Delays in fibrinolysis as primary reperfusion therapy for acute ST-segment elevation myocardial infarction

In contemporary practice, the degree to which fibrinolytic therapy is administered in a timely fashion for ST-segment elevation myocardial infarction (STEMI) and its association with outcomes is not well-known. Our objective was to assess the performance of fibrinolytic therapy within the recommended 30-minute time frame for patients with STEMI.

Patient characteristics associated with the timeliness of fibrinolytic therapy were evaluated. We also examined the association of timely fibrinolysis with key patient outcomes, including inpatient mortality, stroke, and cardiogenic shock. Logistic generalized estimating equations were used to account for baseline clinical factors and within-hospital clustering.

Between January 2007 and June 2008, 3,219 STEMI patients in 178 hospitals received primary fibrinolytic therapy. Median door-to-needle (DTN) time was 34.0 minutes (interquartile range 22.0-54.0 minutes). However, only 44.5% met the American College of Cardiology/American College of Cardiology guideline DTN time of < or =30 minutes. Patient characteristics associated with longer fibrinolysis times included female gender (+17.8% longer vs men, 95% CI 11.9-24.1) and age > or =75 (+12.0% longer vs age <55, 95% CI 1.8-23.2). Timely (vs delayed) fibrinolysis was associated with a decreased risk of a composite outcome of death, shock, or stroke (6.2% vs 8.8%, adjusted odds ratio 0.74, 95% CI 0.56-0.98).

Timely fibrinolytic therapy was associated with lower risk of a composite outcome of shock, death, or stroke, yet DTN times of < or =30 minutes were achieved in less than half of the patients studied. Thus, efforts to optimize regional systems of STEMI care should focus on shortening reperfusion times for patients who receive fibrinolysis, as well as those who receive primary percutaneous coronary intervention.