Leukocyte activation and inflammation in acute myocardial infarction: novel insights from cell population data

Immune dysregulation is strongly involved in acute myocardial infarction (AMI), driving sustained inflammation and myocardial damage. A better understanding of the immune cell response to AMI is needed, beyond neutrophil and monocyte counts. Cell Population Data (CPD) analysis, including granularity (SSC), size (FSC), activation (SFL), and heterogeneity indices, offers deeper insights into the dynamics of leukocyte populations.

Our goal was to investigate CPD as prognostic biomarkers for cardiovascular (CV) mortality after AMI and to assess their links to inflammatory and lipid markers.

Samples from 572 patients with AMI were collected at the admission in the cardiology intensive care unit. In addition to routine blood tests, CPD was acquired on an automated haematology analyser. Plasma inflammatory markers, as well as detailed fatty acid profiles, were also measured. A one-year follow-up was then conducted to assess CV mortality.

Neutrophil, monocyte, and immature granulocyte (IG) counts and neutrophil heterogeneity of fluorescence (NE-WY) were associated with CV deaths, myocardial infarction (MI), and inflammatory biomarkers such as hs-CRP and IL-6. On the opposite, lymphocyte count was inversely associated with CV death and inflammatory markers. Monocyte count and CPD were correlated with saturated fatty acids, especially palmitic acid.

Our findings demonstrate that CPD, particularly parameters related to neutrophils and monocytes, are robustly linked to inflammation and the occurrence of CV mortality. Importantly, these CPD-readily accessible through standard clinical haematology analysers-hold significant potential as predictive biomarkers for clinicians to assess cardiovascular risk in routine practice.