Impact of the prehospital activation strategy in patients with ST-elevation myocardial infarction undergoing primary percutaneous revascularization: a single center community hospital experience.

The strategy of prehospital activation by the emergency medical system (EMS) in patients with ST-elevation myocardial infarction (STEMI) has been poorly adopted among the US hospitals that currently offer 24/7 primary percutaneous coronary intervention. In this study, we report a single center experience after the implementation of this strategy. From 2008 to 2011, we identified a total 188 STEMI patients (age 65 ± 15 years) presenting via EMS for primary percutaneous coronary intervention. Of these, 112 (59.6%) underwent prehospital activation (EMS group), whereas the remaining 76 (40.4%) underwent emergency department activation [emergency department (ED) group]. Baseline demographic characteristics were similar between both groups. The overall median door-to-balloon (DTB) time was 49 ± 14 minutes. Patients undergoing prehospital activation had on average significantly lower overall DTB times (EMS 44 ± 11 minutes vs. ED 57 ± 15 minutes; P < 0.001). Concordantly, DTB times <60 minutes were much more commonly achieved with this strategy (EMS 95.5% vs. ED 64.5%; P < 0.001). Fallouts beyond the recommended 90-minute DTB time were seen among ED patients only. No difference in in-hospital death (EMS 5.4% vs. ED 6.6%; P = 0.75) or cumulative 30-day mortality (EMS 6.3% vs. ED 7.9%; P = 0.68) was observed between both groups. However, on average, EMS patients had higher postinfarct left ventricular ejection fraction (EMS 48 ± 9.5% vs. ED 39 ± 14.6%; P = 0.004). Differences in DTB time and left ventricular ejection fraction remained significant after adjusting for differences in baseline characteristics. In conclusion, the prehospital activation strategy is largely effective and should be systematically adopted in the treatment scheme of STEMI patients to lower mechanical reperfusion times and reduce the potential for untoward clinical outcomes.

Use of the Impella 2.5 system alone, after and in combination with an intra-aortic balloon pump in patients with cardiogenic shock: case description and review of the literature.

Cardiogenic shock remains a serious complication of acute myocardial infarction as it is associated with very poor prognosis. Despite the historical clinical benefits of the intra-aortic balloon pump (IABP), in some patients additional mechanical cardiac support is necessary. The recent introduction of the percutaneous Impella® 2.5 mechanical circulatory support system (Abiomed Inc., Danvers, MA, USA) represents a major advancement and has been used in these circumstances. Nevertheless, the data supporting the use of this technology alone, after, or in combination with the IABP in patients with cardiogenic shock is limited and the clinical benefits remain unproven. We herein provide an updated comprehensive overview of the literature supporting the use of the Impella 2.5 system compared to the use of IABP in patients with cardiogenic shock. We also discuss the potential role for combination therapy for a patient with refractory shock. We describe a case in which an IABP was used as a bail-out strategy to provide additional haemodynamic support in a patient with refractory cardiogenic shock after the Impella 2.5 system was in place. In selected cases of refractory cardiogenic shock, the use of combined therapy with both the the Impella 2.5 and IABP can provide enhanced circulatory support and could be considered an option to maintain haemodynamic support in these patients.