Predicting Left Atrial Low-Voltage Areas During Sinus Rhythm on the Basis of Low Voltage During Atrial Fibrillation

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Deutsche Forschungsgemeinschaft (DFG) through DO637/22-3 Ministerium für Wissenschaft, Forschung und Kunst Baden-Württemberg through the Research Seed Capital (RiSC) program. Introduction Presence of left atrial (LA) fibrotic low voltage substrate (LVS) is associated with high risk for arrhythmia recurrences in patients undergoing pulmonary vein isolation (PVI) for atrial fibrillation (AF). PVI and additional ablation of LVS - as identified by mapping in sinus rhythm (SR) or AF - has been reported to improve SR maintenance rates, despite differences of the extent and distribution of LA-LVS in SR versus AF. Aims To study the relationship between SR and AF voltage maps, we sought to identify the optimal AF voltage threshold providing the highest concordance in the extent and distribution of LVS when comparing voltage maps in SR vs. AF. Methods Using the statistical shape modelling software Scalismo, the voltage information from the SR and AF maps (acquired prior to PVI) from 28 patients (66 ± 7 years, 46% male, 82% persistent AF) was projected onto a representative LA-geometry. Sensitivity and specificity of LVS identification were calculated for varying thresholds during AF and the correlation between the SR (threshold 0.5mV) and AF maps was assessed and areas of agreeing LVS classification (SR & AF) were identified for each patient. The data of all 28 patients were combined to a spatial histogram of agreement between SR and AF low voltage maps. Results The correlation between SR and AF maps was high across all patients, with agreement at 60-95% of all mapped sites (Figure A: each red triangle represents one patient and the respective agreement of LVS classification and substrate extent). The optimal AF threshold - to identify LA-LVS <0.5 mV in SR - was 0.29 mV (Q1-3: 0.20-0.37 mV) and was independent of the underlying extent of LVS during SR (Figure A: each blue asterisk represents one patient and the corresponding AF threshold and substrate extent). Agreement between LVS in AF vs. SR was high across most (>90) patients on the anterior LA, lateral LA and the left atrial appendage. Lower agreement (60% of patients) was observed in the posterior wall (Figure B). Conclusions SR and AF voltage maps reveal high spatial concordance in low voltage substrate at the anterior LA, lateral LA and LA appendage, however significant discordances in LVS are found in 40% of patients at the posterior LA. Further studies on an extended patient cohort should assess if regional voltage-thresholds would result in an improved substrate concordance between AF and SR substrate maps. Abstract Figure.

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Clinical Outcomes of low-voltage area-guided left atrial linear ablation for non-paroxysmal atrial fibrillation patients

PLoS ONE ◽

10.1371/journal.pone.0260834 ◽

2021 ◽

Vol 16 (12) ◽

pp. e0260834

Author(s):

Hao-Tien Liu ◽

Chia-Hung Yang ◽

Hui-Ling Lee ◽

Po-Cheng Chang ◽

Hung-Ta Wo ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Paroxysmal Atrial Fibrillation ◽

Left Atrial ◽

Low Voltage ◽

Reverse Remodeling ◽

Voltage Mapping ◽

Linear Ablation

Background The therapeutic effect of low-voltage area (LVA)-guided left atrial (LA) linear ablation for non-paroxysmal atrial fibrillation (non-PAF) is uncertain. We aimed to investigate the efficacy of LA linear ablation based on the preexisting LVA and its effects on LA reverse remodeling in non-PAF patients. Methods We retrospectively evaluated 145 consecutive patients who underwent radiofrequency catheter ablation for drug-refractory non-PAF. CARTO-guided bipolar voltage mapping was performed in atrial fibrillation (AF). LVA was defined as sites with voltage ≤ 0.5 mV. If circumferential pulmonary vein isolation couldn’t convert AF into sinus rhythm, additional LA linear ablation was performed preferentially at sites within LVA. Results After a mean follow-up duration of 48 ± 33 months, 29 of 145 patients had drugs-refractory AF/LA tachycardia recurrence. Low LA emptying fraction, large LA size and high extent of LVA were associated with AF recurrence. There were 136 patients undergoing LA linear ablation. The rate of linear block at the mitral isthmus was significantly higher via LVA-guided than non-LVA-guided linear ablation. Patients undergoing LVA-guided linear ablation had larger LA size and higher extent of LVA, but the long-term AF/LA tachycardia-free survival rate was higher than the non-LVA-guided group. The LA reverse remodeling effects by resuming sinus rhythm were noted even in patients with a diseased left atrium undergoing extensive LA linear ablation. Conclusions LVA-guided linear ablation through targeting the arrhythmogenic LVA and reducing LA mass provides a better clinical outcome than non-LVA guided linear ablation, and outweighs the harmful effects of iatrogenic scaring in non-PAF patients.

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10 Automated high density left atrial voltage mapping of low voltage areas in atrial fibrillation differs from sinus rhythm

10.1136/heartjnl-2021-ics.10 ◽

2021 ◽

Author(s):

J Mannion ◽

SJ Lennon ◽

J Keaney ◽

J Galvin ◽

J O’Brien ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Left Atrial ◽

Low Voltage ◽

High Density ◽

Voltage Mapping

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P2646P-wave duration in sinus rhythm correlates to extent of left atrial low-voltage and predicts outcome of pulmonary vein isolation in persistent atrial fibrillation

European Heart Journal ◽

10.1093/eurheartj/ehx502.p2646 ◽

2017 ◽

Vol 38 (suppl_1) ◽

Author(s):

B. Mueller-Edenborn ◽

J. Chen ◽

H. Lehrmann ◽

C. Keyl ◽

Y. El-Omri ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Pulmonary Vein ◽

Pulmonary Vein Isolation ◽

Left Atrial ◽

Low Voltage ◽

Persistent Atrial Fibrillation ◽

Wave Duration

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High incidence of left atrial dysfunction and low voltage zone in patients requiring multiple atrial fibrillation ablation

European Heart Journal ◽

10.1093/ehjci/ehaa946.0425 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

T Oka ◽

I Yoshimoto ◽

Y Koyama ◽

K Tanaka ◽

Y Hirao ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Recurrence Rate ◽

Left Atrial ◽

Low Voltage ◽

Peak Voltage ◽

Af Ablation ◽

Recurrent Atrial Fibrillation ◽

Linear Ablation ◽

Left Atrial Dysfunction

Abstract Background While multiple catheter ablation for recurrent atrial fibrillation (AF) is effective for the maintenance of sinus rhythm, some of patients have ablation-refractory AF. Left atrial (LA) dysfunction and the presence of low voltage zone (LVZ) are associated with recurrence after AF ablation. The association between recurrence and LA dysfunction/ LVZ among patients undergoing multiple AF ablation remains unclear. Purpose We aimed to compare (i)LA function, (ii)the prevalence of LVZ among patients undergoing first, second and third or more AF ablation procedures. Further, we investigated whether LA dysfunction and LVZ are associated with recurrence after multiple procedures. Methods We retrospectively analyzed 460 patients undergoing AF ablation procedures including first, second and third or more sessions from January 2017 to October 2019 in our institute. Before each session, 256-slice MDCT was performed under sinus rhythm to measure pre-ablation LA emptying fraction (LAEF) as the representative of LA function. At the end of each session, we checked the presence of LVZ, which was defined as regions where bipolar peak-to-peak voltage was <0.5mV. All patients underwent pulmonary vein isolation (PVI). If necessary, additional ablation (e.g. linear ablation, non-PV foci ablation and LVZ ablation) was performed. Results Out of 460 sessions, 295 were first (follow-up years: 1.5 [0.8, 2.0]), 134 were second (1.0 [0.5, 1.8]), and 31 were third or more sessions (1.2 [0.7, 2.0]). As the number of sessions increased, the recurrence rate was increased (19% vs. 31% vs. 61%, first vs. second vs. ≥third, P<0.0001), LAEF decreased (39.7±10.5% vs. 32.6±10.1% vs. 25.3±11.8%, P<0.0001) and the incidence of LVZ increased (18% vs. 34% vs. 68%, P<0.0001) (Figure 1). In patients with recurrence (N=104) after multiple ablation (second or more sessions), LAEF was lower and the prevalence of LVZ was higher than those without recurrence (N=61) (LAEF: 27.3±10.3% vs. 33.5±10.5%, with vs. without, P=0.0003; LVZ: 57% vs. 31%, P=0.0014). Conclusions As the number of sessions increased, the recurrence rate was increased. The prevalence of LA dysfunction and LVZ was high in patients requiring multiple ablation procedure. LA dysfunction and LVZ possibly reflect arrhytmogenic substrate causing recurrence of ablation-refractory AF. We should carefully consider repeated AF ablation in patients with severe LA dysfunction and extensive LVZ. Figure 1 Funding Acknowledgement Type of funding source: None

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