Myocardial and skeletal muscle function in habitual alcoholics and its relation to serum myoglobin

Lower-than-normal serum myoglobin levels are regularly found in habitual alcoholics without recent alcohol intake and were also confirmed in this study. It was hypothesized that these low levels reflect reduction in myocardial and skeletal muscle function. To study this hypothesis, heart and skeletal muscle function was evaluated and related to serum myoglobin levels. Myocardial function evaluated by noninvasive techniques was significantly decreased and heart muscle mass increased (p less than 0.001) in circulatory asymptomatic alcoholics compared with age- and weight-matched healthy male control subjects. The working capacity of the alcoholics was lower than expected during dynamic exercise testing (p less than 0.001), and maximal muscle power was reduced during isokinetic muscle testing (p less than 0.05). Myoglobin levels were correlated to the degree of myocardial diastolic dysfunction (p less than 0.01) but not to working capacity during dynamic or isokinetic exercise testing. The observation that myocardial affection was related to low serum myoglobin suggests that the mechanisms behind reduced myoglobin release are linked to the chronic muscle affection in alcoholics.