ABC | Volume 112, Nº6, June 2019

Original Article Ding et al The clinical significance of platelet parameters such as MPV Arq Bras Cardiol. 2019; 112(6):715-719 Figure 1 – ROC curves of PLT, PDW, MPV, PCT, WBC and NEU for predicting AMI. PLT: platelet count; MPV: mean platelet volume; PCT: plateletcrit; PDW: platelet distribution width; WBC: white blood cell; NEU: neutrophils; AMI: acute myocardial infarction. 1.0 1.0 0.8 0.8 0.6 0.6 0.4 0.4 0.2 0.2 0.0 0.0 1 – Specificity Sensitivity ROC Curve PLT MPV PCT PDW WBC NEU Reference Line Figure 2 – ROC curves of PLT, PDW, MPV, PCT, WBC and NEU for predicting SCAD. ROC, receiver operating characteristics; PLT: platelet count; MPV: mean platelet volume; PCT: plateletcrit; PDW: platelet distribution width; WBC: white blood cell; NEU: neutrophils; SCAD: stable coronary artery disease. 1.0 1.0 0.8 0.8 0.6 0.6 0.4 0.4 0.2 0.2 0.0 0.0 1 – Specificity Sensitivity ROC Curve PLT MPV PCT PDW WBC NEU Reference Line Discussion The key mechanisms of ACS include coronary plaque rupture, platelet aggregation and thrombus formation. Mounting evidence has revealed that inflammation is an important precipitating event in the pathogenesis of ACS. 8 Inflammatory response plays an important role in the process of the occurrence, development and prognosis of coronary heart diseases. As markers of inflammatory response, WBC and NEU are closely correlated to cardiovascular system diseases. Studies have revealed that both can directly reflect the level of inflammation in coronary artery lesions, thereby further reflecting the severity of coronary artery lesions. 9,10 Studies have confirmed that the NEU/lymphocyte ratio could serve as a predictor of major adverse cardiovascular events. 11-13 This study revealed that there was a leukocyte-mediated inflammatory response in patients with AMI and that serum leukocyte levels were higher in SCAD and AMI patients than in normal healthy subjects. Furthermore, serum NEU levels were significantly abnormal in AMI patients, suggesting that inflammatory response is more intense in AMI patients. Hence, we consider that the reason may be that the range of inflammation is broader in myocardial infarction. MPV reflects the degree of activation of platelets to a certain extent and is considered an important marker of cardiovascular disease. 14 Furthermore, it can be used in risk prediction, diagnosis and prognosis assessment of cardiovascular diseases. 15-17 A recent study revealed that MPV significantly increased in patients with AMI, and the increase in MPV was correlated to the long-term prognosis of AMI patients to a certain extent. 18 Our study also revealed that MPV was significantly increased in patients in the AMI and SCAD groups. The increase in MPV is likely correlated to the intensity of inflammatory response in the body. 717