Could 13C MRI assist clinical decision-making for patients with heart disease?

Even at this early stage of development, it is clear that the imaging of hyperpolarized (13)C-enriched molecules and their metabolic products offers a new approach to the study of the physiology and disease of the heart. The technology is practical in humans and, for this reason, we consider whether a role in clinical decision-making should motivate further development. The range of interventions available to treat coronary and valvular heart disease is already extensive, and new options are imminent. Yet the appropriate management of patients with left ventricular dysfunction can be challenging because the mechanism of reduced function may be unclear and the ability of the ventricle to respond to therapy may be difficult to predict. Pyruvate is a promising early target for development as a diagnostic agent because it lies at a critical branch point in cardiac biochemistry. The rate of metabolism of hyperpolarized pyruvate to CO(2) relative to lactate may prove to be a useful indicator of preserved mitochondrial function, and therefore provide a specific signal of viable myocardium. Other species including physiological substrates and nonphysiological molecules may provide additional information. Once suitable technology becomes available, it is likely that clinical research will progress quickly. The ability to monitor directly specific metabolic pathways may lead to an improvement in the selection of patients who will benefit from interventions, pharmacologic or otherwise.