Relationship of admission mean platelet volume, platelet distribution width and white blood cells with ST resolution in patients with acute ST segment elevation myocardial infarction treated with streptokinase without history of previous cardiovascular surgery

Abstract

Background: Mean platelet volume (MPV) and platelet distribution width (PDW), markers of platelet reactivity, and white blood cell count (WBC-C), a marker of inflammation, have been shown to be predictive of unfavorable outcomes among survivors of ST elevation myocardial infarction (STEMI). we aimed to evaluate the value of admission of MPV, PDW and WBC-C for the prediction of ST segment resolution, in patient with acute STEMI treated with Streptokinase.

Materials and methods: This cross sectional study conducted on 280 patients with STEMI treated with streptokinase, from August 2009 until August 2011, in Afshar cardiovascular center, Yazd, Iran. Blood samples were obtained on admission in 280 patients with STEMI. According to sum of ST segment resolution and Schroder's method, patients divided two groups ((patients with ST resolution≥ 70% versus group with ST resolution < 70%)). The best cut off value of MPV, PDW and WBC-C for prediction of ST resolution (STR) were identified by using the receiver operating characteristic curve. The optimum cut off level was determined by selecting points of test value that provided the greatest sum of sensitivity and specificity.

Results: Of 280 patients enrolled this study, 39.3% of the patients with STR≥70% and in 60.7% with STR<70% were found. Patients in the STR < 70% group had higher admission MPV (10.6 ± 0.8 vs. .9.5 ± 0.8, P = 0.00) and higher PDW (13.8 ± 1.8 vs. 11.8 ± 1.7, P = 0.00)and higher WBC-C (12.1 ± 3.1 vs. 10.5 ± 2.5, P = 0.00) compare with patients with ST resolution ≥ 70%. The best cut off value of MPV for predicting STR < 70%was 10/05 fl (sensitivity 71/8 and specificity 80.9%) and for PDW was 12.85 fl (sensitivity 71.2% and specificity 83.6%) and for WBC-C was 12.65 × 1000 (sensitivity 42.9% and specificity 82.7%). The greatest area under the receiver operating characteristic (ROC) curve and greatest predicting value for ST resolution lower 70% was due to PDW (area = 0.812, P = 0/00).

Conclusion: MPV, PDW and WBC-C at admission might be valuable in the prediction of impaired STR and in planning the need for adjunctive therapy to improve outcomes with STEMI treated with Streptokinase. We can speculate that acute STEMI patients having MPV-PDW and WBC-C values above their's cut off patients should be considered for stronger antiplatelet and helps anti inflammation treatment to be able to attain a favorable ST resolution and better clinical outcome.

Keywords: Mean platelet volume; ST segment resolution; platelet distribution width; white blood cell count.

Figure 1

The receiver operating characteristic (ROC) curve for white blood cell, platelet distribution width and mean platelet volume to predict impaired reperfusion in patients treated with streptokinase.