Abstract Body: Introduction: Heart failure with preserved ejection fraction (HFpEF) is a heterogenous clinical syndrome that accounts for nearly half of all heart failure cases world-wide. The pathophysiological mechanisms underlying HFpEF include a variety of extracardiac abnormalities such as metabolic derangements, arterial hypertension, and microvascular endothelial dysfunction, that all drive left ventricular remodeling and dysfunction. The phenotypic diversity presented in HFpEF involves functional and structural changes in several organs including the liver. As a highly vascularized organ, the liver is highly sensitive to any hemodynamic changes in the heart and clinical studies have established the presence of liver injury in HFpEF patients. However, there is limited evidence of this relationship in preclinical mouse models, thereby hindering the exploration of the pathological mechanisms linking the two organs. Cardio-hepatic interactions are poorly understood yet play a critical role in the pathophysiology of HFpEF where aberrant metabolic signaling pathways such as insulin resistance, inflammation and oxidative stress significantly contribute to disease progression and further perpetuate a vicious cycle of cardio-hepatic deterioration. Hypothesis: With limited preclinical data in the field, we sought to elucidate the potential pathophysiological mechanisms driving cardio-hepatic crosstalk in HFpEF. Methods: We used a two-hit preclinical mouse model that recapitulates cardiometabolic HFpEF to characterize the coexistence of cardiac and hepatic dysfunction in HFpEF. Male mice were kept on the HFpEF model for 15 weeks and subjected to echocardiography, glucose tolerance tests, histopathology, and multi-omics analyses. Results: We report that markers of HFpEF severity such as diastolic dysfunction and left ventricular hypertrophy, significantly correlated with hepatic injury and dysfunction that exacerbated metabolic dysfunction-associated fatty liver disease (MAFLD) progression. Impaired energy substrate utilization due to fatty acid dysregulation was a major mechanism underlying cardio-hepatic crosstalk in HFpEF. Conclusion: Our findings highlight fatty acid metabolism as a potential target to mitigate inter-organ dysfunction in HFpEF, representing a promising opportunity to create new treatment paradigms and drive positive outcomes in HFpEF.