The effect of on-admission mean platelet volume on TIMI frame count measured after fibrinolytic therapy in patients with acute ST-segment elevation myocardial infarction

Objectives: Mean platelet volume has been reported as a predicator of unfavorable prognosis in patients with STsegment elevation myocardial infarction (MI). We evaluated the relationship between the on-admission mean platelet volume and the response to fibrinolytic therapy using the TIMI frame count in patients with acute ST-segment elevation MI. Study Design: The study included 87 patients (58 males, 29 females; mean age 55 +/- 11 years) who received fibrinolytic therapy within the first 12 hours of symptom onset for acute STsegment elevation MI. Venous blood samples were obtained to determine the on-admission mean platelet volume and fibrinolytic therapy was administered. Coronary angiography was performed within the first 72 hours and the TIMI frame count was measured for infarct-related artery. TIMI frame count of <40 and ? 40 were defined as complete and incomplete reperfusion, respectively. Results: Reperfusion was complete in 35 patients (40.2%) and incomplete in 52 patients (59.8%). The mean TIMI frame counts were 31.8 +/- 5.9 and 61.2 +/- 15.3 in patients with complete and incomplete reperfusion, respectively (p<0.01). Patients with complete reperfusion had a significantly lower mean platelet volume (9.4 +/- 0.4 fl vs. 9.7 +/- 0.3 fl; p=0.016). There was a highly significant correlation between mean platelet volume and incomplete reperfusion (r=0.742, p<0.0001). Conclusion: High levels of on-admission mean platelet volume might be associated with insufficient reperfusion response to fibrinolytic therapy in patients with acute STsegment elevation MI.