A large body of evidence has accumulated showing that n-3 PUFAs exert extensive cardiac effects. The development of commercial solutions of FO opens perspectives for therapeutic applications in patients with acute cardiac conditions.the 3 following hypotheses will be addressed in patients requiring cardiac surgery under cardiopulmonary bypass or after myocardial infarction:perioperative /post-PTCA intravenous fish oil modifies the composition of membrane phospholipids in platelets and cardiac cells, blunts the physiological response to cardiac surgery/myocardial infarction, and reduces the incidence of arrhythmias, and reduces the occurrence of systolic dysfunction.

A. Randomized trial in 40 cardiac surgery patients Early rapid infusion of fish oil (3 times in 24 hours) in cardiac surgery patients.

B. Randomized trial 20 myocardial infarction patients (abandonned) Continuous infusion of the same dose over 24hrs in the myocardial infarction patients

Additional trial in healthy volunteers (investigating physiological changes after cardiac study):

-Open trial in 8 healthy lean volunteers to investigate the impact of the same 0.6 g/kg FO dose IV (Week 1: 3hrs), and then orally on week 2, on platelet n-3 PUFA incorporation, platelet function, heart rate and peak flow response to stress test.

Inclusion Criteria:

• Coronary artery disease requiring elective surgical repair under cardiopulmonary bypass
• Acute myocardial infarction requiring ICU management

Exclusion Criteria:

• Absence of consent
• Ventricular ejection fraction < 35%
• Beating heart surgery or emergency surgery
• Hypercholesterolemia > 5 mmol/l
• Thrombolysis
• Chronic steroid therapy
• Acute or chronic renal failure prior to surgery (plasma creatinine > 150 umol/l)
• Chronic coagulation disorder
• Premenopausal female
• Consumption of more than 3 times fish per week