Reduction in mortality as a result of direct transport from the field to a receiving center for primary percutaneous coronary intervention

Abstract

Objectives: This study sought to determine whether mortality complicating ST-segment elevation myocardial infarction (STEMI) was impacted by the design of transport systems.

Background: It is recommended that regions develop systems to facilitate rapid transfer of STEMI patients to centers equipped to perform primary percutaneous coronary intervention (PCI), yet the impact on mortality from the design of such systems remains unknown.

Methods: Within the framework of a citywide system where all STEMI patients are referred for primary PCI, we compared patients referred directly from the field to a PCI center to patients transported beforehand from the field to a non-PCI-capable hospital. The primary outcome was all-cause mortality at 180 days.

Results: A total of 1,389 consecutive patients with STEMI were assessed by the emergency medical services (EMS) and referred for primary PCI: 822 (59.2%) were referred directly from the field to a PCI center, and 567 (40.8%) were transported to a non-PCI-capable hospital first. Death at 180 days occurred in 5.0% of patients transferred directly from the field, and in 11.5% of patients transported from the field to a non-PCI-capable hospital (p < 0.0001. After adjusting for baseline characteristics in a multivariable logistic regression model, mortality remained lower among patients referred directly from the field to the PCI center (odds ratio: 0.52, 95% confidence interval: 0.31 to 0.88, p = 0.01). Similar results were obtained by using propensity score methods for adjustment.

Conclusions: A STEMI system allowing EMS to transport patients directly to a primary PCI center was associated with a significant reduction in mortality. Our results support the concept of STEMI systems that include pre-hospital referral by EMS.