Abstract 6929: Acute Echocardiographic Effects of Exogenous Ketone Administration and Relationship to Myocardial Glucose Uptake on Fdg-pet

Background: Interest in therapeutic applications of exogenous ketones has grown significantly, spanning endurance athletes to heart failure (HF) patients. Exogenous ketones engender significant effects on cardiac function in HF and provide an ergogenic benefit in athletes. We sought to assess the effects of exogenous ketones on cardiac function and metabolism in healthy participants. Methods: Twenty healthy participants completed echocardiograms before and 30 minutes after administration of ketone ester (KE), followed by FDG-PET imaging. We used mixed effects linear regression to assess the association between regional left ventricular (LV) strain on the post-KE drink echocardiogram with regional myocardial glucose uptake (SUV myocardium/blood pool) on FDG-PET (N=176 myocardial segments). Results: Mean age was 307 years, 50% were female, 45% were non-white, and average BMI was 24.33.1 kg/m 2 . Ketone ingestion acutely elevated beta-hydroxybutyrate levels (median, 25 th -75 th percentile) from 0.12 (0.10-0.32) to 3.23 (2.40-4.97) mmol/L (p<0.001). After KE consumption, LV/RV/LA function strain all augmented, while systemic vascular resistance decreased ( Figure ). Specifically, LV ejection fraction (3.5±2.1%, p<0.001), global longitudinal strain (2.0±1.5, p<0.001), cardiac output (1.1±0.8 L/min, p<0 . 001), right ventricular S’ velocity (1.1±1.4, p=0.004), LA reservoir strain (7±11%, p=0.005) and LA contractile strain (4±5%, p=0.001) increased. After multivariable regression, each halving of regional glucose uptake was independently associated with a 2.2% increase in regional strain (p=0.016). Conclusions: KE ingestion acutely augments even in healthy participants, mirroring many hemodynamic effects seen in HF. The ability of KE to augment myocardial function was directly associated with reducing myocardial glucose uptake, supporting myocardial metabolic modulation as a mechanism of benefit.