the ultrasound host. The ultrasound signals include signals continuously acquired within one heartbeat cycle. The ECG surface electrocardiogram signal acquisition system is used to measure the surface cardiac electrophysiological signals at different spatial locations to obtain the resting state time of the heart at each spatial location, which is used to synchronize the ultrasound acquisition time to obtain the heart excitation start time at each spatial location. The relative excitation start time at each spatial location is obtained based on the end time of the resting state and the heart excitation start time. The ultrasound host is used to obtain multiple consecutive ultrasound beams at each spatial location based on the ultrasound signals at each spatial location, obtain the excitation amplitude at each spatial location based on multiple consecutive echo beams at each spatial location, and obtain the three-dimensional excitation conduction sequence and the maximum amplitude distribution of three-dimensional cardiac excitation at each spatial location within one heartbeat cycle based on the relative excitation start time and the maximum excitation amplitude. In this technical solution, the ICE catheter includes an imaging mode and a three-dimensional mapping mode. It can be used as a conventional intracardiac ultrasound probe or as a three-dimensional mapping catheter, thereby reducing the number of catheters required for electrophysiological interventional surgery, lowering medical costs, and simplifying surgical procedures. Secondly, using the ICE probe for ultrasound imaging, since ultrasound has the ability to penetrate the endocardium, myocardium, and epicardium, it can simultaneously map the endocardium, myocardium, and epicardium, improving the amount of information obtained from the three-dimensional excitation conduction sequence and the maximum amplitude map of three-dimensional cardiac excitation, as well as the reliability of the surgery. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] in:

[0022] Figure 1 This is a schematic diagram of the structure of a cardiac electrophysiology three-dimensional mapping system based on ICE in an embodiment of the present invention;

[0023] Figure 2 This is a flowchart illustrating a method for a cardiac electrophysiological three-dimensional mapping system based on ICE in an embodiment of the present invention.

[0024] Figure 3 This is a structural block diagram of a computer device in an embodiment of the present invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] Electrophysiological cardiology, also known as arrhythmic heart disease, is a significant clinical problem. It typically results from abnormal cardiac charge transport, leading to abnormal amplitude and conduction sequence of myocardial cell depolarization and repolarization, thus causing serious clinical conditions (including atrial fibrillation, supraventricular tachycardia, and ventricular arrhythmias). Catheter-guided three-dimensional electrophysiological mapping of intracardiac potentials to locate lesions and then ablating these target lesions is currently the safest and most effective first-line treatment for electrophysiological cardiology. Three-dimensional electrophysiological mapping is the most challenging aspect of this procedure. It typically uses intracardiac measuring electrodes to measure the potential transported through the endocardium, obtaining a three-dimensional cardiac activation timing map and a three-dimensional maximum amplitude map of cardiac activation on the endocardium. This guides the physician to locate the target site of abnormal activation transport and perform ablation treatment for arrhythmic heart disease.

[0027] This embodiment provides a three-dimensional cardiac electrophysiological mapping system based on ICE (Intracardiac Echocardiography) to obtain the three-dimensional impulse conduction sequence and the three-dimensional maximum amplitude distribution of cardiac impulses, thereby improving the accuracy of target localization for abnormal impulse transmission. (Refer to...) Figure 1 , Figure 1 This embodiment provides a structural schematic diagram of a multifunctional non-contact three-dimensional ultrasonic mapping system based on ICE. Figure 1 As shown, the cardiac electrophysiological three-dimensional mapping system includes an ICE catheter 10, an ultrasound host 20, and an ECG surface electrocardiogram signal acquisition system 30. The ICE catheter 10 and the ultrasound host 20 are connected via communication, as are the ultrasound host 20 and the ECG surface electrocardiogram signal acquisition system 30. This communication connection can be wireless or wired. The ICE catheter 10 includes an ICE probe, a catheter body, and a handle (or motor). The handle or motor is used to adjust the position and imaging field of the ICE probe. The ICE probe is used to acquire ultrasound signals from different spatial locations within the cardiac chambers and transmit the acquired ultrasound signals to the ultrasound host. The ICE catheter also includes a three-dimensional positioning sensor, which is fixed to the ICE probe. This three-dimensional positioning sensor is used to obtain the three-dimensional spatial position and imaging angle of the probe, thereby locating the position of the ultrasound beam and the spatial location of abnormal excitation transmission.

[0028] The following explanation, based on the aforementioned three-dimensional cardiac electrophysiological mapping system, illustrates how to obtain the three-dimensional excitation conduction sequence and the three-dimensional maximum amplitude distribution of cardiac excitation, referring to... Figure 2 , Figure 2 This is a schematic diagram illustrating the implementation method of a multifunctional non-contact three-dimensional ultrasonic mapping system based on ICE provided in this embodiment, as shown below. Figure 2 As shown, the specific steps of this method are as follows:

[0029] Step S101: By adjusting the imaging field of the ICE probe, ultrasound signals at different spatial locations within the heart chambers are acquired sequentially.

[0030] Step S102: Obtain respiratory and electrocardiogram signals through surface electrodes as synchronization time signals for ultrasound signals acquired within different heartbeat cycles.

[0031] Step S103: Perform cross-correlation calculation on the ultrasound signals continuously acquired at the same spatial location to identify the heartbeat excitation start time and maximum amplitude at the spatial location.

[0032] Step S104: Based on the relative excitation time and maximum amplitude of each spatial location, obtain the three-dimensional excitation conduction sequence diagram and the three-dimensional maximum amplitude distribution of cardiac excitation within one heartbeat cycle for each spatial location.

[0033] The ultrasound signal includes signals continuously acquired within a heartbeat cycle. A heartbeat cycle refers to a mechanical wave propagation cycle consisting of each contraction and relaxation of the heart. The resting state of the heart is the moment when the end of diastole and the end of expiration overlap.

[0034] In this embodiment, the imaging field of view of the ICE probe is not fixed. It can be changed by deflecting or mechanically rotating the ICE probe. Specifically, rotating the ICE probe can be achieved using a handle connected to the ICE catheter. The handle changes the spatial orientation and angle of the ICE probe to adjust its imaging field of view. Alternatively, a motor can be used to adjust the imaging angle of the ICE probe. Clearly, different imaging fields correspond to different spatial locations within the heart. Based on the above, in this embodiment, ultrasound signals from various spatial locations within the heart chambers are acquired by changing the imaging field of the ICE probe. Furthermore, although this patent uses a motor to adjust the imaging angle of the ICE probe, the probe angle can also be adjusted by operating the proximal handle.

[0035] In this embodiment, the ICE probe can function as both an ICE imaging system for ultrasound imaging of the heart, obtaining B-mode images of the heart, and performing blood flow imaging for diagnosis, surgical monitoring, and surgical guidance; and as a non-contact mapping system for three-dimensional mapping of cardiac electrophysiology. In imaging mode, this system is equivalent to a conventional intracardiac ultrasound ICE system.

[0036] Among them, ICE probes can be classified according to their structure as single-element probes, linear array ultrasound probes, phased array ultrasound probes, area array probes, ring array probes, and mechanically rotating linear array probes. They can also be classified according to the materials used, such as PZT ceramic, composite materials, CMUT, or PMUT. Linear array ultrasound probes and rotating linear array probes typically have a 90° field of view, while area array probes typically have a 90°-90° field of view. The parameters of linear array ultrasound probes are not limited; different frequencies, number of elements, element spacing, and element distribution schemes can be selected according to various application environments. Rotating linear array probes can use combinations of more than one linear array transducer (such as multiple linear array probes bonded at a certain angle) to further improve the speed of 4D scanning. Furthermore, rotating linear array probes can perform 3D scanning by rotating the probe via a motor, enabling automatic 360° cardiac scanning. Rotating linear array probes can rotate unidirectionally or bidirectionally.

[0037] Meanwhile, the ultrasonic probe can be a traditional PZT piezoelectric ceramic, or a single crystal piezoelectric ceramic probe, a capacitive piezoelectric transducer (CMUT), or a piezoelectric micromechanical transducer (PMUT) probe. The transducer array can emit sound waves by sequentially emitting multiple focused ultrasonic beams for planar scanning, or by sequentially emitting multiple non-focused plane waves or divergent waves for planar scanning.

[0038] Step S1011: By adjusting the imaging field of view of the ICE probe, all spatial positions within the heart cavity are traversed. At the traversed spatial positions, ultrasound signals are continuously acquired within one heartbeat cycle to obtain continuous ultrasound signals at the traversed spatial positions within the heartbeat cycle.

[0039] In this embodiment, continuous ultrasound signals at various spatial locations within the cardiac chambers are acquired by changing the imaging field of view of the ICE probe, as detailed below:

[0040] An ICE probe is inserted into the heart chamber via femoral vein intervention. The imaging field of the ICE probe is aligned with the first spatial position, and the first spatial position is scanned. Specifically, for the first spatial position, ultrasound signals are continuously and rapidly acquired within one heartbeat cycle to obtain continuous ultrasound signals for the first spatial position.

[0041] After the ultrasound signal in one heartbeat cycle at the first spatial location is acquired, rotate the imaging field of the ICE probe to acquire the ultrasound signal at the second spatial location. Repeat the above operation until the ultrasound signals at all spatial locations within the heart are acquired. This gives the ultrasound signal for each spatial location in one heartbeat cycle.

[0042] For example, there are three spatial locations within the heart: the first, second, and third spatial locations. First, the imaging field of the ICE probe is aligned with the first spatial location, and ultrasound signals are continuously and rapidly acquired within one heartbeat cycle to obtain the ultrasound signal for the first spatial location within one heartbeat cycle. After acquiring the ultrasound signal for the first spatial location, the imaging field of the ICE probe is rotated to align with the second spatial location, and ultrasound signals are continuously and rapidly acquired within one heartbeat cycle to obtain the ultrasound signal for the second spatial location within one heartbeat cycle. After acquiring the ultrasound signal for the second spatial location, the imaging field of the ICE probe is rotated to align with the third spatial location, and ultrasound signals are continuously and rapidly acquired within one heartbeat cycle to obtain the ultrasound signal for the third spatial location within one heartbeat cycle. In this way, the ultrasound signals for each spatial location within one corresponding heartbeat cycle can be obtained.

[0043] This embodiment uses a single multifunctional ICE probe to perform ultrasound structural and blood flow imaging, achieving the functions of a traditional ICE probe, as well as non-contact ultrasound electrophysiological three-dimensional mapping. This effectively reduces the use of catheters during electrophysiological interventional surgery, lowers medical costs, and simplifies surgical procedures.

[0044] In this embodiment, since the ICE probe is located inside the heart, its imaging effect is better than that of transthoracic ultrasound. At the same time, its imaging field of view is not obstructed by ribs or other obstructions, and it can obtain three-dimensional mapping of the whole heart. In addition, the use of a rotating ultrasound probe for three-dimensional mapping of the heart can automatically perform a 360° heart scan and obtain the three-dimensional mapping results of the heart in a fully automatic manner.

[0045] In this technical solution, the objective is to obtain the excitation conduction sequence and the maximum amplitude distribution of three-dimensional cardiac excitation at each spatial location within a heartbeat cycle. In this embodiment, the three-dimensional excitation conduction sequence is determined by the ultrasound host based on the relative excitation time at each spatial location. This three-dimensional excitation conduction sequence refers to the propagation sequence of cardiac excitation mechanical waves at each spatial location within a heartbeat cycle. The maximum amplitude distribution of three-dimensional cardiac excitation is determined by the ultrasound host based on the maximum excitation amplitude at each spatial location combined with the three-dimensional excitation conduction sequence.

[0046] The following section will first introduce how to obtain the relative excitation time of each spatial location and how to obtain the three-dimensional excitation conduction sequence based on the relative excitation time.

[0047] In this embodiment, the relative excitation time at each spatial location is obtained by the ECG surface electrocardiogram signal acquisition system. The relative excitation time refers to the time difference between the start of cardiac excitation and the resting state of the heart. The resting state of the heart is the moment when the end of diastole and the end of expiration overlap. Therefore, the ECG surface electrocardiogram signal acquisition system needs to acquire the start of cardiac excitation and the resting state of the heart respectively.

[0048] The cardiac resting state generally refers to the moment when the heart is at its slowest, that is, the moment when the end of diastole and the end of expiration overlap. This cardiac resting state can be identified based on surface cardiac electrophysiological signals, while simultaneously reading heartbeat and respiratory signals. In this embodiment, the ECG surface electrocardiogram signal acquisition system measures surface cardiac electrophysiological signals to determine the cardiac resting state. Based on this spatial location's cardiac resting state and the ultrasound signal acquisition time, the ECG surface electrocardiogram signal acquisition system also records the acquisition time of ultrasound signals at each spatial location within one heartbeat cycle, obtaining the ultrasound acquisition time relative to the cardiac resting state. This patent assumes that respiration and heartbeat are constant. Therefore, by synchronizing signals acquired at different heartbeat and respiratory cycles to the same heartbeat cycle through ECG gating, and based on the synchronized time, cross-correlation calculations can be used to identify the activation start time at different cardiac locations and the maximum activation amplitude at different locations within one heartbeat cycle.

[0049] The steps of the cross-correlation calculation are as follows: Based on the ultrasound signals of the ultrasound beam positions at every two adjacent moments acquired at the target spatial location, these are treated as a beam group. Cross-correlation calculations are performed to obtain the cross-correlation coefficient and signal displacement. If the signal displacement exceeds a certain threshold, cardiac excitation is considered to have occurred. Simultaneously, the maximum displacement calculated from the continuous beam group within one cardiac cycle is calculated; this is the maximum excitation amplitude at the target spatial location. It should be noted that, because the maximum excitation amplitude is to be obtained at each spatial location, the target spatial location is any one of all spatial locations. By rotating and deflecting the catheter, the beam group at the target spatial location is traversed, achieving three-dimensional mapping of all spatial locations throughout the heart.

[0050] Step S1021: Traverse the spatial locations, obtain the cardiac excitation start time and the synchronized ultrasound signal acquisition time of the traversed spatial locations, calculate the relative excitation time between the cardiac excitation start time and the cardiac resting state, and obtain the relative excitation time corresponding to each spatial location.

[0051] After determining the resting state of the heart and the start time of cardiac excitation at each spatial location, the ECG signal acquisition system calculates the time difference between the ultrasound signal acquisition time and the resting state of the heart at the same spatial location, thus obtaining the relative excitation time after time synchronization at that spatial location. By this method, the relative excitation time of each spatial location can be obtained.

[0052] Assume there are three spatial locations within the heart: the first, second, and third spatial locations. For the first spatial location, there is a resting state t1 and a cardiac activation start time t2, where t1 = 0.1s and t2 = 0.3s. Arranged in ascending order, these are t1 and t2. The relative time between each cardiac activation start time at the first spatial location and the previous resting state is obtained; the relative activation time between t1 and t2 is 0.2s. For the second spatial location, there is a resting state t3 and a cardiac activation start time t4, where t3 = 0.8s and t4 = 1.1s. The relative activation time between t3 and t4 is 0.3s. For the third spatial location, there is a resting state t5 and a cardiac activation start time t6, where t5 = 1.3s and t6 = 1.7s. The relative activation time between t5 and t6 is 0.4s.

[0053] Step S1031: Synchronize the resting state of the heart at each spatial location, take the resting state of the heart as the starting time, and take the relative excitation time of each spatial location as the start time of cardiac excitation at each spatial location within a heartbeat cycle, to obtain the three-dimensional excitation conduction sequence.

[0054] Furthermore, the ECG surface electrocardiogram signal acquisition system sends the relative excitation times of each spatial location to the ultrasound host. The ultrasound host determines the three-dimensional excitation conduction sequence by using the relative excitation times of each spatial location of the heart.

[0055] Following the previous example of how an ECG surface electrocardiogram signal acquisition system obtains the relative excitation time corresponding to each spatial location, the following describes how an ultrasound host obtains the propagation sequence of cardiac excitation at each spatial location within a heartbeat cycle based on the relative excitation time:

[0056] Synchronize the resting state of the heart at various spatial locations to the same moment and use that moment as the starting moment. For example, synchronize the resting state moments t1, t3, and t5 of the heart at the first spatial location to the starting moment within a heartbeat cycle. Based on the starting moment and the relative excitation time of each spatial location, the arrangement of the cardiac excitation start times at each spatial location can be obtained. The arrangement of the cardiac excitation start times at each spatial location is used as the propagation order of cardiac excitation at each spatial location within a heartbeat cycle.

[0057] For example, based on the fact that the relative excitation time between t1 and t2 at the first spatial position is 0.2s, the relative excitation time between t3 and t4 at the second spatial position is 0.3s, and the relative excitation time between t5 and t6 at the third spatial position is 0.4s, we can obtain that the cardiac excitation start times at the first, second, and third spatial positions are 0.2s, 0.3s, and 0.4s, respectively. In other words, the propagation order of cardiac excitation at each spatial position in one heartbeat cycle is from the first spatial position to the second spatial position and then to the third spatial position.

[0058] The above describes how an ultrasound host obtains the three-dimensional excitation conduction sequence based on relative excitation time. The following describes how an ultrasound host obtains the maximum excitation amplitude at each spatial location.

[0059] Step S1032: Traverse and scan different target spatial locations, where the target spatial location is any one of the spatial locations; respectively acquire the ultrasound signals of the nth ultrasound echo beam and the (n+1)th ultrasound echo beam at the mth beam position traversed to the target spatial location, and calculate the excitation displacement of the ultrasound signal at the mth beam position through cross-correlation calculation, where the initial value of m is 1, and the value ranges from 1 to M, where M is the total number of scanned beam positions; let n = n+1, return to the step of acquiring the ultrasound signals of the nth ultrasound echo beam and the (n+1)th ultrasound echo beam at the mth beam position traversed to the target spatial location, until n = N-1, to obtain the maximum excitation amplitude of the target spatial location and the cardiac excitation start time relative to the resting state of the heart.

[0060] Where N is the total number of ultrasonic echo beams received at the target spatial location.

[0061] Specifically, the process involves traversing N ultrasonic beam positions at the target spatial location, where the ultrasonic beam group consists of the nth ultrasonic beam and the (n+1)th ultrasonic beam, and the target spatial location is any one of the spatial locations. The ultrasonic signals of the ultrasonic beam at time n and time (n+1) at the m-th beam position are obtained respectively. The excitation displacement of the ultrasonic signal at the m-th beam position is calculated through cross-correlation, where m is initially 1 and ranges from 1 to M, where M is the total number of beam positions. Then, n = n+1, and the process returns to the steps of traversing the N ultrasonic beams at the target spatial location until n = N-1, obtaining the maximum excitation amplitude at the target spatial location.

[0062] In this embodiment, the ICE catheter sends the collected ultrasound signals to the ultrasound host. After receiving the ultrasound signals from the ICE catheter, the ultrasound host obtains multiple consecutive ultrasound beam signals at the same spatial location based on the ultrasound signals at the same spatial location.

[0063] The following example, using the acquisition of the maximum excitation amplitude at the first spatial location, illustrates how the ultrasound host obtains the maximum excitation amplitude at a spatial location.

[0064] Assuming that three ultrasonic beams are continuously acquired at the first spatial location, each pair of adjacent ultrasonic beams is taken as a beam group. That is, the first ultrasonic beam S1 and the second ultrasonic beam S2 are taken as the first beam group, and the second ultrasonic beam S2 and the third ultrasonic beam S3 are taken as the second beam group.

[0065] The process iterates through the first and second beam groups. First, the first and second ultrasonic beams in the first beam group are acquired. Cross-correlation calculations are then performed to obtain the excitation displacement of the ultrasonic signal along the first beam position from imaging time t1 to imaging time t2, and the cross-correlation coefficient. After obtaining the excitation displacement in the first beam group, the same operation is performed on the second beam group. The second and third ultrasonic beams in the second beam group are acquired. Cross-correlation calculations are then performed to obtain the excitation displacement and cross-correlation coefficient of these ultrasonic signals along the first beam position from imaging time t2 to imaging time t3. Finally, two consecutive ultrasonic beams in the second beam group are acquired, and cross-correlation calculations are performed to obtain their excitation displacement and cross-correlation coefficient.

[0066] Among them, t1, t2, and t3 can be obtained by the ECG surface electrocardiogram signal acquisition system. In this embodiment, when the ICE probe acquires ultrasound signals at various spatial locations, the ECG surface electrocardiogram signal acquisition system can record the time of each ultrasound signal acquisition, which can be recorded as t1, t2, t3, ..., tN respectively.

[0067] Based on the maximum displacement of multiple consecutive ultrasonic beam groups at the first spatial position obtained by cross-correlation calculation, the maximum excitation amplitude of the first spatial position within one heartbeat cycle is obtained.

[0068] By processing multiple frames of ultrasound images at various spatial locations using the method described above, the maximum excitation amplitude at each spatial location can be obtained.

[0069] During surgery, doctors are concerned with the sequence of excitation conduction at each spatial location within a heartbeat cycle. However, the excitation currently acquired is obtained by collecting signals and calculating them at different heartbeat cycles. Therefore, it is necessary to synchronize the excitation start time measured at each spatial location within different heartbeat cycles to synchronize the conduction of three-dimensional cardiac excitation at each spatial location within a heartbeat cycle.

[0070] Step S1033: Display the three-dimensional excitation conduction sequence in three-dimensional dynamic form, and display the maximum excitation amplitude at each spatial location in three-dimensional dynamic form to obtain a three-dimensional cardiac excitation conduction sequence diagram and the maximum amplitude distribution.

[0071] The ultrasound system performs image segmentation and resting 3D modeling on multiple frames of ultrasound images of the heart at different spatial locations in a resting state, and displays the 3D impulse conduction sequence and maximum impulse amplitude on the 3D model. Image segmentation can be based on AI or traditional image segmentation algorithms, and the resting 3D modeling algorithm can be the Marching Cube algorithm, crust-based surface reconstruction algorithm, or other algorithms. Specifically, based on the 3D modeling, the obtained impulse conduction maps and maximum impulse amplitude displays at each spatial location are synchronized to the ultrasound images in a resting state for dynamic 3D display, thereby obtaining the complete 3D cardiac impulse sequence and maximum amplitude distribution of a cardiac cycle. To improve the resolution of the 3D spatial display, a 3D interpolation algorithm can be used.

[0072] Because ultrasound has the ability to penetrate tissues, it can penetrate the endocardium, myocardium, and epicardium from within the heart chambers. Therefore, the ultrasound-based three-dimensional ultrasound mapping system in this embodiment can obtain the excitation signals of the endocardium, myocardium, and epicardium based on the ultrasound signals that penetrate the heart tissue, thereby increasing the amount of information on the maximum amplitude distribution of the obtained three-dimensional cardiac excitation and providing more clinical information.

[0073] In this embodiment, a three-dimensional positioning sensor is further used to locate the spatial location of abnormal excitation transmission based on the pathogenesis and the three-dimensional excitation conduction sequence and the maximum amplitude distribution of three-dimensional cardiac excitation obtained from the above steps, guiding the doctor to perform ablation surgery. If magnetic field positioning is used, the host system consists of a magnetic field generator and a PIU (Patient Interface Unit).

[0074] In this technical solution, an ICE probe is used to acquire ultrasound signals and obtain images, thereby achieving an imaging mode. Secondly, based on the ultrasound signals acquired by the ICE probe, the relative time obtained by the ECG signal acquisition system, and combined with the cardiac activation start time and maximum amplitude value identified by the ultrasound host at the spatial location, a three-dimensional activation conduction sequence diagram and a three-dimensional maximum amplitude distribution of cardiac activation are obtained, thus achieving a three-dimensional mapping mode. The ICE catheter in this system can be used as a conventional intracardiac ultrasound probe or as a three-dimensional mapping catheter, thereby reducing the number of catheters required for electrophysiological interventional surgery, lowering medical costs, and simplifying surgical procedures. Furthermore, using an ICE probe for ultrasound imaging, because ultrasound has the ability to penetrate the endocardium, myocardium, and epicardium, allows for simultaneous mapping of the endocardium, myocardium, and epicardium, improving the information content and surgical reliability of the obtained three-dimensional activation conduction sequence and three-dimensional maximum amplitude diagram of cardiac activation.

[0075] Figure 3 An internal structural diagram of a computer device in one embodiment is shown. This computer device can specifically be a terminal or a server. Figure 3 As shown, the computer device includes a processor, a memory, and a data transfer interface connected via a system bus. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium stores an operating system and may also store a computer program. When executed by the processor, the computer program causes the processor to perform the steps in the above-described method embodiments. The internal memory may also store a computer program, which, when executed by the processor, causes the processor to perform the steps in the above-described method embodiments. Those skilled in the art will understand that... Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0076] In one embodiment, a computer device is provided, including a memory and a processor, the memory storing a computer program that, when executed by the processor, causes the processor to perform the steps in the above method embodiments.

[0077] In one embodiment, a computer-readable storage medium is provided storing a computer program that, when executed by a processor, causes the processor to perform the steps in the above method embodiments.

[0078] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments described above. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0079] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A multifunctional non-contact three-dimensional cardiac electrophysiological mapping system based on ICE, characterized in that, The system includes an ICE catheter, an ultrasound host, and an ECG electrocardiogram signal acquisition system. The ICE catheter includes a catheter body, an ICE probe, and a handle or motor. The handle or motor is used to adjust the position of the ICE probe and the imaging field of view. The ICE probe is used to acquire ultrasound signals from different spatial locations within the heart chamber and send the acquired ultrasound signals to the ultrasound host. The ultrasound signals include signals continuously acquired by the ICE probe within one heartbeat cycle. The ultrasound host is used to perform cross-correlation calculations on ultrasound signals continuously acquired at the same spatial location to identify the cardiac excitation start time and maximum amplitude at the spatial location, thereby obtaining a three-dimensional excitation conduction sequence diagram and a three-dimensional maximum amplitude distribution of cardiac excitation at each spatial location within a cardiac cycle. The ECG signal acquisition system is used to acquire electrical signals from the body surface and identify ECG and respiratory signals, thereby identifying the resting state of the heart. It also performs time synchronization on ultrasound signals acquired at different spatial locations to obtain the relative excitation time between the resting states of the heart at each spatial location, where the heart's resting state is the moment when end-diastole and end-expiration overlap. in, The ICE catheter is used to traverse all spatial locations within the heart chambers by adjusting the position of the ICE probe and the imaging field of view; At each of the traversed spatial locations, ultrasound signals are continuously acquired within one heartbeat cycle to obtain ultrasound signals for all spatial locations within one complete heartbeat cycle. The ultrasound host is also used to synchronize the resting state of the heart at various spatial locations, taking the resting state of the heart as the starting time and the relative excitation time of each spatial location as the start time of cardiac excitation at each spatial location within a heartbeat cycle, to obtain a three-dimensional excitation conduction sequence. The ultrasound host is specifically used to scan different target spatial locations, where the target spatial location is any one of the spatial locations; The ultrasonic signals of the nth ultrasonic echo beam and the (n+1)th ultrasonic echo beam traversing to the target spatial position are respectively acquired at the mth beam position. The excitation displacement of the ultrasonic signal at the mth beam position is obtained by cross-correlation calculation. The initial value of m is 1, and the value ranges from 1 to M, where M is the total number of beam positions scanned. Let n = n + 1, return to the step of traversing the N consecutive time intervals of the target spatial location until n = N - 1, to obtain the maximum excitation amplitude of the target spatial location and the start time of cardiac excitation relative to the resting state of the heart, where N is the total number of ultrasound echo beams received at the target spatial location.

2. The system according to claim 1, characterized in that, The ultrasound host is used to display the three-dimensional excitation conduction sequence in three-dimensional dynamic form, and at the same time, to display the maximum excitation amplitude at each spatial location in three-dimensional dynamic form, so as to obtain a three-dimensional cardiac excitation conduction sequence diagram and the distribution of the maximum amplitude.

3. The system according to claim 1, characterized in that, The ECG electrocardiogram signal acquisition system is also used to record the acquisition time of ultrasound signals at various spatial locations within one heartbeat cycle.

4. The system according to claim 1, characterized in that, The ICE catheter also includes a three-dimensional positioning sensor, which is fixed to the ICE probe. The three-dimensional positioning sensor is used to obtain the three-dimensional spatial position and imaging angle of the probe, thereby locating the position of the ultrasonic beam and the spatial position of abnormal transmission of excitation.

5. The system according to claim 1, characterized in that, The system can be used as an ICE imaging system for ultrasound imaging of the heart, obtaining B-mode images of the heart, and performing blood flow imaging; it can also be used as a non-contact mapping system for three-dimensional mapping of cardiac electrophysiology.

6. The system according to claim 1, characterized in that, The ICE probe is a single-element probe, a linear array ultrasonic probe, a phased linear array ultrasonic probe, a surface array probe, a ring array probe, or a mechanically rotating linear array probe; the probe material is PZT ceramic material, composite material, CMUT, or PMUT material.

7. The system according to claim 1, characterized in that, The ICE catheter has a communication connection with the ultrasound host, and the ultrasound host has a communication connection with the ECG electrocardiogram signal acquisition system.

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