ALA is administered orally since it is without difficulty absorbed in the stomach. ALA goes through the blood brain barrier and does not show toxic effects and actions at doses used for prophylactic and therapeutic purposes. This has encouraged us to use an efficient anti-oxidant and anti-inflammatory agent, alpha-lipoic acid (biochemical) as a relevant option to prevent POAF.

Investigators computed on the basis of findings from a prior study found the incidence of POAF after cardiac surgery of about 25% . Assuming a slightly lower alpha-lipoic acid' effect to previous study. If the true relative risk of AF for experimental subjects relative to controls is 0.5 , with α equivalent to 0.5 and power (1 - β) is 0.8, the estimated sample size is 152 experimental subjects and 152 control subjects in order to be able to reject the null hypothesis that this relative risk equals 1 with probability (power) of 0.8. investigators used the uncorrected chi-squared statistics to evaluate this null hypothesis. STATA software version and taking into account a possible dropout of 15%, the total sample size was: 304 + 0.15 (304) × 2 = 350 subjects of which there will be 175 controls and 175 experimental subjects %, assuming an enrolment ratio of 1:1.

Inclusion Criteria:

• I
• Male or female patients above 18 years of age who are scheduled for cardiac surgery.

Exclusion Criteria:

• Any urgent or emergency surgery.
• Poor Left ejection volume (EF < 30%).
• Intake of steroids or any antiarrhythmic drugs except beta blockers during the last month before surgery
• Unable or unwilling to provide informed written consent.
• Pregnancy or lactation
• Known hypersensitivity to the study drug.
• Current treatment with antioxidants or alpha-lipoic acid for any indication.
• Infection or inflammatory disease except coronary artery disease.
• Left atrium size >70 mm.