Fibrinolytic therapy versus primary percutaneous coronary interventions for ST-segment elevation myocardial infarction in Kentucky: time to establish systems of care?

BACKGROUND: Fibrinolytic therapy is recommended for ST-segment myocardial infarctions (STEMI) when primary percutaneous coronary intervention (PPCI) is not available or cannot be performed in a timely manner. Despite this recommendation, patients often are transferred to PPCI centers with prolonged transfer times, leading to delayed reperfusion. Regional approaches have been developed with success and we sought to increase guideline compliance in Kentucky.
METHODS: A total of 191 consecutive STEMI patients presented to the University of Kentucky (UK) Chandler Medical Center between July 1, 2009 and June 30, 2011. The primary outcome was in-hospital mortality and the secondary outcomes were major adverse cardiovascular events, extent of myocardial injury, bleeding, and 4) length of stay. Patients were analyzed by presenting facility-the UK hospital versus an outside hospital (OSH)-and treatment strategy (PPCI vs fibrinolytic therapy). Further analyses assessed primary and secondary outcomes by treatment strategy within transfer distance and compliance with American Heart Association guidelines.
RESULTS: Patients presenting directly to the UK hospital had significantly shorter door-to-balloon times than those presenting to an OSH (83 vs 170 minutes; P < 0.001). This did not affect short-term mortality or secondary outcomes. By comparison, OSH patients treated with fibrinolytic therapy had a numeric reduction in mortality (4.0% vs 12.3%; P = 0.45). Overall, only 20% of OSH patients received timely reperfusion, 13% PPCI, and 42% fibrinolytics. In a multivariable model, delayed reperfusion significantly predicted major adverse cardiovascular events (odds ratio 3.87, 95% confidence interval 1.15-13.0; P = 0.02), whereas the presenting institution did not.
CONCLUSIONS: In contemporary treatment of STEMI in Kentucky, ongoing delays to reperfusion therapy remain regardless of treatment strategy. For further improvement in care, acceptance of transfer delays is necessary and institutions should adopt standardized protocols in association with a regional system of care.