Prehospital Care and Outcomes in Acute Myocardial Infarction

In one study, patients with AMI fared better when triaged in the ambulance and taken directly to a hospital that performs percutaneous coronary intervention, and, in another study, patients with symptoms for <2 hours fared better when treated with fibrinolysis than with primary PCI.


In a retrospective study at a single Dutch regional percutaneous coronary intervention (PCI) center from 1998 to 2008, researchers compared outcomes between 2840 patients with ST-segment-elevation myocardial infarction (STEMI) who were transported directly to the PCI center and 2288 who were transported to an affiliated non-PCI center and then transferred to the PCI center. Patients who were transported directly to the PCI center were triaged in the ambulance by a crew trained to perform and interpret electrocardiograms and to administer heparin, aspirin, and clopidogrel. Transferred patients received similar diagnostic and therapeutic interventions at the non-PCI center.

The prehospital triage group had significantly shorter median time from symptom onset to balloon inflation (184 vs. 260 minutes), smaller infarct size, and lower 1-year mortality (odds ratio, 0.67). All differences between the prehospital triage group and the transferred group were more marked among the subgroup of patients who resided >38 km from the PCI center.

In another study, researchers aggregated data from two trials (1 French, 1 Canadian) that enrolled patients with STEMI within 6 hours of onset of ischemic symptoms. In one trial, patients were randomized to prehospital fibrinolysis or primary PCI and, in the other trial, patients were randomized to one of three arms at the site of first contact (prehospital or hospital): fibrinolysis, fibrinolysis with PCI, or primary PCI.

Overall, among 1160 patients with complete data, 1-year mortality did not differ significantly between the combined early fibrinolysis groups and the primary PCI group. However, early fibrinolysis conferred significant 1-year mortality benefit in the subgroup of patients who presented within 2 hours of symptom onset (hazard ratio, 0.43).


Citation(s):

Postma S et al. Prehospital triage in the ambulance reduces infarct size and improves clinical outcome. Am Heart J 2011 Feb; 161:276.

Westerhout CM et al. The influence of time from symptom onset and reperfusion strategy on 1-year survival in ST-elevation myocardial infarction: A pooled analysis of an early fibrinolytic strategy versus primary percutaneous coronary intervention from CAPTIM and WEST. Am Heart J 2011 Feb; 161:283.