['We aimed to investigate the association between platelet-leukocyte aggregates (PLA) levels on admission and the risk of myocardial no-reflow in patients with ST elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI).', 'A total of 83 patients with STEMI undergoing primary PCI were included in the current study. Platelet-leukocyte conjugates (PLA), including platelet-monocyte aggregates (PMA), platelet-neutrophil aggregates (PNA) and platelet-lymphocyte aggregates were studied by flow cytometry in peripheral venous blood. No-reflow was defined as coronary blood flow grade thrombolysis in myocardial infarction ≤2 or thrombolysis in myocardial infarction 3 and myocardial blush grade ≤2.', 'No-reflow was observed in 19 patients (22.9%). Compared with the reflow group, the level of PNA (76.5 ± 13.3) and PMA (90.3 ± 5.2) before PCI no-reflow group was significantly higher than that in normal reflow (P < 0.001). Using multiple logistic regression analysis, PNA (odds ratio [OR] = 1.179; 95% CI: 1.035-1.342; P = 0.013) and PMA (OR = 1.248; 95% CI: 1.040-1.498; P = 0.017) were found to be a significant predictor of no-reflow together with pain to balloon time (OR = 1.022; 95% CI: 1.002-1.041; P = 0.028), estimated glomerular filtration rate (OR = 1.311; 95% CI: 1.009-1.856; P = 0.047) and higher thrombus burden (OR = 0.061; 95% CI: 0.006-0.658; P = 0.021). Receiver operating characteristic curve analysis revealed that PNA (area under the curve = 0.881; 95% CI: 0.809-0.952; P < 0.001), PMA (area under the curve = 0.794; 95% CI: 0.699-0.889; P < 0.001) have important predictive value for the myocardial no-reflow.'] Do increased Platelet-leukocyte Aggregates Are Associated With Myocardial No-reflow in Patients With ST Elevation Myocardial Infarction?