SUVmean ratios of liver/muscle and lung/muscle from 13N-NH3 PET perfusion outperformed traditional myocardial viability parameters in predicting survival after CABG

Purpose Myocardial viability evaluation in predicting survival after coronary artery bypass graft (CABG) remains debatable. Thus, this study aimed to investigate the role of 13 N-NH 3 / 18 F-FDG PET myocardial viability scan in predicting treatment outcomes and survival. Methods 90 patients with CABG and pre-surgical PET-based myocardial viability scan were retrospectively reviewed. Perfusion-metabolism features, myocardium motion parameters, and patient characteristics were recorded. Additionally, the SUVmean of blood pool, lung, liver, spleen, and muscle were measured and the SUVmean ratios were calculated. Factors associated with treatment outcomes and survival were analyzed by Logistic and Cox regressions. Nomogram models were subsequently established to predict ejection fraction (EF) improvement and survival outcomes. Results The mean EF of these 90 patients was 38.1 ± 9.5% and 46.0 ± 9.2% before and after CABG surgery, and 35 patients (38.9%) achieved EF improvement ≥ 10%. EF measurements by PET and echocardiogram showed a reasonable linear correlation ( R = 0.752). Sex, pre-surgical EF, mismatch of the left ventricle, total perfusion deficit (TPD), and peak ejection rate (PER) were independent predictive factors of EF improvements. Surgery waiting time, valve damage, and SUVmean ratio of Liver/Muscle were independently predictive of event-free survival (EFS), while valve damage, together with SUVmean ratio of either Liver/Muscle or Lung/Muscle, were independently predictive of overall survival (OS). Conclusion Although traditional cardiac parameters from PET-based myocardial viability can effectively predict EF improvements after CABG, SUVmean ratios of liver/muscle and lung/muscle from 13 N-NH 3 PET perfusion outperformed these parameters in predicting survival.