TO INVESTIGATE THE LEVELS OF PLASMA sP-SELECTIN AND THE LINK BETWEEN PLASMA SP- SELECTIN LEVELS AND THE CIRCULATING WBC COUNT IN PATIENTS WITH ACUTE MYOCARDIAL INFARCTION (AMI)

This study was aimed to investigate the levels of plasma sP-selectin and the link between plasma sPselect in levels and the circulating WBC count in patients with AMI. A total of 274 adults (18 years above) patients with clinically suspected acute coronary syndrome who attended in cardiac emergency and admitted in coronary care unit in the department of Cardiology, King George’s Medical University, India were enrolled in this study. Among them 248 patients had ECG changes (ST-elevation, STdepression, T-inversion, appearance of Q-wave) with or without elevated troponin I and treated with anti-platelet drugs. They were considered as cases (group I). The rest 26 Patients had normal ECG findings, normal cardiac troponin I and did not receive anti-platelet therapy. They were considered as controls (group II). Clinical history, medical reports, findings and information were documented in a pre-designed data sheet with informed and written consent. Blood samples for plasma levels of sP-selectin were obtained in the catheterization laboratory before coronary angiography. Descriptive statistical analyses were performed using SPSS software (version 20, 2008). The study samples were 274 patients, with a mean age of 59.29±11.94 years in cases group and 40.54±19.15 years in control group. Male patient proportion was higher than female in both groups. In cases group, correlation between sP selectin with WBC shows Pearson correlation coefficient (r), and their significance value, sP selectin were directly associated with WBC and demonstrate a significant positive relation (r=0.234, p=0.010). sP-selectin was markedly elevated in cases of AMI. sP-selectin may be involved in modulating the recruitment of circulating WBC during AMI. These findings raise the need for a prospective investigation of sPselectin as a potential reliable clinical tool for rapidly diagnosing AMI.


INTRODUCTION
Acute myocardial infarction (AMI) is the main cause of death in patients hospitalized with cardiovascular disease in industrialized societies [1].The underlying cellular and molecular mechanisms of disease initiation and progression are quite complex [2][3][4].An early event in vessel injury is the adhesion of platelets and leukocytes to the damaged arterial wall [5][6].Growing evidence has demonstrated that an acute inflammatory process which results in platelet aggregation and leukocyte adhesion to the endothelium in the coronary circulation plays a crucial role in thrombus formationand subsequently in the development of AMI [7].P-selectin, a cellular adhesion molecule of platelets and endothelial cells stored in both the α-granules of platelets and in the Weibel-Palade bodies of endothelial cells [8], is rapidly expressed on the surface of activated platelets and endothelial cells [9]. It is involved in mediating platelets and the rolling of leukocytes on activated endothelial cellsas well as in interactions of activated platelets with leukocytes [10]. Soluble P-selectin (sP-selectin), is a form of P-selectin which can be detected in plasma and represents a marker of platelet activation. Until recently, little data on plasma levels of sP-selectin were avail-able in patients with acute coronary syndromes [11].Only two recent studieshave investigated the plasma levels of sP-selectin following AMI. They demonstrated that the levels of sPselectin are significantly higher in patients in the clinical setting of AMI who are undergoing thrombolytic therapy than in healthy control subjects. Furthermore, while leukocyte accumulation plays an important role in promoting fibrin deposition [7], the relationship between increased plasma levels of sP-selectin and the recruitment of circulating WBC in patients with AMI remains undetermined. Whether sP-selectin 16573 | P a g e can be utilized as a marker for an early, rapid diagnosis of AMI is also uncertain. This study was proposed to investigate the levels of plasma sP-selectin and the link between plasma sPselectin levels and the circulating WBC count in patients with AMI.  II). Clinical history, medical reports, findings and information were documented in a pre-designed data sheet with informed and written consent. Blood samples for plasma levels of sPselectin were obtained in the catheterization laboratory before coronary angiography and determined by auto-mated analyzer.

Statistical analysis
Descriptive statistical analyses were performed using SPSS software (version 20, 2008). Data were summarized as Mean±SD. Groups (Present vs Absent (controls) were compared by unpaired or independent Student's t test. A twotailed p<0.05 was considered statistically significant.

RESULTS
The study samples were 274 patients, with a mean age of 59.29±11.94 years in cases group and 40.54±19.15 years in control group (Table 1).
The sex ratio in our study population showed that male patient proportion was higher than female in both groups (Table 2).
Regarding sP-selectin, it was significantly higher in the cases compared to the control (P = 0.001) ( Table 3). In cases group, correlation between sP selectin with WBC shows Pearson correlation coefficient (r), and their significance value, sP selectin were directly associated with WBC and demonstrate a significant positive relation (r=0.234, p=0.010) ( Table 4, Figure 1).

DISCUSSION
Platelet activation that results from coronary plaque rupture is vital in the pathogenesis of AMI. Soluble p-selectin (sPselectin) is crucial in modulating leukocyte adhesion to both platelets and endothelial cells during inflammatory response and thrombus formation. This study was proposed to investigate the levels of plasma sP-selectin and the link between plasma sP-selectin levels and the circulating WBC count in patients with AMI. The study samples were 274 patients, with a mean age of 59.29±11.94 years in cases group and 40.54±19.15 years in control group. Male patient proportion was higher than female in both groups. Correlation analysis demonstrated that the increase in the plasma level of sP-selectin was significantly related to the circulating WBC count similar to other prospective cohort study of 142 consecutive patients with ST-segment elevated AMI of onset < 12 h who were undergoing primary percutaneous coronary intervention [12]. In another studya significant positive correlation was found between plasma sP-selectin and serum ferritin as well as total leucocytic count reflecting the interplay between platelet activation, iron free radicals and inflammation [13].