Supplementation with omega-3 fatty acids and anti- oxidant vitamins may be considered to prevent post- operative AF after CABG, but additional clinical Kulik et al Secondary Prevention After CABG 949 studies are warranted before routine use of antioxi- dant vitamins can be recommended (Class IIb; Level of Evidence A). Vaccination Influenza is one of the most common, contagious, and mor- bid respiratory infections, with a seasonal pattern of affliction during winter climate.435 Among nontraditional risk factors, a growing interest has developed in the evaluation of influenza infection as a potential cause for subsequent cardiovascular Previous studies have suggested that seasonal influenza-like illnesses may explain the timing of acute throm- botic events in patients with CAD,438 and several epidemio- logical studies have identified an inverse relationship between influenza vaccination and the risk of fatal and nonfatal cardio- Although the mechanism underlying that risk of influenza is not clear, it may relate to triggering the rupture of a vulnerable atherosclerotic plaque, fluid overload, and heart failure or to the susceptibility of a frail and vulner- Randomized, controlled trials have since been performed to explicitly test whether influenza vaccination can reduce the risk of cardiovascular events. In one of the first trials on the subject, Gurfinkel et al443,444 randomized 200 patients with MI and 101 patients undergoing elective percutaneous coronary intervention to either multivalent influenza vaccine or pla- cebo. At 1 year of follow-up, the risk of MI and cardiovascu- lar death was significantly lower among patients who received the vaccine. 