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\begin{document}

\title{Is Epicardial Adipose Tissue Associated with Atrial Fibrillation after
Cardiac Surgery? A Systematic Review and Meta-analysis}



\author[1]{Rina Sha}%
\author[1]{Wenqiang Han}%
\author[2]{Mingjie Lin}%
\author[1]{Jingquan Zhong}%
\affil[1]{Shandong University Qilu Hospital}%
\affil[2]{Peking University First Hospital}%


\vspace{-1em}



  
  \date{June 16, 2024}


\begingroup
\let\center\flushleft
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\selectlanguage{english}
\begin{abstract}
Background: Although epicardial adipose tissue (EAT) has been proved be
associated with atrial fibrillation (AF) and post-ablation AF
recurrence, the relationship between EAT and AF after cardiac surgery
(AFACS) is not evident, yet. Objective: In the study, we aim to perform
a systematic review and meta-analysis to assess the association between
EAT and AFACS and whether it is independent of the measurement methods.
Methods: Systematic reach was implemented until May, 30, 2020, which
``atrial fibrillation'' and ``epicardial adipose tissue'' were as the
main items in electronic databases. Analysis was stratified by EAT
measurement methods into three pooled meta-analyses on 1) total EAT
volume, 2) left atrium (LA)-EAT volume and 3) EAT thickness between two
groups with and without AFACS, estimating standardized mean difference
(SMD) with a random effect model. Results: Eight articles with ten
studies (546 patients) were included. Accordingly, the results of
meta-analysis showed that EAT was higher in AFACS subjects, regardless
of the methods of EAT measurement.{[} total EAT volume: SMD = 0.56 ml;
95\% confidence interval (CI) = 0.56-1.10ml, I2 = 0.90, P=0.04; EAT
thickness: SMD = 0.85mm; 95\% CI = 0.04-1.65mm, I2 = 0.90, P=0.04;
LA-EAT volume: SMD = 0.57ml, 95\% CI = 0.23-0.92ml, I2 = 0.00,
P=0.001.{]} And there was no evidence of publication bias. Conclusion:
EAT may be a potential marker and therapeutic target for AFACS. However,
larger scale studies are still required, and evaluation is needed to for
further estimation.%
\end{abstract}%



\sloppy


\textbf{Is Epicardial Adipose Tissue Associated with Atrial Fibrillation
after Cardiac Surgery? A Systematic Review and Meta-analysis}

Rina Sha MD\textsuperscript{a}\textsubscript{,} Wenqiang Han
MD\textsuperscript{a}\textsubscript{,} Mingjie Lin
PhD\textsuperscript{a,b}\textsubscript{,} Jingquan Zhong
PhD\textsuperscript{a,c}

\begin{enumerate}
\tightlist
\item
  The Key Laboratory of Cardiovascular Remodeling and Function Research,
  Chinese Ministry of Education, Chinese National Health Commission and
  Chinese Academy of Medical Sciences, The State and Shandong Province
  Joint Key Laboratory of Translational Cardiovascular Medicine,
  Department of Cardiology, Qilu Hospital, Cheeloo College of Medicine,
  Shandong University, Jinan, China.
\item
  Peking University First Hospital, Beijing, China.
\item
  Department of Cardiology, Qilu Hospital (Qingdao), Cheeloo College of
  Medicine, Shandong University, Qingdao, China.
\end{enumerate}

Corresponding Author: Jingquan Zhong, Department of Cardiology, Qilu
Hospital of Shandong University, No. 107 Wenhuaxi Road, Jinan 250012,
China;

Phone: +86 18560086597; Fax 86(531)86927544;
E-mail:\emph{18560086597@163.com} .

Data availability statement: All data, models, and code generated or
used during the study appear in the submitted article.

Funding statement:This work was supported by Natural Science Foundation
of China (81970282); Biosense Webster Inc. (IIS-324); Shandong
Provincial Natural Science Foundation, China, (ZR2018MH002).

conflict of interest disclosure:The authors declare that they have no
competing interests.

permission to reproduce material from other sources

\par\null

\textbf{ABSTRACT}

\textbf{Background} : Although epicardial adipose tissue (EAT) has been
proved be associated with atrial fibrillation (AF) and post-ablation AF
recurrence, the relationship between EAT and AF after cardiac surgery
(AFACS) is not evident, yet.

\textbf{Objective} : In the study, we aim to perform a systematic review
and meta-analysis to assess the association between EAT and AFACS and
whether it is independent of the measurement methods.

\textbf{Methods} : Systematic reach was implemented until May, 30, 2020,
which ``atrial fibrillation'' and ``epicardial adipose tissue'' were as
the main items in electronic databases. Analysis was stratified by EAT
measurement methods into three pooled meta-analyses on 1) total EAT
volume, 2) left atrium (LA)-EAT volume and 3) EAT thickness between two
groups with and without AFACS, estimating standardized mean difference
(SMD) with a random effect model.

\textbf{Results:} Eight articles with ten studies (546 patients) were
included. Accordingly, the results of meta-analysis showed that EAT was
higher in AFACS subjects, regardless of the methods of EAT
measurement.{[} total EAT volume: SMD = 0.56 ml; 95\% confidence
interval (CI) = 0.56-1.10ml, I\textsuperscript{2} = 0.90, P=0.04; EAT
thickness: SMD = 0.85mm; 95\% CI = 0.04-1.65mm, I\textsuperscript{2} =
0.90, P=0.04; LA-EAT volume: SMD = 0.57ml, 95\% CI = 0.23-0.92ml,
I\textsuperscript{2} = 0.00, P=0.001.{]} And there was no evidence of
publication bias.

\textbf{Conclusion} : EAT may be a potential marker and therapeutic
target for AFACS. However, larger scale studies are still required, and
evaluation is needed to for further estimation.

\textbf{Keywords:}Atrial fibrillation; epicardial adipose tissue;
cardiac surgery; meta-analysis; echocardiography.

\textbf{1.Background}

Atrial fibrillation (AF) is the most common arrhythmia with an
increasing rate of morbidity and mortality \textsuperscript{1}. AF after
an cardiac surgery (AFACS) is the most frequent postoperative
complication of cardiac surgical procedures, and occurs in up to 30\%
patients \textsuperscript{2}. Although cardiac surgery-associated
morbidity and mortality reduced, the incidence of AFACS was almost
unchanged \textsuperscript{3,4}. AFACS may have a negative influence on
post-operative results in the long term. It can result in a two-fold
increase in all-cause 30-day and 6-month mortality after surgery
compared to patients with sinus rhythm\textsuperscript{5}.

Recently, more attention has been drawn to the relationship between
epicardial adipose tissue (EAT) and AF because of its inflammatory and
endocrine properties \textsuperscript{6}. EAT is an ectopic adipose
tissue, which includes fat depots located between the myocardium and the
visceral pericardium, such as pericardial fat, perivascular fat and
myocardial steatosis. According to the location, it is easy to
understand that the physiological functions of epicardial adipose
tissue, including the storage of lipids as an energy supply for
cardiomyocytes, protection of autonomic ganglia and nerve tissue, as
well as regulation in the diameter and flow of coronary
vessels\textsuperscript{7}. Therefore, we speculate that EAT may play a
central role in the pathogenesis of cardiovascular disease. A number of
studies have shown an increasing relationship between EAT and coronary
artery disease, atherosclerosis and the progression of coronary plaque
burden \textsuperscript{8-10}, major adverse cardiovascular events
\textsuperscript{11} and AF\textsuperscript{12-15}.

The relationship between EAT and AFACS was firstly described by
Charilaos et al. \textsuperscript{16} in 2014, while more than ten
studies have been undergone investigation thus far. However, these
studies have been conducted in different populations, operations
(Coronary Artery Bypass Grafting or valve replacement), with a variety
of EAT measurement methods {[}computed tomography (CT) or
echocardiography{]}, and diverse intervals of
follow-up\textsuperscript{7,16-22}. This study was the first attempt to
prove the association between AFACS and EAT, via conducting a systemic
review and meta-analysis in patients with and without AF occurrence
after cardiac surgery.

\textbf{2. Materials and Methods}

\textbf{2.1 Search Strategy}

The search was performed using the PubMed, Cochrane and Embase databases
with the start date prior to May 30, 2020. To identify and retrieve all
potentially relevant articles, the search was performed utilizing the
following expression: {[}(`epicardial adipose tissue' OR `epicardial
fat' OR `pericardial adipose tissue' OR`pericardial fat' OR `paracardial
adipose tissue' OR `paracardial fat') AND (`atrial fibrillation' OR
Arrhythmias, Cardiac'){]}. Additionally, hand searches of the reference
list of included studies were performed. We conducted this meta-analysis
in accordance with the PRISMA (Preferred Reporting Items for Systematic
Reviews and Meta-Analyses) guidelines. The systematic review registered
in PROSPERO (ID: 219400). As per the different measuring methods of EAT,
eligible studies fall into three sub-groups, including total EAT volume,
EAT thickness and LA-EAT volume.

2.2 \textbf{Eligibility criteria}

Case reports and review articles were excluded. Only English
publications in peer-reviewed journals were eligible for this
meta-analysis if they: (1) reported EAT thickness or volume with at
least one of the following main confounders: age, gender, hypertension
and Body Mass Index (BMI); (2) reported EAT parameters in two groups of
patients with and without AF occurrence after cardiac surgeries, and 3)
measured EAT by CT, magnetic resonance imaging or echocardiography. The
literature search was independently reviewed by two assessors to ensure
full compliance with the study inclusion criteria. If no agreement could
be reached, it would be decided by a third senior author.

2.3 \textbf{Study quality assessment}

The Strengthening the Reporting of Observational Studies in Epidemiology
(STROBE) Statement \textsuperscript{23} was used to evaluate the quality
of the included studies. STROBE consists of 22 items assessing quality
of the information reported in the abstract, including introduction,
study design and setting, statistical evaluation, results, discussion
and findings. The point of STROBE judgment for all included studies was
prepared based on rating scale ranging from 0 to 22 with higher score
resulting in high quality. The STROBE score was independently evaluated
by two investigators. And a third senior author was consulted when there
were discrepancies. In the case of conference abstracts, which are
without full-text, we used another 12-item STROBE checklist. All
quantity scores were included in Table 1.

2.4 \textbf{Statistical methods}

The Cochrane Q test and I squared index were used to evaluate
heterogeneity of individual studies. I\textsuperscript{2}\textgreater{}
50\% suggested high heterogeneity. In the case of high heterogeneity, a
random effect model was adopted. Considering the small size of samples,
we used sensitivity analysis to explore probable sources of
heterogeneity. The possibility of publication bias was evaluated through
the Funnel plots and Egger's regression test. Statistical analysis was
performed using STATA package vers.16 (StataCorp, College Station, TX,
USA). P\textless{}0.05 was considered statistically significant.

3. \textbf{RESULTS}

\textbf{3.1 Study selection}

The literature search resulted in 1054 records, and 3 more records were
identified through hand search of reference list of those articles.
Excluding 449 duplicated records, there are 604 remaining records, in
which 567 were not related to the topic. After reading the full texts of
the 37 remaining articles, 29 articles were excluded because of a lack
of EAT measurement (n=11), cardiac surgery (n=13), atrial fibrillation
occurrence (n=2) or comparison (n=3). Finally, the findings of the 10
studies published in 8 articles with 3 sub-groups were enrolled in the
study (Fig. 1).

\textbf{3.2 Study characteristics}

Patients with AF occurrence (n=154) and patients without AF occurrence
(n=392) post operation were named as AFACS and non-AFACS respectively.
Most \textsuperscript{7,16-19} of the studies were in the full text
format, while only one \textsuperscript{22} study was in the conference
abstract. EAT measurement involved EAT volume and LA EAT volume, which
were assessed by CT, as well as EAT thickness assessed by
echocardiography. EAT thickness was defined as an echo-free region
between the right ventricular outer wall and the visceral pericardium.
Other patient demographics and basic characteristics are described in
Table 1.

\textbf{3.3 Total epicardial fat volume}

3 studies including 309 patients were involved in EAT volume. The
comparison of total EAT volume between AFACS vs non-AFACS showed an SMD
of 0.56 ml {[}95\% confidence interval (CI) = 0.02, 1.10, P=0.04{]},
indicating that EAT volume was higher in AF occurrence patients.
Apparent significant heterogeneity was found among the studies' results
(I\textsuperscript{2} = 76\%, P = 0.01) (Fig. 2-A).

\textbf{3.4 Epicardial fat thickness}

There were 5 studies including 334 patients in measuring EAT thickness
with echocardiography. The patients with AFACS occurrence had a
significantly higher EAT thickness than those non-AFACS. (SMD=0.85mm,
95\% CI=0.04-1.65, p=0.04, I\textsuperscript{2}= 90\%) (Fig.2-B).

\textbf{3.5 Left atrium epicardial fat volume}

2 studies including 178 patients measured LA-EAT. The results showed
that there was a significant difference in the SMD between patients with
and without AF occurrence (0.57 ml, 95\% CI = 0.23--0.92, P=0.001,
I\textsuperscript{2}=0.0\%), suggesting a higher LA-EAT volume in
patients with AF occurrence. (Fig. 2-C).

\textbf{3.6 Quality assessment and publication bias}

Almost all studies in this meta-analysis were not of the same quality;
the lowest STROBE score was 17, and the highest was 20 for the articles
with full-text (Table 1). Potential sources of bias were not clear in
most of the articles. Moreover, the eligibility criteria of selection of
participants were not clear in the most of the articles. Figure 3
illustrates the relative symmetry of funnel plots of publications. At
the same time, there was no evidence of publication bias by the
calculation of the Egger test for small-study effects (P=0.160).

4. \textbf{DISCUSSION}

\textbf{4.1 Main results}

This study mainly showed an association between increasing EAT and AFACS
occurrence. To investigate the relationship between EAT volume, both
total and LA specified EAT, as well as EAT thickness and AFACS
occurrence, three different meta-analyses were conducted. The findings
were similar, which showed a positive association between increased EAT
and AFACS occurrence. Surprisingly, the similar findings in EAT
thickness and EAT volume put emphasis on the value of echocardiography
in evaluation of EAT, which is a safe and non-invasive imaging
modality\textsuperscript{24}.This study, the first attempt to prove the
association between EAT and AFACS occurrence, suggested a new possible
imaging marker to predict AFACS, which will require further research.

4.2 \textbf{EAT and AFACS}

Although the mechanism of increased EAT leading to AFACS is still
unclear, studies that demonstrated association between abundant EAT and
AF can be taken into account. EAT locates between the myocardium and
visceral pericardium, mainly on the right ventricle surface and anterior
wall of the left ventricle. It also surrounds atrioventricular grooves
and great coronary vessels, reaching the main thickness at the anterior
and lateral walls of right atrium \textsuperscript{25}. Due to the
position, It exerts local paracrine effect with findings of increased
expression of numerous inflammatory markers, and as a metabolically
active tissue modulating the adjacent myocardial tissue with abundant
ganglionated plexus of autonomic nervous
system\textsuperscript{15,26,27}. At the same time, abundant EAT has
been illustrated to be associated with fatty infiltration into adjacent
myocardium by histopathological evidence \textsuperscript{28}. Mahajan
and Zghaib et al \textsuperscript{29,30} proved EAT could cause lower
bipolar voltage and electrogram fractionation as electrophysiologic
substrates for AF. Besides, there is a speculate that the imbalance
between excessive oxidative stress and the protective effect of
adiponectin ultimately leads to the occurrence of
AF\textsuperscript{31}.

The similarity is that AFACS associates with a combination of factors:
clinical variables, intraoperative surgical variables,
electrocardiograph markers and echocardiographic predictors. In detail,
advanced age, hypertension, male gender, right coronary artery stenosis,
depressed left ventricular function, a remote history of previous AF,
combined valve replacement/coronary artery bypass grafting procedures,
prolonged aortic cross-clamp and bypass times, PR-interval, QRS
duration, abnormal left ventricular systolic and diastolic function,
left ventricular hypertrophy and increased left atrial volume may
predispose to postoperative AF \textsuperscript{32-36}. And AFACS was
also proved to be associated with the occurrence of systemic
inflammatory response syndrome with inflammatory markers, including
IL-6, IL-8, C-reactive protein, tumor necrosis factor-\selectlanguage{greek}α \selectlanguage{english}and indices of
neutrophil and platelet activation, increasing significantly in the
systemic bloodstream \textsuperscript{37,38}. Electrolyte imbalance,
especially hypokalaemia, is also considered to be a triggering factor of
AFACS \textsuperscript{37,39}.

It has been proved that obesity or a high BMI was a risk factor for
AF\textsuperscript{40,41}. Compared with non-obese people, obese
individuals have a higher probability (49\%) of suffering with AF, which
may be related with atrial enlargement, ventricular diastolic
dysfunction and increased ectopic fat depot \textsuperscript{41}. And,
in other reports, EAT was proved to be associated with AF even after
adjustment for AF risk factors, including a high
BMI\textsuperscript{13,42} . However, Echahidi et al.
\textsuperscript{37}reported that metabolic syndrome and obesity were
independent risk factors for AFACS. And EAT is associated with obesity
or high BMI\textsuperscript{42}. So, whether EAT should be regarded as
an independent trigger or a modulator of obesity of AFACS requires
further delineation.

In this study, it is known that increased EAT is associated with AFACS,
soreducing EAT maybe potential to decrease the AFACS. Antidiabetic drugs
were used for diabetes mellitus patients, which might decrease EAT and
the accumulation of EAT, including
Thiazolidinediones\textsuperscript{43}, glucagon-like peptide 1 receptor
agonists\textsuperscript{44}, Dipeptidyl peptidase-4
inhibitors\textsuperscript{45} and Sodium-dependent glucose transporters
2 inhibitors\textsuperscript{46}. Besides, weight loss by diet control
or exercise suggested to decrease EAT in interventricular groove, which
suggests a correlation with improved insulin resistance and insulin
sensitivity indexes\textsuperscript{47}. A control study (in vivo and in
vitro) performed on aortic stenosis patients who underwent a cardiac
surgery suggested that statin therapy was related to EAT thickness
reduction, which seemed secondary to the characteristics of statins
anti-inflammatory effect\textsuperscript{48}. Considering EAT containing
large amount of ganglionated plexi, an increasing number of studies
aimed at lowered AF inducibility due to injecting botulinum toxin into
canine epicardial autonomic ganglia\textsuperscript{49}. Although it was
hypothetical, still promising to be a potential novel therapeutic
option. All of these therapies not only might reduce EAT, but decrease
incidence of many other diseases, especially metabolic diseases which is
closely associated with AFACS.

Ten studies fell into sub-groups as per measuring methods of EAT,
including echocardiography and CT. Comparatively, the results measured
by CT were more preferred than echocardiography, because EAT was not
uniformly distributed around the heart. Echocardiographic probe
angulation on 2-dimensional imaging could decrease reproducibility and
accuracy, as well as unable to measure periatrial fat or total EAT
volume. And echocardiographic measurement might increase the EAT
thickness, because overlapping with perivascular adipose tissue. But
when patients had coronary atherosclerosis history, which enlarged
thickness of EAT, image analysis probably provided accurate measurement.
Accordingly, Nerlekar et.al\textsuperscript{50} proved that EAT measured
by CT compared with echocardiography revealed poor correlation, and
discrepancy was particularly obvious at higher EAT thickness.

\textbf{4.3 Cause of Heterogeneity}

In this study, obvious heterogeneity was reported in two meta-analyses
of comparing EAT volumes and EAT thickness in two groups with and
without AF occurrence. Given the obtained heterogeneity, the random
effect model was used. However, f the classification of studies into
three categories of LA-EAT volume, total EAT volume, and EAT thickness
reduced heterogeneity. Because of small sample sizes, a subgroup
analysis or meta regression could not find the possible sources among
various factors, such as female gender, cardiac surgery types, EAT
evaluation methods as well as quality of studies based on STROBE
Checklist. Moreover, BMI and age, as well as other classical AF risk
factors were additional possible sources of heterogeneity. According to
the sensitivity analysis (Table 2-a), it is suggested that the study of
Ertugrul et al. \textsuperscript{21} be one of the sources of
heterogeneity. The endpoint of other studies was AF occurrence, which
was defined according to the guidelines for the management of atrial
fibrillation of European Society of Cardiology. But in this study, AFACS
was defined as arrhythmic episodes that deteriorate hemodynamics, lasts
more than 20 minutes per episode, or lasts more than 60 minutes during a
24-hour follow up, which underestimates the occurrence of AFACS. The
study by Ertugrul et al. omitted, the sensitivity analysis results
showed there was no heterogeneity resource (Table 2-b).

4.4 \textbf{Study Limitations}

The studies observational nature limits the study that by itself had no
high position in the Evidence-Based Medicine Pyramid. And lacking access
to patient detailed data, it didn't allow us to adjust for other
covariates that may influence EAT including age, gender, and AF risk
factors of hypertension, obstructive sleep apnea hypopnea syndrome, BMI
and so on. Included studies were single-center trials with a small
sample size, which might result in unreliable data. The inclusion of
only 2 studies evaluating EAT thickness was limited because of the
potential lack of power and the inability to draw firm conclusions.
Finally, there was a significant degree of heterogeneity in the study,
which might be a limitation that has been demonstrated in other
published EAT meta-analyses with I\textsuperscript{2} values
\textgreater{}90\% \textsuperscript{51-53}.

\textbf{5. Conclusions}

This meta-analysis suggested that total and LA-EAT volumes, as well as
EAT thickness, be higher in patients with AF occurrence in comparison to
those without AF occurrence after cardiac surgery. The results showed
that EAT may be a potential biomarker and therapeutic target for AFACS,
which can be measured by both volume and thickness measurements. Further
well-designed prospective studies are required to confirm this finding
in order to guide the clinical practice.

\textbf{6.} \textbf{Author contributions:}

Rina Sha: Conceptualization, Methodology, Software, Formal analysis,
Writing -- Original Draft, Writing -- Review \& Editing;

Wenqiang Han: Methodology, Formal analysis, Investigation, Data
Curation; Mingjie Lin: Conceptualization, Writing -- Original Draft,
Writing -- Review \& Editing;

Jingquan Zhong: Conceptualization, Writing -- Review \& Editing,
Supervision, Funding acquisition.

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17. Wang Q, Min J, Jia L, et al. Human Epicardial Adipose Tissue Activin
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18. Opolski MP, Staruch AD, Kusmierczyk M, et al. Computed tomography
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19. Kogo H, Sezai A, Osaka S, Shiono M, Tanaka M. Does Epicardial
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20. Liu Q, Zhang F, Yang M, Zhong J. Increasing Level of Interleukin-1\selectlanguage{greek}β
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21. Gunturk EE, Topuz M, Serhatlio\selectlanguage{polish}ğ\selectlanguage{english}lu F, Akkaya H. Echocardiographically
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22. Ozbek K, Katlandur H, Arik B, et al. Role of red blood cell
distribution width and epicardial fat in atrial fibrillation after
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23. von Elm E, Altman DG, Egger M, Pocock SJ, G\selectlanguage{ngerman}øtzsche PC, Vandenbroucke
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24. Ghaderi F, Eshraghi A, Shamloo AS, Mousavi S. Assosiation of
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25. Ansaldo AM, Montecucco F, Sahebkar A, Dallegri F, Carbone F.
Epicardial adipose tissue and cardiovascular
diseases.\emph{International journal of cardiology.} 2019;278:254-260.

26. Mazurek T, Zhang L, Zalewski A, et al. Human epicardial adipose
tissue is a source of inflammatory mediators.
\emph{Circulation.}2003;108(20):2460-2466.

27. Rossi P, Ricci A, De Paulis R, et al. Epicardial ganglionated plexus
stimulation decreases postoperative inflammatory response in
humans.\emph{Heart rhythm.} 2012;9(6):943-950.

28. Haemers P, Hamdi H, Guedj K, et al. Atrial fibrillation is
associated with the fibrotic remodelling of adipose tissue in the
subepicardium of human and sheep atria. \emph{European heart
journal.}2017;38(1):53-61.

29. Mahajan R, Lau DH, Brooks AG, et al. Electrophysiological,
Electroanatomical, and Structural Remodeling of the Atria as
Consequences of Sustained Obesity. \emph{Journal of the American College
of Cardiology.} 2015;66(1):1-11.

30. Zghaib T, Ipek EG, Zahid S, et al. Association of left atrial
epicardial adipose tissue with electrogram bipolar voltage and
fractionation: Electrophysiologic substrates for atrial
fibrillation.\emph{Heart rhythm.} 2016;13(12):2333-2339.

31. Zhou M, Wang H, Chen J, Zhao L. Epicardial adipose tissue and atrial
fibrillation: Possible mechanisms, potential therapies, and future
directions. \emph{Pacing and clinical electrophysiology :
PACE.}2020;43(1):133-145.

32. Aranki SF, Shaw DP, Adams DH, et al. Predictors of atrial
fibrillation after coronary artery surgery. Current trends and impact on
hospital resources. \emph{Circulation.} 1996;94(3):390-397.

33. Hogue CW, Jr., Hyder ML. Atrial fibrillation after cardiac
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34. Tran DT, Perry JJ, Dupuis JY, Elmestekawy E, Wells GA. Predicting
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anesthesia.}2015;29(5):1117-1126.

35. Zhang W, Liu W, Chew ST, Shen L, Ti LK. A Clinical Prediction Model
for Postcardiac Surgery Atrial Fibrillation in an Asian
Population.\emph{Anesthesia and analgesia.} 2016;123(2):283-289.

36. Gu J, Andreasen JJ, Melgaard J, et al. Preoperative
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37. Echahidi N, Pibarot P, O'Hara G, Mathieu P. Mechanisms, prevention,
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38. Jakubová M, Mitro P, Stan\selectlanguage{polish}č\selectlanguage{ngerman}ák B, et al. The occurrence of
postoperative atrial fibrillation according to different surgical
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39. Bharucha DB, Kowey PR. Management and prevention of atrial
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40. Hatem SN. Atrial Fibrillation and Obesity: Not Just a
Coincidence.\emph{Journal of the American College of Cardiology.}
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41. Wang TJ, Parise H, Levy D, et al. Obesity and the risk of new-onset
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42. Wong CX, Sun MT, Odutayo A, et al. Associations of Epicardial,
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43. Grosso AF, de Oliveira SF, Higuchi Mde L, Favarato D, Dallan LA, da
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44. Dutour A, Abdesselam I, Ancel P, et al. Exenatide decreases liver
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45. Lima-Martínez MM, Paoli M, Rodney M, et al. Effect of sitagliptin on
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46. Sato T, Aizawa Y, Yuasa S, et al. The effect of dapagliflozin
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47. Gaborit B, Jacquier A, Kober F, et al. Effects of bariatric surgery
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48. Parisi V, Petraglia L, D'Esposito V, et al. Statin therapy modulates
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49. Pokushalov E, Kozlov B, Romanov A, et al. Long-Term Suppression of
Atrial Fibrillation by Botulinum Toxin Injection Into Epicardial Fat
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electrophysiology.} 2015;8(6):1334-1341.

50. Nerlekar N, Baey YW, Brown AJ, et al. Poor Correlation,
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51. Deng H, Bai Y, Shantsila A, Fauchier L, Potpara TS, Lip GYH.
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52. Shimabukuro M, Hirata Y, Tabata M, et al. Epicardial adipose tissue
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53. Xu Y, Cheng X, Hong K, Huang C, Wan L. How to interpret epicardial
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\textbf{Figure legends:}

Fig.1 Flow chart of included studies. EAT- epicardial adipose tissue.

Fig. 2-a random effect meta-analysis comparing total EAT volume of
patients with AF occurrence and without AF occurrence; b random effect
meta-analysis comparing EAT thickness of patients with AF occurrence and
without AF occurrence; c Random effect meta-analysis comparing LA-EAT
volume of patients with AF occurrence and without AF occurrence.
AF-atrial fibrillation. EAT- epicardial adipose tissue. LA-left atrial.

Fig.3 Illustration of funnel plot asymmetry due to heterogeneity
including all studies.

Table 1

Characteristics of the included studies.\selectlanguage{english}
\begin{longtable}[]{@{}llllllllllllll@{}}
\toprule
\begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
Reference\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
Year\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
Country\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
N\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
AF occurrence\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
AF occurrence\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
non-AF occurence\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
non-AF occurence\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
Type of EAT\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
Imaging\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
Articl type\strut
\end{minipage} & \begin{minipage}[b]{0.07\columnwidth}\raggedright\strut
quantity score\strut
\end{minipage}\tabularnewline
\midrule
\endhead
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
n\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Mean\selectlanguage{ngerman}±SD\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
n\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Mean\selectlanguage{ngerman}±SD\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Charilaos\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2014\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Greece\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
83\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
28\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
195 \selectlanguage{ngerman}± 80\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
55\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
126 \selectlanguage{ngerman}± 47\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
EAT volume (ml)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
CT\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
19/22\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Kerem\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2018\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Turkey\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
149\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
35\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
135.71\selectlanguage{ngerman}±46.78\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
114\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
118.71\selectlanguage{ngerman}±42.85\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
EAT volume (ml)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
CT\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
CA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
4/12\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Marta\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2019\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Poland\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
46\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
14\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
7.1 \selectlanguage{ngerman}± 1.2\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
32\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
7.4 \selectlanguage{ngerman}± 1.2\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
EAT thickness(mm)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Echo\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
18/22\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Qing(VHD)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2018\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
China\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
49\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
20\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
7.62\selectlanguage{ngerman}±0.69\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
57\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
7.14\selectlanguage{ngerman}±1.14\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
EAT thickness(mm)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
ECho\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
17/22\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Qing (NVHD)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2018\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
China\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
40\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
12\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
7.61\selectlanguage{ngerman}±1.01\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
6.11\selectlanguage{ngerman}±0.91\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
EAT thickness(mm)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
ECho\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
17/22\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Liu\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2019\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
China\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
74\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
37\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
5.6\selectlanguage{ngerman}±1.1\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
37\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
5\selectlanguage{ngerman}±1.3\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
EAT thickness(mm)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Echo\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
20/22\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Ertugrul\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2020\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Turkey\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
125\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
45\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
7.28\selectlanguage{ngerman}±0.57\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
80\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
6.42\selectlanguage{ngerman}±0.35\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
EAT thickness(mm)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Echo\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
19/22\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Adam\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2015\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Poland\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
102\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
24\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
5.6\selectlanguage{ngerman}±3.0\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
78\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
4.0\selectlanguage{ngerman}±2.5\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
LA EAT volume(ml)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
CT\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
19/22\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Hiroko\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
2018\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Japan\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
77\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
21\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
177.7\selectlanguage{ngerman}±69.8\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
56\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
165.9\selectlanguage{ngerman}±65.9\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
EAT volume (ml)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
CT\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
18/22\strut
\end{minipage}\tabularnewline
\begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
Japan\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
77\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
21\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
55.65\selectlanguage{ngerman}±23.15\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
56\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
43.8\selectlanguage{ngerman}±21.6\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
LA EAT volume(ml)\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
CT\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
OA\strut
\end{minipage} & \begin{minipage}[t]{0.05\columnwidth}\raggedright\strut
18/22\strut
\end{minipage}\tabularnewline
\bottomrule
\end{longtable}

LA: left atrium; EAT: epicardial adipose tissue, CT: computed
tomography; OA: original article; CA: conference abstract; VHD: valvular
heart disease; NVHD: non-valvular heart disease;

Notice: Unit of the volume and thickness variables are milliliter (ml)
and millimeter (mm), respectively

Table 2-a

Results of sensitivity analysis\selectlanguage{english}
\begin{longtable}[]{@{}llll@{}}
\toprule
Study omitted & Estimate & 95\% Conf. Interval & 95\% Conf.
Interval\tabularnewline
\midrule
\endhead
Charilaos (2014) & 0.66642737 & 0.50066859 & 0.8321861\tabularnewline
Kerem (2018) & 0.78323132 & 0.61100805 & 0.95545459\tabularnewline
Hiroko(2018) & 0.77475089 & 0.60951865 & 0.93998313\tabularnewline
Marta(2019) & 0.78021538 & 0.61814988 & 0.94228089\tabularnewline
Qing (VHD(2018) & 0.73446065 & 0.57137752 & 0.89754385\tabularnewline
Qing (NVHD)(2018) & 0.67772061 & 0.51735497 & 0.83808631\tabularnewline
Liu(2019) & 0.74463749 & 0.57779455 & 0.91148037\tabularnewline
Ertugrul(2020) & 0.53569818 & 0.36762503 & 0.70377135\tabularnewline
Adam(2015) & 0.72998023 & 0.56324661 & 0.89671385\tabularnewline
Hiroko(2018) & 0.73505941 & 0.57005066 & 0.9000591\tabularnewline
Combined & 0.7163113 & 0.5593527 & 0.8732699\tabularnewline
\bottomrule
\end{longtable}

b. Results of sensitivity analysis leaving out the study by Ertugrul et
al\selectlanguage{english}
\begin{longtable}[]{@{}llll@{}}
\toprule
Study omitted & Estimate & 95\% Conf. Interval & 95\% Conf.
Interval\tabularnewline
\midrule
\endhead
Charilaos (2014) & 0. 45323172 & 0.27421573 & 0..63224769\tabularnewline
Kerem (2018) & 0.57125425 & 0.38401416 & 0.75849438\tabularnewline
Hiroko(2018) & 0.58101773 & 0.40266448 & 0.75937104\tabularnewline
Marta(2019) & 0.59586072 & 0.42147139 & 0.77025008\tabularnewline
Qing (VHD(2018) & 0.54008275 & 0.71574193 & 0.71574193\tabularnewline
Qing (NVHD)(2018) & 0.48201472 & 0.30973798 & 0.65429145\tabularnewline
Liu(2019) & 0.54138154 & 0.36099765 & 0.72176534\tabularnewline
Adam(2015) & 0.52456343 & 0.36762503 & 0.70377137\tabularnewline
Hiroko(2018) & 0.53541028 & 0.35734367 & 0.7134769\tabularnewline
Combined & 0.5356982 & 0.5593527 & 0.8732699\tabularnewline
\bottomrule
\end{longtable}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/Figure-1/Figure-1}

\end{center}
\end{figure}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/Figure-2-a/Figure-2-a}

\end{center}
\end{figure}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/Figure-2-b/Figure-2-b}

\end{center}
\end{figure}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/Figure-2-c/Figure-2-c}

\end{center}
\end{figure}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/Figure-3/Figure-3}

\end{center}
\end{figure}

\selectlanguage{english}
\FloatBarrier
\end{document}

