Association between n-3 fatty acid status in blood and electrocardiographic in predictors of arrhythmia risk healthy volunteers

There are strong indications that intake of very long chain n-3 polyunsaturated fatty acids (n-3 PUFA) from fish reduces the risk of heart disease, possibly by preventing cardiac arrhythmia.(1-3) However, the mechanism behind such an antiarrhythmic effect is not clear. Therefore, we investigated whether n-3 fatty acids may protect against heart disease via increased heart rate variability, a risk predictor for mortality and arrhythmia.(4-6) Another risk predictor for all-cause and cardiac mortality is a longer duration of QT interval(7,8) corrected for heart rate (QTc interval). In dogs, infusion with n-3 free fatty acids not only prevented cardiac arrhythmia, but also decreased the duration of the QTc interval.(9) We investigated, in a cross-sectional study of 53 healthy volunteers, the association of intake of n-3 PUFA with heart rate variability and with length of the QTc interval. To assess habitual intake of n-3 fatty acids, we used the fatty acid composition in cholesteryl esters.(10).