Atrial Fibrillation Ablation
Condition: Atrial Fibrillation; Heart Failure, Diastolic
MeSH terms: Atrial Fibrillation; Heart Failure, Diastolic
Study type: Interventional

Summary: 
      Objective. Atrial fibrillation (AF) recurrence after catheter ablation (CA) is a relevant
      clinical problem.

      Methods. 123 patients with paroxysmal AF will be identified and screened for participation in
      this randomized, prospective, double blind, controlled placebo multicenter trial. 109
      patients will be randomly assigned and enrolled in the study trial. Enrolled patients will
      receive magnetic atrial resonance and then will be treated by CA to receive pulmonary vein
      isolation (PVI). In this patients cytokines, inflammatory markers, and biomarkers such as ST2
      protein and B type natriuretic peptide (BNP) will be evaluated at baseline, after CA, and
      during follow up. These biomarkers will be correlated to clinical outcomes (AF recurrences
      and heart failure progression and hospitalizations), and to fibrotic atrium extension as
      evaluated by magnetic resonance.
    

Detailed description: 
      Catheter ablation (CA) is first class treatment to restore sinus rhythm in patients with
      paroxysmal, symptomatic, drug refractory atrial fibrillation (AF). The sinus rhythm
      restoration after a successful CA may improve symptoms, New York Heart Association (NYHA)
      class and quality of life, reducing thromboembolic complications, and the likely progression
      of the arrhythmic disease towards forms of heart failure. Conversely, patients that do not
      respond successfully to CA therapy may still have AF, that is linked to an increased risk of
      ischemic stroke, heart failure, and overall mortality. AF recurrence after CA occurs in a
      percentage of patients ranging from 20% to 60%. This high rate of therapeutic failure, and
      the higher number of patients suffering for paroxysmal AF, represent a not acceptable problem
      in the clinical practice. The causes to explain this therapeutic failure are not completely
      clear, and broadly investigated by authors. To date, hyper activity of inflammatory tone, and
      oxidative stress with secondary left atrium enlargement and fibrosis, may represent a crucial
      part of molecular, and cellular adaptive processes linked to electro-anatomical remodeling,
      and to the AF perpetuation after an ablative treatment. Intriguingly, if the atrial fibrosis
      extension is a known process linked to worse prognosis, conversely the ablative approach
      therapy by burning to destroy arrhythmic cells, may also induce inflammation and atrial
      fibrotic lines around the veins' ostia. Therefore, the double face of the coin shows to the
      investigators the atrial fibrosis as an adaptive remodeling process linked to worse
      prognosis, and the atrial fibrosis as the result of a correct ablative approach to isolate
      pulmonary veins ostia and to improve clinical outcomes. To simply the concept, authors have
      to consider the first as an adaptive process leading to worse prognosis in AF patients, and
      the second as a necessary treatment to improve clinical outcomes in AF patients. Different
      studies have investigated cytokines, inflammatory markers, and other peptides such as B type
      natriuretic peptide (BNP), before and after CA in paroxysmal AF patients. These markers, and
      particularly BNP are correlated to atrial fibrosis extension, and worse prognosis after an
      ablative approach, and to the progression towards failing heart disease. Recently, the ST2
      protein has been proposed as a new marker of heart fibrosis, such as a predictor of heart
      failure. Currently, no data has been reported about ST2 protein and AF recurrences after an
      ablative approach. Moreover, in the current study authors will investigate at baseline, and
      at follow up after an ablative approach, the using of cytokines, inflammatory markers, and
      other peptides such as B type natriuretic peptide (BNP), and ST2 protein, regards to these
      adaptive atrial fibrotic processes, and to AF recurrences after catheter ablation. Therefore,
      in this study authors will evaluate these biomarkers in patients with symptomatic and drug
      refractory paroxysmal AF undergoing catheter ablation interventions, and their correlation to
      AF recurrence rate after catheter ablation. To date, in the present study authors will
      correlate these biomarkers, and particularly ST2 protein to AF recurrences after CA, to left
      atrium fibrotic remodeling, and to hospitalizations events for heart failure at 12 months
      follow up.
    

Intervention name(s): trans cateheter ablation
Intervention type(s): Procedure
Intervention description(s): All AF patients will receive trans catheter ablation by radiofrequency, to destroy arrhythmic atrial cells, and to isolate arrhythmic atrial firing around pulmonary veins' ostia.
Other intervention name(s): magnetic resonance of left atrium
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Basic Science