ABC | Volume 110, Nº4, April 2018

Original Article Association of Monocyte Count on Admission with the Angiographic Thrombus Burden in Patients with ST‑Segment Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention Zuoyan Wang, Na Liu, Lihui Ren, Licheng Lei, Huiming Ye, Jianjun Peng Beijing Shijitan Hospital - Capital Medical University, Beijing Shi - China Mailing Address: Jianjun Peng • Departamento de Cardiologia, Hospital Pequim Shijitan, Universidade Médica Capital. N°.10 Road Tieyi, Distrito de Haidian, Pequim, 100038, China. E-mail: pjj0630@163.com , zuoyanwang@163.com Manuscript received February 25, 2017, revised manuscript October 16, 2017, accepted October 18, 2017 DOI: 10.5935/abc.20180034 Abstract Background: The intracoronary high-thrombus burden during the primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction (STEMI) can lead to poor outcomes. Monocytes have been described to play an important role in thrombotic disorders. Objectives: This study aimed to investigate the relationship between admission monocyte count and angiographic intracoronary thrombus burden in patients receiving primary percutaneous coronary intervention (PPCI). Methods: A total of 273 patients with acute STEMI who underwent PPCI were enrolled. The patients were divided into two groups according to the thrombolysis in myocardial infarction (TIMI) thrombus grade: low-thrombus burden group with a grade of 0–2 and high-thrombus burden group with a grade of 3-4. The monocyte count and other laboratory parameters were measured on admission before PPCI. P-value < 0.05 was considered significant. Results: There were 95 patients (34.8%) in the high-thrombus burden group, and 178 patients (65.2%) in the low‑thrombus burden group. Patients with high-thrombus burden had significantly higher admission monocyte count (0.61 ± 0.29×10 9 /L vs. 0.53 ± 0.24×10 9 /L, p = 0.021). In multivariate analysis, monocyte count was the independent predictor of angiographic high-thrombus burden (odds ratio 3.107, 95% confidence interval [CI] 1.199–7.052, p = 0.020). For the prediction of angiographic high-thrombus burden, admission monocyte count at a cut-off value of 0.48×10 9 /L yielded 0.59 ROC-AUC (71.9% sensitivity, 46.9% specificity). Conclusions: Monocyte count on admission was an independent clinical predictor of high-thrombus burden in patients with STEMI undergoing PPCI. Our findings suggest that admission monocyte count may be available for early risk stratification of high-thrombus burden in acute STEMI patients and might allow the optimization of antithrombotic therapy to improve the outcomes of PPCI. (Arq Bras Cardiol. 2018; 110(4):333-338) Keywords: Myocardial Infarction; Percutaneous Coronary Intervention/methods; Coronary Thrombosis/diagnostic imaging; Monocytes. Introduction Complete thrombotic occlusion of a major epicardial coronary artery is the common pathophysiological mechanism of acute ST-segment elevation myocardial infarction (STEMI). Primary percutaneous coronary intervention (PPCI) of the infarct-related artery in patients with STEMI is associated with prompt restoration of normal blood flow and improved clinical outcomes. However, clinical studies have shown that a high burden of peri-procedural intracoronary thrombus is an essential contributor of low thrombolysis in myocardial infarction (TIMI) flow grade and impaired myocardial perfusion. Identification of relationships between blood cell-related biomarkers and blood flow state during PPCI procedure is one of the current research focuses. Studies have revealed that monocytes may be involved in the pathogenesis of coronary artery disease 1 and elevated monocyte count is a risk factor for myocardial infarction. 2 Previous studies have shown that monocytes play an important role in thrombotic disorders, not only via the secretion of pro‑coagulant factors, such as tissue factor, but also by promoting inflammation processes. In our previous reports, monocyte counts on admission independently predict no‑reflow following primary PPCI. 3 In the current study, we aimed to investigate further the relationship between on admission monocyte count and angiographic intracoronary thrombus burden in patients receiving PPCI. Methods Study population We enrolled 273 consecutive patients with STEMI undergoing PPCI within 12h from symptom onset between 333