Impact of Dietary Fatty Acids on Cardiac Arrhythmogenesis

Abstract

A recent headline on theHeart.org was “Western Diet Increases MI Risk Worldwide.” In the past 30 years, it has become apparent that dietary fatty acids have a profound impact on the composition of plasma and cardiovascular tissue lipid pools, and as a result, on the risks of cardiovascular disease. Although significant progress has been made to reduce the incidence of death caused by coronary heart disease, it still afflicts ≈450 000 patients per year in the United States, with many of these dying from cardiac arrhythmias.1 Atrial fibrillation (AF), the most common arrhythmia, afflicts more than 2.2 million Americans. It has been estimated that more than 12 million Americans will have AF by 2050 because of the aging of the population as well as the increasing incidence of diabetes and obesity, both risk factors for AF.1 Reasons underlying the increased prevalence of these acquired diseases are complex, involving societal changes in diet, lifestyle, and physical activity. Efforts to address these risk factors seem likely to reduce the burden of cardiac arrhythmia and cardiovascular disease. Although all are important, this review focuses on the relationship between dietary fatty acids and mechanisms of cardiac arrhythmogenesis. ### What Fatty Acids Are Present in the Diet? As shown in Figure 1, fatty acids consist of a straight chain of carbon atoms with a carboxylic end (COOH) and a methyl (CH3) or omega end and are classified based on the saturation of the carbon chain. Common saturated fatty acids, those with no double bonds, include palmitic acid (16:0) and stearic acid (18:0). Foods high in saturated fatty acids include dairy products, red meats, and tropical oils.2 Unsaturated fatty acids are further classified based on the number and location of double bonds. Monounsaturated fatty acids, such as oleic acid (18:1n9), have a single double bond, whereas polyunsaturated fatty acids (PUFA) …