Pacemaker Implantation Versus Cardioneuroablation for Functional Atrioventricular Block

Inclusion Criteria: 1. Written informed consent to participate in the study 2. Age 18-75 3. Indication (at least one) of the European Society of Cardiology (ESC) for elective pacemaker implantation due to isolated (without sinus node dysfunction and bundle branch block) paroxysmal, persistent or reflex atrioventricular block: 1. Symptomatic first degree AVB (above 300 msec). Class IIaC 2. Symptomatic Mobitz type I second degree AVB. Class IIaC 3. AVB 2:1, even asymptomatic, but not during sleep. Class IIaC 4. Mobitz II type advanced 2nd degree AVB or complete block (3rd degree AVB). Class IC 5. Advanced AVB during AF regardless of symptoms, but not during sleep. Class IC 6. Reflex syncope in patients over 40 years of age with documented pauses within the AVB mechanism, symptomatic (\>3 sec) or asymptomatic \>6 sec. Class IC 7. Reflex syncope in patients over 40 years of age with documented pauses within AVB mechanism in the course of sick sinus syndrome (CSS). Class IC 8. Reflex syncope in patients over 40 years of age with documented pauses within AVB mechanism during tilt test. Class IC Exclusion Criteria: 1. Implanted pacemaker/ICD/CRT 2. Sinus node dysfunction with indication for pacemaker implantation 3. Planned ablation of the atrioventricular junction 4. Severe prolonged bradycardia in advanced AVB requiring intravenous drugs and temporary pacing 5. Status post cardiac surgery 6. Acute myocardial infarction and heart failure (not related to bradycardia) 7. Status post percutaneous valvular intervention or ablation 8. Acute infection or any other accompanying disease which is contraindication to percutaneous procedures and/or implantation of a pacemaker 9. Pregnancy, nursing or planned pregnancy within 12 months 10. Decompensated chronic diseases (endocrine disorders, electrolyte disorders, etc.) 11. Advanced cardiomyopathies with indication for ICD implantation in primary or secondary prevention of sudden cardiac death (SCD) 12. Advanced ventricular arrhythmias with indication for ICD implantation in primary or secondary prevention of SCD 13. Persistent right or left bundle branch block 14. Musculoskeletal diseases with separate indications for pacemaker implantation 15. Contraindications to the procedures used in the study 16. The presence of a mental illness or limitation of cognitive functions that prevent independent participation in the study, including the use of telemedicine services 17. Any abnormality found that is considered by the Principal Investigator a contraindication to participate in the stidy due to data interpretation or safety issue