Sex-Based Differences of Left Atrium: Impact on Atrial Fibrillation Ablation.
Conditions: Atrial Fibrillation (AF)
Sponsor: Centro Medico Teknon

Sex-Tailored BY-LAWT AF-Ablation 
 
 
 
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Sex-Based Differences in Left Atrial 
anatomical characteristics: Impact on 
Atrial Fibrillation Ablation Outcomes – 
A Retrospective Multicenter Analysis 
TRIAL IDENTIFIER: Sex-Tailored BY-LAWT AF-Ablation 
 
PROTOCOL VERSION 1.0 (August 7, 2025) 
 
 
 
Protocol 
Version 
Date of change 
Description and comments 
Control 
1.0 
Aug 07, 2025 
First version 
RM, DT, GF 
 
 
 

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0. Study Investigators and participating centers 
1. Antonio Berruezo. Heart Institute, Teknon Medical Center, Barcelona (Spain). 
Mail: antonio.berruezo@quironsalud.es 
2. Giulio Falasconi. Heart Institute, Teknon Medical Center, Barcelona (Spain). Mail: 
giuliofalasconi@gmail.com 
3. Diego Penela. Heart Institute, Teknon Medical Center, Barcelona (Spain).  Mail: 
dpenela30@gmail.com 
4. David Soto-Iglesias. Heart Institute, Teknon Medical Center, Barcelona (Spain). 
Mail: sotin1985@gmail.com 
5. Juan Fernández-Armenta Pastor, MD, PhD. Co-investigator, Hospital 
Universitario Puerta del Mar, Cadiz, Spain. Mail: juanfdezarmenta@gmail.com   
6. Etelvino Silva, M.Eng., PhD Co-investigator, Hospital Universitario Puerta del 
Mar, Cadiz, Spain. Co-investigator, esilgar@gmail.com  
7. Paula Franco-Ocana. Heart Institute, Teknon Medical Center, Barcelona (Spain). 
Mail: PFrancoO@ITS.JNJ.com 
8. Dario Turturiello. Heart Institute, Teknon Medical Center, Barcelona 
(Spain).Mail: dario.turturiello@gmail.com 
9. Roberta Mea. Heart Institute, Teknon Medical Center, Barcelona (Spain). Mail: 
Roberta.mea.rm@gmail.com 
10. Alessia Chiara Latini. Heart Institute, Teknon Medical Center, Barcelona (Spain). 
Mail: latinialessiachiara@gmail.com 
11. Federico Landra. Heart Institute, Teknon Medical Center, Barcelona (Spain). Mail: 
fede.landra95@gmail.com 
12. Bruno Tonello. Heart Institute, Teknon Medical Center, Barcelona (Spain). Mail: 
brunotonello_94@hotmail.com 
13. Lautaro Sanchez Molla. Heart Institute, Teknon Medical Center, Barcelona 
(Spain). Mail: sanchezmollalautaro@gmail.com 
 
 

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0.1 Coordinating clinical investigator 
This will be the principal investigator of the study and the person who will take the decision to 
submit the report for publication, and will have ultimate authority over all the activities: 
 
Dr. Antonio Berruezo  
Teknon Medical Center 
C/Vilana, 12 
08022 – Barcelona (Spain) 
Tel: +34 932 90 62 00 
Mail: antonio.berruezo@quironsalud.es  
 
0.2 Responsibilities of the coordinating center 
Heart Institute, Teknon Medical Center is the coordinating center that will manage the data and 
perform statistical analysis.  
 

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1. INTRODUCTION 
Pulmonary vein isolation (PVI) is a well-established therapeutic strategy for managing both 
paroxysmal atrial fibrillation (PAF) and persistent atrial fibrillation (PeAF) (1). While 
generally effective, long-term outcomes remain heterogeneous across patients. Technological 
innovations, such as the use of electroanatomical mapping systems, have further improved the 
efficacy, efficiency, and safety of PVI(2). 
 
The goal of PVI is to create continuous, transmural, and permanent lesions. Non-transmural 
ablation is a major determinant of post-ablation AF recurrence. In fact, pulmonary vein (PV) 
reconnection is often attributed to insufficient lesion depth. (3) 
Personalizing ablation based radiofrequency titration according to patient-specific anatomical 
features—such as left atrial wall thickness (LAWT) assessed by pre-procedural multidetector 
computed tomography (MDCT)—has proven feasible, effective, and safe(4). In such a tailored 
approach, anatomical sex differences, particularly in left atrial volume (LAV), LAWT, and 
intramyocardial fat (inFAT) volume and distribution, may impact procedural characteristics 
and long-term arrhythmia-free survival(5) (6, 7) 
 
The aim of our study is to assess sex-related differences in patients who underwent a first 
ablation procedure for paroxysmal or persistent AF, guided by the personalized ablation 
strategy of the BY-LAWT protocol. Specifically, we aim to compare anatomical characteristics, 
procedural parameters, and clinical outcomes between sexes.(8, 9) 
 
2. OBJECTIVES 
2.1 Research Hypothesis 
We hypothesize that, among patients undergoing a first catheter ablation for PAF or PeAF, 

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women exhibit significantly lower LAWT, LAV, and inFAT compared to men. These 
anatomical differences may lead to procedural variability, particularly a lower average ablation 
index (AI) required in women to achieve comparable clinical outcomes. 
This study aims to evaluate whether such sex-related anatomical differences translate into 
different ablation strategies, potentially supporting the development of individualized, sex-
specific ablation protocols. 
In addition, we aim to assess whether long-term clinical outcomes differ between sexes. 
 
2.2 Study Objectives 
2.2.1 Primary Objective: 
 
To compare long-term clinical outcomes of LAWT-guided atrial fibrillation ablation between 
male and female patients. 
 
2.2.2 Secondary Objectives: 
 
• 
To retrospectively compare mean LAWT, LAV, and inFAT between male and 
female patients undergoing their first ablation for PAF or PeAF. 
• 
To assess whether there are sex-based differences in the AI values used during AF 
ablation performed according to the BY-LAWT protocol. 
• 
To analyze the impact of sex on procedural parameters, including procedure time, 
total radiofrequency time, number of RF applications, early PV reconnection rates, 
and peri-procedural complications. 
• 
To evaluate the correlation between LAWT, LAV, inFAT, and the occurrence of 
procedural complications (particularly cardiac perforation/tamponade and PV 

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stenosis), stratified by sex. 
• 
To determine whether baseline differences in LAWT, LAV, and inFAT between 
sexes are independent predictors of long-term ablation success. 
 
3. METHODS 
3.1 STUDY DESIGN 
This is a retrospective, multicentric study, based on the analysis of already collected clinical 
and procedural data. 
3.2 STUDY SETTING 
The study will be conducted at Teknon Medical Center and at Pilar Medical Center., centers 
with proven experience in performing atrial fibrillation ablation. Electronic records of patients 
who underwent AF ablation will be reviewed. 
3.3 ELIGIBILITY CRITERIA 
Consecutive patients who underwent a first ablation procedure for paroxysmal or persistent 
atrial fibrillation at Teknon Medical Center and at El Pilar Hospital, starting from 01/01/2019 
to 31/03/2025. 
3.3.1 Inclusion Criteria: 
• 
Patients who underwent a first ablation procedure for atrial fibrillation (paroxysmal 
or persistent). 
• 
Availability of an adequate pre-procedural cardiac CT scan for LAWT, LAV and 
inFAT analysis. 

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• 
Availability of complete procedural data, including ablation index (AI) values 
recorded using the SmartTouch catheter (Biosense Webster). 
• 
Availability of 12-month follow-up data for efficacy and safety endpoint evaluation. 
• 
Ablation performed according to the by-LAWT protocol 
3.3.2 Exclusion Criteria: 
• 
Age < 18 years. 
• 
Previous cardiac ablation (including AF ablation or other arrhythmias). 
• 
Incomplete data regarding procedural parameters, or follow-up. 
• 
Poor quality pre-procedural cardiac MDCT 
• 
Ablation not performed according to the BY-LAWT protocol. 
• 
Structural heart disease (e.g., dilated cardiomyopathy, valvular heart disease with 
surgical indication) that could substantially influence atrial dimensions or ablation 
response. 
3.4 RETROSPECTIVE DATA COLLECTION 
Data will be extracted from electronic medical records of patients. All information will be 
anonymized before analysis. 
3.4.1 Pre-procedure CT scan (Existing data) 
Pre-procedural multidetector computed tomography (MDCT) images, previously 
acquired and already analyzed as per the inclusion criteria of the BY-LAWT protocol, 
will be retrieved from the institutional archive. 
 
3.4.2 Image Processing (Existing Data and New Analysis) 

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MDCT images will be analyzed (or re-analyzed, if necessary for uniformity) using 
ADAS-3D™ (Galgo Medical, Barcelona, Spain) to obtain 3D left atrial wall thickness 
maps and calculate left atrial volume. The analysis methodology will be consistent with 
what is described for a prospective study, ensuring the derivation of: 
• 
The endocardial layer defined by semi-automatic segmentation. 
• 
The epicardial layer defined by manual delineation with interpolation. 
• 
Calculation of wall thickness at each endocardial point as the distance between each 
endocardial point and its projection to the epicardial shell. 
• 
3D thickness map with a color scale. The color map uses a color scale to depict a 
range of thickness, as follows (right image): 
o < 1 mm: Red 
o 1-2.5 mm: Yellow 
o 2.5-3 mm: Green 
o 3-4 mm: Blu 
o > 4 mm: Purple 
• 
3D inFAT maps using a threshold-based segmentation of the volume between the 
endocardial and the epicardial LA shells previously obtained for 3D LAWT maps. 
InFAT will be defined as a tissue with reduced radiodensity, in the range of −194 
Hounsfield Units (HU) to −5 HU. Two specific inFAT subranges will be explored, 
the former between −194 HU and −50 HU (dense inFAT) and the latter between 
−50 HU and −5 HU (fat-myocardium admixture) 
• 
Calculation of left atrial volume (LAV) using ADAS-3D™ or standardized 
software. 

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3.5 STUDY ENDPOINTS 
Efficacy Correlation: 
The primary efficacy endpoint will be freedom from any atrial arrhythmia (AF, atrial 
tachycardia [AT], or atrial flutter [AFL]) at the 12-month follow-up. The following 
definitions apply: 
• 
AF recurrence will be considered only after the 3-month blanking period (see below), 
and defined as: 
o Patient-reported symptoms clearly suggestive of recurrence (e.g., rapid, 
recurrent palpitations with sudden onset and termination, lasting for several 
minutes or hours), 
o or AF documented on a 12-lead ECG, 
o or AF detected on a Holter monitor or device recording lasting >30 seconds. 
• 
The blanking period is defined as the first 3 months following the PVI procedure, during 
which a transient increase in atrial tachyarrhythmias may occur due to 
proarrhythmogenic inflammatory changes related to RF lesion formation. 
Sex-based differences in the primary endpoint will be analyzed. 
 
3.5.2 Secondary Endpoints 
• 
LAWT, inFAT, and LAV Differences: 
Comparison of mean left atrial wall thickness (LAWT), intramyocardial fat (inFAT) 
volumes and distribution, and left atrial volume (LAV) between male and female 
patients. 

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• 
Procedural Outcomes: 
Sex-based comparison of procedural characteristics, including delivered ablation 
index (AI), total procedure time, cumulative RF application time, number of RF 
applications, fluoroscopy time, first-pass pulmonary vein isolation rates, and incidence 
of early pulmonary vein reconnection. 
 
• 
Periprocedural Complications: 
 
Incidence of the following complications, extracted from patient records: 
o Death 
o Myocardial infarction 
o Diaphragmatic paralysis 
o Stroke or transient ischemic attack (TIA) 
o Other thromboembolic events 
o Cardiac perforation or tamponade 
o Vascular complications 
o Prolonged or repeated hospitalization 
o Heart block 
o Pulmonary vein (PV) stenosis >70% (as assessed by follow-up cardiac CT, if 
available) 
o Atrioesophageal fistula 
o Pericarditis requiring intervention 
o Pneumothorax 

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o Pulmonary edema 
 
3.6 VARIABLES TO BE COLLECTED 
Data will be collected retrospectively from clinical records and medical images. 
3.6.1 Baseline Data (at original patient enrollment) 
• 
Demographic data (age, sex, weight, height, BMI). 
• 
Medical and cardiovascular history (type of AF: paroxysmal/persistent, AF duration, 
cardiovascular risk factors, comorbidities, NYHA functional class, medications). 
• 
Transthoracic echocardiography (LA diameter, LVEF). 
• 
PV anatomy (anatomical variants). 
3.6.2 Procedural Data 
• 
Ablation catheter used (confirmation of SmartTouch Biosense). 
• 
Ablation parameters (RF power, mean and minimum contact force, mean ablation index 
(AI) per lesion, duration of RF applications). 
• 
Number of RF applications (total/per PVI RF line/per segment). 
• 
RF time (s), procedure time, fluoroscopy time. 
• 
First-pass isolation rates (and which veins). 
• 
Acute reconnections (and which veins/sites). 
• 
Acute peri-procedural complications. 
3.6.3 MDCT Variables of Wall Thickness and Atrial Volume (derived from re-
analysis or valid original analysis) 

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• 
Mean total LAWT (mm). 
• 
Mean total, dense inFAT and fat-myocardial admixture volumes (mL) 
• 
Mean LAWT of the PVI RF line (mm). 
• 
Mean total, dense inFAT and fat-myocardial admixture of the PVI RF line (mL) 
• 
Normalized LAWT of the PVI RF line (segment by segment, if possible). 
• 
Normalized total, dense inFAT and fat-myocardial admixture of the PVI RF line 
(segment by segment, if possible). 
• 
Left Atrial Volume (LAV) (ml). 
• 
Coefficient of variation of wall thickness in each segment (CV-WT) (segment by 
segment): standard deviation of wall thickness/mean LAWT. 
• 
Gaussian curvature (to get an idea of tissue heterogeneity). 
• 
Mean LAWT of reconnection points/segments (if identified). 
3.7 TIMELINE AND RECRUITMENT 
Given the retrospective nature of the study, no real-time patient recruitment will be performed. 
Data will be extracted from a pre-existing patient archive, covering the period from 01/01/2019 
to 31/03/2025. 
3.8 FOLLOW UP  
All patients routinely underwent clinical follow-up at 1, 3, 6, and 12 months after the index AF 
ablation. Therefore, follow-up data will be collected from clinical records, specifically 
assessing arrhythmia recurrence and the occurrence of late complications 
3.9 DATA MANAGEMENT 

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Data will be extracted anonymously into a secure electronic database, compliant with data 
privacy regulations (e.g., GDPR, if applicable). Access to data will be password-restricted to 
authorized investigators. Original paper medical records will remain in the center's archives. 
 
3.10 SAMPLE SIZE CALCULATION 
Given the retrospective design and the use of existing data, the sample size will be determined 
by the number of eligible patients identified in the medical records during the study period, 
from January 1, 2019, to May 31, 2025. 
 
3.11 STATISTICAL METHODS 
All analyses will be two-sided and performed using a significance level of 5% (α=0.05). 
• 
Continuous variables will be expressed as mean ± standard deviation (SD) or median 
(interquartile range) depending on their distribution (Shapiro-Wilk test). They will be 
compared using Student’s t-test or Mann-Whitney U test. 
• 
Categorical variables will be expressed as number (percentage) and compared with the 
chi-square test or Fisher’s exact test. 
• 
To compare LAWT, LAV and inFAT between men and women, appropriate statistical 
tests (e.g., independent t-test or ANOVA) will be used. 
• 
The efficacy endpoint (freedom from atrial arrhythmia at 12 months) will be analyzed 
using the Kaplan-Meier method, and curves will be compared with the log-rank test. 

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• 
Logistic or Cox proportional hazards regression models (for freedom from arrhythmia) 
will be used to identify independent predictors of ablation success, including sex, 
LAWT, LAV, inFAT and AI. 
 
3.11 PROTOCOL DEVIATIONS 
In a retrospective study, "protocol deviations" refer to cases where available data do not align 
with the inclusion/exclusion criteria or the planned data collection. Such cases will be 
documented and justified. 
3.12 HARMS 
There are no direct risks to patients associated with a retrospective study based on data review. 
Risks associated with the ablation procedure itself were addressed at the time of the original 
procedure 
 
4. ETHICS AND DISSEMINATION 
 
4.1 RESEARCH ETHICS APPROVAL 
This protocol must be reviewed and approved by the institutional review board (IRB) of Teknon 
Medical Center before data collection begins. A waiver of informed consent for retrospective 
collection of anonymized data will be requested, as patients will not be contacted directly. 

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Should the ethics committee require retrospective informed consent for data use, it will be 
obtained. 
 
4.2 CONFIDENTIALITY 
All study-related information will be stored securely at the study site. All participant data will 
be anonymized using a unique study ID number. Records containing personal identifiers will 
be kept separate from anonymized study data. All electronic databases will be password-
protected. Data confidentiality will be managed in compliance with applicable data privacy 
regulations. 
 
4.3 ACCESS TO DATA 
The principal investigators of the project will have direct access to the anonymized datasets. To 
ensure confidentiality, data distributed to project team members will be stripped of any 
participant identifying information. 
 
4.4 DISSEMINATION POLICY 
Study results will be disseminated through presentations at scientific conferences and 
publications in peer-reviewed journals. Results will be communicated in a way that does not 
permit the identification of individual patients. 

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APPENDIX 1: Data collection sheet for the byLAWT study 
 
Name: ………………………………………………. Medical Record No.: 
…………………………………. 
Date of Birth: …………………………………………… Study Code: ………………… 
Center: …………………………………. 
1. PATIENT DATA (AT THE TIME OF PROCEDURE): 
FIRST OPERATOR ………………… Anesthesiologist …………… EVALUATING 
OPERATOR ……………………… 
PROCEDURE DATE ...... /...... /...... 
AF Type: Paroxysmal // Persistent 
First AF diagnosis date: ...... /...... /...... 
Longest AF episode: <3 months / 3-6 months / 6-12 months / > 12 months 
Procedure: First AF Ablation (confirm) 
Age: ......... Sex: Male // Female CHA2DS2-VASc = .... HAS-BLED: … Weight ..... Kg 
Height: ...... m 
CVRF: none // HBP // Dyslipidemia // DM-2 // Smoker // OSA // Sport (>4 h/week x 10 
years) 
Underlying Heart Disease: none // Hypertensive // Ischemic // HOCM // Valvular // Other 
......................... 
Conduction Disturbances: none // LBBB // RBBB // LAHB // LPHB // Other: ................ 
Pharmacological Treatment (pre-ablation): .................................................... OAC: 
................................... 
Transthoracic Echocardiographic Data (most recent before procedure): LA Dimension (mm): 
........... LVEF: .......... Mitral Annulus: ………... cm Other: ………………………………… 
PV Anatomy (from CT/mapping report): 4 independent // Common left. // Common right // 
Accessory veins: .................................... 
2. PROCEDURAL DATA: 
Ablation Catheter Used (confirm SmartTouch Biosense): YES // NO (if NO, exclude patient) 

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Ablation Lines Adapted to "Fingerprinted" Esophagus: YES // NO (reason if NO: 
………………………………..) 
Catheter Curve (Smarttouch): Blue // Orange // Black 
Procedure Time: ............ min FAM + Merge Time: ………… min Transseptal Time: ………. 
min 
Transseptal Puncture Technique: Fluoroscopy // Fluid // TEE // Radiofrequency 
Fluoro Time: ......... sec Fluoro Dose: ……… mGy Fluoro Dose (index): …………..Gy/cm2 
RF Power: anterior wall ......... W // posterior wall ......... W 
RF Time: Right PV ......... s // Left PV ......... s 
Number of RF Points: Left PVs …… Right PVs…… 
First Pass Isolation (which veins): RSPV // RIPV // LSPV // LIPV 
Acute Reconnection after min 10’ waiting (which veins): RSPV // RIPV // LSPV // LIPV 
Intra-procedural Electrical Cardioversion: Yes // No 
Acute Peri-procedural Complications: 
………………………………………………………………. 
Was the procedure evaluated for the absence of gaps by the 2nd operator?: YES // NO 
3. MDCT VARIABLES OF WALL THICKNESS AND ATRIAL VOLUME (FROM ADAS-
3D™ ANALYSIS): 
CT Date: ...... /...... /...... 
Mean Total LAWT (mm): ……………………………… 
Mean total, dense inFAT and fat-myocardial admixture volumes (mL): 
…………………………… 
Mean LAWT of PVI RF Line (mm): ……………………………… 
Mean total, dense inFAT and fat-myocardial admixture volumes of PVI RF Line (mL): 
………… 
Normalized LAWT of PVI RF Line (segment by segment, if possible): 
……………………………… 
Normalized total, dense inFAT and fat-myocardial admixture of the PVI RF line (segment by 
segment, if possible): ……………………………… 

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Left Atrial Volume (LAV) (ml): ……………………………… 
Coefficient of Variation of Wall Thickness in Each Segment (CV-WT) (segment by segment): 
……………………………… 
Gaussian Curvature (mean for ablation areas): ……………………………… 
Mean LAWT of Reconnection Points/Segments (if identified): ……………………………… 
4. 12-MONTH FOLLOW-UP DATA (FROM PROCEDURE DATE): 
Last Follow-up Date: ...... /...... /...... 
Reported Arrhythmia Symptoms (at 3, 6, 12 months): Yes // No 
12-Lead ECG at 12 months: Sinus Rhythm // AF // AT // Atrial Flutter // Other: ……………. 
24-Hour Holter at 12 months: Sinus Rhythm // AF (>30s) // AT (>30s) // Atrial Flutter (>30s) 
// Other: ……………. 
Freedom from Any Atrial Arrhythmia at 12 Months (after blanking period): YES // NO 
Antiarrhythmic Medications (at 12th month): .................................................... 
Late Complications (e.g., PV stenosis >70% from subsequent CT, if performed): 
……………………………… 
Subsequent Re-ablation? Yes // No (Date and Reason: 
……………………………………………………) 
Other: ………………………………………………………………. 
 
 
 
 
 
 
 
 

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APPENDIX 2: Informed consent material 
 
 
1) PATIENT INFORMATION SHEET FOR A RESEARCH STUDY 
Study Title: Sex-Based Differences in Left Atrial anatomical characteristics: Impact on 
Atrial Fibrillation Ablation Outcomes – A Retrospective Multicenter Analysis  
Principal Investigator: Dr. Antonio Berruezo  
Research Center Address: Centro Médico Teknon  
Contact Phone Number: 932 90 62 00 
You are being asked to participate in a research study. First, we want you to know that your 
participation is completely voluntary. This consent document contains important information 
about the research study. Please read it carefully before deciding whether to participate. No one 
can force you to participate, and you can withdraw from the study at any time. If you agree to 
participate, you must sign this informed consent document. You will receive a signed copy for 
your records. This study has been reviewed and approved by the Hospital's Clinical Research 
Ethics Committee. 
1. WHAT IS THE PURPOSE OF THE STUDY? 
You are being asked to participate in this study because you have an abnormal heart rhythm 
called atrial fibrillation (AF). Radiofrequency ablation for AF is a procedure that uses a 
catheter to apply radiofrequency energy to the areas where the pulmonary veins connect to the 
left atrium. This electrically isolates these veins from the left atrium. This approach has been 
used for more than 20 years, since the origin of this arrhythmia was first described at the 
opening of the pulmonary veins into the left atrium. The efficacy of a single ablation procedure 
is approximately 75-80% at one year. In some cases, a second ablation procedure is required to 
isolate a point that may have reconnected one of the pulmonary veins to the atrium. 
The main objective of this study is to determine if procedures for effective electrical isolation 
of the pulmonary veins using the PeAF-by-LAWT protocol with the Thermocool SmartTouch® 
catheter (Biosense Webster, Inc., Irvine, CA, USA) show sex-based differences, considering 
existing anatomical characteristics, and whether they are at least as clinically effective 
(measured by atrial arrhythmia-free survival at 3, 6, and 12 months). 
2. WHAT ARE THE COMPLICATION RISKS OF THE STUDY? 
Since this is a retrospective study that analyzes existing data, there are no additional direct 
risks to you from your participation. All risks associated with your ablation procedure were 
explained to you and accepted at the time of your intervention. 
3. HOW IS THE STUDY DESIGNED? 

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This is a retrospective study. This means we will analyze existing information from your 
medical records and medical images (such as cardiac CT) related to your atrial fibrillation 
ablation. Your data will be anonymized to protect your privacy. 
4. WHAT ARE THE ALTERNATIVES TO PARTICIPATING IN THIS STUDY? 
Your decision to participate or not participate in this retrospective study will not affect your 
current or future medical care in any way. 
5. WHAT ARE THE POSSIBLE BENEFITS OF PARTICIPATING IN THIS STUDY? 
Although there are no direct benefits to you, your participation (through the anonymous use of 
your data) will contribute to the scientific understanding of sex-based anatomical differences 
in the left atrium and how these may influence the practice of atrial fibrillation ablation. This 
could lead to more personalized and safer treatments for future patients. 
6. IS PARTICIPATION IN THIS STUDY VOLUNTARY? 
Yes. Participation in this research study is voluntary. You may decide not to participate, and 
you can also change your mind later and withdraw from the study at any time without it 
affecting your clinical care. 
 
I, ______________________________________________________(Name and Surname) 
Have spoken with: 
__________________________________________________________________________ 
I have received sufficient information about why I am being asked to participate in the study. I 
have been able to ask questions about the study. I understand that my participation is voluntary. 
I understand that I can withdraw from the study at any time, without having to provide an 
explanation, and without it affecting my medical care. I consent to the collection and processing 
of my personal and medical data according to the specified conditions. And I have expressed 
my agreement to participate. 
PARTICIPANT: 
__________________________________       ____________   ________________________  
Participant's Signature                                                    Date                                  Time 
INVESTIGATOR: 
__________________________________       _____________________________________ 
Investigator's Signature                                                   Date                                  Time 
 

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2) PATIENT INFORMATION SHEET FOR THE RESEARCH STUDY 
Study Title: Sex-Based Differences in Left Atrial anatomical characteristics: Impact on 
Atrial Fibrillation Ablation Outcomes – A Retrospective Multicenter Analysis 
 Principal Investigator: Dr. Antonio Berruezo  
Research Center Address: Centro Médico Teknon  
Contact Phone Number: 932 90 62 00 
1. IF I PARTICIPATE IN THIS RESEARCH STUDY, HOW WILL MY PRIVACY BE 
PROTECTED? 
Access to your medical history and data from the procedure: The doctors, nurses, and other 
staff at the center involved in this study will need to access your medical history, including 
medical records and previous results, for the purposes of this study. By signing this consent 
form, you authorize this access and, if necessary, allow them to contact your general practitioner 
or other healthcare professionals to access your medical history during the study. In accordance 
with current data protection regulations, you expressly consent to the inclusion of your clinical 
data, as well as the data resulting from your participation in the study, in a personal data file 
under the responsibility of the Center. Access to your personal information will be restricted to 
the study doctor and their collaborators, health authorities, and the Research Ethics Committee. 
By signing this consent, you agree to the use of your anonymized data from the CT scan 
performed before the ablation. This data will be used to optimize the software for image post-
processing (ADAS-3DTM) and to develop a platform for the automation and standardization 
of this post-processing. Likewise, you consent to the use of anonymized data from the 
CARTO3TM navigation system and your clinical information by both the investigators at 
Centro Médico Teknon and the collaborating institutions (ADAS 3D Medical SL, Biosense 
Webster). 
Confidentiality of your health information: Your health information related to the trial will 
be included in a database, but you will not be identified by name in any report or publication. 
Withdrawal from the study: If you decide to withdraw from the study, please inform your 
study doctor. In this case, the study staff will not collect any new information about you. 
However, the information already collected may continue to be used as previously described. 
If you have any questions about this, we recommend that you speak with your study doctor. 
Compliance with current legislation on the confidentiality of your health information: The 
research team is committed to ensuring compliance with the principles established in Law 
14/2007 on Biomedical Research and Organic Law 3/2018, of December 5, on Personal Data 
Protection and Guarantee of Digital Rights. Furthermore, the research team is committed to 
facilitating your right to access, rectify, cancel, and oppose the use of your data, as provided 
for in Organic Law 3/2018 on Personal Data Protection and Guarantee of Digital Rights. The 
processing, communication, and transfer of participants' personal data will comply with the 
provisions of the European Data Protection Regulation (EU 2016/679). For any questions about 
the management of your data, you should contact the Centro Médico Teknon in Barcelona at 
C/Vilana, 12. 08022 Barcelona. In addition to the rights you are already aware of (access, 
modification, opposition, and cancellation of data), you can now also limit the processing of 

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data that is incorrect, request a copy, or have the data you provided for the study transferred to 
a third party (portability). To exercise your rights, please contact the principal investigator of 
the study. We remind you that data cannot be deleted, even if you stop participating in the study, 
to ensure the validity of the research and to comply with legal obligations and drug 
authorization requirements. You also have the right to contact the Data Protection Agency if 
you are not satisfied. 
2. WHO SHOULD I TALK TO ABOUT MY RIGHTS OR TO ASK QUESTIONS? 
Before signing this document, you should ask about anything you do not understand. The study 
team will answer your questions before, during, and after the study. If you feel your question 
has not been fully answered or if you do not understand the response, please keep asking until 
you are satisfied. If you have any concerns or complaints about this study or the way it is being 
conducted, please feel free to discuss them with the study team. The phone numbers to contact 
the study team are on the first page of this document. 
 
 

Sex-Tailored BY-LAWT AF-Ablation 
 
 
 
8 
REFERENCES 
 
 
1. 
2024 ESC Guidelines for the management of atrial fibrillation developed in 
collaboration with the European Association for Cardio-Thoracic Surgery (EACTS). 
European Heart Journal. 2024;45(36):3314–410. 
2. 
Duytschaever M, De Pooter J, Demolder A. Long-term impact of catheter ablation 
on arrhythmia burden in low-risk patients with paroxysmal atrial fibrillation: The CLOSE 
to CURE study. Heart Rhythm. 2020;17(4):535–43. 
3. 
Taghji P, El Haddad M, Phlips T, Wolf M, Knecht S, Vandekerckhove Y, et al. 
Evaluation of a Strategy Aiming to Enclose the Pulmonary Veins With Contiguous and 
Optimized Radiofrequency Lesions in Paroxysmal Atrial Fibrillation: A Pilot Study. JACC 
Clin Electrophysiol. 2018;4(1):99–108. 
4. 
Teres C, Soto-Iglesias D, Penela D, Jáuregui B, Ordoñez A, Chauca A, et al. 
Personalized paroxysmal atrial fibrillation ablation by tailoring ablation index to the left 
atrial wall thickness: the 'Ablate by-LAW' single-centre study-a pilot study. Europace. 
2022;24(3):390–9. 
5. 
Landra F, Saglietto A, Falasconi G, Penela D, Soto-Iglesias D, Curti E, et al. Left atrial 
intramyocardial fat at pulmonary vein reconnection sites during atrial fibrillation redo 
ablation. Europace. 2025;27(2). 
6. 
Fujimura T, Kishi T, Takamori A, Yamamoto T, Katagiri T, Kajiwara M, et al. Sex 
Differences in Patients with Atrial Fibrillation Undergoing Catheter Ablation. Int Heart J. 
2025;66(4):562–9. 
7. 
Tamirisa KP, Calvert P, Dye C, Mares AC, Gupta D, Al-Ahmad A, et al. Sex Differences 
in Atrial Fibrillation. Curr Cardiol Rep. 2023;25(9):1075–82. 
8. 
Yadav R, Milstein J, Blum J, Lazieh S, Yang V, Zhao X, et al. Sex-based differences in 
safety and efficacy of catheter ablation for atrial fibrillation. J Cardiovasc Electrophysiol. 
2023;34(8):1640–7. 
9. 
Lv H, Sun F, Fan Y, Tang B, Lu Y. Sex differences and risk factors for postoperative 
complications following catheter ablation for pulmonary vein isolation in non-valvular 
atrial 
fibrillation: 
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Medicine 
(Baltimore). 
2025;104(24):e42753.