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\begin{document}

\title{The prognostic outcome of Atypical Atrial Flutter following a single
electrophysiology study and ablation}



\author[1]{Sudeepthi Reddy Mekala}%
\author[1]{Sumedh Iyengar}%
\author[2]{Molly Klanderman}%
\author[1]{Mohammed Elzamar}%
\author[3]{Fred Kusumoto}%
\author[4]{Samuel Asirvatham}%
\author[1]{Win-Kuang Shen}%
\author[1]{Arturo Valverde}%
\author[1]{Komandoor Srivathsan}%
\affil[1]{Mayo Clinic Hospital}%
\affil[2]{Mayo Clinic Scottsdale}%
\affil[3]{Mayo Clinic in Florida}%
\affil[4]{Mayo Clinic Minnesota}%


\vspace{-1em}



  
  \date{May 24, 2024}


\begingroup
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\selectlanguage{english}
\begin{abstract}
\textbf{Background:} Atypical Atrial Flutter (AAFL) prevalence is
increasing due to the escalating Atrial Fibrillation (AF) ablations and
cardiac surgeries. We wanted to explore the outcome of the AAFL
ablation, considering the recent changes in mapping and ablation.
\textbf{Methods:} This study was approved by the Institutional Review
Board (IRB) of Mayo Clinic hospital. We retrospectively studied 419
patients who had undergone AAFL ablation at Mayo Clinic from January
2017 to June 2022. Thirteen patients declined research authorization,
and 19 patients were lost to follow-up during the 90-day blanking
period, resulting in a sample size of 387. The median follow-up time for
patients was 25.7 months (95\% CI 23.7, 32.3). \textbf{Results:}
Recurrent symptoms with documentation of atrial arrhythmia Occurred in
226/387 (58.4\%) patients, of which 151/226 (66.8\%) occurred within the
first year. The median time to recurrence was 8.5 months (max 57.8
months). Eleven patients died during the study period, 9 of whom
experienced recurrence prior to death. Overall, the median
recurrence-free survival (RFS) time was 16.6 months (95\% CI 13.2, 20.0)
with a 1-year RFS rate of 57.2\% (95\% CI 52.2, 62.7\%). Acute
termination occurred 324/387 (83.7\%) during the ablation. The 1-year
RFS rate was 58.9\% (95\% CI 53.5\%, 64.9\%) for patients with acute
termination and 49.0\% (95\% CI 37.9\%, 63.4\%) for those without acute
termination. The rate was not significantly different based on acute
termination status (p = 0.11). \textbf{Conclusions:} The one-year RFS
rate of 57.2\% following AAFL ablation, even though 83.7\% achieved
acute termination during the procedure, signifies the extent of the
underlying substrate abnormalities.%
\end{abstract}%



\sloppy


Sudeepthi Reddy Mekala\textsuperscript{1}, MBBS

Sumedh Iyengar\textsuperscript{1}, MBBS

Molly Klanderman\textsuperscript{2}, Ph.D.

Mohammed Elzamar\textsuperscript{1}, MBBS

Fred Kusumoto\textsuperscript{3}, MD

Samuel Asirvatham\textsuperscript{4}, MD

Win Shen, MD\textsuperscript{1}, FHRS

Arturo Valverde MD\textsuperscript{1}, FHRS

Komandoor Srivathsan\textsuperscript{1}, MD

\textbf{Author Affiliations:} \textsuperscript{1}The Division of
Cardiovascular Diseases, Mayo Clinic Hospital, Phoenix, Arizona.

\textsuperscript{2}Mayo Clinic Department of Quantitative Health
Sciences, Scottsdale, AZ

\textsuperscript{3}Mayo Clinic, Jacksonville, Florida

\textsuperscript{4}Mayo Clinic, Rochester, Minnesota

\textbf{Manuscript word count: 1497}

\textbf{Figures: 2}

\textbf{Tables: 2}

\textbf{Financial support:} This Research received no specific grant
from funding agencies in public, commercial, or not-for-profit sectors.
(The CV department provided statistics support.)

\textbf{Declaration of Conflict of Interest:} None

\textbf{Address for Correspondence:}

Srivathsan Komandoor, M.D

Division of Cardiovascular Diseases

Mayo Clinic Hospital

5777 East Mayo Boulevard,

Phoenix, AZ 85054

Email address:\emph{srivathsan.komandoor@mayo.edu}



\textbf{Abstract:}

\textbf{Background:} Atypical Atrial Flutter (AAFL) prevalence is
increasing due to the escalating Atrial Fibrillation (AF) ablations and
cardiac surgeries. We wanted to explore the outcome of the AAFL
ablation, considering the recent changes in mapping and ablation.

\textbf{Methods:} This study was approved by the Institutional Review
Board (IRB) of Mayo Clinic hospital. We retrospectively studied 419
patients who had undergone AAFL ablation at Mayo Clinic from January
2017 to June 2022. Thirteen patients declined research authorization,
and 19 patients were lost to follow-up during the 90-day blanking
period, resulting in a sample size of 387. The median follow-up time for
patients was 25.7 months (95\% CI 23.7, 32.3).

\textbf{Results:} Recurrent symptoms with documentation of atrial
arrhythmia Occurred in 226/387 (58.4\%) patients, of which 151/226
(66.8\%) occurred within the first year.~ The median time to recurrence
was 8.5 months (max 57.8 months). Eleven patients died during the study
period, 9 of whom experienced recurrence prior to death. Overall, the
median recurrence-free survival (RFS) time was 16.6 months (95\% CI
13.2, 20.0) with a 1-year RFS rate of 57.2\% (95\% CI 52.2, 62.7\%).
Acute termination occurred 324/387 (83.7\%) during the ablation. The
1-year RFS rate was 58.9\% (95\% CI 53.5\%, 64.9\%) for patients with
acute termination and 49.0\% (95\% CI 37.9\%, 63.4\%) for those without
acute termination. The rate was not significantly different based on
acute termination status (p = 0.11).

\textbf{Conclusions:} The one-year RFS rate of 57.2\% following AAFL
ablation, even though 83.7\% achieved acute termination during the
procedure, signifies the extent of the underlying substrate
abnormalities.

\textbf{Keywords:} Atypical atrial flutter, Atypical atrial flutter
ablation, Atrial fibrillation, Radiofrequency ablation, AV-nodal
ablation, Pacemaker, Mitral valve repair, Surgical MAZE procedure,
Structural heart defect.

\textbf{Abbreviations:}

AAFL: Atypical atrial flutter

AFL: Atrial flutter

AF: Atrial fibrillation

MRAT: Macro-reentrant atrial tachycardias

CTI: Cavo-Tricuspid Isthmus

EP study: Electrophysiology study

RF: Radiofrequency

AV-Node: Atrioventricular node

AAD: Anti-arrhythmic drug

RA: Right atrium

LA: Left atrium

RFS: Recurrence-free survival

IQR: interquartile range

\textbf{1. Introduction:}

The definition of Atypical Atrial Flutter (AAFL) includes a broad
spectrum of macro-reentrant atrial tachycardias (MRAT) in which the
wavefront does not include the Cavo-Tricuspid Isthmus (CTI) part of the
tricuspid annulus \textbf{{[}1{]}} .

There is a substantial increase in the incidence of AAFL as an
iatrogenic problem in patients who have had a catheter ablation
procedure for treating AF or a surgical MAZE procedure \textbf{{[}2{]}}
.

In AAFL, especially in patients who had surgery or catheter ablation, an
electrophysiology study (EP study) is the only way to unveil the
mechanism \textbf{{[}3{]}} . An electrophysiology study, including
entrainment characteristics and high-density mapping consistent with
reentry, must confirm the ultimate diagnosis of AAFL \textbf{{[}4{]}} .

Catheter ablation is frequently utilized due to lack of efficacy of
medications or significant symptoms and deteriorating left ventricular
function \textbf{{[}4,5{]}} .

Entrainment and point-to-point map acquisition with large tip (8mm)
catheter ablation was common until recently. However, in the last few
years, a more comprehensive understanding of propagation and critical
zones has been possible by high-density electroanatomical mapping
utilizing small-diameter, multipolar catheters. Multipolar maps may have
advantages over traditional point-by-point voltage maps. One such
advantage is higher mapping resolution, which facilitates the detection
of slow conduction zones. Additionally, multipolar maps improve the
accuracy and speed of mapping procedures due to the function of smaller
electrodes. Finally, pace capture can be achieved at the lower output
due to increased electrical density \textbf{{[}6,7{]}.} Therefore, we
wanted to explore the outcome of the AAFL ablation, considering the
recent changes in mapping and ablation.

\textbf{2. Methods:}

This study was approved by the Institutional Review Board (IRB) of Mayo
Clinic hospital.

\textbf{Study cohort:} This study is a retrospective analysis of
patients that underwent AAFL ablation in the past 5 years (2017-2022) at
different sites of Mayo Clinic. High-density activation sequence mapping
and small-diameter multipolar catheter usage have become more prevalent
in the past 5 years. Therefore, we wanted to study the impact of our
contemporary practice on the overall outcome of AAFL.

\textbf{Ablation and Follow-up:} All included patients had Intra Cardiac
Echo (ICE), a multipolar small diameter catheter used for mapping, and
irrigated Radiofrequency (RF) catheter for ablation. Successful ablation
was defined as the termination of AAFL during RF energy application
(either without cycle length change or lengthening) and the inability to
reinduce the index AAFL. The termination was not considered successful
if the index arrhythmia terminated due to a premature beat or cycle
length shortening. All included patients were routinely followed up for
any clinically relevant atrial arrhythmia recurrence according to the
clinical standards of care. If prompted by symptoms, they were seen at
the outpatient clinic or via virtual appointment. Routinely scheduled
appointments were at 1, 3, and 12 months. Besides symptomatic
recurrences, routine electrocardiograms and Holter monitoring were
utilized to confirm recurrent events, even if unaccompanied by symptoms.
The primary outcome of interest was one-year recurrence-free survival in
all symptomatic event-based recordings or opportunistic, incidental
routine monitoring. Early recurrent symptoms during the 90-day blanking
period were excluded.

\textbf{Statistical analysis:} Continuous variables were summarized
using median and interquartile range (IQR), and categorical variables
were summarized using frequency and percentage. A Kaplan Meier curve
with log-rank analysis examined the primary outcome, recurrence-free
survival. Patients were censored as of the date of the last follow-up,
and a p-value of \textless{}0.05 was considered significant. Statistical
software R 4.1.2 was used for analysis.

\textbf{3. Results:}

\subsection*{Demographics and clinical
characteristics:}

{\label{demographics-and-clinical-characteristics}}

A total of 419 patients had an ablation at Mayo Clinic for AAFL from
January 2017 to June 2022. A total of 13 patients were excluded due to
denied research authorization. Additionally, 19 patients were lost to
follow-up during the 90-day blanking period and excluded, resulting in a
total sample size of 387. The median follow-up time for patients was
25.7 months (95\% CI 23.7, 32.3).

The demographics and clinical characteristics are given in \textbf{Table
1} . The median age was 68.0 (IQR 60.0, 74.0), and 32.6\% of patients
were female.

\textbf{Ablation Characteristics} : Bidirectional block following a
linear line was confirmed at the end of the ablation in 66.06\%
(255/386) of the patients. In 1.2\% (5/386) of the patients, only
unidirectional block could be achieved. In 5.6\% (22/386) of the
patients, bidirectional block could not be achieved at the end of the
ablation. In 26.9\% (104/386) of the patients, the confirmation of the
bidirectional block was not documented.

\subsection*{Recurrence-free survival:}

{\label{recurrence-free-survival}}

Recurrent events following the ablation occurred in 226/387 (58.4\%)
patients after a median of 8.5 months post-ablation (max 57.8 months),
of which \emph{151/226 (66.8\%) occurred within the first year} . During
the study period, 11/387 patients died, 9 of whom experienced recurrence
prior to death. The median recurrence-free survival (RFS) time was 16.6
months (95\% CI 13.2, 20.0). The 1-year RFS was 57.2\% (95\% CI 52.2\%,
62.7\%).

\textbf{Figure 1} shows the Kaplan-Meier curve for the probability of
RFS over time.

\subsubsection*{Recurrence-free survival based on acute termination
status:}

{\label{recurrence-free-survival-based-on-acute-termination-status}}

Acute termination occurred in 324/387 (83.7\%) during the
ablation.\textbf{Figure 2} shows the Kaplan-Meier curve for the
probability of RFS over time-based on acute termination or lack of
termination during ablation. For patients with acute termination, the
1-year RFS rate was 58.9\% (95\% CI 53.5\%, 64.9\%). For patients
without acute termination, the 1-year RFS rate was 49.0\% (95\% CI
37.9\%, 63.4\%). The RFS was not significantly different based on acute
termination status (p = 0.11).

\subsection*{Recurrence:}

{\label{recurrence}}

For patients who experienced recurrence following the ablation, 48.7\%
experienced a different AAFL, and 40.7\% experienced AF. 51.8\% of
patients were cardioverted, 14.6\% had an AV node ablation, 35.0\%
underwent a repeat ablation \textbf{(Table 2), and} 44.7\% were on
anti-arrhythmic drugs after index ablation.

\textbf{4. Discussion:}

\textbf{Cause of AAFL: Table 1} shows 66.1\% had undergone prior
ablation for AF/typical AFL; 6.5\% had a surgical correction for
congenital heart disease; 15.2\% had mitral/ aortic valve
repair/replacement; 7.8\% had undergone surgical MAZE procedure and the
rest 7\% with other cardiac interventions. This cohort is representative
of the referral patterns seen in many centers that frequently deal with
AAFL.

This is the largest cohort of patients who underwent the contemporary
AAFL mapping and ablation practice. Ablation of AF begets more AAFL is
the new norm.

\textbf{Outcome:}

\textbf{1. Acute:} 83.7\% achieved acute termination of the flutter
during the ablation, and the rest required electrical cardioversion to
achieve sinus status at the end of the ablation. The recurrence-free
survival rate was not significantly different based on acute termination
status (p = 0.11), as mentioned in \textbf{Figure 2} . Acute termination
and lack of inducibility are the common standards to determine success
in the EP lab, particularly for reentrant
arrhythmia\textbf{{[}8,9,10{]}} . The most important finding is that the
index macroreentrant arrhythmia's termination does not predict
recurrence-free survival. Lack of inducibility is not an indicator of
recurrence-free survival is another significant finding as it is
commonly used as an endpoint for ablation.

\textbf{2. Follow-up:}

\textbf{Recurrence:} For patients with acute termination, the 1-year
recurrence-free survival rate was 58.9\% (95\% CI 53.5\%, 64.9\%). For
patients without acute termination, the 1-year recurrence-free survival
rate was 49.0\% (95\% CI 37.9\%, 63.4\%). During the study, 58.4\% had
recurrent arrhythmic symptoms following ablation, not including the
immediate blanking phase (90-day period). Index arrhythmia was
terminated in most patients, but significant recurrent other atrial
arrhythmias were noticed. AAFL is the most common form of arrhythmic
recurrence, followed by AF. As the recurrence was assessed only by
surface recording, it is difficult to discern whether it is due to the
original or new arrhythmia mimicking the pattern. Based on the
replication of morphology from pre-procedural flutter tracings, the
recurrence of the targeted flutter is extremely low (2.7\%). Ongoing
follow-up beyond 1-year showed higher rates of recurrences. Recurrence
is not due to recently ablated AAFL is the other useful finding.

Recurrences of new arrhythmia suggest progressive substrate changes from
the native disease or additional new substrate due to the ablation.
Utilizing linear lines to connect to electrically inert or anatomical
barriers may influence the recurrence rate. Any non-transmural lesion in
a linear line can become a substrate for reentrant arrhythmia. Assessing
the block across a linear line is operator-dependent. Most of the block
across a linear line was confirmed with a multipolar catheter time delay
and or activation reversals. After the procedure, recovery of conduction
across the line may contribute to recurrence.

\textbf{Management of recurrent arrhythmias:} The recurrences were
managed by anti-arrhythmic drugs, electrical cardioversion, repeat
ablation, or as the final resort, AV-node ablation. Repeat ablation was
required in 35\% of the cases. AV-Nodal ablation is the last resort in
some patients (14.6\%) who failed to achieve sinus rhythm despite the
flutter ablation. Achieving sinus rhythm was difficult in a small number
of patients, and they were counseled to accept that the arrhythmia was
likely their new normal if the rate was under control.

\textbf{5. Limitations:}

A blanking period of 90 days is utilized for post-AAFL ablation, similar
to AF ablation, where the arrhythmia recurrences within the period are
disregarded. This blanking interval is debatable for a reentrant
arrhythmia, but the period was chosen for consistency with AF studies.
Any interventions in this period, such as repeat procedures and AV-nodal
ablation, are not considered.

Besides symptom-based recording, routine Holter monitoring at periodic
intervals and snapshot ECGs were used as markers of recurrence. However,
continuous recording with a loop recorder or implanted device such as a
pacemaker may have detected a higher recurrence rate.

\textbf{6.} \textbf{Conclusions:}

The one-year RFS rate of 57.2\% following AAFL ablation, even though
83.7\% achieved acute termination during the procedure, signifies the
extent of the substrate abnormalities.

\textbf{Acknowledgments:} None

\textbf{References:}

Cos\selectlanguage{ngerman}ío F. G. (2017). Atrial Flutter, Typical and Atypical: A
Review.~\emph{Arrhythmia \& electrophysiology review} ,~\emph{6} (2),
55--62. https://doi.org/10.15420/aer.2017.5.2

Garan H. (2008). Atypical atrial flutter. \emph{Heart rhythm} ,\emph{5}
(4), 618--621. https://doi.org/10.1016/j.hrthm.2007.10.031

Kalman, J. M., Olgin, J. E., Saxon, L. A., Lee, R. J., Scheinman, M. M.,
\& Lesh, M. D. (1997). Electrocardiographic and electrophysiologic
characterization of atypical atrial flutter in man: use of activation
and entrainment mapping and implications for catheter
ablation.\emph{Journal of cardiovascular electrophysiology} , \emph{8}
(2), 121--144. https://doi.org/10.1111/j.1540-8167.1997.tb00775.x

Morady, F., Oral, H., \& Chugh, A. (2009). Diagnosis and ablation of
atypical atrial tachycardia and flutter complicating atrial fibrillation
ablation. \emph{Heart rhythm} , \emph{6} (8 Suppl), S29--S32.
https://doi.org/10.1016/j.hrthm.2009.02.011

Ko Ko, N. L., Sriramoju, A., Khetarpal, B. K., \& Srivathsan, K. (2022).
Atypical atrial flutter: review of mechanisms, advances in mapping and
ablation outcomes. \emph{Current opinion in cardiology} , \emph{37} (1),
36--45. https://doi.org/10.1097/HCO.0000000000000924

Anter, E., Tschabrunn, C. M., \& Josephson, M. E. (2015).
High-resolution mapping of scar-related atrial arrhythmias using smaller
electrodes with closer interelectrode spacing. \emph{Circulation.
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https://doi.org/10.1161/CIRCEP.114.002737

Tschabrunn, C. M., Roujol, S., Dorman, N. C., Nezafat, R., Josephson, M.
E., \& Anter, E. (2016). High-Resolution Mapping of Ventricular Scar:
Comparison Between Single and Multielectrode
Catheters.\emph{Circulation. Arrhythmia and electrophysiology} ,
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https://doi.org/10.1161/CIRCEP.115.003841

Haïssaguerre, M., Sanders, P., Hocini, M., Takahashi, Y., Rotter, M.,
Sacher, F., Rostock, T., Hsu, L. F., Bordachar, P., Reuter, S., Roudaut,
R., Clémenty, J., \& Jaïs, P. (2005). Catheter ablation of long-lasting
persistent atrial fibrillation: critical structures for
termination.\emph{Journal of cardiovascular electrophysiology} ,
\emph{16} (11), 1125--1137.
https://doi.org/10.1111/j.1540-8167.2005.00307.x

O'Neill, M. D., Wright, M., Knecht, S., Jaïs, P., Hocini, M., Takahashi,
Y., Jönsson, A., Sacher, F., Matsuo, S., Lim, K. T., Arantes, L.,
Derval, N., Lellouche, N., Nault, I., Bordachar, P., Clémenty, J., \&
Haïssaguerre, M. (2009). Long-term follow-up of persistent atrial
fibrillation ablation using termination as a procedural
endpoint.\emph{European heart journal} , \emph{30} (9), 1105--1112.
https://doi.org/10.1093/eurheartj/ehp063

Jaïs, P., Hocini, M., Sanders, P., Hsu, L. F., Takahashi, Y., Rotter,
M., Rostock, T., Sacher, F., Clementy, J., \& Haissaguerre, M. (2006).
Long-term evaluation of atrial fibrillation ablation guided by
noninducibility. \emph{Heart rhythm} , \emph{3} (2), 140--145.
https://doi.org/10.1016/j.hrthm.2005.11.012\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/image1/image1}

\end{center}
\end{figure}

\emph{Figure 1. Recurrence-free survival}\selectlanguage{english}
\begin{figure}[H]
\begin{center}
\includegraphics[width=0.70\columnwidth]{figures/image2/image2}

\end{center}
\end{figure}

\emph{Figure 2. Recurrence-free survival based on acute termination
status}

Table 1. Demographics and Clinical Characteristics\selectlanguage{english}
\begin{longtable}[]{@{}ll@{}}
\toprule
& Overall (N=387)\tabularnewline
Sex (Male) & 261 (67.4\%)\tabularnewline
Age at procedure &\tabularnewline
Median (Q1, Q3) & 68.0 (60.0, 74.0)\tabularnewline
Range & 27.0 - 87.0\tabularnewline
Hypertension & 280 (72.4\%)\tabularnewline
Diabetes Mellitus (Type II) & 47 (12.1\%)\tabularnewline
Coronary artery disease & 74 (19.1\%)\tabularnewline
Congestive heart failure & 152 (39.3\%)\tabularnewline
Dyslipidemia & 244 (63.0\%)\tabularnewline
Thyroid status &\tabularnewline
Amiodarone Induced Hyper & 1 (0.3\%)\tabularnewline
Hyper & 2 (0.5\%)\tabularnewline
Hypo & 63 (16.3\%)\tabularnewline
None & 317 (81.9\%)\tabularnewline
Subclinical Hypo & 4 (1.0\%)\tabularnewline
Obstructive sleep apnea & 185 (47.8\%)\tabularnewline
Chronic obstructive pulmonary disease & 40 (10.3\%)\tabularnewline
Chronic kidney disease & 78 (20.2\%)\tabularnewline
Pre-procedure creatinine &\tabularnewline
Median (Q1, Q3) & 1.1 (0.9, 1.2)\tabularnewline
Range & 0.6 - 4.9\tabularnewline
Atrial fibrillation/flutter status &\tabularnewline
History of atrial fibrillation/flutter without intervention & 89
(23.0\%)\tabularnewline
No history of atrial fibrillation/flutter & 42 (10.9\%)\tabularnewline
Previous ablation for atrial fibrillation/flutter & 256
(66.1\%)\tabularnewline
Congenital heart disease & 25 (6.5\%)\tabularnewline
Valve repair/replacement & 59 (15.2\%)\tabularnewline
MAZE & 30 (7.8\%)\tabularnewline
VT11Ventricular tachycardia/PVC22Premature ventricular contraction
ablation & 6 (1.6\%)\tabularnewline
AVNRT33Atrioventricular nodal reentrant tachycardia ablation & 5
(1.3\%)\tabularnewline
HOCM44Hypertrophic obstructive cardiomyopathy s/p myectomy & 12
(3.1\%)\tabularnewline
WPW55Wolff-Parkinson-White ablation & 1 (0.3\%)\tabularnewline
Other cardiac symptoms & 1 (0.3\%)\tabularnewline
Ablation success & 323 (83.5\%)\tabularnewline
Acute termination & 324 (83.7\%)\tabularnewline
Lack of inducibility & 385 (99.5\%)\tabularnewline
Use of DCCV66Direct current cardioversion during procedure
&\tabularnewline
None & 322 (83.2\%)\tabularnewline
Hemodynamic Instability & 2 (0.5\%)\tabularnewline
Failure of termination & 63 (16.3\%)\tabularnewline
\bottomrule
\end{longtable}



Table 2. Nature of recurrence and interventions for patients with
recurrence\selectlanguage{english}
\begin{longtable}[]{@{}ll@{}}
\toprule
& Overall (N=226)\tabularnewline
Nature of recurrence &\tabularnewline
Atrial fibrillation & 92 (40.7\%)\tabularnewline
Different atypical flutter & 110 (48.7\%)\tabularnewline
Same and different atypical flutter & 4 (1.8\%)\tabularnewline
Same atypical flutter & 6 (2.7\%)\tabularnewline
Typical flutter & 6 (2.7\%)\tabularnewline
Unspecified & 8 (3.5\%)\tabularnewline
Direct current cardioversion & 104 (46.0\%)\tabularnewline
AV Node ablation & 33 (14.6\%)\tabularnewline
Repeat ablation & 79 (35.0\%)\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/Figure-2}

\end{center}
\end{figure}

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

