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Heterogeneous atrial denervation creates substrate for sustained atrial fibrillation
1Krannert Institute of Cardiology, Department of Medicine, Indiana University School of Medicine, Indianapolis, IN, USA. jolgin@iupui.edu
Circulation
|December 8, 1998
Summary
Heterogeneous sympathetic denervation using phenol in dogs created conditions for sustained atrial fibrillation (AF). This targeted nerve disruption altered electrophysiological properties, facilitating AF maintenance.
Area of Science:
- Cardiovascular Electrophysiology
- Autonomic Nervous System
- Atrial Fibrillation Pathophysiology
Background:
- Heterogeneous electrophysiological properties, influenced by autonomic innervation, are crucial for maintaining atrial fibrillation (AF).
- Autonomic dysfunction, particularly sympathetic innervation, plays a role in AF development and persistence.
Purpose of the Study:
- To investigate if heterogeneous sympathetic denervation using phenol could induce a state conducive to sustained AF.
- To explore the electrophysiological effects of targeted sympathetic denervation on atrial refractoriness and AF cycle length.
Main Methods:
- 15 dogs underwent atrial epicardial phenol application, while 11 received a sham procedure.
- AF inducibility, effective refractory period (ERP), and AF cycle lengths were assessed post-procedure.
- Positron Emission Tomography (PET) imaging with sympathetic ([11C]hydroxyephedrine, HED) and parasympathetic (5-[11C]methoxybenzovesamicol, MOBV) tracers evaluated nerve integrity.
Main Results:
- 14 of 15 phenol-treated dogs developed sustained AF, compared to none in the sham group.
- Phenol application significantly shortened ERP and increased dispersion of refractoriness and AF cycle length.
- PET imaging revealed HED uptake defects at phenol application sites, indicating sympathetic denervation, with no MOBV uptake defects.
Conclusions:
- Heterogeneous sympathetic atrial denervation with phenol effectively facilitates sustained AF.
- Targeted disruption of sympathetic innervation alters atrial electrophysiology, promoting AF maintenance.
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