Driver Domains in Persistent Atrial Fibrillation
Background—A specific non-invasive signal processing was applied to identify drivers in distinct categories of persistent atrial fibrillation (PsAF).
Methods and Results—In 103 consecutive PsAF patients, accurate biatrial geometry relative to an array of 252-body-surface-electrodes was obtained from non-contrast CT-scan. The reconstructed unipolar AF-electrograms acquired bedside from multiple windows (duration:9±1 seconds) were signal-processed to identify the drivers (focal or re-entrant activity) and their cumulative density-map. The driver domains were catheter ablated using AF termination as procedural endpoint in comparison with stepwise-ablation control group. The maps showed incessantly changing beat-to-beat wavefronts and varying spatio-temporal behaviour of driver activities. Re-entries were not sustained (median 2.6 rotations lasting 449±89 ms), meandered substantially but recurred repetitively in the same region. Totally, 4720 drivers were identified in 103 patients: 3802(80.5%) re-entries and 918(19.5%) focal breakthroughs; most of them co-localized. Of these, 69% re-entries and 71% foci were in left atrium. Driver ablation alone terminated 75% and 15% of persistent and long-lasting AF, respectively. The number of targeted driver regions increased with the duration of continuous AF: 2 in patients presenting in sinus rhythm, 3 in AF 1-3 months, 4 in AF 4-6 months and 6 in AF lasting longer. Termination rate sharply declined after 6 months. Mean RF delivery to AF termination was 28±17 min vs. 65±33 min in control group (p<0.0001). At 12 months, 85% patients with AF-termination were free from AF, similar to control population(87%,);p-NS.
Conclusions—Persistent AF in early months is maintained predominantly by drivers clustered in few regions, most of them being unstable reentries.
- persistent atrial fibrillation
- driver domain
- non-invasive mapping
- phase mapping
- rotor activity
- noninvasive imaging
- atrial fibrillation arrhythmia
- phase analysis
- Received August 1, 2013.
- Revision received May 28, 2014.
- Accepted June 6, 2014.