Figure 1.

Cardiac metabolism and defects in heart failure. Under normal conditions, cardiomyocytes mostly utilize free fatty acids as their primary substrate. However, with pressure overload and heart failure, cardiomyocytes switch substrate preference to glucose. There is also decreased activity of fatty acid β-oxidation, tricarboxylic acid (TCA) cycle enzymes, and complexes involved in the electron transport chain (ETC) in heart failure. Red arrows show defects in cellular metabolism in heart failure. For more details, please refer to the text.