In patients with HFpEF compared to patients without HF, levels of the biomarker myeloperoxidase may be significantly higher.

Myeloperoxidase (MPO) levels are significantly higher in patients with heart failure with preserved ejection fraction (HFpEF) compared with those in individuals without HF, according to a study in the International Journal of Cardiology.

The meta-analysis evaluated metabolomic studies in HFpEF with a focus on MPO, derivatives of reactive oxidative metabolites (DROMs), and carnitine to determine whether they can differentiate HFpEF from HF with reduced ejection fraction (HFrEF) or non-HF.

A systematic search was performed in the Medline and PubMed databases for relevant clinical studies published in English from inception through May 25, 2023. The meta-analysis included 12 articles.

MPO levels were evaluated in 5 studies and were significantly (P <.001) increased in patients with HFpEF compared with non-HF individuals, with a pooled effect size of 0.705 (95% CI, 0.426-0.983) in the random effects meta-analysis. MPO levels were similar in the patients with HFpEF compared with patients with HFrEF, with a pooled effect size of 0.014 (95% CI, -0.123 to 0.152; P =.838).

Using a metabolomic ‘lens’ to evaluate HFpEF, this meta-analysis found that MPO is a significant biomarker of HF compared to non-HF.

Carnitine levels were evaluated in 4 studies, and the random effects meta-analysis showed that they were similar between the non-HF group and the HFpEF group, with a pooled effect size of 0.155 (95% CI, -0.241 to 0.550; P =.443). Carnitine levels were significantly increased (P <.0001) among patients with HFrEF compared with those with HFpEF.