Objective Adverse left ventricular (LV) remodelling is the major determinant of heart failure and mortality in survivors of ST-elevation myocardial infarction (STEMI). The role of fibroblast growth factor 23 (FGF-23) for LV remodelling prediction after STEMI is unknown. We therefore aimed to investigate the relation between circulating FGF-23 and LV remodelling following revascularised STEMI.

Methods In this prospective observational study, we included 88 consecutive patients with STEMI treated by primary percutaneous coronary intervention. FGF-23 concentrations were measured 2 (IQR: 2–2) days after symptom onset. Cardiac magnetic resonance was performed 2 (IQR: 1–3) days as well as 4 (IQR: 4–5) months after infarction to evaluate LV remodelling, defined as ≥20% increase in LV end-diastolic volume.

Results Levels of FGF-23 were significantly higher in patients who developed LV remodelling (n=11, 13%) as compared with those without LV remodelling (152.6 (102.5–241.3) vs 75.8 (58.6–105.4) relative units per millilitre, p=0.002). The association between FGF-23 and LV remodelling remained significant (OR: 14.1, 95% CI 2.8 to 70.9; p=0.001) after adjustment for biomarkers reflecting myocardial necrosis (high-sensitivity cardiac troponin T (hs-cTnT)), myocardial stress (N-terminal pro B-type natriuretic peptide (NT-proBNP)) and inflammatory state (high-sensitivity C reactive protein (hs-CRP)). Moreover, a multimarker approach adding FGF-23 to the established LV remodelling-predictive biomarkers (hs-cTnT, NT-proBNP and hs-CRP) led to a net reclassification improvement of 0.92 (95% CI 0.44 to 1.41, p<0.001) and to an integrated discrimination improvement of 0.16 (95% CI 0.08 to 0.24, p<0.001).

Conclusions Circulating FGF-23 is independently associated with LV remodelling after reperfused STEMI. A comprehensive multimarker strategy that includes FGF-23 provides incremental prognostic value for prediction of LV remodelling.