Does acute free fatty acid depletion affect cardiac work and efficiency differently in failing hearts compared to healthy hearts?
Failing hearts are unexpectedly more dependent on free fatty acid availability than healthy hearts, suggesting both glucose and fatty acid oxidation are required for optimal function.
Acutely decreased serum FFA depresses cardiac work. In healthy hearts, this is accompanied by parallel decrease in oxidative metabolism, and myocardial efficiency is preserved. In failing hearts, FFA depletion did not downregulate oxidative metabolism, and myocardial efficiency deteriorated. Thus, failing hearts are unexpectedly more dependent than healthy hearts on FFA availability. We propose that both glucose and fatty acid oxidation are required for optimal function of the failing heart.
Tuunanen et al. (Mon,) studied this question.