Multicenter Comparative Study on the Diagnostic Efficacy of "Ultra-high Sensitivity" Cardiomagnetic Detection and Myocardial Nucleoradiology Scanning for Early Diagnosis of Myocardial Ischemia.
Conditions: Myocardial Ischemia
Sponsor: Yang Jing

Chongqing Emergency Medical Center
The Fourth People,s Hospital of Chongqing
Chongqing University Central Hospital
Multicenter Comparative Study on the Diagnostic Efficacy of “Ultra-high
Sensitivity” Cardiomagnetic Detection and Myocardial Nucleoradiology
Scanning for Early Diagnosis of Myocardial Ischemia
Study Protocol
Proposal Version Number：V2.0
Date：March-4-2025
Research Team:Chongqing Emergency Medical Center
Hangzhou Institute of Extermely-weak Magnetic Field Major
National Science and Technology Infras tructure
Qilu Hospital of Shandong University

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1.Research background....................................................................................................1
2.Research purposes........................................................................................................4
3.Study design.................................................................................................................4
3.1General Design........................................................................................................4
3.2Subject selection.....................................................................................................4
3.3Evaluation method................................................................................................ 5
3.4Bias control measures............................................................................................. 5
4.Statistical Analysis......................................................................................................6
5.Study flow................................................................................................................... 7
6.Clinical monitoring..................................................................................................... 9
7.Data management.......................................................................................................9
8.Risk benefit analysis................................................................................................. 10
9.Quality assurance and quality control ....................................................................................10
10.Principle of confidentiality..................................................................................... 11
11.Time plan ................................................................................................................ 11
12.References...............................................................................................................11

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1.Background information
1.1 Disease background and epidemiology
Coronary atherosclerotic heart disease (CHD) is characterized by its high incidence and severe impact. With
the acceleration of the aging process, the incidence and mortality of CHD in China are continuously increasing,
making it one of the major chronic diseases affecting the health of the Chinese people. In recent years, with the rapid
development of evidence-based medicine and interventional cardiology, the clinical significance of coronary
microvascular disease (CMVD) has increasingly gained attention. Previous clinical studies have shown that in
patients with myocardial ischemic symptoms but with non-obstructive lesions on coronary angiography, the
incidence of CMVD is approximately 45% to 60%[1]. In 2020, the European Association of Percutaneous
Cardiovascular Interventions (EAPCI) and the ESC jointly released a consensus document on ischemia with non-
obstructive coronary artery (INOCA), proposing that CMVD and/or epicardial coronary vasospasm are the main
causes of INOCA.
Whether CHD patients choose conservative drug therapy or interventional treatment after coronary
angiography, or the treatment plan for CMVD patients, all are closely related to whether there is myocardial
ischemia. Furthermore, the degree of myocardial ischemia varies significantly among individual patients, leading to
different clinical treatment decisions. The current established method for detecting myocardial ischemia is emission
computed tomography (ECT), which utilizes a radiotracer labeled with thallium-201 or technetium-99m. By
recording the radioactivity in the myocardium during rest or stress conditions, it can identify segmental decreases in
myocardial perfusion, perfusion defects, or redistribution phenomena in both states, thereby diagnosing myocardial
ischemia. The advantage of this technology is its high diagnostic sensitivity and negative predictive value, but its
disadvantages include low spatial resolution and radiation exposure. The latter especially makes it difficult for
patients to undergo timely examinations, resulting in delays in the early diagnosis of myocardial ischemia. In
contrast, ultra-high sensitivity magnetic detection can non-invasively and without contact or radiation damage early
and rapidly detect the extremely weak magnetic fields of the heart, which is expected to achieve precise early
identification of myocardial ischemia, thus guiding patient treatment.
1.2 Research and development background
Magnetocardiography (MCG) is a non-invasive, risk-free, and contactless technology that characterizes the
local magnetic field signals generated by the electrical activity of the heart[2]. The magnetic signals from the heart
and the electrical signals from the heart are of the same origin. The ionic activity within myocardial cells forms
volume currents, and the curve representing the potential difference caused by these currents on the body surface
over time is known as the Electrocardiogram (ECG)[3]. The spatial magnetic field changes caused by volume
currents are referred to as magnetocardiograms[4]. Magnetocardiograms are constructed by recording the magnetic
signals of the heart using a multi-channel sensor array placed above the chest, thereby mapping the heart's magnetic
field. By analyzing these magnetic maps, abnormal electrical activities of the heart can be detected, including
myocardial ischemia, arrhythmias, and myocardial diseases[5]. Traditional ECG detection technology is affected by
various conductivities of human tissues and skin[6], whereas the magnetic signals used in magnetocardiograms can
pass through the body with almost no interference. Therefore, magnetocardiography theoretically offers more

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clinically useful information, with the advantages of being non-invasive, safe, and fast, enabling earlier and more
accurate diagnoses of potential heart diseases[7,8].
With the development of biomagnetic detection technology and the updating of detection equipment, the new
generation of Spin-exchange relaxation-free (SERF) atomic magnetometers achieves a high density of alkali metal
vapor by high temperatures, suppresses spin-exchange relaxation, and realizes a very high low-frequency magnetic
field sensitivity in weak magnetic fields. Recently, our country has successfully developed a heart magnetic
measurement device based on spin-exchange relaxation-free magnetic measurement technology. This device has
successfully completed 64-channel time-sharing heart magnetometry and 32-channel synchronous heart
magnetometry. It can dynamically display the changes in heart magnetic topography and current density maps,
reflecting the corresponding electrophysiological activities of the heart. The device has the capability to perform
heart magnetometry in a free environment for the human body, making clinical research on “ultra-high
sensitivity”magnetocardiogram possible.
MCG imaging equipment represents a high-end medical device in the quantum precision measurement era.
Utilizing ultra-weak magnetic field detection and high-performance magnetic shielding technologies, it captures
subtle changes in cardiac magnetic signals reflecting human heart function. This technology offers a novel approach
for the clinical diagnosis and assessment of cardiovascular diseases, demonstrating promising applications across the
medical field.This study is based on a “ultra-high sensitivity” cardiomagnetic detection device that captures spatial
magnetic field changes in ischemic myocardial cells, providing early warning, early diagnosis, and localization
detection for myocardial ischemia, thereby serving public health（Figure 1）.
Figure 1 Domestic “ultra-high sensitivity” cardiomagnetic detection device
1.3 Basic product information
The device consists of an array of magnetometer sensors, a high-performance magnetic shielding system, a
multifunctional bed, and a heart magnetic signal processing system. Featuring exceptional sensitivity for ultra-weak

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magnetic signal detection, it enables high-resolution monitoring of faint magnetic fields generated by the human
cardio-electrophysiological network. With advantages including contact-free operation, high precision, and rapid
testing capabilities, this system represents a truly functional diagnostic tool for cardiac assessment.
MCG signals and ECG signals share the same origin. The ionic activities in myocardial cells generate volume
currents. The curve of potential difference on the body surface changing with time caused by these currents is
called an ECG, while the spatial magnetic field changes formed by the volume currents are referred to as a MCG[1].
MCG devices are non-invasive and contactless systems designed to map the localized magnetic field signals
generated by cardiac electrical activity[2]. MCG systems construct magnetic field maps of the heart by recording
cardiac magnetic signals using multi-channel sensor arrays positioned above the chest [3]. Analysis of these MCG
maps enables the identification of abnormal cardiac electrical activities[4]. Traditionally, ECGs are affected by the
conductivity of human tissues and skin. In contrast, compared to electrocardiograms, cardiac magnetic signals can
pass through the human body almost undisturbed, providing more clinically useful functional information, thereby
allowing for a more advanced and accurate assessment of myocardial electrophysiological conditions[5, 6].
The core component of the heart magnetic detection device is the SERF atomic magnetometer, which uses a
novel alkali metal atom operating in the SERF state to achieve extremely weak magnetic measurements. It has
advantages such as non-cryogenic operation (traditional magnetometers require cooling with liquid helium),
miniaturization, and high spatial resolution.The basic principle is: using high temperature to achieve a higher density
of alkali metal vapor in the gas cell, suppressing spin-exchange relaxation, and using polarized detection light that is
perpendicular to the pump light entering the gas cell to measure the Larmor precession frequency of spin-polarized
atoms in a weak magnetic field, thus accurately reflecting the magnitude of the external magnetic field. The SERF
magnetometer has achieved high sensitivity to low-frequency magnetic fields in weak magnetic fields. The
magnetic field of the heart is only 10-7 times the intensity of the Earth's magnetic field signal, and the new generation
of SERF atomic magnetometers makes the study of “ultra-high sensitivity” cardiac magnetometry possible.
1.4 Scope of application and related information
Product Name: “Ultra-high Sensitivity” Cardiomagnetic Detection Device
Product Performance Structure and Composition: The heart magnetic detection device consists of a
magnetic shielding system, a magnetic field detection array, a movable examination bed, heart magnetic imaging
software, and a main control system.
Expected Use: To collect and record the magnetic signals of the human heart.
Target Population: Individuals requiring examination for heart diseases or health check-ups.
International studies on SQUID (Superconducting Quantum Interference Device)-based magnetocardiography
have preliminarily demonstrated MCG's diagnostic efficacy for conditions like myocardial ischemia [9-11]. However,
its clinical adoption faces significant constraints due to complex operational requirements (e.g., cryogenic
environments), high costs, intricate diagnostic modeling parameters, lack of standardized protocols, and limited
patient cohort sizes[1]. With the advent of domestically developed high-performance SERF-MCG systems, there is
an urgent need to conduct large-scale clinical validation studies assessing MCG's capability for myocardial ischemia

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detection. Such research is crucial for advancing China's premium medical equipment toward domestic and global
market penetration.
2.Research purposes
Primary Objective: To compare the consistency of “ultra-high sensitivity” cardiomagnetic detection with
resting and stress ECT (exercise stress and pharmacological stress) in diagnosing myocardial ischemia.
Secondary objective: To study the diagnostic efficacy (specificity and sensitivity) of “ultra-high sensitivity”
cardiomagnetic detection of myocardial ischemia using ECT as a reference, and to explore the value of
domestically produced "ultra-high sensitivity" cardiac magnet detection for myocardial ischemia.
3. Study design
3.1 General Design
This study is a prospective, multi-center comparative study. Patients with symptoms of myocardial ischemia
who are considered for the diagnosis of CHD or CMVD and are scheduled for ECT examination will be included.
Subjects will be randomly recruited, and a domestically manufactured “ultra-high sensitivity” cardiomagnetic
detection device will be used to collect cardiac magnetic images. The ECT examination will be completed within
one week. A consistency analysis will be conducted between the cardiac magnetic results and the ECT results to
evaluate the early diagnostic efficacy of cardiac magnetic detection for myocardial ischemia. Subgroup analyses will
also be performed based on resting and stress conditions.
3.2 Subject selection
Inclusion Criteria
1）Age ≥18 years;
2）Presence of myocardial ischemia-related symptoms (e.g., angina pectoris) with suspected CHD or CMVD,
scheduled for ECT examination;
3）Signed informed consent form.
Exclusion Criteria
1）Hemodynamic instability (systolic blood pressure <90 mmHg or requiring vasoactive drugs);
2）Cardiac arrhythmias, including ventricular tachycardia, ventricular fibrillation, severe sinus bradycardia and
sinus pauses, and second - degree or higher - degree atrioventricular block and other severe arrhythmias;
3）Aortic dissection aneurysm, severe aortic valve stenosis or insufficiency;
4）Elderly or frail patients with neuromuscular or osteoarticular diseases who cannot complete exercise stress
ECT;
5）Allergy to drugs used in pharmacologic stress ECT;
6）Patients with severe renal insufficiency with an estimated glomerular filtration rate (eGFR) < 30 ml/min or
those undergoing dialysis;
7）Patients with malignant tumors and a life - expectancy of less than1 year;
8）Pregnant or lactating women;

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9）Patients unable to undergo MCG examination due to inability to enter the chamber, metallic implant
interference, or other conditions deemed unsuitable by researchers.
3.3 evaluation method
3.3.1.Primary Evaluation Indicators
Evaluation Indicators: Diagnostic concordance between “ ultra-high sensitivity” magnetocardiography (MCG)
and rest/stress ECT (including exercise and pharmacological stress protocols) for detecting myocardial ischemia.
Criteria and Measurement Methods: Paired comparative design where all subjects undergo both ECT and MCG
examinations, with consistency analysis of diagnostic outcomes between modalities.
3.3.2 Secondary Evaluation Indicators
Evaluation Indicators:Using ECT as a control, to study the diagnostic efficacy (specificity and sensitivity) of
“ultra-high sensitivity” cardiomagnetic detection for myocardial ischemia, and to explore the value of domestic
“ultra-high sensitivity” cardiomagnetic detection for myocardial ischemia.
Criteria and Measurement Methods: Myocardial ischemia is defined according to the results of ECT detection.
Based on the degree of myocardial perfusion defects, patients are categorized into no myocardial ischemia, mild
myocardial ischemia, moderate myocardial ischemia, and severe myocardial ischemia, with the ischemic area
calculated. The performance evaluation differentiation indicators include sensitivity, specificity, area under the
receiver operating characteristic curve (Area under ROC curve, AUC), recall rate, and F1 score, among others.
3.4 Bias control measures
This study may have selection bias, information bias, and confounding bias.
Selection bias may specifically manifest as enrollment population bias, such as too few ECT-negative
individuals for myocardial ischemia or a higher mean age in the study cohort. The control measure is to strictly
adhere to inclusion and exclusion criteria to ensure the representativeness of the study population.
Information bias may arise from misunderstandings of variables, leading to biased values. For example, there
can be significant differences in responses when individuals have varying understandings of the same variable. The
control measure is to establish a unified and standardized definition for the variables. Additionally, the scientific
attitude of the participants is crucial. Through standardized training and strict requirements, we can minimize such
biases as much as possible. Anomalies in cardiac magnetic signals can cause parameter deviations, leading to
information bias, such as single-channel abnormalities, external magnetic wave interference, and metal interference
(Figure 2). Control measures include selecting a room with minimal external interference when locating the cardiac
magnetic room, confirming the absence of external interference before conducting a cardiac magnetic examination,
checking if the patient has any metal on them, and ensuring that individual probes are not damaged. Personnel
involved in the cardiac magnetic signal collection should strictly adhere to collection protocols and carry out regular
maintenance of the equipment.
Confounding bias may arise from risk factors such as diabetes mellitus and hypertension, as well as
electrophysiological alterations induced by anxiety, depression, or emotional stress, causing interference with MCG-

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based myocardial ischemia detection. Quality control will be implemented during statistical analysis through
matching, pseudo-randomization, and stratified analysis based on specific circumstances.
Figure 2 Preventing information bias caused by interference or
abnormality of magnetocardiographic signals
4. Statistical Analysis
4.1 Sample size estimation
In this project sample size calculation was performed to ensure the statistical reliability of the study. By
considering factors such as the expected effect size and significance level, an appropriate sample size was
determined. This ensures sufficient support for testing the study hypothesis, guarantees scientifically credible results,
enhances study reproducibility, and boosts data analysis robustness, thereby making the study conclusions more
convincing and reliable.
For testing the non - inferiority of cardiomagnetic evaluation of myocardial ischemia compared to ECT, the sample
size estimation used the method for comparing paired two - sample rates in a non - inferiority design and was
calculated as follows:
n=(Zα+Zβ)2×(p1(1−p1)+p2(1−p2))/(p1−p2−Δ)2
In the formula：
Zα is the critical value of the standard normal distribution;
Zβ is the critical value of the standard normal distribution corresponding to the power;

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�1 and �2 represent the positive rates of the control group and the intervention group, respectively;
Δ：non-inferiority margin;
α：significance level;
β：power of the test.
The preliminary experimental results indicated a 77% positive rate for cardiomagnetic detection and 71% for
ECT，with α=0.05 (one - sided), β=0.2 (power 80%), and Δ=0.05. We calculated the minimum sample size to be
196 cases, with a total sample size of 196 cases. Considering a dropout rate of 10%, the final determined sample size
was 218 cases.
4.2 Statistical methods
Unless otherwise stated, the following general principles will be used for statistical analysis of the study data.
For categorical variables, statistical descriptions will be provided as the number and percentage of participants
in each category. For continuous variables, the mean, standard deviation, median, Q1，Q3 and extremes will be
listed. Diagnostic efficiency will be evaluated using sensitivity, specificity, AUC, recall, and F1 score for
discrimination. Calibration will be assessed via calibration curves and the Hosmer-Lemeshow (H-L) test. Subgroup
analyses will be conducted for rest ECT and stress ECT groups to compare diagnostic efficiency and consistency.
The Pearson correlation coefficient will assess the linear relationship between cardiomagnetic scores and ECT
ischemic areas, with the correlation coefficient (r) and significance level (p value) reported. The Kappa coefficient
will evaluate the consistency of cardiomagnetic detection with rest and stress ECT in diagnosing myocardial
ischemia, with the consistency level reported.All statistical tests will use a significance level of 0.05.
5.study flow
The study is aimed at selecting and enrolling patients who come to the hospital with symptoms of myocardial
ischemia such as chest tightness and chest pain, suspected of having CHD or CMVD, and who are scheduled to
undergo ECT. For patients who have already undergone coronary CTA or CAG and are scheduled for ECT, after an
initial screening, a consent form will be signed, and inclusion/exclusion criteria will be re-verified. Patients
successfully enrolled will undergo cardiomagnetic detection. For patients with acute myocardial infarction,
cardiomagnetic detection will be performed once the condition allows and ECT will be completed within one week.
Outpatients and inpatients, except those with contraindications for burden ECT, are required to undergo both resting
and burden ECT. After completing the relevant examinations (Table 1, research flow chart), data required for the
study will be collected according to the Case Report Form (CRF) requirements.
project
screening
Before
magnetocardi
ography
Magnetocardi
ographic
testing
In-hospital
inspection and
observation
signed the informed
consent form[1]
√
demographic data
√

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Medical history, current
medical history[2]
√
Height, weight
√
Blood pressure[3]
√
ECG[4]
√
Coronary CTA or
angiography[5]
√
Magnetocardiography
√
Echocardiography[6]
√
ECT[7]
√
Table 1 research flow chart
[1] Written informed consent must be obtained from the subject or guardian before screening can begin。
[2] The current medical history needs to record the characteristics and duration of chest pain symptoms。
[3] Blood pressure was measured before magnetic examination to assess patient condition。
[4] ECG examination was performed within 5min before/after MCT examination, and ECG data were exported as
original electronic data。
[5] According to routine clinical diagnosis and treatment examinations, DICOM format is regularly exported and
submitted to the center for QFR/CTFFR calibration.。
[6] According to routine clinical diagnosis and treatment examinations, the study only records test results。
[7] The patient underwent cardiac magnetic examination within one week after the ECT scan。
ECT Imaging Protocol:
(1) Patient Preparation before Imaging:
①It is advisable to be fasting. Patients undergoing a load test in the late morning or afternoon may consume a
light diet; it is recommended that insulin-dependent diabetic patients schedule the load test in the morning.
②Discontinue the consumption of caffeine-containing beverages, tea, food, and medications for 24 hours
before the load test; discontinue the use of methylxanthine medications for 36 hours.
③Discontinue short-acting nitrates at least 2 hours before the load test and long-acting nitrates for at least 6
hours.
④Discontinue calcium channel blockers within 24 hours before the load test, andβ-blockers within 48 hours.
（2）Imaging Method
Key Points of Imaging Technology (taking the two-day or one-day gated stress/rest imaging method using
99mTc-labeled imaging agents as an example):
1. Imaging Agent: 99mTc-Methoxyisobutylnitrile (MIBI) or 99mTc-Tetrofosmin (TC).
2. Imaging Methods:

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99mTc-MIBI Stress-Rest Two-Day Imaging Method: Inject intravenously 740-925 MBq (20-25 mCi) at peak
stress, perform imaging 1.0-1.5 hours later, then inject 740-925 MBq (20-25 mCi) the next day and perform imaging
again 1.0-1.5 hours later.
99mTc-MIBI Exercise-Rest One-Day Imaging Method: Inject 296-222 MBq (8-9 mCi) at rest, perform rest
imaging 1.0-1.5 hours later, then perform exercise testing 1-4 hours later and reinject 814-925 MBq (22-25 mCi)
followed by imaging 1.0-1.5 hours later.
3. Precautions: After intravenous injection of the imaging agent, have a fatty meal 30 minutes later to reduce
interference from radioactive drugs in the liver and gallbladder on the images of the left ventricle's inferior wall.
4. Imaging Sequence: For the two-day method, rest imaging can be done before stress imaging or vice versa;
for the one-day method, it is recommended to perform rest imaging before stress imaging.
5. Stress Test: Commonly employs exercise stress (treadmill or bicycle) or pharmacological stress
(Regadenoson, Adenosine, ATP, or Dipyridamole). Detailed recommendations for the stress test should be provided,
including testing environment, related equipment, stress protocols, emergency equipment, drug preparation, and
emergency plans. Physicians responsible for the stress test should have received formal training in patient rescue or
be assisted by a cardiologist to monitor the subjects. If the patient can exercise and is expected to reach the stress
level, exercise testing is preferred; otherwise, pharmacological stress testing should be performed. For patients with
left bundle branch block, pre-excitation syndrome, or those who have undergone pacemaker implantation,
pharmacological stress testing should be the first choice. The basic principle is to meet the indicators of the stress test
as much as possible, complete the comparison analysis of the stress and rest gated MPI, and pay attention to analyze
positive indicator information provided by the stress test and its monitored ECG (such as ST segment changes,
arrhythmias, angina attacks, etc.).
6.clinical monitoring
To safeguard participants' rights and ensure the trial data is accurate, complete, and reliable and that the
implementation is in line with the study protocol, the center appoints monitors to visit the research unit regularly or
as per actual needs to carry out monitoring work.
Monitors' responsibilities include: （1）Pre - trial checks to confirm the trial - undertaking unit has proper
conditions, such as adequate and well - trained staff, well - functioning equipment, necessary examination facilities,
sufficient participants, and researchers familiar with the protocol.
（2）During the trial, monitoring researchers' protocol compliance, confirming informed consent from all
participants, and ensuring eligible participants are enrolled.
（3）Verifying the accuracy and completeness of data records and reports, and ensuring correct data entry in
case report forms that matches source data.
7. Data management
Before the first participant is enrolled, the data manager sets up eCRFs (Electronic case report form) and logic
verification procedures in the EDC (Electronic data capture system) system as per the protocol, completes user

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testing, and launches it. All EDC users must finish relevant training, have records filed, and then can access the
study’s eCRF. When using electronic signatures on eCRFs, users need to confirm and agree to the relevant
statement. Accounts are for individual use only, and passwords should be well - kept and changed regularly. If there
are personnel changes in the study team, access rights need to be revoked timely.
The EDC system's verification logic procedure checks the completeness and logic of entered data, and flags
potential issues. Investigators or data entry personnel can correct data or respond to queries for clarification and
confirmation. Monitors, quality control personnel, and data managers review eCRF data and may query
questionable data. Investigators should promptly respond to system - generated and personnel - issued queries,
which may be repeated until data issues are resolved. Before database lock, the study team must complete data
cleaning and hold a data review meeting to finalize the analysis population, with all decisions documented. After the
meeting, the team confirms the EDC database lock, making data unchangeable. Upon study completion, the EDC
system generates PDF eCRFs, saved on read - only discs by the center. Study materials are preserved and managed
per GCP, with essential documents kept for at least 10 years post - study.
8.Risk benefit analysis
The safety risks of the interventions in this study are low. Electrocardiograms (ECG), coronary angiography
(CAG), coronary CT angiography (CTA), and SPECT have been used clinically for many years, ensuring their
safety. The magnetic cardiogram examination is conducted in a weak magnetic field environment, is non-invasive,
and involves no radiation, which almost eliminates any additional risk. During the execution of the study,
researchers must provide clear explanations about informed consent and also adequately disclose the risks associated
with this study. Patients scheduled for CAG/CTA or SPECT may experience anxiety, and researchers should
possess ample clinical and research experience to ensure normal patient care and handle any emergencies effectively,
thereby ensuring the smooth implementation of the project.
9.Quality assurance and quality control
To ensure trial quality, before the official start of the study, the central unit and researchers should discuss and
formulate the clinical research plan together. It should be confirmed whether the relevant researchers participating in
the trial have received appropriate GCP training. According to GCP guidelines, necessary steps should be taken
during the design and implementation phases of the study to ensure that the data collected is accurate, consistent,
complete, and credible. All data in clinical trials should be verified and recorded in a timely manner to ensure data
reliability. The instruments and equipment used for various inspection items in clinical trials should meet strict
quality standards and ensure they are functioning properly. Researchers will input the information required by the
protocol into the eCRF, which will be verified by monitors for completeness and accuracy, and necessary
corrections and explanations will be made by the researchers based on actual circumstances. The research center will
establish quality management personnel to conduct necessary supervision of clinical trials. Monitors will
systematically check clinical research-related activities and documents to evaluate whether they are conducted in
accordance with the study protocol, investigator's brochure, and relevant regulations, and whether research data is
recorded in a timely, truthful, accurate, and complete manner.

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10.principle of confidentiality
The confidentiality of subject information will be strictly enforced by the researchers and participating research
personnel. The research protocol, documents, data, and all other information generated will be kept strictly
confidential. No relevant research or data information shall be disclosed to any unauthorized third party without the
prior written approval of the central unit. Authorized representatives of the central unit, ethics committees, and
regulatory authorities can inspect all documents and records that the researchers are required to maintain, including
but not limited to: medical records and subject records, and the research center shall allow access to these records.
The contact information of the subjects will be securely stored and used only internally during the research process.
At the end of the research, all records will continue to be stored securely for the duration specified by the local ethics
committee and regulations. The subject research data collected for statistical analysis and scientific reporting will be
uploaded and stored at the research center. The research data entry and research management systems used by
researchers at each clinical research center are confidential and password protected. At the end of the research, all
identifying information in the research database will be eliminated and archived at the research center.
The information contained in this research protocol is only provided to the project's researchers, the clinical
research management committee, and relevant institutions for review. Without the approval of the principal
investigator, it is strictly forbidden to disclose any information to third parties that are not related to this research.
11.Time plan
2025.06—2025.10
Research training and preparation, with sub-centers kicking off one by one.
2025.10—2026.10
Complete recruitment and preliminary data entry, quality control, and verification, and
conduct an initial analysis and evaluation.
2026.10—2026.12
Complete data tracing, cleaning, and database lock, analyze final results, and generate the
report.
12.References
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[5] Cohen D, Norman J C, Molokhia F, et al. Magnetocardiography of direct currents: S-T segment and
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