Free fatty acids during acute myocardial infarction.

Free fatty acids (FFA) are elevated in plasma soon after the onset of symptoms associated with developing myocardial infarction. Levels above 1200 mu Eq./L. are associated with a significantly increased incidence of serious ventricular arrhythmias, heart block and sudden death. Evidence is presented from experimental myocardial infarction in dogs to show that high levels of FFA can themselves cause arrhythmia, although catecholamines are mainly responsible for the mobilization of FFA during clinical episodes of acute myocardial ischemia. It is postulated that high concentrations of FFA irrespective of the mode of elevation have a deleterious effect on the function of the heart during hypoxia. These observations offer a new therapeutic approach to the management of arrhythmias and of acute myocardial infarction. Attention should be directed to blocking FFA release from adipose tissue and to providing the hypoxic myocardial cells with a concentration of glucose which will provide adequate substrate for all energy requirements of the heart.