Evaluation of Two Different Regimens of the Antiarrhythmic Drug Amiodarone to Maintain Normal Sinus Rhythm After Electrical Cardioversion in Patients With Persistent Atrial Fibrillation

Inclusion Criteria 1. Patients aged ≥ 18 years 2. Documented persistent atrial fibrillation (≥ 7 days in duration) 3. Electively referred for Electrical Cardioversion 4. Signed informed consent. Exclusion Criteria 1. Urgent electrical cardioversion 2. Atrial fibrillation post-cardiac surgery 3. Previous myocardial infarction 4. New York Heart Association (NYHA) Class IV heart failure 5. Left ventricular ejection fraction (LVEF) \<45% 6. Significant left ventricular hypertrophy (wall thickness ≥ 15mm) 7. Hyperthyroidism or hypothyroidism 8. Known hepatobiliary disease (acute hepatitis, cirrhosis...) or ALT/AST \> 3 x upper limit of normal (ULN) 9. Allergy, intolerance, or known hypersensitivity to study medications 10. Women of childbearing potential unwilling to use contraceptive measures and breastfeeding women. 11. Participation in another clinical trial involving investigational drugs 12. Life expectancy less than 12 months 13. Rheumatic mitral stenosis of any degree or severe mitral or aortic valve dysfunction. 14. Patients with contraindications to amiodarone, such as uncontrolled thyroid dysfunction, severe sinus bradycardia, second- or third-degree AV block without a pacemaker, and a history of amiodarone-induced pulmonary toxicity. 15. Patients in whom chronic amiodarone treatment previously failed to maintain sinus rhythm 16. Patients with abnormal baseline QTc (\>450 ms in males and \>470 in females) or abnormal ECG that precludes QTc assessment 17. Patients requiring concomitant medications that have a higher risk of QTc prolongation. 18. Patient do not have a smart mobile phone or do not know how to use it adequately.