Effect of Pre-surgical Supplementation with Omega-3 on Outcomes after Heart Surgery
Farquarharson , A. L. et al., American Journal of Cardiology , 108: 851-856 , 2011
Discipline of Medicine, University of Adelaide and Dept. of Cardiology, Royal Adelaide Hospital, Adelaide, Australia
Atrial fibrillation is a relatively common heart rhythm disorder which often occurs as a result of cardiac surgery. It is associated with extended stays in the intensive care unit (ICU) and the overall duration of hospitalization as well as increased mortality. Since an anti-arrhythmic effect of EPA/DHA omega-3 fatty acids has been indicated in multiple animal and some human studies, the present investigation was conducted to evaluate the potential beneficial effects of supplementation with omega-3 prior to cardiac surgery on the post-surgical outcomes. Patients (200) scheduled for coronary artery bypass surgery (CABG) or valve repair were randomly assigned to receive a placebo capsule lacking omega-3 (control group) or 2.7 gm EPA plus 1.9 gm DHA daily for 21 days prior to surgery. Supplementation was maintained for 6 days after surgery or until discharge from hospital (whichever came first).
The overall incidence of in-hospital atrial fibrillation (AF) was found to be 48 % for the control group and 37 % in those given EPA/DHA with no statistically-significant difference between the two groups. A trend for a delayed time to occurrence of AF (by 29-34 %) was found in the omega-3 group as compared to controls which did not quite reach statistical significance. A statistically-significant lesser period of time in the ICU post-surgery was found for patients previously given omega-3 (average of 67 hours) as compared to those in the control group (average of 95 hours). The omega-3 group also showed much higher levels of omega-3 in samples of cardiac tissue when taken at the time of surgery for fatty acid analyses (EPA plus DHA averaged at 8.14 % of total fatty acids in heart tissue phospholipid for the omega-3 group as compared to only 4.94 % for the controls). The authors concluded that the lessened period of time spent in the ICU following cardiac surgery resulting from the pre-surgical supplementation with EPA/DHA is likely to be significant for health costs because of the high costs associated with intensive care.
It is of interest to note that, despite the fact that the omega-3 supplementation contained much more EPA than DHA, the DHA levels in the heart tissue samples (analyzed in the phospholipid fraction) from the omega-3 patients had three times more DHA than EPA (6.10 % as DHA and only 2.03 % as EPA). It is possible that the beneficial effects seen with omega-3 supplementation could be mediated more by the enrichment of DHA in cardiac tissue. However, multiple factors over and above decreased AF due to omega-3 enrichment in cardiac tissue could likely be responsible for the reduced time of patients in the ICU following surgery. The various benefits of omega-3 which are external to their accumulation in cardiac tissue might be due to cellular accumulations of EPA and/or DHA and the formations of their bio-active metabolites (eg, anti-inflammatory resolvins , protectins , other products).