Role of platelet parameters and haematological indices in myocardial infarction and unstable angina

Abstract

Objective: To explore the significance of platelet parameters, including mean platelet volume, platelet count and other haematological indices, in patients of acute coronary syndrome. Methods: In this one-year retrospective cross-sectional study in 2010, a total of 631 patients were enrolled at the Cardiovascular Research Institute, Tabriz University of Medical Sciences, Iran, and classified into three groups: myocardial infarction, unstable angina, and Control. Cardiovascular risk factors such as smoking, diabetes mellitus, hyperlipidaemia and hypertension status were compared. Blood samples were collected for the measurement of platelet count, mean platelet volume and other haematological indices, including prothrombin time, partial thromoplastin time, blood group and Rh, haematocrit, haemoglobin, and erythrocyte sedimentation rate. SPSS 18 was used for statistical analysis. Results: Of the total, there were 210(33.3%; 163 men, 47 women) with myocardial infarction whose mean age was 62.7 +/- 14.2 years; 211(33.3%; 110 men, 101 women) had unstable angina with a mean age of 63.5 +/- 13.1 years and 210 (33.3%; 117 men, 90 women) health controls with a mean age of 60.6 +/- 12.8 years. The mean platelet volume values of patients in the first two groups were significantly higher than the control group (10.14 +/- 1.05 fL, 9.82 +/- 0.93 fL and 9.34 +/- 1.14 fL, respectively; p<0.001). The platelet count was detected to be significantly lower in the patients than the controls (207.92 +/- 58.40x109/L, 220.18 +/- 65.81x109/L, 238 +/- 56.10x109/L, respectively, p<0.001). While blood cell count was significantly higher in those with myocardial infarction compared to the unstable angina patients and control group (P<0.001). Differences in mean values of mean platelet volume between the two patient groups was not significant, but mean values of platelet count was statistically significant between these two groups (p<0.04). Conclusion: Mean platelet volume and platelet count may be considered prognostic markers for acute coronary syndrome.