Myocardial Pyruvate Metabolism Before and After CABG in Three-Vessel Disease Using Hyperpolarized Carbon-13 MRI

Hyperpolarized [1-¹³C]pyruvate MRI provides real-time, radiation-free insight into myocardial pyruvate metabolism and mitochondrial oxidative capacity, yet its utility in patients with severe multivessel coronary artery disease before and after surgical revascularization remains unknown. Here we show, in the first prospective study applying this technique to three-vessel disease, that serial imaging is feasible and safe with no serious adverse events in 22 injections. Healthy myocardium displayed a bicarbonate-to-total hyperpolarized carbon product ratio of 0.66 ± 0.13, indicating that the majority of pyruvate undergoes oxidation. Patients exhibited significantly lower ratios in the inferolateral segment (P = 0.03) with reciprocal increases in lactate, and global ratios correlated with left ventricular ejection fraction (r = 0.695, P = 0.006). Post-revascularization changes were heterogeneous across individuals. These findings establish hyperpolarized 13C MRI as a powerful tool for noninvasive assessment of myocardial metabolism in multivessel coronary artery disease and support its potential for longitudinal therapeutic monitoring.