Assessment of Atrial Cardiomyopathy Using MRI as a Predictor of Cardiac Post-Operative Atrial Fibrillation After Cardiac Surgery.

Cardiac magnetic resonance imaging (MRI) will be realized before Coronary Artery Bypass Grafting for assess atrial cardiomyopathy.

Blood sample will be realized (4 tubes of 4ml blood, 16ml in total) before Coronary Artery Bypass Grafting.

Cardiac muscle biopsy will be realized during Coronary Artery Bypass Grafting.

Holter-electrocardiogram (ECG) will be realized 1 year after Coronary Artery Bypass Graftin during 3 days to diagnose the occurrence of atrial fibrillation.

medical examination will be realized 1 year after Coronary Artery Bypass Graftin. Theses datas will collected: events during the follow-up year and evaluation of the Holter-electrocardiogram result.