Abstract
Background Previous studies have demonstrated that an elevated neutrophil count on admission is associated with a higher risk of adverse events after acute myocardial infarction (AMI). However, the significance of the neutrophil count after reperfusion therapy has not been elucidated. Methods and Results The association of the neutrophil count on admission and days 2 and 3 with peak creatine kinase (CK) concentration, ST-segment resolution (a marker of myocardial tissue-level reperfusion), and left ventricular (LV) function at predischarge were examined in 122 patients (102 men, 20 women, mean age 61±11 years) with a first anterior wall AMI. Neutrophil counts were increased on day 2 and decreased on day 3 compared with admission (8,768±3,005 mm3, 6,617±2,424 mm3, and 7,725±3,388 mm3, respectively). Patients with ST-segment resolution (n=52) had lower neutrophil counts on days 2 and 3 than those without it (n=70), but neutrophil counts on admission did not differ significantly between patients with and without ST-segment resolution. Neutrophil counts on admission and days 2 and 3 were weakly but significantly correlated with peak CK concentration (r=0.31, p=0.0004; r=0.43, p<0.0001; r=0.32, p=0.003, respectively) and with LV ejection fraction at predischarge (r=-0.18, p=0.04; r=-0.26, p=0.003; r=-0.27, p=0.003; respectively). Conclusion The neutrophil count after reperfusion is weakly but significantly correlated with infarct size, myocardial tissue-level reperfusion, and LV function at predischarge in a first anterior wall AMI. These correlations were slightly stronger than the correlations with the neutrophil count on admission. (Circ J 2005; 69: 526 - 529)
