Short-Term Fish Oil Use Doesn't Quell Irregular Heart Rhythm After Heart Surgery

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Study Highlights:

  • Short-term fish oil supplementation didn't prevent irregular heart rhythm after heart surgery.
  • However, supplementation didn't cause any health-related drawbacks either.
  • Researchers say further research should examine longer-term effects of fish oil supplements.

LOS ANGELES, Nov. 5, 2012 (GLOBE NEWSWIRE) -- Short-term fish oil supplementation doesn't decrease irregular heart rhythm that commonly occurs after patients have heart surgery, according to late-breaking clinical trial results presented at the American Heart Association's Scientific Sessions 2012.

The full manuscript for the Omega-3 Fatty Acids for Prevention of Post-Operative Atrial Fibrillation (OPERA) trial is published in the Journal of the American Medical Association.

Atrial fibrillation — a fluttering of the heart's two upper chambers — occurs after heart surgery in about a third of patients and can cause a stroke.

Studies have suggested that eating fish regularly or supplementing with fish oil might lower atrial fibrillation risk.

Researchers in the United States, Argentina and Italy studied 1,516 patients (average age 64 years) undergoing heart surgery. Patients received either a placebo supplement or supplements containing 8 to 10 grams of omega-3 polyunsaturated fatty acids during the two to five days before surgery and 2 grams daily for 10 days after surgery.

Researchers found:

  • Most cases of atrial fibrillation occurred between one and four days after surgery, peaking on day two.
  • Post-operative atrial fibrillation occurred in 233 patients (30.7 percent) in the placebo group and 227 patients (30 percent) in the group who took fish oil.
  • No differences between the groups in the numbers of heart attacks or stoke occurred while patients recovered in the hospital after surgery.
  • There were no differences in death 30 days after surgery or number of days in the intensive care unit after surgery.

Fish oil supplementation was safe in these surgical patients and didn't cause any health-related drawbacks, such as increased bleeding risk, the researchers said.

"Omega-3 polyunsaturated fatty acids may offer a number of protective effects to prevent cardiovascular disease," said Dariush Mozaffarian, M.D., Dr.P.H, co-author of the study and associate professor of medicine in the Harvard Medical School in Boston, Mass. "But if you look at this particular population of surgical patients and short-term use, fish oil does not help avoid atrial fibrillation.

Further research should examine whether long-term fish oil consumption helps prevent atrial fibrillation in elderly adults with high blood pressure and other heart disease risk factors, said Roberto Marchioli, M.D., study co-author and head of the Laboratory of Clinical Epidemiology of Cardiovascular Disease, Consorzio Mario Negri Sud in Santa Maria Imbaro, Italy.

Other co-authors are Alejandro Macchia, M.D.; Maria G. Silletta, M.P.H.; Paolo Ferrazzi, M.D.; Timothy J. Gardner, M.D.; Roberto Latini, M.D.; Peter Libby, M.D.; Federico Lombardi, M.D.; Patrick T. O'Gara, M.D.; Richard L. Page, M.D.; Luigi Tavazzi, M.D.; and Gianni Tognoni, M.D.

The National Heart, Lung, and Blood Institute, GlaxoSmithKline, Sigma Tau and Pronova BioPharma funded the study.

Disclosures are here

Find out more about fish and omega-3 fatty acids at the American Heart Association's Nutrition Center.

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Note: The OPERA presentation is 9:19 a.m. PT, Monday, Nov. 5, in Petree Hall D. - Embargo time corresponds with JAMA publication.

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Source:American Heart Association