The prevalence of atrial fibrillation (AF) is on the rise, being the most frequent sustained
supraventricular arrhythmia and a health issue by its increased morbidity and mortality. In
most of the cases, myocardial tissue located at the level of the pulmonary veins represents
the trigger for atrial fibrillation. The pathophysiology of AF is still incompletely
understood, several studies suggesting that profibrotic and inflammatory processes have a
crucial role in the development of AF. So far the success rate of AF ablation is not very
high, reaching 70% in patients with paroxysmal AF and 50% in cases with persistent AF.
Several risk factors for the occurrence and recurrence of AF have been described in the
literature, including left atrial enlargement, left ventricular dysfunction, epicardial fat
volume, and myocardial fibrosis caused by local atrial inflammation. What remains to be
investigated is the relationship between these risk factors and the recurrence of AF after
radiofrequency catheter ablation using advanced 3D mapping system.
This is a clinical prospective, descriptive, single-center study which will be carried out in
the Center of Advanced Research in Multimodal Cardiac Imaging Cardiomed Tirgu Mures, Romania.
The duration of the study is 2 years which include the initial screening and the follow-up
period for the recurrence of AF.
The study will include 100 subjects suitable for catheter ablation. Imaging biomarkers and
laboratory analyses such as high sensitive C Reactive Protein (hsCRP), matrix
metalloproteases (MMP), interleukin-6 (IL6) and N-Terminal Pro-B-Type Natriuretic Peptide (NT
pro-BNP) will be determined in the first 24 hours after the procedure. The anatomy of
pulmonary veins, atrial fibrosis, atrial volumes and the amount of epicardial fat will be
evaluated and quantified with late gadolinium-enhancement cardiac magnetic resonance
(LGE-CMR). All these parameters will be investigated in patients with successful ablation of
AF, who will be divided into 2 groups: group 1 - patients who develop AF recurrence at
1-year, and group 2 - patients with no recurrence of AF at 1-year. In all patients, the
following biomarkers will be determined: serum levels of inflammatory biomarkers and
NT-proBNP at 24 hours and 1 year post-procedure, the amount of myocardial fibrosis at the
level of left atrium and left ventricle at baseline +/- 7 days and the amount of epicardial
fat surrounding left atrium, right atrium and the entire heart at baseline +/- 7 days.
The study will be conducted over a period of 2 years, in which patients will be examined at
baseline, and will be followed-up for recurrence of AF.
All patients will sign an informed written consent and will be checked for the exclusion
criteria prior to enrolment.
Study objectives:
Primary: To investigate the correlation between imaging markers provided by cardiac magnetic
resonance (including the degree of left atrial and ventricular fibrosis, left and right
atrial volume, epicardial fat tissue volume), inflammatory biomarkers, and the risk of AF
recurrence post ablation.
Secondary: To investigate the correlation between structural remodeling of the left and right
atrium, epicardial fat tissue volume and serum inflammatory biomarkers in patients with AF.
Study Timeline:
Baseline (day 0)
Obtain and document consent from participant on study consent form.
Verify inclusion/exclusion criteria.
Obtain demographic information, medical history, medication history, alcohol, and
tobacco use history.
Record results of physical examinations and 12-lead ECG.
Collect blood specimens (complete blood count, biochemistry and inflammatory
biomarkers).
Imaging procedures: transthoracic 2-D echocardiography, late gadolinium-enhancement
cardiac magnetic resonance
Visit 1 (month 1,3,6,12)
Record results of physical examinations, 12-lead ECG and medical history.
Imaging procedures: transthoracic 2-D echocardiography
Final study visit (month 12)
Record results of physical examinations, medical history,12-lead ECG and determination
of serum levels of inflammatory biomarkers and NT-proBNP
Imaging procedures: transthoracic 2-D echocardiography
End-point evaluation.
Study procedures:
Medical history, clinical examination, laboratory tests (complete blood count,
biochemistry, serum level of hs-CRP, MMP, IL6, and NT-pro-BNP);
12-lead ECG
2D transthoracic echocardiography with measurement of cardiac diameters, volumes,
valvular function and regurgitation, pressure gradients, left ventricular systolic and
diastolic function and ejection fraction.
Late Gadolinium-Enhancement Cardiac Magnetic Resonance (LGE-CMR) with the evaluation of
left and right atrial volume, the volume of epicardial adipose tissue, the degree of
atrial and ventricular fibrosis
Pulmonary vein isolation radiofrequency ablation with advanced 3D mapping system
Data collection: All the information will be collected in a database that consists of
patient's background, medical history, medication, imaging features provided by cardiac
ultrasound, Cardiac magnetic resonance and CMR imaging post-processing.
