Save Your Money: Fish Oil and Postoperative Atrial Fibrillation
To save some of our hard-earned tax payers’ money, this is an ideal study to be performed as a point-of-care clinical trial using the electronic health record. After providing informed consent, give the drug order to the hospital pharmacy and get the outcome data at time of discharge directly from the EHR.
Postoperative atrial fibrillation or flutter (AF) is one of the most common complications of cardiac surgery and significantly increases morbidity and health care utilization. A few small trials have evaluated whether long-chain n-3-polyunsaturated fatty acids (PUFAs) reduce postoperative AF, with mixed results. As a result, a study reported in the Journal of the American Medical Association (2012;308:2001-2011), was performed to determine whether perioperative n-3-PUFA supplementation reduces postoperative AF.
The Omega-3 Fatty Acids for Prevention of Post-operative Atrial Fibrillation (OPERA) double-blind, placebo-controlled, randomized clinical trial, included a total of 1,516 patients scheduled for cardiac surgery in 28 centers in the United States, Italy, and Argentina. Inclusion criteria were broad and the main exclusions were regular use of fish oil or absence of sinus rhythm at enrollment. Patients were randomized to receive fish oil (1-g capsules containing >840mg n-3-PUFAs as ethyl esters) or placebo, with preoperative loading of 10g over 3 to 5 days (or 8 g over 2 days) followed postoperatively by 2g/d until hospital discharge or postoperative day 10, whichever came first.
The main outcome measure was occurrence of postoperative AF lasting longer than 30 seconds. Secondary end points were postoperative AF lasting longer than 1 hour, resulting in symptoms, or treated with cardioversion; postoperative AF excluding atrial flutter; time to first postoperative AF; number of AF episodes per patient; hospital utilization; and major adverse cardiovascular events, 30-day mortality, bleeding, and other adverse events.
At enrollment, mean age was 64 years; 72.2% of patients were men, and 51.8% had planned valvular surgery. The primary end point occurred in 233 (30.7%) patients assigned to placebo and 227 (30.0%) assigned to n-3-PUFAs (P=0.74). None of the secondary end points were significantly different between the placebo and fish oil groups, including postoperative AF that was sustained, symptomatic, or treated (231 [30.5%] vs 224 [29.6%], P=0.70) or number of postoperative AF episodes per patient (1 episode: 156 [20.6%] vs 157 [20.7%]; 2 episodes: 59 [7.8%] vs 49 [6.5%]; >3 episodes: 18 [2.4%] vs 21 [2.8%]) (P = .73). Supplementation with n-3-PUFAs was generally well tolerated, with no evidence for increased risk of bleeding or serious adverse events.
According to the authors, this large multinational trial among patients undergoing cardiac surgery, perioperative supplementation with n-3-PUFAs, compared with placebo, did not reduce the risk of postoperative AF.