New Data on the Prognostic Value of Inflammatory Markers in Patients with Acute Coronary Syndrome

The PACS study (Prognosis in Acute Coronary Syndromes) was conducted in 1500 patients with nonST-segment elevation acute coronary syndrome (NSTEACS) in 11 coronary care units of Argentina from January 2000 to May 2002. (1, 2) The purpose of this prospective, multicentric study was to establish the prognostic value of different biomarkers in these patients ́ risk stratification. (1, 2) The study of Hirschson Prado et al. (3) published in this issue of the Argentine Journal of Cardiology specifically addressed whether white blood cell (WBC) count on admission is related to the complexity of coronary lesions and prognosis of patients with NSTEACS. Out of the total number of patients with NSTEACS included in the angiographic PACS substudy, the authors selected for their analysis 580 patients undergoing early coronary angiography (median time of 48 hours) and WBC count within 24 hours of admission. The study population was divided into percentiles according to WBC count (< 7700, between 7700 and 11500 and > 11500/ mm3). Results showed that patients with higher WBC level frequently presented more complicated plaques and visible thrombus in the coronary angiography as well as more extensive coronary disease. In addition, at 6-month follow-up, the incidence of the composite adverse event of death or myocardial infarction was double in these patients. (3) Study results show that in patients with NSTEACS, elevation of WBC on admission is associated not only with more complex coronary lesions but also with worse mid-term prognosis. These findings are very relevant, firstly, for the simplicity of the proposal in studying WBC count on admission in patients with NSTEACS, and secondly, due to its relevant implications. (3) Moreover, the study generates many interesting considerations. (3) As in any observational study, it would be important to know whether the population selected for this analysis differs from the general population of the PACS study to justify the external validity of results. It is probable that only the most severely ill patients were selected for early coronary angiography and that they under-