Optimal cutoff value of bipolar low‐voltage in electroanatomic voltage mapping during atrial fibrillation rhythm

Abstract

Background Electroanatomic voltage mapping (EAVM) of the left atrium (LA) with multielectrodes is usually acquired during sinus rhythm (SR), and the feasibility of EAVM during atrial fibrillation (AF) rhythm is unclear. Methods We performed EAVM of LA during both SR and AF rhythm in 44 patients undergoing catheter ablation for AF and validated the optimal cutoff value of low‐voltage area (LVA) during AF rhythm for detecting LVA defined as bipolar voltages ≤0.5 mV during SR. Results In each session, mean 829 and 552 points were acquired by multielectrodes during SR and AF rhythm, respectively. Mean proportion of LVA was 4.9% among LA surface area of 276.2 cm2. Differences of LVA proportions between SR and AF rhythm were 5.8% (P < 0.001), 4.2% (P < 0.001), 2.7% (P < 0.001), 1.2% (P = 0.01), and –0.5% (P = 0.17) at the cutoff value of 0.4, 0.35, 0.3, 0.25, and 0.2 mV during AF rhythm, respectively. There was a good correlation between LVA proportions during SR and AF rhythm with cutoff value of 0.2 mV (R = 0.88, P < 0.001) and 37 patients (84.1%) had the discrepancy of LVA proportions within 3%. Furthermore, there was no significant difference between LVA proportions at each segment of LA. The discrepancy was relatively large in patients with large LA dimension and LVA during SR. Conclusion EAVM during AF rhythm was feasible and the optimal cutoff value of LVA was 0.2 mV for detecting LVA ≤ 0.5 mV during SR. However, the evidence is restricted to patients with relatively small LVA.

Instability of rotational activation as atrial fibrillation drivers: Assessment by ExTRa Mapping system

“…The clinical outcomes were compared with those in the historical controls who underwent catheter ablation for persistent AF with minimum additional ablation only for induced and sustained AF (21.9%). The details of ablation procedure for these historical controls were previously reported as the minimum substrate ablation 8 . Statistical analyses were performed using JMP 10 (SAS Institute Inc, Cary, NC) software.…”

“…The details of ablation procedure for these historical controls were previously reported as the minimum substrate ablation. 8 Statistical analyses were performed using JMP 10 (SAS Institute Inc, Cary, NC) software.…”

Characterization of persistent atrial fibrillation with non‐contact charge density mapping and relationship to voltage

“…Femoral venous access was used for double trans‐septal puncture, followed by heparinization to ACT >350 s. The baseline charge density map (pre‐PVI) was acquired for 30 s during AF with AcQMap, followed by a high density (>3000 points) contact map of the left atrium (LA) during AF using a multipolar catheter, either Advisor FL SE or Advisor HD Grid SE (Abbott Medical). A threshold of 0.2 mV (in AF) was used to define LVA as this has been shown to correlate with the conventional definition of 0.5 mV in sinus rhythm and with the presence of a scar on MRI 14,20 . Pulmonary vein isolation (PVI) was then performed either by de novo wide area circumferential ablation ( n = 6), or for redo procedures ( n = 10) at regions of vein reconnection with contact force guidance (TactiCath SE; Abbott Medical).…”

Using Machine Learning to Characterize Atrial Fibrotic Substrate from Intracardiac Signals using a Hybrid in silico and in vivo Dataset

“…Catheter ablation is a first line therapy for patients with persistent AF 3 . Substrate ablation strategies guided by a voltage map derived from the amplitude of intracardiac electrograms define areas based on a cut-off value (frequently < 0.5 mV during sinus rhythm) as pathological tissue and target them for ablation [4][5][6] . Several clinical studies have shown a correlation of fibrosis identified through late gadolinium enhancement magnetic resonance imaging (LGE-MRI) with reduced local signal amplitude ("voltage") in atrial electrograms 7,8 .…”