The hypothesis implies that this work is the use of hyperoxia during cardiopulmonary bypass by his heart preconditioning effect is associated with a lower incidence of cardiac arrhythmias (atrial fibrillation, tachycardia or ventricular fibrillation) and lesions of myocardial ischemia-reperfusion injury in cardiac surgery postoperative.

Inclusion Criteria:

• Major patient ≥ 18 years
• Patient operated cardiac surgery for myocardial revascularization (CABG) or surgical correction of valvular or combined surgery (CABG and valve disease) or ascending aortic surgery
• Signed Consent
• Affiliation to social security

Exclusion Criteria:

• Permanent atrial fibrillation
• Cordarone therapy,
• Pregnant woman
• Patient under guardianship or trusteeship or private public law
• Internal pacemaker
• Hypothermia,
• Patient refusal,
• Cardiac surgery without extracorporal circulation (ECC),
• Participation in another study.