Figure 4.

Hyperpolarized ¹³C magnetic resonance imaging (MRI) results describing alterations to pyruvate dehydrogenase complex (PDC) flux and [¹³C]lactate production with the pathogenesis of dilated cardiomyopathy (DCM), following infusion of hyperpolarized [1-¹³C]pyruvate. (A) Representative pyruvate (Pyr, top), bicarbonate (Bic, middle), and lactate (Lac, bottom) ¹³C MR images taken from the same pig and at weekly intervals during the pacing protocol, until DCM developed. The images displayed for each metabolite were selected from the same, mid-papillary slice and in the same respiratory cycle. Signal intensity in the pyruvate image was scaled based on 15–100% of the maximum pyruvate signal at week 0, whereas the bicarbonate and lactate signal intensities were scaled based on 15–100% of the maximum bicarbonate signal intensity at week 0. (B) Relative changes to PDC flux with DCM in five pigs.