Determination of MCG Reference Intervals in Healthy Individuals

Inclusion Criteria: 1. Age 18 years or older. 2. Those with no hospitalization for any reason in the 6 months prior to the study. 3. Those who are not currently taking any prescribed medications. 4. Those with no history of cardiovascular diseases, including coronary artery disease, structural heart disease, arrhythmia, heart failure, stroke, pulmonary embolism, aortic coarctation, or peripheral arterial disease. 5. Those with no risk factors for cardiovascular diseases, including hypertension, diabetes mellitus, hyperlipidemia. 6. Those with no history of smoking (previous non-smoking or smoking cessation \>6 months). 7. Those with no excessive alcohol consumption (average daily alcohol consumption \<3 drinks, 1 drink = beer 355mL / white wine 44mL / red wine 118mL). 8. Signed informed consent. Exclusion Criteria: 1. Those with body mass index \>28kg/m2 or \<18kg/m2. 2. Those with resting heart rate \<50 beats/min, or \>110 beats/min. 3. Those with resting systolic blood pressure ≥ 140 mmHg, and/or diastolic blood pressure ≥ 90 mmHg. 4. Those with fasting blood glucose ≥7 mmol/L, and/or random blood glucose ≥11.1 mmol/L. 5. Those with total cholesterol ≥6.2 mmol/L or low-density lipoprotein cholesterol ≥4.1 mmol/L. 6. Those with abnormal electrocardiograms, such as arrhythmias, ST-T changes, and pathologic electrical axis deflections. 7. Those with cardiac ultrasonographic pathologic findings, such as left ventricular hypertrophy, left ventricular dilatation, abnormal ventricular wall motion, and valvular regurgitation or stenosis of more than mild degree. 8. Those with respiratory diseases, kidney diseases, liver diseases, endocrine diseases, anaemia or other blood diseases, connective tissue diseases, malignant tumors and other diseases. 9. Professional athletes, pregnant or lactating women, psychological or psychiatric disorders such as depression. 10. Those who are unable to perform magnetocardiography due to claustrophobia, etc., or those who are unable to cooperate with the corresponding examinations required by the study for various reasons.