Comparison of Focal Cryoablation vs. Radiofrequency Cardioneuroablation for Bradyarrhythmias

NCT07671898 | Recruiting

• 1 other identifier: CRI-281/2
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

Bradyarrhythmias are conditions where the heart beats too slowly, causing symptoms like dizziness, fainting, and fatigue. In some patients, these slow heart rhythms are caused by overactivity of the vagus nerve (the part of the nervous system that slows the heart down). Cardioneuroablation (CNA) is a catheter-based procedure that targets and reduces the effect of these overactive nerves on the heart. It is an alternative to permanent pacemaker implantation, especially for younger patients. Traditionally, CNA is performed using radiofrequency (RF) energy to create small burns in specific areas of the heart. This study investigates whether focal cryoablation (freezing technology using the Freezor™ Xtra catheter) is as safe and effective as standard RF ablation for CNA. This is a prospective, non-randomized study. Participants will receive either RF ablation (N=30) or cryoablation (N=30). The study will evaluate the recurrence of slow heart rhythms and fainting episodes, as well as any complications, over 12 months of follow-up.

Conditions

Bradycardia; Syncope, Vasovagal; Sick Sinus Syndrome; Atrioventricular Block

Keywords

Cardioneuroablation,; Cryoablation; Radiofrequency Ablation; Ganglionated Plexi; Parasympathetic Nervous System; Bradyarrhythmias; Functional Bradycardia; Vasovagal Syncope; Sick Sinus Syndrome; Atrioventricular Block

Outcome Measures

Primary Outcomes (1)

• Recurrence of Bradyarrhythmia or Syncope

  Documented recurrence of symptomatic bradyarrhythmia (sinus bradycardia \<40 bpm, pause \>3 sec, AV block) or syncope confirmed by ECG or Holter

  12 months

Secondary Outcomes (7)

• Pericardial Effusion or Hemopericardium

  Periprocedural (7 days)

• Inappropriate Sinus Tachycardia

  12 months

• Vascular Access Complications

  Periprocedural (7 days)

• Change in Minimum Heart Rate

  Baseline to 6 months

• Change in Maximum Heart Rate

  Baseline to 6 months

Study Arms (2)

CryoCNA

EXPERIMENTAL

Procedure: Focal Cryoablation

RF CNA

ACTIVE COMPARATOR

Procedure: Radiofrequency Catheter Ablation

Interventions

Focal Cryoablation PROCEDURE

Focal cryoablation of right atrial ganglionated plexi using Freezor™ Xtra 6mm catheter (Medtronic) at -75°C for 240 seconds per application. 3-5 applications per GP zone. Positioned by fluoroscopy and impedance-based tracking in EnSite™ X system.

CryoCNA

Radiofrequency Catheter Ablation PROCEDURE

Radiofrequency ablation of right atrial ganglionated plexi using TactiFlex™ SE catheter (Abbott) with power up to 45W, temperature 50°C, target AI 45, with irrigation. 3-5 applications per GP zone. Guided by EnSite™ X mapping system and spectral analysis (OTNF).

RF CNA

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Age 18 to 60 years;
• Symptomatic bradycardia (sinus bradycardia or bradycardia due to atrioventricular block, including transient);
• Severe asymptomatic sinus bradycardia (heart rate less than 30 beats per minute);
• Transient second- or third-degree atrioventricular block;
• Persistent second-degree atrioventricular block;
• Rhythm pauses greater than 6 seconds;
• Recurrent syncope or presyncope with documented association with bradycardia (without trauma);
• Positive response to atropine (heart rate increase ≥25% from baseline or \>90 beats per minute) OR positive response to exercise (heart rate increase ≥25% from baseline or \>90 beats per minute, OR conversion of second- or third-degree atrioventricular block to first-degree block or complete normalization of atrioventricular conduction during sinus rhythm);

You may not qualify if:

• Chronic antiarrhythmic drug therapy (ongoing);
• Presence of implanted pacemaker, cardiac resynchronization therapy device, or implantable cardioverter-defibrillator;
• Bradyarrhythmia secondary to medications;
• Bradyarrhythmia secondary to electrolyte imbalance (hyperkalemia);
• Bradyarrhythmia secondary to hypothyroidism;
• Bradyarrhythmia secondary to obstructive sleep apnea syndrome;
• Absence of response to pharmacological denervation (no heart rate increase after atropine administration up to maximum dose of 0.2 mg/kg);
• Clinically significant coronary artery disease;
• Post-myocardial infarction cardiosclerosis;
• Hemodynamically significant congenital heart disease (including surgically corrected);
• Stable ventricular tachycardia in the setting of bradycardia;
• History of stroke or transient ischemic attack;
• Prior open-heart surgery;
• Prior catheter-based coronary artery intervention or percutaneous coronary intervention;
• Pregnancy or breastfeeding; Age less than 18 years Age greater than 60 years

Sponsors & Collaborators

• Tomsk National Research Medical Center of the Russian Academy of Sciences: lead

Study Sites (1)

Cardiology Research Institute, Tomsk National Research Medical Center of the Russian Academy of Sciences

Tomsk, Tomsk Oblast, 634012, Russia

RECRUITING

MeSH Terms

Conditions

Bradycardia; Syncope, Vasovagal; Sick Sinus Syndrome; Atrioventricular Block

Interventions

Catheter Ablation

Condition Hierarchy (Ancestors)

Arrhythmias, Cardiac; Heart Diseases; Cardiovascular Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms; Orthostatic Intolerance; Primary Dysautonomias; Autonomic Nervous System Diseases; Nervous System Diseases; Syncope; Unconsciousness; Consciousness Disorders; Neurobehavioral Manifestations; Neurologic Manifestations; Signs and Symptoms; Arrhythmia, Sinus; Heart Block; Cardiac Conduction System Disease

Intervention Hierarchy (Ancestors)

Radiofrequency Ablation; Radiofrequency Therapy; Therapeutics; Ablation Techniques; Surgical Procedures, Operative

Central Study Contacts

Roman E Batalov, MD, PhD

CONTACT

+73822558401; romancer@rambler.ru

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: June 22, 2026
• First Posted: June 26, 2026
• Study Start: September 1, 2024
• Primary Completion (Estimated): December 25, 2027
• Study Completion (Estimated): December 25, 2028
• Last Updated: June 26, 2026

Record last verified: 2026-06

Data Sharing

• IPD Sharing: Will not share

Locations

RU (1)