Abstract 15692: Voltage Mapping in Atrial Fibrillation vs Sinus Rhythm: Results From the Mavs Study

Background: Left atrial (LA) scar can be identified with bipolar voltage mapping during sinus rhythm (SR). It is not clear whether the same voltage criteria can be applied during atrial fibrillation (AF). Objective: Aim of this study was to compare voltage maps performed in the same patient both in AF and SR. Methods: Voltage mapping was performed using a 10-pole circular mapping catheter in patients with non-paroxysmal AF undergoing first time RF ablation. For descriptive purposes, the LA was divided in 6 regions: septum, posterior wall (PW), inferior wall (IW), lateral wall, anterior wall, and roof. The threshold for low voltage was <0.5 mV (with a color range setting 0.2-0.5 mV). Mild “scar” was defined as an area low voltage 5-20%, moderate 20-35% and severe as >35%. Results: 16 patients (62% persistent AF, 38% longstanding persistent AF) were included in the study. The map density was comparable during AF and SR (mean points per map 551 vs 547, paired t test P = NS). 2 patients displayed normal voltage during both AF and SR. 14 patients showed areas of low voltage during AF, which were still present during SR in 8. All patients with mild “scarring” during AF (n = 4), showed normal voltage during SR. Of the 7 patients with moderate “scarring”, 2 patients showed normal voltage during SR, while in the remaining 5 “scarring” was only mild during SR. 3 patients showed extensive “scarring” during AF, which was only moderate during SR. During AF, areas of low voltage were more commonly observed in the PW (12/14) followed by the IW (6/14) and antero-septum (4/14); while in SR, in the antero-septum (4/8), PW (3/8) and IW (3/8). Interestingly, in all patients both the PW/IW and (less dramatically) the antero-septum showed more “scarring” during AF as compared to SR. Conclusion: Areas of low voltage are more severe and diffuse during AF when compared to SR. When areas of low voltage are detected during AF, they are more commonly seen in the PW, IW and antero-septal areas.

Download Full-text

Low-Voltage Zones as the Atrial Fibrillation Substrates: Relationship With Initiation, Perpetuation, and Termination

Frontiers in Cardiovascular Medicine ◽

10.3389/fcvm.2021.705510 ◽

2021 ◽

Vol 8 ◽

Author(s):

Zheng Liu ◽

Yu Xia ◽

Changyan Guo ◽

Xiaofeng Li ◽

Pihua Fang ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Distribution Pattern ◽

Left Atrium ◽

Surface Area ◽

Low Voltage ◽

Posterior Wall ◽

Anterior Wall ◽

Voltage Mapping ◽

Significant Difference

Background: Low-voltage zones (LVZs) were usually targeted for ablation in atrial fibrillation (AF). However, its relationship with AF initiation, perpetuation, and termination remains to be studied. This study aimed to explore such relationships.Methods: A total of 126 consecutive AF patients were enrolled, including 71 patients for AF induction protocol and 55 patients for AF termination protocol. Inducible and sustainable AF were defined as induced AF lasting over 30 and 300 s, respectively. Terminable AF was defined as those that could be terminated into sinus rhythm within 1 h after ibutilide administration. Voltage mapping was performed in sinus rhythm for all patients. LVZ was quantified as the percentage of the LVZ area (LVZ%) to the left atrium surface area.Results: The rates of inducible, sustainable, and terminable AF were 29.6, 18.3, and 38.2%, respectively. Inducible AF patients had no significant difference in overall LVZ% compared with uninducible AF patients (10.2 ± 11.8 vs. 8.5 ± 12.6, p = 0.606), while sustainable and interminable AF patients had larger overall LVZ% than unsustainable (16.2 ± 11.5 vs. 0.5 ± 0.7, p < 0.001) and terminable AF patients (44.6 ± 26.4 vs. 26.3 ± 22.3, p < 0.05), respectively. The segmental LVZ distribution pattern was diverse in the different stages of AF. Segmental LVZ% difference was initially observed in the anterior wall for patients with inducible AF, and the septum was further affected in those with sustainable AF, and the roof, posterior wall, and floor were finally affected in those with interminable AF.Conclusions: The associations between LVZ with AF initiation, perpetuation, and termination were different depending on its size and distribution.

Download Full-text

Spatial and quantitative assessment of the correlation between sinus rhythm and atrial fibrillation voltage mapping to identify low voltage substrate in persistent atrial fibrillation

EP Europace ◽

10.1093/europace/euab116.163 ◽

2021 ◽

Vol 23 (Supplement_3) ◽

Author(s):

D Nairn ◽

C Nagel ◽

B Mueller-Edenborn ◽

H Lehrmann ◽

A Jadidi ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Left Atrial ◽

Low Voltage ◽

Persistent Atrial Fibrillation ◽

Posterior Wall ◽

Shape Modelling ◽

National Budget ◽

Spatial Concordance ◽

Public Grant

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.

Download Full-text

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.

Download Full-text

P1021Low incidence of atrial tachycardia following ablation of low voltage areas in sinus rhythm for persistent atrial fibrillation

EP Europace ◽

10.1093/europace/euaa162.026 ◽

2020 ◽

Vol 22 (Supplement_1) ◽

Author(s):

A Lepillier ◽

X Copie ◽

W Escande ◽

M Niro ◽

O Paziaud ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Atrial Tachycardia ◽

Low Voltage ◽

Pulmonary Veins ◽

Left Atrial Volume ◽

Persistent Atrial Fibrillation ◽

Anterior Wall ◽

Rf Ablation ◽

Efficient Strategy

Abstract . Background: Dedicated ablation strategies for persistent atrial fibrillation (AF) have shown a limited success rate with frequent atrial tachycardia (AT) occurrence. Recent studies suggest that atrial arrhythmogenic sites are related to tissular heterogeneities and increased fibrosis can be identified as reduced bipolar voltage areas. . Purpose: Targeting low voltage areas (LVA) in addition to PVI may represent an efficient strategy for the ablation of persistent AF, and may limit the risk of AT recurrence. . Methods: We prospectively included consecutive patients with symptomatic persistent AF. The ablation strategy consisted of the following steps: circumferential pulmonary vein isolation (CPVI), Sinus rhythm restoration by electrical cardioversion, voltage map performed in sinus rhythm. Complementary RFA was guided by low voltage areas (0.2-0.4 mV). Success was defined as freedom from AF/ atrial flutter or atrial arrhythmia at 12 months or more. . Results: 101 patients (mean age: 62.5 +/- 10.4 years, men 73%) were included with persistent AF or long standing AF (7%). Procedure time was: 154 ± 25 min and fluoroscopy time: 184 ± 90 sec. Time of RFA was 44.7 +/- 12 min. Mean LA volume was 182 +/- 38 mL. LVA were found in 50 patients (49.5%). The distribution of these areas was: 30 anterior wall 29.7%), 21 septum (20.7%), 19 roof (18.8%), 5 inferior (4.9%), 11 left appendage (10.8%), 6 posterior (5.9%), 3 mitral isthmus (3%). RF ablation was realized for all LVA and homogenisation was attempt. After a single procedure at a mean FU of 12 months, 72.3% of patients were free of symptomatic AF. 27 patients had recurrence of atrial AF: 7 permanent, 15 persistent and 5 paroxysmal AF. Predictive factors of recurrence of AF were: long standing persistent AF, large left atrial volume (> 205 mL), shorts AF cycle length (< 168 ms) and reduce LEVF (< 45%). Atrial tachycardia occurred in 5 patients (4,9%). Mechanisms of AT were: typical cavo-tricuspid flutter in one patient, peri-mitral flutter in 2 patients, and atrial focal tachycardia (close to pulmonary veins) in 2 patients. . Conclusion: These results suggest that PVI with complementary RF ablation guided on low voltage areas is an efficient strategy for symptomatic persistent AF, and reduce the recurrence of AT following this ablation strategy.

Download Full-text

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

Download Full-text

TGFβ Is Specifically Upregulated on Circulating CD14++ CD16+ and CD14+ CD16++ Monocytes in Patients with Atrial Fibrillation and Severe Atrial Fibrosis

Cellular Physiology and Biochemistry ◽

10.1159/000492873 ◽

2018 ◽

Vol 49 (1) ◽

pp. 226-234 ◽

Cited By ~ 4

Author(s):

David Heinzmann ◽

Stefan Fuß ◽

Saskia v. Ungern-Sternberg ◽

Jürgen Schreieck ◽

Meinrad Gawaz ◽

...

Keyword(s):

Atrial Fibrillation ◽

Catheter Ablation ◽

Sinus Rhythm ◽

Low Voltage ◽

Strong Increase ◽

Atrial Remodeling ◽

Myocardial Remodeling ◽

Monocyte Subsets ◽

Atrial Fibrosis ◽

Voltage Mapping

Background/Aims: Fibrotic remodeling of the atria plays a key role in the pathogenesis of atrial fibrillation (AF). As little is known about the contribution of circulating monocytes in atrial remodeling and the pathophysiology of AF, we investigated profibrotic factors in different subsets of circulating monocytes obtained from patients with atrial fibrillation undergoing catheter ablation. Methods: A 3D high density voltage mapping was performed in sinus rhythm to evaluate the extent of low-voltage areas (LVAs) in the atria of 71 patients with persistent AF. Low-voltage was defined as signals of < 0.5mV during sinus rhythm. Prior to ablation, blood was drawn and monocytes were analyzed by FACS. Based on the expression of CD14 and CD16, three subgroups including CD14++ CD16- (‘classical’), CD14++ CD16+ (‘intermediate’), and CD14+ CD16++ (‘non-classical’) were analyzed for the expression of TGFb, CD147, and MMP-9, representing pivotal profibrotic pathways in myocardial remodeling. Results: Expression of TGFb was increased in CD14+ monocytes of patients with extensive LVAs compared to patients with a low extend of LVAs. While CD14++ CD16- monocytes showed no difference, CD14++ CD16+ and CD14+ CD16++ monocytes showed a strong increase of TGFb abundance. Although CD147 and MMP-9 are strongly associated with myocardial fibrosis, we found no difference in expression between the two groups in any monocyte subsets. Conclusion: TGFb is specifically upregulated on CD14++ CD16+ and CD14+ CD16++ monocytes in patients with extensive LVAs undergoing catheter ablation.

Download Full-text

Relationship between left atrial strain and left atrial bipolar voltage in patients undergoing catheter ablation for atrial fibrillation

European Heart Journal ◽

10.1093/ehjci/ehaa946.0387 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

Y Takahashi ◽

T Kitai ◽

T Watanabe ◽

T Fujita

Keyword(s):

Atrial Fibrillation ◽

Left Atrial ◽

Speckle Tracking ◽

Longitudinal Strain ◽

Low Voltage ◽

Pulmonary Veins ◽

Global Longitudinal Strain ◽

Inferior Wall ◽

Bipolar Voltage ◽

Global Mean

Abstract Background Low-voltage zone (LVZ) in the left atrium (LA) seems to represent fibrosis. LA longitudinal strain assessed by speckle tracking method is known to correlate with the extent of fibrosis in patients with mitral valve disease. Purpose We sought to identify the relationship between LA longitudinal strain and LA bipolar voltage in patients with atrial fibrillation (AF). We tested the hypothesis that LA strain can predict LA bipolar voltage. Methods A total of 96 consecutive patients undergoing initial AF ablation were analyzed. All patients underwent transthoracic echocardiography including 2D speckle tracking measurement on the day before ablation during sinus rhythm (SR group, N=54) or during AF (AF group, N=42). LA longitudinal strain was measured at basal, mid, and roof level of septal, lateral, anterior, and inferior wall in apical 4- and 2-chamber view. Global longitudinal strain (GLS) was defined as an average value of the 12 segments. LA voltage map was created using EnSite system, and global mean voltage was defined as a mean of bipolar voltage of the whole LA excluding pulmonary veins and left atrial appendage. LVZ was defined as less than 1.0 mV. Results There was a significantly positive correlation between GLS and global mean voltage (r=0.708, p<0.001). Multivariate regression analysis showed that GLS and age were independent predictors of global mean voltage. There was a significant negative correlation between global mean voltage and LVZ areas. Conclusions There was a strong correlation between LA longitudinal strain and LA mean voltage. GLS can independently predict LA mean voltage, subsequently LVZ areas in patients with AF. Funding Acknowledgement Type of funding source: None

Download Full-text

P3731The improvement in left atrial strain among patients undergoing percutaneous left atrial appendage closure

European Heart Journal ◽

10.1093/eurheartj/ehz745.0585 ◽

2019 ◽

Vol 40 (Supplement_1) ◽

Author(s):

S Ijuin ◽

A Hamadanchi ◽

F Haertel ◽

L Baez ◽

C Schulze ◽

...

Keyword(s):

Atrial Fibrillation ◽

Sinus Rhythm ◽

Transesophageal Echocardiography ◽

Left Atrial ◽

Left Atrial Appendage ◽

Lateral Wall ◽

Bleeding Risk ◽

Atrial Appendage ◽

Left Atrial Appendage Closure ◽

Left Atrial Strain

Abstract Background Percutaneous left atrial appendage closure (LAAC) is being established as an alternative option for atrial fibrillation (AF) patients with high bleeding risk. Few studies reported the influence of percutaneous LAAC on left atrial (LA) performance, but most of the studies demonstrated no remarkable changes in their parameters after the procedure. Method The study included 95 patients (age: 75±6.7 years, 67% male) whom underwent percutaneous LAAC in a single center between September 2012 and November 2018. LA strain was evaluated at three different time intervals by transesophageal echocardiography (baseline, 45 days and 180 days after procedure). All data were analyzed using a dedicated. 70 patients had atrial fibrillation whereas 25 were in sinus rhythm. Analysis was performed for peak atrial longitudinal strain (PALS) and peak atrial contraction strain (PACS) from segment of lateral wall in mid-esophageal 4 chamber view. The validity of lateral wall left atrial analysis was recently shown by our group. PACS was obtained in patients with sinus rhythm during exams. Results Compared to baseline, PALS was significantly increased after 45 days (12.4±8.4% vs 16.0±10.7%, p=0.001) and remained stable after 180 days (13.8±9.0% vs 17.0±12.4%, p=0.098). Even in only patients with atrial fibrillation during exams, it was increased (10.8±7.7% vs 13.4±7.1%, p=0.012 and 8.5±5.1% vs 13.9±8.1%, p=0.014). Similarly, compared with the baseline, PACS was significantly increased after 45 days and 180 days (5.8±3.9% vs 10.6±7.6%, p=0.001 and 4.5±2.6% vs 7.9±3.1%, p=0.036). The Changes in PALS and PACS Conclusion Our study has demonstrated for the first time the improvement in LA strain following LAAC within 45 days of implantation by transesophageal echocardiography and these values were maintained at least for 6 months. Further appraisal is warranted for confirmation of these preliminary findings.

Download Full-text