Evolution and Impact of a Regional Reperfusion System for ST-Elevation Myocardial Infarction

We describe the evolution of a regional system designed to provide primary percutaneous coronary intervention (pPCI) as the preferred method of revascularization for ST-elevation myocardial infarction (STEMI) and its impact on first medical contact (FMC)-to-device times and in-hospital outcomes.

Patients with STEMI presenting to the Vancouver Coastal Health Authority between June 2007 and January 2015 (N = 2503) were categorized according to 3 sequential phases: phase 1 = standardization of reperfusion algorithms; phase 2 = use of prehospital electrocardiograms; phase 3 = expedited interfacility transfer for pPCI. In-hospital outcomes by phase and hospital type were analyzed using multivariable logistic regression techniques.

Regional pPCI use increased across phases (55.0% vs 72.5% vs 86.7%; P < 0.001) and median FMC-to-device times shortened between phase 1 and later phases at both PCI-capable (117 minutes vs 92 minutes vs 97 minutes, respectively; P < 0.001) and non-PCI-capable hospitals (174 minutes vs 146 minutes vs 123 minutes, respectively; P < 0.001). Overall in-hospital mortality (9.4% vs 8.9% vs 10.3%, respectively; P = 0.54) and congestive heart failure (CHF) (15.8% vs 19.7% vs 22.0%, respectively; P = 0.056) were unchanged across phases. A trend toward increased mortality (9.0% vs 9.3% vs 12.9%, respectively; P = 0.079) and higher rates of CHF (15.7% vs 21.5% vs 25.9%, respectively; P = 0.014) were seen in PCI-capable hospitals.

Our regional STEMI model increased access to pPCI and reduced median reperfusion times. However, FMC-to-device times remained prolonged in many patients and overall clinical outcomes were not improved-in particular at PCI-capable hospitals. A strategy of pPCI as the preferred method of reperfusion may not benefit all patients in a regional model of STEMI care.