Activation of Neutrophil Extracellular Trap Formation in Patients with Heart Failure and a Preserved Ejection Fraction

Introduction Pathophysiological differences between heart failure (HF) with preserved ejection fraction (HFpEF) and HF with reduced ejection fraction (HFrEF) remain poorly understood. Therefore, we performed pathway analyses from whole-blood transcriptomics to distinguish HFpEF from HFrEF. Methods and Results Lexogen's QuantSeq was used to carry out whole-blood transcriptomics in 500 patients with HF (HFpEF n = 250, HFrEF n = 250). Differential gene expression analysis was performed on all protein-coding genes that met a predefined minimum expression level. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology over-representation analysis was utilized to identify upregulated and downregulated biological pathways. The findings were validated in an independent cohort of 727 patients with HF. Out of 7672 protein-coding transcripts, 217 were upregulated and 110 were downregulated in patients with HFpEF compared with HFrEF. The 3 most significantly upregulated genes were neutrophil-expressed elastase, defensin alpha 4, and pro-platelet basic protein. The 3 most significantly downregulated genes were lymphotoxin beta, bridging integrator 1, and V-set pre-B cell surrogate light chain 3. Translation of differentially expressed genes into biological pathways demonstrated that the most significantly activated KEGG pathway in HFpEF was neutrophil extracellular trap formation. Discussion Transcriptomics analyses suggest activation of neutrophil extracellular trap formation pathways in patients with HFpEF. This pathway is associated with endothelial and coronary microvascular dysfunction and might be a target for future drug development in patients with HFpEF.