Influence of acute ethanol ingestion on myocardial fatty acid metabolism

Long chain fatty acids are major energy sources of the myocardium. Previous investigations had shown that iodinated long chain fatty acids show similar kinetics in myocardial lipid metabolism as their 11-C-labelled natural analogues. 123-I-omega-heptadecanoic acid (123-I-IHA) was used as stearic acid analogue to measure the effect of ethanol ingestion on myocardial fatty acid metabolism in man, using the conventional gamma-camera. Nine individuals without sign of disease wereselected on the basis of a regular ethanol consumption of approximately 40 g per day. Following 8 hours of fasting the resting patients received 3 mCi 123-I-IHA intravenously. Images were obtained at intervals of 2 minutes over a period of 40 minutes. The pattern of accumulation and the half time of elimination were measured in the LAO-450 position for various left ventricular myocardial areas. Free iodine space was labelled and subtracted from the gross images. - The second investigation was made at rest 14 days later following a 8 hour period of fasting and at the end of a 2 hours long consumption of 100 g ethanol so that an average ethanol level in the peripheral blood of 0,9% was reached. At the same time blood sugar, cholesterol and triglycerides were analyzed. There was a temporary influence of ethanol on the pattern of accumulation and on the regional distribution of elimination half times. The individual responses appeared unpredictable. Changes of regional accumulation could not be correlated with regional changes of elimination half times. The data indicate the usefulness of 123-I-IHA for detecting metabolic changes in the myocardium induced by ethanol. The effect was similar to the results in early forms of cardiomyopathy. (Author)