Basic and Clinical Study of Cardiac Ganglion Catheter Ablation for the Treatment of Significant Bradycardia

Inclusion Criteria: 1. Age range: 18 - 65 years old 2. Have symptoms related to bradycardia (syncope, dizziness, blackout, palpitations, fatigue, listlessness, inability to concentrate and decreased activity endurance, etc.) 3. Meet one of the following conditions: ①Dynamic electrocardiogram shows an average heart rate of less than 50 beats per minute or there is a heart arrest lasting more than 3 seconds during the day; ②Transient second or third degree atrioventricular conduction block without hemodynamic disorders during the day 4. The atropine test showed that the sinus heart rate increased by ≥ 25%, or the heart rate was ≥ 90 beats per minute, or the atrioventricular conduction block was significantly improved to be no more than first-degree atrioventricular conduction block. Exclusion Criteria: 1. A history of severe trauma caused by bradycardia 2. Regular use of antiarrhythmic drugs within the past 3 months 3. Prior implantation of a cardiac pacemaker 4. Existing implantation of, or indication for implantation of, electronic devices with pacing function, such as cardiac contractility modulators (CCMs), implantable cardioverter-defibrillators (ICDs), or cardiac resynchronization therapy (CRT) devices 5. Bradycardia or atrioventricular block caused by medications or other reversible factors (e.g., hyperkalemia, hypothyroidism) 6. Bradycardia or atrioventricular block associated with obstructive sleep apnea syndrome (OSAS) 7. Coronary revascularization within the past 3 months, or unstable coronary heart disease despite standardized medical treatment or revascularization 8. Stroke or transient ischemic attack (TIA) within the past 3 months 9. A history of open-heart surgery 10. Severe congenital heart disease 11. Complicated with severe ventricular arrhythmia 12. Severe cardiac insufficiency with left ventricular ejection fraction (LVEF) ≤ 35% 13. Severe cardiomyopathy, such as hypertrophic obstructive cardiomyopathy (HOCM), dilated cardiomyopathy (DCM), or cardiac amyloidosis 14. Severe aortic or mitral valve stenosis 15. Pregnancy or lactation period 16. Expected survival time of less than 1 year 17. Refusal to sign the informed consent form 18. Other conditions deemed ineligible by the researchers