Immunometabolism in heart failure

The interaction between inflammation and metabolism (immunometabolism) is a crucial factor in the pathophysiology of heart failure, whether the cardiac failure originates from ischaemic injury or systemic metabolic disorders, and whether it is associated with reduced or preserved ejection fraction. Ischaemia, metabolic stress and comorbidity-driven systemic inflammation attract innate and adaptive immune cells to the myocardium and induce their polarization towards pro-inflammatory or anti-inflammatory phenotypes through cell-intrinsic metabolic shifts involving oxidative phosphorylation and anaerobic glycolysis. These infiltrating immune cells modulate cardiac and systemic metabolism. The bidirectional metabolic crosstalk between immune cells and parenchymal and stromal cardiac cells contributes to adverse cardiac remodelling. In turn, ischaemic injury and deregulated metabolism stimulate bone marrow and extramedullary myelopoiesis, which increases immune cell recruitment and perpetuates a non-resolving chronic inflammatory state. Pharmacological interventions targeting metabolism have shown promise for improving outcomes in patients with heart failure, but immunomodulatory approaches face multiple challenges. Understanding the complex metabolic pathways and cell-cell interactions that regulate immunometabolism in heart failure is essential to identify new therapies that shift the balance from maladaptive to cardioprotective immune responses. In this Review, we provide a comprehensive overview of the intricate cellular and molecular mechanisms that govern immunometabolism in heart failure and discuss potential approaches to non-invasively monitor and treat patients with heart failure.