The role of macrophages in cardiac diseases: a review of the origins, functional diversity, and therapeutic potential

Macrophages are important immune cells for cardiac development, homeostasis, and the response to pathological injury and inflammation. Single-cell sequencing and fate-mapping technologies have revealed the heterogeneity and development of cardiac macrophages. They are classed into two main groups: embryonic tissue-resident and bone marrow-derived macrophages. These different macrophage subsets show complex functions in cardiac diseases such as inflammation regulation, tissue repair, metabolic reprogramming and intercellular communication within the cardiac microenvironment. This review discusses the developmental sources, phenotypic diversity, metabolic features and mechanistic functions of cardiac macrophages in different cardiac disorders. We focus on macrophage polarization, metabolic regulation during disease progression and targeted strategies and future research directions.