Simultaneous assessment of cardiac metabolism and perfusion using copolarized [1-13 C]pyruvate and 13 C-urea.

PURPOSE: To demonstrate the feasibility of imaging a bolus of co-polarized [1-13 C]pyruvate and 13 C-urea to simultaneously assess both metabolism and perfusion in the rodent heart. METHODS: Copolarized [1-13 C]pyruvate and 13 C-urea was imaged using a multi-echo, flow-sensitized spiral pulse sequence. Healthy rats were scanned in a two-factor factorial design (n = 12 total; metabolism: overnight fasting versus fed with dichloroacetate injection; perfusion: rest versus adenosine stress-induced hyperemia). RESULTS: Alterations in metabolism were detected by changes in pyruvate metabolism into 13 C-bicarbonate. Statistically independent alterations in perfusion were detected by changes in myocardial pyruvate and urea signals. CONCLUSION: The new pulse sequence was used to obtain maps of metabolism and perfusion in the rodent heart in a single acquisition. This hyperpolarized 13 C imaging test is expected to enable new studies in which the cardiac metabolism/perfusion mismatch can be studied in the acute environment. Magn Reson Med 77:151-158, 2017. © 2016 The Authors Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance in Medicine.