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

Beijing Anzhen Hospital188 enrolled

Overview

This study adopts a strategy combining basic research with clinical investigation to systematically explore the therapeutic value of cardioneuroablation in the treatment of vagally-mediated bradycardia. The study design fully considers the complexity of the scientific question and the feasibility of clinical translation. Through rigorous experimental design and standardized operational procedures, the reliability and reproducibility of the study results are ensured.

In recent years, cardiac ganglionated plexus (GP) ablation has emerged as a novel minimally invasive electrophysiological intervention. By targeting and ablating overactive GPs, this technique aims to suppress aberrant vagal signaling and alleviate symptoms of bradycardia. It offers distinct advantages, including a mechanism-targeted approach and the avoidance of permanent device implantation. Previous studies have demonstrated the feasibility and clinical potential of this technique in patients with vasovagal syncope, particularly the cardioinhibitory type. Therefore, developing such a "device-free" interventional therapy addresses a pressing clinical need and holds significant medical importance. Results from preliminary small-scale clinical studies suggest that GP ablation can significantly reduce syncope recurrence, improve quality of life, and increase resting heart rate. However, higher-level evidence regarding the efficacy and safety of cardiac GP ablation for the treatment of symptomatic bradycardia is still lacking. Consequently, this study combines basic and clinical research to address the unresolved questions regarding cardioneuroablation, aiming to fill this evidence gap and establish an evidence-based therapeutic strategy for patients with significant, vagally-mediated bradycardia.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

TRIPLE

Enrollment

Interventions

CardioneuroablationPROCEDURE

The procedure is performed under local anesthesia with conventional sedation using 1-3 mg of midazolam. The decision to administer additional sedation is assessed based on the patient's level of consciousness. The femoral vein is punctured, and a sheath is placed. Through this femoral venous sheath, catheters are advanced via the right atrium to position electrodes in the coronary sinus and the right ventricle. Under the guidance of intracardiac echocardiography and fluoroscopy (X-ray), a transseptal puncture is performed. The ablation catheter is then introduced into the left atrium through the transseptal sheath to sequentially perform catheter ablation of the left atrial and, selectively, the right atrial ganglionated plexi.

Sham ControlPROCEDURE

Throughout the procedure, the patient continuously wears over-ear headphones playing music and an eye mask. The surgery is performed under local anesthesia with conventional sedation using 1-3 mg of midazolam. The decision to administer additional sedation is assessed based on the patient's level of consciousness. Preoperative preparation, femoral vein puncture, placement of electrode catheters, and the electrophysiological study protocol are the same as in the intervention group; however, no transseptal puncture, ganglion mapping, or catheter ablation is performed.

Eligibility

Sex: ALLMin age: 18 YearsMax age: 65 Years

Medical Language ↔ Plain English

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

Outcomes

Primary Outcomes

Postoperative Average Heart Rate by 24-Hour Ambulatory Electrocardiogram

Average heart rate measured using 24-hour ambulatory electrocardiogram monitoring.

Time frame: Baseline, 1, 3, 6 and 12 months after ablation.

Secondary Outcomes

Heart Rate Variability

Autonomic Nervous Function Testing

Time frame: Baseline, 12 months after ablation.

Quality of Life Assessed by the Short Form-36 Health Survey (SF-36)

The Short Form-36 Health Survey (SF-36) is a validated questionnaire measuring health-related quality of life. Scores range from 0 to 100, with higher scores indicating better quality of life.

Time frame: Baseline, 12 months after ablation.

PR Interval by 24-Hour Ambulatory Electrocardiogram

PR interval measured using 24-hour ambulatory electrocardiogram monitoring.

Time frame: Baseline, 1, 3, 6, and 12 months after ablation.