[The role of omega-3 fatty acids from fish in prevention of cardiovascular diseases].

Fish and fish oil are rich sources of omega-3 fatty acids--essential polyunsaturated fatty acids. These acids in doses of 1 g per day have been shown to significantly reduce the all-cause mortality in post myocardial infarction (MI) patients and the risk for sudden death caused by cardiac arrhythmias. One of the recently most studied mechanisms that may contribute to this benefits of omega-3 fatty acids is their anti-arrhythmic effect. Namely, these acids influence membrane ion channels, increase ventricular fibrillation threshold and increase heart rate variability. Although the data concerning primary prevention is less straightforward than the data relating secondary prevention, it seems that the use of omega-3 fatty acids in primary prevention might be justified as well. In higher doses (2 to 4 g per day) they are used to treat hypertriglyceridemia. Potential mechanisms by which omega-3 fatty acids may reduce risk for cardiovascular disease include also antithrombotic (they decrease platelet aggregation/reactivity, reduce plasma viscosity, enhance fibrinolysis) and anti-inflammatory effects (e.g. they decrease IL-6, MCP-1, TNF), improving vascular endothelial cell function (e.g. they increase availability of nitric oxide), reducing expression of endothelial cells adhesion molecules, inhibiting smooth muscle cells migration and proliferation, and reducing blood pressure. Based upon clinical studies the use of omega-3 fatty acids should be considered today at least as a part of comprehensive secondary prevention strategy in post-MI patients. It has been also shown that adding highly concentrated omega-3 fatty acids to standard treatment in the secondary prevention of MI is cost effective versus standard treatment alone. Particularly important is that there are no significant drug interactions with omega-3 fatty acids.