Dose Ranging Study of Dronedarone for the Control of Ventricular Rate in Japanese Patients With Permanent Atrial Fibrillation

Inclusion criteria: * Patients of aged 20 years or more. * Permanent Atrial Fibrillation \[AF\] (defined as duration of AF \> 6 months) for which cardioversion is not considered and with resting ventricular heart rate ≥ 80 bpm at screening. Exclusion criteria: * Unstable angina pectoris. * History of torsades de pointes. * Prolonged QT corrected interval (≥ 500 ms). * Third degree atrioventricular block (AVB) on the screening ECG while in AF or, documentation on previous ECGs while in sinus rhythm of PR-interval \> 0.28 sec or high degree AVB (2nd degree or higher) or, significant sinus node disease (documented pause ≥ 3 sec) - without a permanent pacemaker implanted. * Congestive Heart Failure (CHF) of New York Heart Association classification (NYHA) class IV or recent (within 1 month prior to randomization) unstable NYHA class III. * Treatment with other class I or III anti-arrhythmic drugs. * Patients treated with amiodarone during the 4 weeks preceding randomization. * Clinically relevant haematologic, hepatic, gastro-intestinal, renal, pulmonary, endocrinologic (in particular thyroid) or psychiatric disease. * Hypokalemia and hypomagnesemia must be corrected before randomization. The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.