Objective: To evaluate the prognostic of interleukin 6 levels, in patients with acute myocardial infarction with No Reflow phenomenon. Methods: Consecutive patients with acute ST elevation myocardial infarction diagnosis, with ≤12 hours of evolution, and treated with primary angioplasty were included. The intracoronary interleukin 6 was measured before and after the procedure. The patients were classified into two groups: group I (Success or Reflow) and II (Failure or No Reflow) respectively. The early outcome variables were evaluated during the hospitalization. Results: A total of 45 patients were studied, the average age was 62 ± 11 years, 26 patients in the group I, and 19 in the group II, without differences in the traditional risk factor, or in the evolution time. Compared to group 1, the complications were more frequent in the group II, compared to group I: hypotension (7.7% vs. 63%, p