Muscle energy metabolism in severe chronic congestive heart failure--effect of treatment with enalapril.

By using biopsies, skeletal muscle metabolism was investigated in 22 patients with severe chronic heart failure. All the patients were in New York Heart Association functional class IV and constituted a subgroup of the previously published CONSENSUS trial. After this initial investigation of muscle metabolism in patients with chronic heart failure, the influence of the angiotensin converting enzyme inhibitor, enalapril, on skeletal muscle metabolism was studied by randomizing the patients in a double-blind manner to receive either placebo (n = 11) or enalapril (n = 11) in addition to conventional treatment. At the time of inclusion, the muscle content of energy-rich compounds, i.e. glycogen and the high energy phosphates, adenosine triphosphate (ATP) and phosphocreatine, was reduced as compared with healthy subjects and muscle lactate content tended to be higher than normal. Following study treatment, no significant changes occurred, neither within nor between the two subgroups. Thus, patients with severe chronic congestive heart failure display metabolic derangement in muscle, which, in this study, was not corrected by treatment with enalapril.