Cardiac Surgery and the Risk of Atrial Fibrillation: an Intervention Trial Evaluating Melatonin

Atrial fibrillation is a common heart rhythm condition that can occur after cardiac surgery and has been associated with an increase in hospital length of stay, overall hospital costs, worsening clinical condition and higher rates of death. Newer research indicates that inflammation is a key contributor to atrial fibrillation in this setting. Melatonin is a naturally made hormone that is regarded as an extremely effective anti-inflammatory substance, with a very favorable safety profile. This clinical trial is being done to test the ability of melatonin to reduce the risk of developing atrial fibrillation after cardiac surgery. This is a research study where patients will be given either oral melatonin at 40 mg or placebo nightly prior to sleep. The study product will start approximately 2 days prior to the scheduled surgery date and will continue until the 3rd day after the operation. The remainder of the clinical care will remain the same. The investigators project that patients who receive melatonin will have a significant decrease in the occurrence of atrial fibrillation after surgery.