scholarly journals Association of left atrial strain by cardiovascular magnetic resonance with recurrence of atrial fibrillation following catheter ablation

2022 ◽  
Vol 24 (1) ◽  
Author(s):  
Mina M. Benjamin ◽  
Naeem Moulki ◽  
Aneeq Waqar ◽  
Harish Ravipati ◽  
Nancy Schoenecker ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Cardiovascular Magnetic Resonance ◽  
Catheter Ablation ◽  
Magnetic Resonance ◽  
Ejection Fraction ◽  
Left Atrial ◽  
Right Atrial ◽  
Volume Index ◽  
Computer Assisted ◽  
Af Recurrence

Abstract Background Atrial fibrillation (AF) is a progressive condition, which is characterized by inflammation/fibrosis of left atrial (LA) wall, an increase in the LA size/volumes, and decrease in LA function. We sought to investigate the relationship of anatomical and functional parameters obtained by cardiovascular magnetic resonance (CMR), with AF recurrence in paroxysmal AF (pAF) patients after catheter ablation. Methods We studied 80 consecutive pAF patients referred for ablation, between January 2014 and December 2019, who underwent pre- and post-ablation CMR while in sinus rhythm. LA volumes were measured using the area–length method and included maximum, minimum, and pre-atrial-contraction volumes. CMR-derived LA reservoir strain (ℇR), conduit strain (ℇCD), and contractile strain (ℇCT) were measured by computer assisted manual planimetry. We used a multivariate logistical regression to estimate the independent predictors of AF recurrence after ablation. Results Mean age was 58.6 ± 9.4 years, 75% men, mean CHA2DS2-VASc score was 1.7, 36% had prior cardioversion and 51% were taking antiarrhythmic drugs. Patients were followed for a median of 4 years (Q1–Q3 = 2.5–6.2 years). Of the 80 patients, 21 (26.3%) patients had AF recurrence after ablation. There were no significant differences between AF recurrence vs. no recurrence groups in age, gender, CHA2DS2-VASc score, or baseline comorbidities. At baseline, patients with AF recurrence compared to without recurrence had lower LV end systolic volume index (32 ± 7 vs 37 ± 11 mL/m2; p = 0.045) and lower ℇCT (7.1 ± 4.6 vs 9.1 ± 3.7; p = 0.05). Post-ablation, patients with AF recurrence had higher LA minimum volume (68 ± 32 vs 55 ± 23; p = 0.05), right atrial volume index (62 ± 20 vs 52 ± 19 mL/m2; p = 0.04) and lower LA active ejection fraction (24 ± 8 vs 29 ± 11; p = 0.05), LA total ejection fraction (39 ± 14 vs 46 ± 12; p = 0.02), LA expansion index (73.6 ± 37.5 vs 94.7 ± 37.1; p = 0.03) and ℇCT (6.2 ± 2.9 vs 7.3 ± 1.7; p = 0.04). Adjusting for clinical variables in the multivariate logistic regression model, post-ablation minimum LA volume (OR 1.09; CI 1.02–1.16), LA expansion index (OR 0.98; CI 0.96–0.99), and baseline ℇR (OR 0.92; CI 0.85–0.99) were independently associated with AF recurrence. Conclusion Significant changes in LA volumes and strain parameters occur after AF ablation. CMR derived baseline ℇR, post-ablation minimum LAV, and expansion index are independently associated with AF recurrence.

Abstract 15257: Epicardial and Peri-atrial Fat Attenuation Predict Recurrence in Patients Undergoing Repeat Catheter Ablation for Refractory Atrial Fibrillation

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Mark S Brahier ◽  
Fengwei Zou ◽  
Frank Migliarese ◽  
Milos Tomovic ◽  
Alexandra Taylor ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Logistic Regression ◽  
Adipose Tissue ◽  
Catheter Ablation ◽  
Left Atrial ◽  
Left Atrial Volume ◽  
Epicardial Fat ◽  
Volume Index ◽  
Atrial Volume ◽  
Af Recurrence

Background: Identifying factors predictive of atrial fibrillation (AF) recurrence after catheter ablation (CA) can improve patient selection. It has been hypothesized that inflammatory paracrine signaling by metabolically active adipose tissue induces pathologic changes in surrounding cardiovascular tissue. In fact, fat attenuation on CT has been previously associated with AF recurrence after de novo CA. The purpose of this study was to investigate the predictive qualities of epicardial and peri-atrial adipose tissue in a population undergoing repeat CA. We hypothesized that higher epicardial and left peri-atrial fat attenuation would predict recurrence as markers of increased localized inflammation. Methods: The study population consisted of 84 patients with symptomatic, drug and ablation-refractory AF undergoing repeat CA. All patients had a pre-ablation, contrast-enhanced cardiac CT, which was analyzed for mean fat attenuation in Hounsfield units (HU) and left atrial volume using the post-processing program 3D Slicer. Patients were followed for recurrence of atrial tachyarrhythmias after a 3-month blanking period. We performed logistic regression to adjust for age, sex, BMI, hypertension, smoking history, diabetes, obstructive sleep apnea, and left atrial volume index. Results: Repeat CA patients with recurrence (n=52) had a higher epicardial fat attenuation (-84.8 ±5.6 vs -88.1 ±5.2 HU; p=0.009) and peri-atrial fat attenuation (-81.0 ±4.7 vs -83.2 ±4.3 HU; p=0.036) than those without recurrence (n=32) at a mean follow-up period of 26 ±18 months. Logistic regression analysis showed that epicardial fat attenuation (OR 1.21; p=0.005) and peri-atrial fat attenuation (OR 1.27; p=0.007) are predictive of AF recurrence independent of traditional risk factors. Conclusions: Epicardial and left peri-atrial adipose attenuation are predictive of recurrence in patients undergoing repeat CA for AF.

scholarly journals Treatment-Related Changes in Left Atrial Structure in Atrial Fibrillation: Findings from the CABANA Imaging Substudy

2021 ◽  
Author(s):  
Maryam E. Rettmann ◽  
David R. Holmes III ◽  
Kristi H. Monahan ◽  
Jerome F. Breen ◽  
Tristram D. Bahnson ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Drug Therapy ◽  
Catheter Ablation ◽  
Clinical Outcomes ◽  
Primary Endpoint ◽  
Left Atrial ◽  
Volume Index ◽  
The Relationship ◽  
Af Recurrence

Background - The Catheter Ablation versus Antiarrhythmic Drug Therapy for Atrial Fibrillation (CABANA) trial was a randomized, prospective trial of left atrial catheter ablation versus drug therapy for treatment of atrial fibrillation (AF). As part of CABANA, a prospective imaging sub-study was conducted. The main objectives were to describe the patterns of changes in the dimensions of the left atrium (LA) and pulmonary veins (PVs), and the relationship between these changes with treatment assignment and clinical outcomes. Methods - CT or MRI was acquired at baseline and follow-up in 121 ablation (median follow-up 101 days) and 85 drug patients (median follow-up 97 days). Left atrial volume index (LAVI), mean PV ostial diameter (MPV) , and ostial diameters of each PV separately were computed. We examined the relationship between the change from baseline to follow-up with subsequent clinical outcomes (composite of death, disabling stroke, serious bleeding, or cardiac arrest [CABANA primary endpoint], total mortality or cardiovascular hospitalization, first AF recurrence after the 90 day blanking period, first AF/atrial flutter/ atrial tachycardia after the 90 day blanking period) using Cox proportional-hazards models. Results - The median (25 th , 75 th ) change from baseline for LAVI was -7.8 mL/m 2 (-16.4, 0.2), ablation arm and -3.5 mL/m 2 (-11.4, 2.6), drug therapy arm. The LAVI decreased in 52.9% of ablation patients versus 40.0% of drug therapy patients. Change for MPV was -2.7 mm (-4.2, -1.3) in the ablation arm versus -0.1 mm (-1.5, 0.8) in the drug therapy arm. Changes in LA and PV dimensions had no consistent relationship with the risk of developing the study primary endpoint. Reductions in LAVI, and in MPV diameter were associated with decreased risk of AF recurrence. Conclusions - Ablation patients demonstrated more frequent and larger atrial structural changes compared with drug patients. These changes suggest a critical relationship between structural features and AF generation.

scholarly journals Impact of Left Atrial Geometric Remodeling on Late Atrial Fibrillation Recurrence After Catheter Ablation

2021 ◽  
Author(s):  
Fuqian Guo ◽  
Caiying Li ◽  
Lan Yang ◽  
Chen Chen ◽  
Yicheng Chen ◽  
...  
Keyword(s):  
Risk Factors ◽  
Atrial Fibrillation ◽  
Regression Analysis ◽  
Catheter Ablation ◽  
Left Atrial ◽  
Volume Index ◽  
Multivariable Logistic Regression Analysis ◽  
Significant Difference ◽  
The Impact ◽  
Af Recurrence

Abstract Purpose: To quantitatively investigate the impact of left atrial (LA) geometric remodeling on atrial fibrillation (AF) recurrence after catheter ablation (CA).Methods: A retrospective analysis of 105 patients with AF who underwent coronary computed tomographic angiography before CA. Risk factors for AF recurrence were identified by multivariable logistic regression analysis and used to create a nomogram.Results: After at least 12 months of follow-up, 30 patients (29%) developed recurrent AF. Patients with recurrence had a higher LA volume, LA sphericity, and a lower LA ejection fraction (LAEF) (P < 0.05). There was no significant difference in asymmetry index between the two groups (P = 0.121). Multivariable regression analysis showed that LA minimal volume index (LAVImin) (OR: 1.280, 95% CI: 1.027–1.594, P = 0.028), LA sphericity (OR: 1.268, 95% CI: 1.071–1.500, P = 0.006) and CHA2DS2-VASc score (OR: 1.326, 95% CI: 1.016–1.732, P=0.038) were independent predictors of AF recurrence. The combined model of the LA sphericity to the LAVImin substantially increased the predictive power for AF recurrence (area under the curve [AUC] = 0.736, 95% CI: 0.627–0.844, P < 0.001), with a sensitivity of 80% and a specificity of 61%. A nomogram was generated based on the contribution weights of the risk factors; the AUC was 0.769 (95% CI: 0.666–0.872) and had good internal validity.Conclusion: The CHA2DS2-VASc score, LA sphericity, and LAVImin were significant and independent predictors of AF recurrence after CA. Furthermore, the nomogram had a better predictive capacity for AF recurrence.

scholarly journals Incremental value of left atrial booster and reservoir strain in predicting atrial fibrillation in patients with hypertrophic cardiomyopathy: a cardiovascular magnetic resonance study

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Betty Raman ◽  
Robert W. Smillie ◽  
Masliza Mahmod ◽  
Kenneth Chan ◽  
Rina Ariga ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Cardiovascular Magnetic Resonance ◽  
Hypertrophic Cardiomyopathy ◽  
Magnetic Resonance ◽  
Ejection Fraction ◽  
Left Atrial ◽  
Cardiovascular Magnetic Resonance Study ◽  
Control Subjects ◽  
Strain Components ◽  
New Onset

Abstract Background Left atrial (LA) size and function are known predictors of new onset atrial fibrillation (AF) in hypertrophic cardiomyopathy (HCM) patients. Components of LA deformation including reservoir, conduit, and booster function provide additional information on atrial mechanics. Whether or not LA deformation can augment our ability to predict the risk of new onset AF in HCM patients beyond standard measurements is unknown. Methods We assessed LA size, function, and deformation on cardiovascular magnetic resonance (CMR) in 238 genotyped HCM patients and compared this with twenty age, sex, blood pressure and body mass index matched control subjects. We further evaluated the determinants of new onset AF in HCM patients. Results Compared to control subjects, HCM patients had higher LA antero-posterior diameter, lower LA ejection fraction and lower LA reservoir (19.9 [17.1, 22.2], 21.6 [19.9, 22.9], P = 0.047) and conduit strain (10.6 ± 4.4, 13.7 ± 3.3, P = 0.002). LA booster strain did not differ between healthy controls and HCM patients, but HCM patients who developed new onset AF (n = 33) had lower booster strain (7.6 ± 3.3, 9.5 ± 3.0, P = 0.001) than those that did not (n = 205). In separate multivariate models, age, LA ejection fraction, and LA booster and reservoir strain were each independent determinants of AF. Age ≥ 55 years was the strongest determinant (HR 6.62, 95% CI 2.79–15.70), followed by LA booster strain ≤ 8% (HR 3.69, 95% CI 1.81–7.52) and LA reservoir strain ≤ 18% (HR 2.56, 95% CI 1.24–5.27). Conventional markers of HCM phenotypic severity, age and sudden death risk factors were associated with LA strain components. Conclusions LA strain components are impaired in HCM and, together with age, independently predicted the risk of new onset AF. Increasing age and phenotypic severity were associated with LA strain abnormalities. Our findings suggest that the routine assessment of LA strain components and consideration of age could augment LA size in predicting risk of AF, and potentially guide prophylactic anticoagulation use in HCM.

scholarly journals Left Atrial Appendage Remodeling after Atrial Fibrillation Ablation

2022 ◽  
Author(s):  
Yichi Zhang ◽  
Abdel Hadi El Hajjar ◽  
Chao Huang ◽  
Aneesh Dhore-Patil ◽  
Mario Mekhael ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Catheter Ablation ◽  
Ejection Fraction ◽  
Left Atrial ◽  
Left Atrial Appendage ◽  
Left Ventricular ◽  
Wilcoxon Test ◽  
Atrial Appendage ◽  
Volume Index ◽  
Af Ablation

Introduction: Larger left atrial appendage (LAA) ostium area and greater left atrial (LA) volume have been associated with an increased risk of ischemic stroke. Catheter ablation (CA) of atrial fibrillation (AF) leads to morphological and functional changes within the LA and LAA, some of which are not well studied. Here, we present findings regarding post-ablation changes of the LAA ostia and correlate them with various LA, LAA and left ventricular (LV) functional and morphological metrics. Methods: This retrospective analysis included patients scheduled to undergo first-time radiofrequency CA for AF. Catheter ablation techniques included PVI with or without additional ablations. Cardiac magnetic resonance imaging (CMR) was used to assess LA, LAA and LV morphology and function, including LAA ostium area, LA/LAA volume and volume index, LA ejection fraction, LA strain, and LV ejection fraction. A Kruskal-Wallis test was used for correlating LAA ostial dimensions with other LA morphological and functional metrics. The t-test or two-sample Wilcoxon test were used to compare LA and LAA morphological parameters. Results: A total of 101 patients with AF were included in this study. The mean age was 60.1 ± 11.1 years, 69% were male, the average BMI was 29.22 ± 5.08. The LAA ostial area reduced significantly from 3.84 ± 1.15 cm before ablation to 3.42 ± 0.96 cm after ablation (p=0.0004). This reduction was asymmetrical, as the minor axis length decreased from 1.92 cm to 1.77 cm without significant changes in the major axis. LVEF increased from a pre-ablation average of 48.26% to a post-ablation average of 53.62% (p=0.015). Correlation of pre-ablation LVEF and LAA ostium area showed a near-significant negative trend (r=-0.21, p=0.083). LAEF correlated negatively with LAA ostial area (r=-0.289, p=0.0057), total LA strain (r=-0.248, p=0.0185), and passive LA strain (r=-0.208, p=0.049). Conclusion: There is a significant asymmetrical reduction of the LAA ostial area after AF ablation that is independent of LVEF changes. Larger LAA ostial area was associated with lower LAEF and LA strain. Remodeling of the LAA after AF ablation may help account for reduced risk of stroke and increased cardiac function.

scholarly journals Cardiovascular Magnetic Resonance in Peripartum Cardiomyopathy: Comparison with Idiopathic Dilated Cardiomyopathy

Diagnostics ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1752
Author(s):  
Joanna Petryka-Mazurkiewicz ◽  
Karolina Kryczka ◽  
Łukasz Mazurkiewicz ◽  
Barbara Miłosz-Wieczorek ◽  
Mateusz Śpiewak ◽  
...  
Keyword(s):  
Cardiovascular Magnetic Resonance ◽  
Magnetic Resonance ◽  
Ejection Fraction ◽  
Strain Rate ◽  
Longitudinal Strain ◽  
Global Longitudinal Strain ◽  
Left Ventricular ◽  
Right Atrial ◽  
Volume Index ◽  
Left Ventricular Ejection

Background: Peripartum (PPCM) and dilated (DCM) cardiomyopathies are distinct forms of cardiac disease that share certain aspects in clinical presentation. Aim: We hypothesized that different cardiac structural changes underlie PPCM and DCM, and we aimed to investigate them with cardiovascular magnetic resonance (CMR). Methods: We included 21 PPCM patients (30.5 ± 5.9 years) and 30 female DCM patients (41.5 ± 16.8 years) matched for left ventricular ejection fraction. Biventricular and biatrial volumetric and functional parameters were assessed along with ventricular and atrial strain indices based on feature-tracking techniques. The presence of late gadolinium enhancement (LGE) was also assessed. Results: In PPCM, the left ventricular (LV) stroke volume index was lower (p = 0.04), right atrial (RA) minimal and pre-systolic volumes were higher (p < 0.01 and p = 0.02, respectively), and the total RA ejection fraction was lower (p = 0.02) in comparison to DCM. Moreover, in PPCM, the LV global longitudinal strain (p = 0.03), global circumferential strain rate (p = 0.04), and global longitudinal strain rate (p < 0.01) were less impaired than in DCM. Both PPCM and DCM patients with LGE had more dilated ventricles and more impaired LV and left atrial function than in PPCM and DCM patients without LGE. Conclusions: Subtle differences appear on CMR between PPCM and DCM. Most importantly, the RA is larger and more impaired, and LV global longitudinal strain is less reduced in PPCM than in DCM. Furthermore, similarly to DCM, PPCM patients with LGE have more dilated and impaired ventricles than patients without LGE.

scholarly journals Left atrial strain imaging evaluation: a strong predictor of atrial fibrillation recurrence after single-procedure catheter ablation

EP Europace ◽  
2021 ◽  
Vol 23 (Supplement_3) ◽  
Author(s):  
P Garcia Bras ◽  
P Silva Cunha ◽  
G Portugal ◽  
M Coutinho Cruz ◽  
B Valente ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Catheter Ablation ◽  
Ejection Fraction ◽  
Left Atrial ◽  
Strain Imaging ◽  
Af Ablation ◽  
Single Procedure ◽  
Kaplan Meier ◽  
Af Recurrence

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Identification of predictors of arrhythmia recurrence after catheter ablation of atrial fibrillation (AF) is a clinically relevant issue. Transthoracic echocardiography (TTE) is a readily accessible exam that can be useful in estimating left atrial (LA) mechanical function. The aim of this study was to evaluate LA structure and LA strain imaging at baseline and its association with AF recurrence after an index AF catheter ablation. Methods: Analysis of patients with symptomatic paroxysmal and persistent AF who underwent a single-procedure for AF ablation between 2015 and 2019 and had performed TTE in our centre prior to AF ablation. LA parameters were assessed by 2D speckle-tracking at baseline. LA diameter index (LAVi), LA ejection fraction, LA phasic strain: reservoir (LASr), conduit (LAScd) and contraction phases (LASct), as well as integrated backscatter (IBS) values were analysed. AF recurrence was documented with 12-lead ECG, 24h Holter monitoring, external loop recorder or pacemaker analysis during a 12-month follow-up period. Results: Of a total of 106 patients, 28 patients were excluded due to poor image quality. We studied 78 patients who underwent pulmonary veins isolation (PVI) (age 59 ± 14 years, 65% male, 40% with structural heart disease, 69% paroxysmal AF) with cryoballoon ablation in 53% and radiofrequency ablation in 47%. In a 12-month follow-up there was a 28% (22 patients) AF recurrence rate. Patients with AF recurrence had a baseline significantly superior LAVi (47 ± 17 mL/m2 vs. 36 ± 12 mL/m2, adjusted HR 1.04 [95% CI 1.01-1.06], p = 0.002) and lower estimated LA ejection fraction (25 ± 19.7% vs. 45.4 ± 21%, adjusted HR 0.96 [95% CI 0.94-0.98], p = 0.001). Multivariate analysis showed that baseline LA strain parameters were independent predictors of AF recurrence, as patients with AF recurrence showed impaired LASr (9.81 ± 5.79% vs 22.94 ± 9.98%, adjusted HR 0.81 [95% CI 0.73-0.89], p &lt; 0.001) and LAScd (-6.74 ± 4.11% vs. -11.85 ± 7%, adjusted HR 1.11 [95% CI 1.03-1.19], p = 0.004). In patients in sinus rhythm during baseline TTE, LASct also correlated with AF recurrence, as patients with recurrence also showed impaired baseline LASct (-7.49 ± 3.65% vs -13.74 ± 5.4%, adjusted HR 1.39 [95% CI 1.11-1.75], p = 0.005). LASr &lt;18% showed a sensitivity of 86% and specificity of 70% to predict AF recurrence. Kaplan-Meier curves (figure 1) showed that patients with LASr below the 18% cut-off had a significantly higher rate of AF recurrence. Baseline IBS did not reveal significant differences in AF recurrence (111.2 ± 23.9 dB vs. 105.9 ± 33.5 dB, HR 1.007 [0.993-1.002], p = 0.349). Conclusion: Baseline LA strain imaging parameters, including reservoir phase LA strain, were demonstrated to be independent predictors of AF recurrence after PVI. A LASr &lt;18% showed good accuracy to predict AF recurrence. Abstract Figure. Kaplan-Meier curves - time to recurrence

scholarly journals Left atrial 4D flow cardiovascular magnetic resonance: a reproducibility study in sinus rhythm and atrial fibrillation

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Marco Spartera ◽  
Guilherme Pessoa-Amorim ◽  
Antonio Stracquadanio ◽  
Adam Von Ende ◽  
Alison Fletcher ◽  
...  
Keyword(s):  
Atrial Fibrillation ◽  
Blood Pressure ◽  
Heart Rate ◽  
Cardiovascular Magnetic Resonance ◽  
Magnetic Resonance ◽  
Sinus Rhythm ◽  
Left Atrial ◽  
Peak Velocity ◽  
4D Flow ◽  
Mean Velocity

Abstract Background Four-dimensional (4D) flow cardiovascular magnetic resonance (CMR) allows sophisticated quantification of left atrial (LA) blood flow, and could yield novel biomarkers of propensity for intra-cardiac thrombus formation and embolic stroke. As reproducibility is critically important to diagnostic performance, we systematically investigated technical and temporal variation of LA 4D flow in atrial fibrillation (AF) and sinus rhythm (SR). Methods Eighty-six subjects (SR, n = 64; AF, n = 22) with wide-ranging stroke risk (CHA2DS2VASc 0–6) underwent LA 4D flow assessment of peak and mean velocity, vorticity, vortex volume, and stasis. Eighty-five (99%) underwent a second acquisition within the same session, and 74 (86%) also returned at 30 (27–35) days for an interval scan. We assessed variability attributable to manual contouring (intra- and inter-observer), and subject repositioning and reacquisition of data, both within the same session (same-day scan–rescan), and over time (interval scan). Within-subject coefficients of variation (CV) and bootstrapped 95% CIs were calculated and compared. Results Same-day scan–rescan CVs were 6% for peak velocity, 5% for mean velocity, 7% for vorticity, 9% for vortex volume, and 10% for stasis, and were similar between SR and AF subjects (all p > 0.05). Interval-scan variability was similar to same-day scan–rescan variability for peak velocity, vorticity, and vortex volume (all p > 0.05), and higher for stasis and mean velocity (interval scan CVs of 14% and 8%, respectively, both p < 0.05). Longitudinal changes in heart rate and blood pressure at the interval scan in the same subjects were associated with significantly higher variability for LA stasis (p = 0.024), but not for the remaining flow parameters (all p > 0.05). SR subjects showed significantly greater interval-scan variability than AF patients for mean velocity, vortex volume, and stasis (all p < 0.05), but not peak velocity or vorticity (both p > 0.05). Conclusions LA peak velocity and vorticity are the most reproducible and temporally stable novel LA 4D flow biomarkers, and are robust to changes in heart rate, blood pressure, and differences in heart rhythm.

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