Sudden death is a common manifestation of ischemic heart disease and therefore of great public health concern. Unfortunately several promising antiarrhythmic drugs proved not to be effective in preventing sudden deaths. This project would test whether a relatively inexpensive and presumably innocuous therapy, fish oil supplements, can prevent life-threatening arrhythmias. There is ample basic evidence that n-3 fatty acids contained in fish oil supplements may suppress arrhythmias, and a clinical trial seems warranted.