Abstract
BACKGROUND: The interplay between mitochondrial dysfunction and immune infiltration in heart failure with preserved ejection fraction (HFpEF) remains poorly understood. This study aimed to elucidate this relationship and identify key regulatory genes. METHODS: We integrated bioinformatics analyses of human HFpEF datasets (GSE108904, GSE126062) with experimental validation. Differential expression analysis, weighted gene co‐expression network analysis (WGCNA), and the MitoCarta3.0 database were used to identify hub mitochondrial genes. Immune cell infiltration was assessed, and key findings were validated in peripheral blood mononuclear cells (PBMCs) from HFpEF patients and in mouse/cell models of the disease. RESULTS: Two hub mitochondrial genes, CHCHD1 and EFHD1, were associated with HFpEF. Immune profiling revealed increased macrophage infiltration in HFpEF, which was negatively correlated with the expression of both hub genes. Experimental validation confirmed a significant decrease in EFHD1 expression in HFpEF patient PBMCs, HFpEF mouse heart tissues, and a cellular inflammation model. Critically, EFHD1 expression showed a significant negative correlation with clinical indicators of heart failure (NT‐proBNP and E/e' ratio). CONCLUSION: Our integrated analysis reveals CHCHD1 and EFHD1 as key mitochondrial genes linking mitochondrial dysfunction to immune dysregulation in HFpEF, offering new insights into its molecular mechanisms and potential therapeutic targets.