Abstract 13259: Electrophysiologic Mapping Identifies Stable Organized Tachyarrhythmias ('Rotors') in Both Atria during Spontaneous Atrial Fibrillation with Systolic Heart Failure

Introduction: Stable organized atrial tachyarrhythmias (ATs) /"rotors" that maintain AF have been identified in patients (pts) with paroxysmal atrial fibrillation (PAF) & persistent AF (PRAF) with no or minimal heart disease. Hypothesis: Biatrial ATs occur in AF pts with systolic heart failure (HF). Methods: We performed simultaneous contact catheter mapping of the RA & LA using 3 D non-contact mapping ) in 83 refractory AF pts during spontaneous AF episodes.Spontaneous atrial premature beats (APBs) & triggered ATs were analyzed. We also compared regional distribution of ATs & activation patterns in pts with & without HF. Results: 24 HF pts, mean age of 62±9 years, 75% male with mean left ventricular ejection fraction (LVEF) 45.5±9% and mean left atrial (LA) size 4.35±0.8 cm were mapped. They had 42 APBs that triggered 26 distinct organized stable ATs/"rotors". Each pt had 1 to 4 RA or LA regions showing triggering APBs (mean 1.75/pt) initiating AT. APBs arose predominantly from the RA or LA septum (45%) & superior LA/PV (24%) regions (Fig 1a). A biatrial distribution of the stable ATs/"rotors" occcurred in HF pts (Fig 1b) with few focal ATs. Compared to pts without HF (n=59), HF pts (n=24) trended to have more PRAF (83% vs 66%, p=0.18). 78 organized stable ATs/"rotors" were compared for regional distribution in PRAF pts with HF (n=16) & without HF (n=32). Stable ATs with focal LA/PV origin were uncommon in both groups (7% vs. 15%). LA ATs/"rotors" were similar (26% vs. 17%; p=0.58) as were typical RA flutter and atypical RA ATs/"rotors" in both groups (Fig 1c). Conclusions: 1. A majority of APBs initiating AF in HF pts originated from the septal and superior LA/PV regions. 2. While triggers are still frequently present with the LA/PV origin in HF pts, stable ATs/"rotors" had biatrial distribution & a lesser frequency of focal LA/PV ATs. 3. This spectrum of ATs/"rotors" was similar to PRAF pts without HF, potentially supporting similar ablative interventions in both pt groups.