Cytokine profile and ST-elevation myocardial infarction.

Editorial " Give me fever and I can cure any disease. " – Hippocrates I n this issue of Circulation Research, Ammirati et al 1 have obtained data from 109 patients with ST-elevation myocar-dial infarction (STEMI) with the highest interleukin (IL)-6 levels compared with 96 patients with the lowest IL6 levels to identify differences in interacting cytokine levels that might predict clinical outcomes. They identified 2 different modules of patients from their circulating cytokine levels. One module included STEMI patients with increases in IL6(+) IL10(+), greater systolic dysfunction at discharge, and death at 6 months compared with IL6(−) IL10(+) STEMI patients. Combining IL10 with IL6 derived from the 2 identified cy-tokine modules provided a risk index combined-cytokine-index called the " AC-Index " that outperformed any single cytokine in the prediction of systolic dysfunction and death. The authors concluded that simultaneous elevation of IL6 and IL10 levels distinguishes STEMI patients with poorer clinical outcomes from other STEMI patients. They suggest that this information may have potential clinical implications for risk-oriented stratification and for immune-moderating therapies. IL6 is a cytokine associated with inflammation. Others have reported its value in predicting prognosis in patients during a 3-year follow-up of patients with acute STEMI. 2 The IL6 concentrations and 2 promoter polymorphisms of the IL6 gene in STEMI patients treated with thrombolysis 3 have also helped to identify higher-risk patients. Lindmark et al 4 have shown a relationship between IL6 levels and mortality in patients with unstable coronary artery disease. Biasucci et al 5 have shown that IL6 levels are elevated in patients with unstable angina. In the Prospective Epidemiological Study of Myocardial Infarction study, Empana et al 6 showed that C-reactive protein , IL6, and fibrinogen levels are related to the risk of sudden death in European middle-aged men. Ridker et al 7 have shown that IL6 levels predict the risk of future myocardial infarctions in apparently healthy men. IL6 serum levels are well established as a prognostic marker for patients with acute coronary syndromes. Maseri 8 has been an important contributor over many years to this area of work. We clearly need improved prognostic insights for patients with STEMI after their initial treatment. The new AC-index described by the authors in this article suggests that cytokine profiling may be useful beyond the prognostic insight provided by measurement of IL6 levels. However, there are some concerns with the AC-index as proposed. First, IL10 …