Appropriate utilization of acute reperfusion therapy is not a national performance measure for ST-elevation myocardial infarction at this time, and the extent of its contemporary use among ideal patients is unknown.

From the National Registry of Myocardial Infarction, we identified 238,291 patients enrolled from June 1994 to May 2003 who were ideally suited for acute reperfusion therapy with fibrinolytic therapy or primary percutaneous coronary intervention. We determined rates of not receiving therapy across 3 time periods (June 1994-May 1997, June 1997-May 2000, June 2000-May 2003) and evaluated factors associated with underutilization.

The proportion of ideal patients not receiving acute reperfusion therapy decreased by one half throughout the past decade (time period 1: 20.6%; time period 2: 11.4%; time period 3: 11.6%; P <.001). Utilization remained significantly lower in key subgroups in the most recent time period: those without chest pain (odds ratio [OR] 0.29; 95% confidence interval [CI], 0.27-0.32); those presenting 6 to 12 hours after symptom onset (OR 0.57; 95% CI, 0.52-0.61); those 75 years or older (OR 0.63 compared with patients <55 years old; 95% CI, 0.58-0.68); women (OR 0.88; 95% CI, 0.84-0.93); and non-whites (OR 0.90; 95% CI, 0.83-0.97).

Utilization of acute reperfusion therapy in ideal patients has improved over the last decade, but more than 10% remain untreated. Measuring and improving its use in this cohort represents an important opportunity to improve care.