[Analysis of reperfusion delay in patients with acute myocardial infarction treated with primary angioplasty based on first medical contact and time of presentation]

Introduction and objectives: In primary angioplasty, the interval between first medical contact (FMC) and reperfusion should be less than 120 minutes. The time to reperfusion varies depending on where FMC is established. Recent studies suggest longer times in patients presenting in off-hours. The objective is to evaluate the time intervals between the onset of symptoms and reperfusion according to where the FMC occurs and time of day of patient presentation.

Methods: Prospective observational study of acute myocardial infarction patients treated with primary angioplasty (February 2007 to May 2009). Depending on the FMC, patients were classified as belonging to the hospital group (hospital with primary angioplasty), the transfer group (hospital without primary angioplasty), or the emergency medical system (EMS) group (out-of-hospital care). For each group, the prehospital delay, diagnostic delay, delay in activation and/or transfer, and procedure delay were recorded.

Results: Primary angioplasty was performed in 457 patients: 155 in the hospital group, 228 in the transfer group and 72 in the EMS group. The median [interquartile range] door-to-reperfusion times were 80 [63-107], 148 [118-189] and 81 [66-98] minutes, respectively (P<.0001). The transfer group showed a greater delay in diagnosis (P<.0001) and delayed activation and/or transfer (P<.0001). The EMS group had the shortest total time due to a reduced prehospital delay (P=.001). No difference was found with regard to the time of presentation (P=.42).

Conclusions: Transfer group patients were treated later and EMS group patients much earlier. There were no differences in association with the time of presentation. The identification of inappropriate delays should enable the introduction of measures to improve the efficiency of treatment.