The goal of this observational study is to evaluate cardiac stunning and electrocardiographic parameters through transthoracic echocardiography and 24 hours ECG conducted immediately following electrical cardioversion. The main question it aims to answer is:

Do echocardiographic and electrocardiographic parameters relating to cardiac stunning predict atrial fibrillation (AF) recurrence rates after electrical cardioversion?

Participants will undergo echocardiography and a 24-hour Holter monitoring immediately after electrical cardioversion.

Inclusion Criteria:

• Patients with atrial fibrillation
• Patients with persistent or symptomatic atrial fibrillation who are candidates for electrical cardioversion
• Patients eligible for anticoagulation therapy for thromboembolism prevention before and after the procedure
• Patients who can understand and provide written informed consent

Exclusion Criteria:

• Patients under 18 years of age or over 80 years of age
• Patients who do not consent to participate in the study
• Patients with severe coronary artery stenosis
• Patients with severe hepatic dysfunction
• Patients with severe renal dysfunction
• Patients with severe valvular heart disease
• Patients with a high risk of severe bleeding
• Patients with a history of atrial fibrillation-related catheter ablation or cardiac surgery
• Patients with an expected life expectancy of less than 1 year
• Potentially pregnant individuals
• Patients deemed unsuitable for the study by the investigator

Korea University College of Medicine, Guro Hospital