In the sixth year of our study of the effect of anesthetics on myocardial metabolism, our efforts will range from the study of halothane and narcotic analgesics in the ischemic pig heart, through the delineations of the myocardial functional and metabolic effects of malignant hyperthermia to the unraveling of fatty acid metabolism in a working perfused heart preparation under the influence of anesthetics. Our goals remain unchanged. We are interested in the relationship between myocardial function and metabolism under the influence of anesthetics for two reasons. We wish to get at the molecular mechanisms for the negative inotropic effect of anesthetics and we would like to establish whether this effect is harmful to the animal being anesthetized.