NON-INVASIVE ASSESSMENT OF MYOCARDIAL ENERGETICS USING 11-C ACETATE POSITRON EMISSION TOMOGRAPHY: SYSTEMATIC REVIEW AND META-ANALYSIS

Background: 11-C acetate PET is a non-invasive imaging modality to assess myocardial oxygen consumption (MVO2), and external efficiency (MEE). We conducted a systematic review and meta-analysis of available literature on this topic. Methods: We searched electronic databases from inception to September 15, 2021, for all studies using 11C-Acetate PET in humans and patients with CVD at rest. Data are presented as mean with 95% CI. Results: 54 studies with 1,182 participants (337 healthy, 845 patients with any CVD) met our inclusion criteria. Mean MVO2 and MEE in studies with healthy controls was 0.11 (0.09, 0.13, I2=99.3%) ml min-1g-1 and 27% (22, 33 I2=98.3%), respectively (Figure). Mean MEE in HFrEF, HFpEF, AS and HCM was 15% (13, 18), 13% (12, 14), 23% (20, 25) and 19% (CI 17, 22), respectively. In HFrEF, both mean MVO2 (difference -0.02,-0.03, -0.01) and MEE (difference -9%, [-13, -6]) were lower vs. healthy controls. In HFpEF, mean MVO2 was higher (difference 0.03, -0.01, 0.07), but mean MEE was similar. In aortic stenosis, mean MVO2 was higher (difference 0.03, [0.01, 0.05]) and mean MEE lower (difference -7%, [-16, 1]) vs. healthy controls. In HCM, mean MVO2 was higher (WMD 0.01, [0.00, 0.02]), and mean MEE was lower (difference -21%, [-33, -8]). Conclusion: Assessment of myocardial energetics using 11-C acetate PET can help understand the pathophysiology of distinct CVD. There is significant heterogeneity in the current literature, and there is an unmet need to standardize protocols and reporting methods