Heart failure & cardiomyopathiesResearch article

Protein biomarkers associated with left bundle branch block in patients with heart failure and reduced ejection fraction

ESC Heart FailPublished

  • propensity score matching
  • omics approach
  • proximity extension assay

Authors' conclusion

In HFrEF, LBBB was associated with an altered circulating proteome. FGF2 and EGFR were highly dysregulated between the groups and the MAPK signalling pathway was affected, all of which may be pathophysiologically involved in the accelerated cardiac remodelling observed in these patients. These findings constitute a foundation for future studies of relevant LBBB-related biomarkers, treatment targets, and mechanisms behind the cardiac remodelling observed when LBBB is superimposed on HFrEF.

Study context

Population
Patients with Heart Failure with Reduced Ejection Fraction (HFrEF) from the BIOlogy Study to TAilored Treatment in Chronic Heart Failure databasedatabase, 268 cases and 268 matched controls · HFrEF + left bundle branch block (LBBB) 268 · HFrEF - LBBB 268
Participants
4,254 patients
Comparison
relative plasma concentrations of 364 proteins between the two groups
  • HFrEF + LBBBn = 268
  • HFrEF - LBBBn = 268

Main finding

As reported in the abstract

Plasma proteins up- or downregulated

proteins up- or downregulated in HFrEF + LBBB compared with HFrEF - LBBB, out of 364 assessed

41

share of proteins assessed

11%

Further findings

Gene ontology pathway enrichment among upregulated proteins

mainly involved in immune response and cell signalling and included the mitogen-activated protein kinase (MAPK) pathway

Original publication

Protein biomarkers associated with left bundle branch block in patients with heart failure and reduced ejection fraction. ESC Heart Fail. Published 13 January 2026. doi:10.1093/eschf/xvag009

Summarised from the published abstract; every number is checked against it