Alcohol and malnutrition in the pathogenesis of experimental alcoholic cardiomyopathy

In this study, the morphology and the catecholamine levels of the myocardium in both well-nourished and malnourished alcohol-fed rats were examined. Alcohol has been administered to rats for 16 weeks. Rats fed a diet containing alcohol corresponding to 40 per cent. of total calorific intake and inadequate amounts of calories and nutrients developed morphological changes in the heart, while the controls did not. In addition, an increase in cardiac noradrenaline concentration and heart: body weight ratio could be observed. There were no differences in myocardial morphology and catecholamine concentration between well-nourished rats fed alcohol as 35 per cent. of the calorific intake and pair-fed controls. A dispute exists about whether alcohol is directly toxic to the heart or indirectly injurious due to associated dietary deficiency. The present results, taken together, make the theory of cardiotoxicity of alcohol an unlikely one, at least in the case of the rat; and they offer considerable support for the hypothesis that the association between chronic consumption of alcoholic beverages and cardiomyopathy is a result of a primary multifactorial nutritional deficiency, resulting from displacement of nutrient-associated calories by the "empty" calories--devoid of protein, vitamins, and minerals--of alcohol, and/or a secondary nutritional deficiency due to injurious effects of alcohol on the liver, pancreas and intestine. It is suggested that continued exposure to high levels of catecholamine, directly related to malnutrition, may play a role in the development of myocardial pathology.