The white blood cell count is an independent predictor of no‐reflow and mortality following acute myocardial infarction in the coronary interventional era

BACKGROUND: In the era before the use of coronary reperfusion therapy, an elevated white blood cell (WBC) count was associated with a higher risk of adverse events following acute myocardial infarction (AMI). However, the relationship between WBC count and prognosis after AMI has not been investigated since coronary intervention was introduced. AIM: To evaluate whether a high WBC count within 48 hours of the onset of AMI predicts future adverse events in patients undergoing percutaneous coronary intervention (PCI). METHOD: We evaluated 1,016 patients who underwent PCI in the acute phase of MI using the Japanese Acute Coronary Syndrome Study (JACSS) database. RESULTS. WBC count was significantly associated with smoking, sudden onset AMI, and the no-reflow phenomenon during PCI, as were age, peak creatine kinase level, and Killip class. An elevated WBC count was significantly associated with higher risk of in-hospital mortality. Patients in the highest quartile of WBC count were about three times more likely to have a poor prognosis after AMI compared to those in the lowest quartile. CONCLUSIONS: The WBC count is of great significance for stratifying patient risk and can be used as a universal marker for predicting future adverse events following any treatment for AMI.