ROME, ITALY. Atrial fibrillation is a common complication of coronary artery bypass graft surgery. Treatment with beta-blockers, sotalol or amiodarone can reduce the risk of AF development somewhat, but these drugs have several undesirable side effects. Italian researchers now report that fish oil supplementation is highly effective in preventing post-operative atrial fibrillation. Their randomized clinical trial involved 160 patients (136 men and 24 women) scheduled for elective bypass surgery. The average age of the patients was 66 years and one of them had a previous history of AF. Half the patients were randomized to receive 2 grams/day of ethyl esters of EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) for at least 5 days prior to their operation and for the remainder of their hospital stay. The other half just received usual post-operative care.
All patients underwent continuous rhythm monitoring for the first 4 to 5 days after surgery. During this monitoring period, 27 patients in the control group (33%) experienced afib episodes lasting an average of 24 hours. In contrast, only 12 patients in the fish oil group (15%) experienced episodes and they lasted an average of only 15 hours. Non-fatal post-operative complications occurred in 7 patients in the control group and in 5 patients in the fish oil group; 2 patients died after the operation in the control group versus 1 patient in the fish oil group.
The researchers speculate that the beneficial effects of fish oil are associated with its documented ability to reduce inflammation as well as with its direct effect on cardiac myocytes (muscle cells), specifically in regard to resting membrane potential and an increase in phase 4 refractory period. They conclude that fish oil supplementation can safely be administered to all patients undergoing bypass surgery and that it is at least as effective as medication with beta-blockers, sotalol or amiodarone.
Calo, L, et al. N-3 fatty acids for the prevention of atrial fibrillation after coronary artery bypass surgery. Journal of the American College of Cardiology, Vol. 45, May 17, 2005, pp. 1723-28