Omega-3 Fatty Acids for Prevention of Post-Operative Atrial Fibrillation (OPERA)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00970489
Recruitment Status : Completed
First Posted : September 2, 2009
Results First Posted : April 10, 2017
Last Update Posted : April 10, 2017
The OPERA Investigators
Information provided by (Responsible Party):
Dariush Mozaffarian, MD, Brigham and Women's Hospital

August 31, 2009
September 2, 2009
July 26, 2013
April 10, 2017
April 10, 2017
August 2010
May 2012   (Final data collection date for primary outcome measure)
Any First Post-op Atrial Fibrillation or Flutter (AF) [ Time Frame: up to 10 days post-surgery or discharge, whichever sooner ]
Primary: Occurrence of post-CS AF (atrial fibrillation or flutter) of at least 30 seconds duration and confirmed by rhythm strip or 12-lead ECG. This will include definite AF and probable AF (SVT likely to be AF depending on rate and other characteristics).
Atrial Fibrillation [ Time Frame: up to 10 days post-surgery or discharge, whichever sooner ]
Complete list of historical versions of study NCT00970489 on Archive Site
  • Post-op Af [ Time Frame: up to 10 days post-surgery or discharge, whichever sooner ]
    Secondary AF endpoints included post-op AF that was sustained (>1 hour), symptomatic, or treated with pharmacological or electrical cardioversion; post-op AF excluding atrial flutter; time to first post-op AF; and the number of post-op AF episodes per patient. OPERA also evaluated the total number of in-hospital days in which any post-op AF, including sustained post-op AF, was present; and the proportion of in-hospital days free of any post-op AF. All potential episodes of post-op AF and other tachyarrhythmias were reviewed and adjudicated by a centralized Events Committee of cardiac electrophysiologists. Additional endpoints included resource utilization, major adverse cardiovascular events (MACE), arterial thromboembolism, and 30-day mortality.
  • Other Arrhythmias [ Time Frame: up to 10 days post-surgery or discharge, whichever sooner ]
    • The first 3 suspected episodes of atrial fibrillation or flutter of at least 30 sec duration following randomization were documented, including the following information:

      • Printed or digital rhythm strip and/or 12-lead ECG.
      • Recording of time of onset and time of cessation.
      • Additional documentation of temporally associated signs of symptoms, such as new or worsening chest pain, shortness of breath, or lightheadedness; drop in blood pressure requiring escalation of fluid or pressor treatment; or need for electrical or pharmacologic cardioversion.
    • The first suspected episode of each of other supraventricular or unknown narrow-complex tachycardia of at least 30 sec duration following randomization was also documented.
  • Other Endpoints [ Time Frame: up to 10 days post-surgery or discharge, whichever sooner ]
    1. Number of days in the ICU, of telemetry monitoring, and of total hospital stay.
    2. Non-AF arrhythmias of at least 30 sec duration, including non-AF-SVT, ventricular tachycardia (VT), and ventricular flutter (VF), assessed and adjudicated by the Events Committee.
    3. MACE: Combined total mortality, myocardial infarction, and stroke.
    4. Bleeding, assessed by (a) chest tube output in the 24 hour period following surgery and (b) total number of packed red blood cell (RBC) transfusions from enrollment to end of treatment (hospital discharge or post-op day 10).
    5. Significant adverse events: Discontinuation of study treatment, at the discretion of the treating physicians, for suspected significant allergic reaction, severe gastrointestinal intolerance, significant bleeding, or other side effects requiring discontinuation.
    6. Thirty-day mortality assessed
    7. One-year mortality assessed
Occurrence of sustained or symptomatic atrial fibrillation [ Time Frame: up to 10 days post-surgery or discharge, whichever sooner ]
Not Provided
Not Provided
Omega-3 Fatty Acids for Prevention of Post-Operative Atrial Fibrillation
(OPERA)Randomized Clinical Trial to Examine Whether Peri-operative Intake of n-3 Polyunsaturated Fatty Acids Will Reduce the Occurrence of Post-operative Atrial Fibrillation in Patients Undergoing Cardiac Surgery
This is a large multi-center study to examine whether peri-operative intake of n-3 polyunsaturated fatty acids (PUFA) will reduce the occurrence of post-operative atrial fibrillation or flutter (AF) in patients undergoing cardiac surgery (CS).
Not Provided
Phase 3
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Atrial Fibrillation
  • Drug: Omega -3 fatty acids
    10g dose of oral omega-3 fatty acid capsules over 3-5 days before surgery (or 8 g over 2 days before surgery), including the morning of surgery, followed by 2g/d after surgery for 10 days, or until discharge, whichever occurs first.
  • Drug: Placebo
    Olive Oil capsules
  • Experimental: Omega-3 fatty acid capsules
    Intervention: Drug: Omega -3 fatty acids
  • Placebo Comparator: Olive Oil capsule
    Intervention: Drug: Placebo

*   Includes publications given by the data provider as well as publications identified by Identifier (NCT Number) in Medline.
Same as current
June 2012
May 2012   (Final data collection date for primary outcome measure)

Inclusion Criteria:

  • Age 18 years or over
  • Scheduled for CS on the following day or later, including coronary artery bypass, valve surgery, any other open cardiac surgery (i.e., that includes opening of the pericardium), or any combination.
  • Sinus rhythm on current ECG (sinus bradycardia, sinus tachycardia, and ectopy are acceptable).

Exclusion Criteria:

  • Regular use (3 or more days/week) of fish oil within the past 4 weeks.
  • Known allergy or intolerance to fish oil or corn oil.
  • Currently pregnant.
  • Unable to provide informed written consent.
  • Current or planned cardiac transplant or LVAD
Sexes Eligible for Study: All
18 Years and older   (Adult, Older Adult)
Contact information is only displayed when the study is recruiting subjects
United States
Not Provided
Not Provided
Dariush Mozaffarian, MD, Brigham and Women's Hospital
Brigham and Women's Hospital
The OPERA Investigators
Principal Investigator: Dariush Mozaffarian, MD DrPH Harvard School of Public Health
Principal Investigator: Roberto Marchioli, MD Laboratory of Clinical Epidemiology of Cardiovascular Disease Department of Clinical Pharmacology and Epidemiology Consorzio Mario Negri Sud Via Nazionale 8/A S. Maria Imbaro (Chieti), 66030 ITALY
Brigham and Women's Hospital
February 2017

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP