Author + information
- Minki Hwang,
- Byounghyun Lim,
- Jun-Seop Song,
- Young-Seon Lee,
- Eun Bo Shim and
- Hui-Nam Pak
Background: Although it is known that autonomic nervous system (ANS) plays a significant role in atrial fibrillation (AF), its effects on the cardiac wave dynamics of AF are not fully understood. In this in silico study, we modeled the ANS in the left atrium (LA), and examined the effects of ANS on the cardiac wave dynamics of AF.
Methods: Ionic currents in the human atrial action potential model of Courtemanche et al. were adjusted and incorporated into a single cell and 3D realistic LA model. The morphology of the GP and nerves was modeled based on the “Octopus hypothesis”. A model of acetylcholine (ACh)-activated potassium current was used to examine the effect of ACh. Complex fractionated atrial electrogram (CFAE) cycle length was calculated for the models integrated by 10 patients’ LA geometry.
Results: 1. Single cell model exhibited a late Phase 3 Early after-depolarization (EAD)-like depolarization immediately after rapid pacing with ACh stimulation (ACh-stim, 0.03 μM). 2. Spontaneous pulmonary vein (PV) tachycardia was observed at left atrial (LA)-PV junction after ACh-stim on GPs and isoproterenol stimulation (5 × ICa-L) in 3D model. 3. During AF state, PV triggers near GP area were shown under the ionic current conditions of sustained AF. 4. GP stimulation reduced complex fractionated atrial electrogram (CFAE) cycle length (CL; 137±18ms to 127±14ms, p<0.001) and maintenance duration of phase singularities (PS), (66±100ms to 60±88ms, p<0.001), and increased co-localized GP area with CFAE-CL≤120ms area (2.9% to 25.1%., p<0.001).
Conclusions: Simultaneous GP and ICa-L stimulation induced triggered activity from LA-PV junction and PV tachycardia, changing wave-dynamics of AF maintenance mechanism in single cell and 3D in silico octopus-GP model of the LA.
Poster Hall, Hall C
Saturday, March 18, 2017, 3:45 p.m.-4:30 p.m.
Session Title: Arrhythmias and Clinical EP: Basic 4
Abstract Category: 4. Arrhythmias and Clinical EP: Basic
Presentation Number: 1238-114
- 2017 American College of Cardiology Foundation