The kinetics of circulating monocyte subsets and monocyte-platelet aggregates in the acute phase of st-elevation myocardial infarction associations with 2-year cardiovascular events

In experimental myocardial infarction (MI), a rise in cell counts of circulating monocyte subsets contributes to impaired myocardial healing and to atherosclerotic plaque destabilization. In humans, the prognostic role of monocyte subsets in patients suffering STelevation MI (STEMI) is still unclear. In the present study, we aimed to determine the kinetics of the 3 monocyte subsets (classical CD14CD16-, intermediate CD14CD16, and nonclassical CD14CD16 monocytes), as well as the subset-specific monocyte-platelet aggregates (MPA), in acute STEMI followed by primary percutaneous coronary intervention (PCI), and their relationships with cardiovascular outcomes during a 2-year follow-up. Monocyte subsets and MPA were measured in 100 STEMI patients receiving primary PCI on days 1, 2, 3, 5, and 7 of symptom onset, which were compared with 60 stable coronary heart disease patients and 35 healthy volunteers. From day 1 to day 7, significant increases in the counts of CD14CD16 monocytes and CD14CD16 MPA were observed, with peak levels on day 2. During a median followup of 2.0 years, 28 first cardiovascular events (defined as cardiovascular death, nonfatal ischemic stroke, recurrent MI, need for emergency or repeat revascularization, and rehospitalization for heart failure) were recorded. After adjustment for confounders, CD14CD16 monocytosis (day 1 [HR: 3.428; 95% CI: 1.597-7.358; P=0.002], day 2 [HR: 4.835; 95% CI: 1.106-21.13; P=0.04], day 3 [HR: 2.734; 95% CI: 1.138-6.564; P=0.02], and day 7 [HR: 2.647; 95% CI: 1.196-5.861; P=0.02]), as well as increased levels of CD14CD16 MPA measured on all time points (days 1, 2, 3, 5, and 7), had predictive values for adverse cardiovascular events. In conclusion, our data show the expansion of the CD14CD16 monocyte subset during acute phase of STEMI has predictive values for 2-year adverse cardiovascular outcomes in patients treated with primary PCI. Future studies will be warranted to elucidate whether CD14CD16 monocytes may become a target cell population for new therapeutic strategies after STEMI.