Dataset Information

Voltage during atrial fibrillation is superior to voltage during sinus rhythm in localizing areas of delayed enhancement on magnetic resonance imaging: An assessment of the posterior left atrium in patients with persistent atrial fibrillation.

ABSTRACT:

Background

Bipolar electrogram voltage during sinus rhythm (V_SR) has been used as a surrogate for atrial fibrosis in guiding catheter ablation of persistent atrial fibrillation (AF), but the fixed rate and wavefront characteristics present during sinus rhythm may not accurately reflect underlying functional vulnerabilities responsible for AF maintenance.

Objective

The purpose of this study was determine whether, given adequate temporal sampling, the spatial distribution of mean AF voltage (V_mAF) better correlates with delayed-enhancement magnetic resonance imaging (MRI-DE)-detected atrial fibrosis than V_SR.

Methods

AF was mapped (8 seconds) during index ablation for persistent AF (20 patients) using a 20-pole catheter (660 ± 28 points/map). After cardioversion, V_SR was mapped (557 ± 326 points/map). Electroanatomic and MRI-DE maps were co-registered in 14 patients.

Results

The time course of V_mAF was assessed from 1-40 AF cycles (?8 seconds) at 1113 locations. V_mAF stabilized with sampling >4 seconds (mean voltage error 0.05 mV). Paired point analysis of V_mAF from segments acquired 30 seconds apart (3667 sites; 15 patients) showed strong correlation (r = 0.95; P <.001). Delayed enhancement (DE) was assessed across the posterior left atrial (LA) wall, occupying 33% ± 13%. V_mAF distributions were (median [IQR]) 0.21 [0.14-0.35] mV in DE vs 0.52 [0.34-0.77] mV in non-DE regions. V_SR distributions were 1.34 [0.65-2.48] mV in DE vs 2.37 [1.27-3.97] mV in non-DE. V_mAF threshold of 0.35 mV yielded sensitivity of 75% and specificity of 79% in detecting MRI-DE compared with 63% and 67%, respectively, for V_SR (1.8-mV threshold)_. CONCLUSION: The correlation between low-voltage and posterior LA MRI-DE is significantly improved when acquired during AF vs sinus rhythm. With adequate sampling, mean AF voltage is a reproducible marker reflecting the functional response to the underlying persistent AF substrate.

SUBMITTER: Qureshi NA

PROVIDER: S-EPMC6722483 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature

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Publications

Voltage during atrial fibrillation is superior to voltage during sinus rhythm in localizing areas of delayed enhancement on magnetic resonance imaging: An assessment of the posterior left atrium in patients with persistent atrial fibrillation.

Qureshi Norman A NA Kim Steven J SJ Cantwell Chris D CD Afonso Valtino X VX Bai Wenjia W Ali Rheeda L RL Shun-Shin Matt J MJ Malcolme-Lawes Louisa C LC Luther Vishal V Leong Kevin M W KMW Lim Elaine E Wright Ian I Nagy Szabi S Hayat Sajad S Ng Fu Siong FS Wing Michael Koa MK Linton Nick W F NWF Lefroy David C DC Whinnett Zachary I ZI Davies D Wyn DW Kanagaratnam Prapa P Peters Nicholas S NS Lim Phang Boon PB

Heart rhythm 20190603 9

<h4>Background</h4>Bipolar electrogram voltage during sinus rhythm (V<sub>SR</sub>) has been used as a surrogate for atrial fibrosis in guiding catheter ablation of persistent atrial fibrillation (AF), but the fixed rate and wavefront characteristics present during sinus rhythm may not accurately reflect underlying functional vulnerabilities responsible for AF maintenance.<h4>Objective</h4>The purpose of this study was determine whether, given adequate temporal sampling, the spatial distribution ...[more]

PMID: 31170484

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Dataset Information

Voltage during atrial fibrillation is superior to voltage during sinus rhythm in localizing areas of delayed enhancement on magnetic resonance imaging: An assessment of the posterior left atrium in patients with persistent atrial fibrillation.

Background

Objective

Methods

Results

Publications

Voltage during atrial fibrillation is superior to voltage during sinus rhythm in localizing areas of delayed enhancement on magnetic resonance imaging: An assessment of the posterior left atrium in patients with persistent atrial fibrillation.

Similar Datasets

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