[Multicenter study of atrial fibrillation].

Area of Science:

• Cardiology
• Electrophysiology
• Internal Medicine

Background:

• Atrial fibrillation (AF) is a common arrhythmia with significant morbidity and mortality.
• Understanding the etiology and effective treatment strategies for a first episode of AF is crucial.

Purpose of the Study:

• To analyze the characteristics, etiologies, and outcomes of patients experiencing their first episode of atrial fibrillation.
• To compare the effectiveness of electrical versus pharmacological cardioversion for AF reduction.
• To identify predictors of successful AF reduction.

Main Methods:

• Retrospective analysis of 1134 patients with a first episode of atrial fibrillation (AF) from January 1985 to December 2000.
• Data collected included patient demographics, AF etiology, treatment methods (electrical and pharmacological cardioversion), and survival rates.
• Statistical analysis to compare outcomes between AF and sinus rhythm groups and to identify predictors of AF reduction success.

Main Results:

• Rheumatic carditis (36.1%) and idiopathic causes (27.7%) were the leading etiologies of AF.
• Patients with AF had significantly higher morbi-mortality and lower five-year survival (85%) compared to sinus rhythm (96%).
• Electrical cardioversion achieved a 70% success rate, significantly higher than pharmacological cardioversion (40%).
• Left atrial diameter did not predict AF reduction success, but longer duration of AF was associated with treatment failure.

Conclusions:

• First episode atrial fibrillation, particularly due to rheumatic carditis, is associated with increased mortality.
• Electrical cardioversion is a more effective strategy for AF reduction compared to pharmacological approaches.
• The duration of atrial fibrillation is a key factor predicting the failure of cardioversion therapies.