Ethanol abuse and heart disease.

The toxic effects of chronic ethanol abuse on cerebral and hepatic function have long been recognized. The role of ethanol abuse as an etiologic factor in heart disease is less clear and is often attributed to coexistent malnutrition. However, malnutrition has been dissociated from ethanol use in many patients with congestive cardiomyopathy. Studies in various animals provide major support for the role of ethanol as a toxic agent when used in large amounts for a prolonged period. Abnormalities that result from ethanol in test animals include depression of left ventricular performance and metabolic and morphologic changes that parallel the changes in human alcoholics with subclinical mechanical dysfunction of the heart, such as symptomatic cardiac arrhythmias, particularly during intensive alcohol ingestion. What causes the progression to heart failure or arrhythmias is not known, but several factors may be involved. These include, particularly in males, the cumulative effects of ethanol alone or after intensified drinking episodes, excessive exposure to trace metals or superimposed infection. The low prevalence of clinical nutritional deficiency in patients with alcoholic cardiomyopathy and the apparent infrequency of heart failure in patients with cirrhosis or neuropathy supports the view that the cardiac abnormality is often not dependent on malnutrition. Clinical data indicate that the cessation of alcohol intake may reverse the disease or interrupt its progression in many patients. However, the pathogenetic process may continued unabated in some who become abstinent.