Relation between white blood cell counts and myocardial reperfusion in patients with recanalized anterior acute myocardial infarction

Abstract

Background: The clinical significance of the white blood cell (WBC) count on admission in relation to the duration of ischemia in acute myocardial infarction (AMI) remains unclear. Methods and Results: The relationship of the WBC count on admission to myocardial reperfusion was examined in 135 patients with recanalization of an anterior AMI within 6h of symptom onset. Patients were classified according to the WBC count on admission: Group L (n=75), WBC count <12,000 cells/mm3 and group H (n=60), WBC count ≥12,000 cells/mm3. Peak creatine kinase (CK) was higher and impaired myocardial reperfusion, defined as a myocardial blush grade of 0/1, was more frequent in group H than in group L. Among the patients in group H, those with early (≤3 h) recanalization had a lower QRS score before recanalization than those with late (>3 h) recanalization; however, peak CK and the incidence of impaired myocardial reperfusion were similar in these subgroups of patients. Multivariate analysis showed that WBC count ≥ 12,000 cells/mm3 on admission was an independent predictor of impaired myocardial reperfusion in patients with early recanalization (odds ratio 7.9, p=0.04), but not in those with late recanalization. Conclusions: A higher WBC count may be associated with progression of myocardial damage after recanalization in patients with early recanalization of an anterior AMI.