Dose-ranging Phase II study testing the efficacy and safety of 3 doses of Ranolazine (low, intermediate and high, given BID) versus placebo in maintaining sinus rhythm after successful electrical cardioversion in patients with persistent atrial fibrillation (AFib).

After successful cardioversion and subsequent randomisation, patients report trans-telephonic EGCs on a daily basis to a central core ECG facility.

Maximum treatment duration is 112 days (16 weeks).

Patients with persistent AFib are screened for eligibility and undergo direct current cardioversion (DCC). If DCC is successful (defined as persistence of sinus rhythm 2 h post-DCC) patients meeting all the inclusion criteria and none of the exclusion criteria are randomly assigned to the treatment arms (Ranolazine low, intermediate, high dose or placebo, given BID).

Transtelephonic ECG devices (TT-ECG) are used for recording of AFib recurrence to be read by a Central ECG Core Laboratory. Any symptoms indicative of AFib have to be recorded by the patient in a diary.

Study Visits are held for screening (Visit 1), at DCC and randomisation (Visit 2), one week post DCC (Visit 3), after 8 weeks of treatment (Visit 4), and at end of treatment (Visit 5). A safety follow-up telephone call is held 2 weeks after end of treatment.

12-Lead ECGs are performed at every visit.

Safety evaluations include regular safety laboratory blood and urine tests, 12-lead ECGs and the continuous recording of adverse events.

A double-dummy technique is used to ensure double-blind conditions.

Inclusion Criteria:

• Male or female patients 18 years and older
• Patients with persistent AF suitable for electrical direct current cardioversion (DCC)
• A female of childbearing potential may be enrolled providing she has a negative pregnancy test at baseline and is routinely using an effective method of birth control resulting in a low failure rate until end of study
• Able to give written informed consent before any study related procedure
• Able to attend all the visits scheduled in the study

Exclusion Criteria:

• Patients with first diagnosed AF or patients with paroxysmal AF
• Patients with long-standing persistent AF or permanent AF
• Patients having known concurrent temporary secondary causes of AF such as alcohol intoxication, pulmonary embolism, hyperthyroidism, pneumonia, hypoxemia, acute pericarditis or myocarditis
• Patients having undergone atrial catheter ablation for AF
• Patients carrying a pacemaker
• Patients with electrolytes imbalances that may cause cardiac arrhythmias, e.g. potassium < 3.5 mmol/L or > 5.5 mmol/L
• Patients with any contra-indications to Ranexa according to the drug-specific product characteristics
• Patients taking class I or Class III antiarrhythmic agents within 3 days of planned randomisation
• Patients taking beta-blockers unless used on stable doses for at least 2 weeks prior to the planned randomisation. Single doses of Intravenous beta-blockers are allowed up to 10 hours from the planned randomisation
• Patients taking Dronedarone or oral Amiodarone within 2 weeks and 3 months of planned randomisation, respectively
• Patients with a history of ECG abnormalities that in the opinion of the Investigator render the subject unsuitable for the trial, including history of congenital or a family history of long QT syndrome and a QTc interval ≥500 msec at Screening
• Patients with congestive heart failure NYHA grade III and IV;
• Patients with any serious intercurrent illness (including psychiatric and neurological disorders) which, in the opinion of the Investigator, is incompatible with the protocol.
• Patients taking Metformin at a total daily dose greater than 1000 mg.
• Patients taking Simvastatin at a total daily dose greater than 20 mg.

ITT-population (excluding 3 randomized patients who never started study drug)

16 weeks (112 days)

Most of the Kaplan-Meier estimates could not be calculated due to the lower than expected number of observed events and the high variability of data.