Myocardial fatty acid metabolism probed with hyperpolarized [1-13C]octanoate

Background The heart normally derives most of its energy from the oxidation of fatty acids. Myocardial metabolism can be monitored non-invasively by MRS using hyperpolarized (HP) 13C-labelled compounds; however, the vast majority of studies reported have used HP pyruvate and did not measure fatty acid catabolism. The myocardial metabolism of HP [1-13C]butyrate and [1-13C]acetate has been reported. The conversion of these short-chain fatty acids to acetyl-CoA does not involve successive rounds of beta-oxidation, as is the case for longer chain fatty acids, which are a more important source of cardiac energy. In this study we examined the applicability of hyperpolarized [1-13C]octanoate, a medium-chain fatty acid, as a probe of myocardial metabolism.