The number of circulating CD14+ cells is related to infarct size and postinfarct volumes in ST segment elevation myocardial infarction but not non-ST segment elevation myocardial infarction

Left ventricular (LV) remodelling after acute myocardial infarction (MI) is characterized by increased LV volumes, which result in impairment of myocardial function (1,2). Many factors influence LV remodelling, particularly infarct location and the extent of necrosis (3). Acute MI is associated with an increased release of monocytes into the bloodstream; these monocytes reportedly contribute to ischemic tissue healing after acute MI, which should help to prevent LV remodelling (4–6). Recently, new research has provided more insight into the sequential mobilization and respective roles of the different monocyte subsets in acute MI (7–9). Particularly, Tsujioka et al (8) demonstrated that the CD14+CD16− subset is associated with the extent of myocardial salvage in ST segment elevation MI (STEMI) patients with large infarctions. However, the role of CD14+ monocytes has not been studied in the context of non-ST segment elevation MI (NSTEMI), as emphasized by Kavsak and Jaffe (10). Thus, given the hematopoietic origin of CD14+ monocytes, which increase in peripheral blood in acute MI, we aimed to assess the relationship among the number of circulating CD14+ cells, infarct size and LV remodelling in both STEMI and NSTEMI patients, as assessed by magnetic resonance imaging (MRI) five days after MI and six months after MI.