Prevention of Cardiac Arrhythmias by n-3 Fatty Acids

Abstract

The recently published DART study showed that ingesting fatty fish two or three times weekly by male subjects following a myocardial infarction was associated with a reduction in total mortality from heart attacks but not in the incidence of infarction.¹ These results suggest that the beneficial effect of n-3 fatty acids maybe mediated by preventing arrhythmias ensuing during acute myocardial ischemia — the major cause of death from heart attacks. Indeed, it had been shown already in experimental myocardial infarction in rats that different dietary interventions may have dramatic effects on arrhythmias occurring during ischemia and/or reperfusion. A diet high in saturated fat was associated with an increased incidence and duration of ventricular fibrillation during ischemia as well as during post-ischemic reperfusion of the coronary arteries. A diet rich in sunflower seed oil had a moderate protective effect, whereas a diet enriched with tuna fish oil, with a high content of the long chain polyunsaturated n-3 fatty acids (n-3 PUFAs) EPA and DHA, was associated with a very significant reduction in ventricular fibrillation, especially in older animals.²